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Sample records for large sedimentary basins

  1. Relationship between small and large sedimentary basins: the scale spectrum

    SciTech Connect

    Dewey, J.F.; Karner, G.D.; Pitman, W.C.

    1986-07-01

    Realizing that detachments influence lithospheric extension helps us define the fundamental elements responsible for basin formation. In addition to strain rate, crustal thickness, and lithospheric thickness, these factors are (1) stretching distribution within the upper plate of the detachment, (2) stretching distribution within the lower plate, and (3) depth distribution of the detachment(s), where lateral strain must be balanced within the lithosphere during extension. Intracrustal duplex systems may reflect previous compressional events, or they may be produced by upper-crustal flaking in strike-slip regimes. Basin initiation represents a mechanical process (e.g., hanging-wall collapse), whereas subsequent basin development is primarily an isostatic process controlled by the thermal and mechanical properties of the lithosphere. However, subcrustal lithospheric involvement and, hence, heating are minimal until flexure becomes unimportant, which depends on basin wavelength, lithospheric temperature structure, and hence, rigidity. This wavelength or scale dependency may help explain the difference between the abrupt but short-lived subsidence of small basins, such as the Ridge basin of southern California, and the general negative exponential subsidence characteristic of passive continental margins. The rheological implications of depth-dependent stretching, with thermal modification of the lithosphere during extension, ultimately controls lithospheric strength and, hence, the actual rift/breakup configuration. Together, factors 1 and 2 generate rift and thermal subsidences, the final form of which depends on the flexural properties of the lithosphere. The exact relationship between factors 1 and 2 determines the spatial configuration between rift and sag basins and temporary uplifts. They illustrate these concepts and their implications with examples from California, Nevada, Brazil, Turkey, and Australia.

  2. South American sedimentary basins

    SciTech Connect

    Urien, C.M.

    1984-04-01

    More than 64 sedimentary basins have been identified on the South American continent. According to their regional structural character and tectonic setting, they are classified in 4 super groups. About 20 interior or intracratonic basins occur on South American cratons (Guayanas, Brazilian, and Patagonian). In most cases, their sedimentary fill is Paleozoic or early Mesozoic. Rift or transverse grabens resulting from incipient sea floor spreading extend towards the continental margin. Seventeen basins are located along the Atlantic stable margin, and consist primarily of half grabens with downfaulted seaward blocks. These rifts (or pull-apart basins) were separated as results of the migration of the African and American continental blocks. Therefore the sedimentation is chiefly Cretaceous and Tertiary. On the western edge of South American cratons, almost 20 basins of downwarped blocks extend from Orinoco down to the Malvinas plateau in a relatively uninterrupted chain of retroarc basins, bordered by the Andean orogen. They lie on a flexured Precambrian and Paleozoic basement, and are highly deformed in the west (Subandean belt) due to the action of compressional forces caused by the tectonic influence of the Mesozoic Andean batholith. Westward, the Pacific margin is bordered by 27 foreland and forearc basins, which alternate from north to south on an unstable or quasistable margin, fringed by a trench and slope complex where the ocean crust is subducted beneath the continental plate.

  3. Morphology, sedimentary features and evolution of a large palaeo submarine canyon in Qiongdongnan basin, Northern South China Sea

    NASA Astrophysics Data System (ADS)

    Li, Xiangquan; Fairweather, Luke; Wu, Shiguo; Ren, Jianye; Zhang, Hongjie; Quan, Xiayun; Jiang, Tao; Zhang, Cheng; Su, Ming; He, Yunlong; Wang, Dawei

    2013-01-01

    The large Miocene-aged palaeo canyon that extents through the Qiongdongnan basin (QDNB) and Yinggehai basin (YGHB) of Northern South China Sea has been of considerable interest both economically and scientifically over the past decade. Stemmed from this, significant research has been employed into understanding the mechanism for its existence, incision, and sedimentary fill, yet debate remains. In the first case the canyon itself is actually quite anomalous. Alone from the size (over 570 km in length and more than 8 km in width (Yuan et al., 2009)), which is considerably more than most ancient deep-water channels (REFS), the canyon's sedimentary fill is also distinctly different. Some explanations have been given to explain the canyon's origin and existence, these include increased sediment supply from the Red River which is genetically linked to uplift of the Tibetan Plateau, lowstand turbidite and mass-transport activity, reactivation and dextral displacement of the Red River Fault zone inducing erosive gravity-flows, regional tilt of the QDNB and YGHB, paleo-seafloor morphology and seal-level fluctuations. With the application of new data obtained from interpretations of a large number of 2D seismic profiles, core and well log data, and tectonic and sedimentary analysis this contribution aims to: (1) Present models to explain the Canyon's sedimentary fill and basin plain deposits, which provided significant understanding of processes pre-, syn- and post-incision and; (2) review the plausibility and likelihood of each of the controlling mechanisms, hoping to shed light on this controversial aspect. We conclude that the final erosive event that shaped the canyon is dated at 5.5 Ma. The Canyon's unusual fill is a product of variation in the interaction between turbidity currents and MTD that blocked the canyon's axis, and the reduction in gravity flow energy through time; and therefore the complete succession represents one major erosive and cut event at 5.5 Ma and

  4. Large-Scale Multiphase Flow Modeling of Hydrocarbon Migration and Fluid Sequestration in Faulted Cenozoic Sedimentary Basins, Southern California

    NASA Astrophysics Data System (ADS)

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

    2011-12-01

    Major fault systems play a first-order role in controlling fluid migration in the Earth's crust, and also in the genesis/preservation of hydrocarbon reservoirs in young sedimentary basins undergoing deformation, and therefore understanding the geohydrology of faults is essential for the successful exploration of energy resources. For actively deforming systems like the Santa Barbara Basin and Los Angeles Basin, we have found it useful to develop computational geohydrologic models to study the various coupled and nonlinear processes affecting multiphase fluid migration, including relative permeability, anisotropy, heterogeneity, capillarity, pore pressure, and phase saturation that affect hydrocarbon mobility within fault systems and to search the possible hydrogeologic conditions that enable the natural sequestration of prolific hydrocarbon reservoirs in these young basins. Subsurface geology, reservoir data (fluid pressure-temperature-chemistry), structural reconstructions, and seismic profiles provide important constraints for model geometry and parameter testing, and provide critical insight on how large-scale faults and aquifer networks influence the distribution and the hydrodynamics of liquid and gas-phase hydrocarbon migration. For example, pore pressure changes at a methane seepage site on the seafloor have been carefully analyzed to estimate large-scale fault permeability, which helps to constrain basin-scale natural gas migration models for the Santa Barbara Basin. We have developed our own 2-D multiphase finite element/finite IMPES numerical model, and successfully modeled hydrocarbon gas/liquid movement for intensely faulted and heterogeneous basin profiles of the Los Angeles Basin. Our simulations suggest that hydrocarbon reservoirs that are today aligned with the Newport-Inglewood Fault Zone were formed by massive hydrocarbon flows from deeply buried source beds in the central synclinal region during post-Miocene time. Fault permeability, capillarity

  5. 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.

  6. Inversion of Extensional Sedimentary Basins

    NASA Astrophysics Data System (ADS)

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

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

  7. Geothermal resources of California sedimentary basins

    USGS Publications Warehouse

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

    2004-01-01

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

  8. African sedimentary basins - Tectonic controls on prospectivity

    SciTech Connect

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

    1991-03-01

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

  9. Thermal evolution of sedimentary basins in Alaska

    USGS Publications Warehouse

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

    1996-01-01

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

  10. NATURAL GAS RESOURCES IN DEEP SEDIMENTARY BASINS

    SciTech Connect

    Thaddeus S. Dyman; Troy Cook; Robert A. Crovelli; Allison A. Henry; Timothy C. Hester; Ronald C. Johnson; Michael D. Lewan; Vito F. Nuccio; James W. Schmoker; Dennis B. Riggin; Christopher J. Schenk

    2002-02-05

    From a geological perspective, deep natural gas resources are generally defined as resources occurring in reservoirs at or below 15,000 feet, whereas ultra-deep gas occurs below 25,000 feet. From an operational point of view, ''deep'' is often thought of in a relative sense based on the geologic and engineering knowledge of gas (and oil) resources in a particular area. Deep gas can be found in either conventionally-trapped or unconventional basin-center accumulations that are essentially large single fields having spatial dimensions often exceeding those of conventional fields. Exploration for deep conventional and unconventional basin-center natural gas resources deserves special attention because these resources are widespread and occur in diverse geologic environments. In 1995, the U.S. Geological Survey estimated that 939 TCF of technically recoverable natural gas remained to be discovered or was part of reserve appreciation from known fields in the onshore areas and State waters of the United. Of this USGS resource, nearly 114 trillion cubic feet (Tcf) of technically-recoverable gas remains to be discovered from deep sedimentary basins. Worldwide estimates of deep gas are also high. The U.S. Geological Survey World Petroleum Assessment 2000 Project recently estimated a world mean undiscovered conventional gas resource outside the U.S. of 844 Tcf below 4.5 km (about 15,000 feet). Less is known about the origins of deep gas than about the origins of gas at shallower depths because fewer wells have been drilled into the deeper portions of many basins. Some of the many factors contributing to the origin of deep gas include the thermal stability of methane, the role of water and non-hydrocarbon gases in natural gas generation, porosity loss with increasing thermal maturity, the kinetics of deep gas generation, thermal cracking of oil to gas, and source rock potential based on thermal maturity and kerogen type. Recent experimental simulations using laboratory

  11. Physical Modelling of Sedimentary Basin

    SciTech Connect

    Yuen, David A.

    2003-04-24

    The main goals of the first three years have been achieved, i.e., the development of particle-based and continuum-based algorithms for cross-scaleup-scale analysis of complex fluid flows. The U. Minnesota team has focused on particle-based methods, wavelets (Rustad et al., 2001) and visualization and has had great success with the dissipative and fluid particle dynamics algorithms, as applied to colloidal, polymeric and biological systems, wavelet filtering and visualization endeavors. We have organized two sessions in nonlinear geophysics at the A.G.U. Fall Meeting (2000,2002), which have indeed synergetically stimulated the community and promoted cross-disciplinary efforts in the geosciences. The LANL team has succeeded with continuum-based algorithms, in particular, fractal interpolating functions (fif). These have been applied to 1-D flow and transport equations (Travis, 2000; 2002) as a proof of principle, providing solutions that capture dynamics at all scales. In addition, the fif representations can be integrated to provide sub-grid-scale homogenization, which can be used in more traditional finite difference or finite element solutions of porous flow and transport. Another useful tool for fluid flow problems is the ability to solve inverse problems, that is, given present-time observations of a fluid flow, what was the initial state of that fluid system? We have demonstrated this capability for a large-scale problem of 3-D flow in the Earth's crust (Bunge, Hagelberg & Travis, 2002). Use of the adjoint method for sensitivity analysis (Marchuk, 1995) to compute derivatives of models makes the large-scale inversion feasible in 4-D, , space and time. Further, a framework for simulating complex fluid flow in the Earth's crust has been implemented (Dutrow et al, 2001). The remaining task of the first three-year campaign is to extend the implementation of the fif formalism to our 2-D and 3-D computer codes, which is straightforward, but involved.

  12. Precambrian shield and basement tectonics in sedimentary basin analysis

    SciTech Connect

    Touborg, J.F.

    1984-04-01

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

  13. Geofluid Dynamics of Faulted Sedimentary Basins

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

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

  14. Hydrogeologic framework of sedimentary deposits in six structural basins, Yakima River basin, Washington

    USGS Publications Warehouse

    Jones, M.A.; Vaccaro, J.J.; Watkins, A.M.

    2006-01-01

    The hydrogeologic framework was delineated for the ground-water flow system of the sedimentary deposits in six structural basins in the Yakima River Basin, Washington. The six basins delineated, from north to south are: Roslyn, Kittitas, Selah, Yakima, Toppenish, and Benton. Extent and thicknesses of the hydrogeologic units and total basin sediment thickness were mapped for each basin. Interpretations were based on information from about 4,700 well records using geochemical, geophysical, geologist's or driller's logs, and from the surficial geology and previously constructed maps and well interpretations. The sedimentary deposits were thickest in the Kittitas Basin reaching a depth of greater than 2,000 ft, followed by successively thinner sedimentary deposits in the Selah basin with about 1,900 ft, Yakima Basin with about 1,800 ft, Toppenish Basin with about 1,200 ft, Benton basin with about 870 ft and Roslyn Basin with about 700 ft.

  15. 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.

  16. Sedimentary complexes of the cover of the Dzabkhan continental block: Different sedimentary basins and source areas

    NASA Astrophysics Data System (ADS)

    Letnikova, E. F.; Vishnevskaya, I. A.; Letnikov, F. A.; Vetrova, N. I.; Shkolnik, S. I.; Kostitsyn, Yu. A.; Karakovskii, E. A.; Reznitskii, L. Z.; Kanygina, N. A.

    2016-10-01

    The geochemical and Sm-Nd isotope characteristics of Late Precambrian and Early Cambrian sandstones previously related to the sedimentary cover of the Dzabkhan continental block are reported. It is established that the Riphean and Vendian sedimentary rocks of the Ul'zitgol'skaya and Tsaganolomskaya Formations were accumulated within the Dzabkhan continental block as a result of recycling of the terrigenous deposits formed at the expense of destruction of basement rocks and younger granite. The formation of terrigenous rocks of the Bayangol'skaya Formation after a gap in sedimentation occurred in the sedimentary basin, where only the Late Riphean formations of the juvenile crust, probably of the Dzabkhan-Mandal block were the sources, without the contribution of the ancient crustal material. The Tsaganolomskaya and Bayangol'skaya Formations were formed in different sedimentary basins and cannot be related to the same complex.

  17. Preliminary catalog of the sedimentary basins of the United States

    USGS Publications Warehouse

    Coleman, James L.; Cahan, Steven M.

    2012-01-01

    One hundred forty-four sedimentary basins (or groups of basins) in the United States (both onshore and offshore) are identified, located, and briefly described as part of a Geographic Information System (GIS) data base in support of the Geologic Carbon Dioxide Sequestration National Assessment Project (Brennan and others, 2010). This catalog of basins is designed to provide a check list and basic geologic framework for compiling more detailed geologic and reservoir engineering data for this project and other future investigations.

  18. Frontier sedimentary basins of New Zealand region

    SciTech Connect

    Beggs, J.M. )

    1991-03-01

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

  19. Sedimentary sequence evolution in a Foredeep basin: Eastern Venezuela

    SciTech Connect

    Bejarano, C.; Funes, D.; Sarzalho, S.; Audemard, F.; Flores, G.

    1996-08-01

    Well log-seismic sequence stratigraphy analysis in the Eastern Venezuela Foreland Basin leads to study of the evolution of sedimentary sequences onto the Cretaceous-Paleocene passive margin. This basin comprises two different foredeep sub-basins: The Guarico subbasin to the west, older, and the Maturin sub-basin to the east, younger. A foredeep switching between these two sub-basins is observed at 12.5 m.y. Seismic interpretation and well log sections across the study area show sedimentary sequences with transgressive sands and coastal onlaps to the east-southeast for the Guarico sub-basin, as well as truncations below the switching sequence (12.5 m.y.), and the Maturin sub-basin shows apparent coastal onlaps to the west-northwest, as well as a marine onlap (deeper water) in the west, where it starts to establish. Sequence stratigraphy analysis of these sequences with well logs allowed the study of the evolution of stratigraphic section from Paleocene to middle Miocene (68.0-12.0 m.y.). On the basis of well log patterns, the sequences were divided in regressive-transgressive-regressive sedimentary cycles caused by changes in relative sea level. Facies distributions were analyzed and the sequences were divided into simple sequences or sub- sequences of a greater frequencies than third order depositional sequences.

  20. PUMa - modelling the groundwater flow in Baltic Sedimentary Basin

    NASA Astrophysics Data System (ADS)

    Kalvane, G.; Marnica, A.; Bethers, U.

    2012-04-01

    In 2009-2012 at University of Latvia and Latvia University of Agriculture project "Establishment of interdisciplinary scientist group and modelling system for groundwater research" is implemented financed by the European Social Fund. The aim of the project is to develop groundwater research in Latvia by establishing interdisciplinary research group and modelling system covering groundwater flow in the Baltic Sedimentary Basin. Researchers from fields like geology, chemistry, mathematical modelling, physics and environmental engineering are involved in the project. The modelling system is used as a platform for addressing scientific problems such as: (1) large-scale groundwater flow in Baltic Sedimentary Basin and impact of human activities on it; (2) the evolution of groundwater flow since the last glaciation and subglacial groundwater recharge; (3) the effects of climate changes on shallow groundwater and interaction of hydrographical network and groundwater; (4) new programming approaches for groundwater modelling. Within the frame of the project most accessible geological information such as description of geological wells, geological maps and results of seismic profiling in Latvia as well as Estonia and Lithuania are collected and integrated into modelling system. For example data form more then 40 thousands wells are directly used to automatically generate the geological structure of the model. Additionally a groundwater sampling campaign is undertaken. Contents of CFC, stabile isotopes of O and H and radiocarbon are the most significant parameters of groundwater that are established in unprecedented scale for Latvia. The most important modelling results will be published in web as a data set. Project number: 2009/0212/1DP/1.1.1.2.0/09/APIA/VIAA/060. Project web-site: www.puma.lu.lv

  1. Jurassic sedimentary basins in the Central Asian orogenic belt

    SciTech Connect

    Bebeshev, I.I.

    1995-05-01

    The principal stages of development of Jurassic sedimentary basins (from their origin to the end of their existence) in the Central Asian orogenic belt are considered. The interrelations of the basins with the surrounding paleorises are investigated. Paleogeographic maps are compiled representing the evolution of paleolandscapes and revealing their interrelations in space and time for each stage. Areas with the highest prospects for coal are found.

  2. Geodynamic evolution of early Mesozoic sedimentary basins in eastern Australia

    NASA Astrophysics Data System (ADS)

    Rosenbaum, G.; Babaahmadi, A.; Esterle, J.

    2014-12-01

    Eastern Australia is covered by a series of continental sedimentary basins deposited during the Triassic and Jurassic, but the geodynamic context of these basins is not fully understood. Using gridded aeromagnetic data, seismic reflection data, geological maps, digital elevation models, and field observations, we conducted a structural synthesis aimed at characterizing major structures and deformation style in the Triassic-Jurassic sedimentary basins of eastern Australia. Our results show evidence for four alternating episodes of rifting and contractional events during the Triassic. Two major episodes of rifting, characterized by syn-sedimentary steep normal faults and bimodal volcanism, resulted in the development of the Early-Middle Triassic Esk-Nymboida Rift System and the early Late Triassic Ipswich Basin. Faults in the Esk-Nymboida Rift System have been controlled by a pre-existing oroclinal structure. Each phase of rifting was followed by a contractional event, which produced folds, reverse faults and unconformities in the basins. Since the latest Late Triassic, thermal subsidence led to the deposition of continental sediments in the Clarence-Moreton Basin, which continued until the Early Cretaceous. We suggest that the geodynamic control on the alternating episodes of rifting and contraction during the Triassic in eastern Australia was ultimately related to plate boundary migration and switches between trench retreat and advance.

  3. Fluvial geomorphic elements in modern sedimentary basins and their potential preservation in the rock record: A review

    NASA Astrophysics Data System (ADS)

    Weissmann, G. S.; Hartley, A. J.; Scuderi, L. A.; Nichols, G. J.; Owen, A.; Wright, S.; Felicia, A. L.; Holland, F.; Anaya, F. M. L.

    2015-12-01

    Since tectonic subsidence in sedimentary basins provides the potential for long-term facies preservation into the sedimentary record, analysis of geomorphic elements in modern continental sedimentary basins is required to understand facies relationships in sedimentary rocks. We use a database of over 700 modern sedimentary basins to characterize the fluvial geomorphology of sedimentary basins. Geomorphic elements were delineated in 10 representative sedimentary basins, focusing primarily on fluvial environments. Elements identified include distributive fluvial systems (DFS), tributive fluvial systems that occur between large DFS or in an axial position in the basin, lacustrine/playa, and eolian environments. The DFS elements include large DFS (> 30 km in length), small DFS (< 30 km in length), coalesced DFS in bajada or piedmont plains, and incised DFS. Our results indicate that over 88% of fluvial deposits in the evaluated sedimentary basins are present as DFS, with tributary systems covering a small portion (1-12%) of the basin. These geomorphic elements are commonly arranged hierarchically, with the largest transverse rivers forming large DFS and smaller transverse streams depositing smaller DFS in the areas between the larger DFS. These smaller streams commonly converge between the large DFS, forming a tributary system. Ultimately, most transverse rivers become tributary to the axial system in the sedimentary basin, with the axial system being confined between transverse DFS entering the basin from opposite sides of the basin, or a transverse DFS and the edge of the sedimentary basin. If axial systems are not confined by transverse DFS, they will form a DFS. Many of the world's largest rivers are located in the axial position of some sedimentary basins. Assuming uniformitarianism, sedimentary basins from the past most likely had a similar configuration of geomorphic elements. Facies distributions in tributary positions and those on DFS appear to display

  4. Hydrogeologic framework of fractured sedimentary rock, Newark Basin, New Jersey

    USGS Publications Warehouse

    Lacombe, Pierre J.; Burton, William C.

    2010-01-01

    The hydrogeologic framework of fractured sedimentary bedrock at the former Naval Air Warfare Center (NAWC), Trenton, New Jersey, a trichloroethylene (TCE)-contaminated site in the Newark Basin, is developed using an understanding of the geologic history of the strata, gamma-ray logs, and rock cores. NAWC is the newest field research site established as part of the U.S. Geological Survey Toxic Substances Hydrology Program, Department of Defense (DoD) Strategic Environmental Research and Development Program, and DoD Environmental Security Technology Certification Program to investigate contaminant remediation in fractured rock. Sedimentary bedrock at the NAWC research site comprises the Skunk Hollow, Byram, and Ewing Creek Members of the Lockatong Formation and Raven Rock Member of the Stockton Formation. Muds of the Lockatong Formation that were deposited in Van Houten cycles during the Triassic have lithified to form the bedrock that is typical of much of the Newark Basin. Four lithotypes formed from the sediments include black, carbon-rich laminated mudstone, dark-gray laminated mudstone, light-gray massive mudstone, and red massive mudstone. Diagenesis, tectonic compression, off-loading, and weathering have altered the rocks to give some strata greater hydraulic conductivity than other strata. Each stratum in the Lockatong Formation is 0.3 to 8 m thick, strikes N65 degrees E, and dips 25 degrees to 70 degrees NW. The black, carbon-rich laminated mudstone tends to fracture easily, has a relatively high hydraulic conductivity and is associated with high natural gamma-ray count rates. The dark-gray laminated mudstone is less fractured and has a lower hydraulic conductivity than the black carbon-rich laminated mudstone. The light-gray and the red massive mudstones are highly indurated and tend to have the least fractures and a low hydraulic conductivity. The differences in gamma-ray count rates for different mudstones allow gamma-ray logs to be used to correlate and

  5. Permo-Carboniferous sedimentary basins related to the distribution of planetary cryptoblemes

    USGS Publications Warehouse

    Windolph, J.F.

    1997-01-01

    Massive/high velocity solar, galactic, and cosmic debris impacting the Earths surface may account for the enormous energy required for the formation of Permo-Carboniferous sedimentary basins and related mountain building orogenies. Analysis of satellite immagry, sea floor sonar, geophysical data, and geotectonic fabrics show a strong correlation throughout geologic time between sedimentary basin origin and planetary cryptoblemes. Cryptoblemes are subtile, multi-ringed, radial centric impact shock signatures covering the entire terrestrial surface and ocean floors, having a geometry and distribution strikingly similar to the surfaces of the lunar planetary bodies in the solar system. Investigations of Permo-Carboniferous basins show an intensely overprinted pattern of cryptoblemes coinciding with partial obliteration and elliptical compression of pre-existing basins and accompanying shock patterns. Large distorted cryptoblemes may incorporate thin skin deformation, localized sediment diagenesis, regional metamorphism, and juxtaposed exotic terrains. These data, related to basin morphogenic symmetry, suggest that large episodic impact events are the primary cause of tectonogenic features, geologic boundary formation and mass extinction episodes on the planet Earth. Plate tectonics may be only a slow moving, low energy secondary effect defined and set in motion by megacosmic accretion events. Permo-Carboniferous sediments of note are preserved or accumulated in relatively small rectangular to arcuate rift valleys and synclinal down warps, such as the Narraganset basin of Massachusetts, USA, and Paganzo basin in Argentina, S.A. These deposits and depocenters may originate from dynamic reinforcement/cancellation impact effects, as can be seen in the Basin Range of Nevada and Utah, USA. Large circular to oval sedimentary basins commonly include internal ring structures indicating post depositional subsidence and rebound adjustments with growth faulting, notable in the

  6. Estimating tectonic history through basin simulation-enhanced seismic inversion: geoinfomatics for sedimentary basins

    NASA Astrophysics Data System (ADS)

    Tandon, Kush; Tuncay, Kagan; Hubbard, Kyle; Comer, John; Ortoleva, Peter

    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

  7. 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

  8. Strong motion from surface waves in deep sedimentary basins

    USGS Publications Warehouse

    Joyner, W.B.

    2000-01-01

    It is widely recognized that long-period surface waves generated by conversion of body waves at the boundaries of deep sedimentary basins make an important contribution to strong ground motion. The factors controlling the amplitude of such motion, however, are not widely understood. A study of pseudovelocity response spectra of strong-motion records from the Los Angeles Basin shows that late-arriving surface waves with group velocities of about 1 km/sec dominate the ground motion for periods of 3 sec and longer. The rate of amplitude decay for these waves is less than for the body waves and depends significantly on period, with smaller decay for longer periods. The amplitude can be modeled by the equation log y = f(M, RE) + c + bRB where y is the pseudovelocity response, f(M, RE) is an attenuation relation based on a general strong-motion data set, M is moment magnitude, RE is the distance from the source to the edge of the basin, RB is the distance from the edge of the basin to the recording site, and b and c are parameters fit to the data. The equation gives values larger by as much as a factor of 3 than given by the attenuation relationships based on general strong-motion data sets for the same source-site distance. It is clear that surface waves need to be taken into account in the design of long-period structures in deep sedimentary basins. The ground-motion levels specified by the earthquake provisions of current building codes, in California at least, accommodate the long-period ground motions from basin-edge-generated surface waves for periods of 5 sec and less and earthquakes with moment magnitudes of 7.5 or less located more than 20 km outside the basin. There may be problems at longer periods and for earthquakes located closer to the basin edge. The results of this study suggest that anelastic attenuation may need to be included in attempts to model long-period motion in deep sedimentary basins. To obtain better data on surface waves in the future

  9. The sedimentary and crustal velocity structure of Makarov Basin and adjacent Alpha Ridge

    NASA Astrophysics Data System (ADS)

    Evangelatos, John; Funck, Thomas; Mosher, David C.

    2017-01-01

    This study examines the velocity structure of Makarov Basin and the adjacent Alpha Ridge to determine the tectonic origins of these features and link them to the larger Amerasia Basin. Seismic data from sonobuoys distributed along a 650 km-long line extending from Alpha Ridge and across Makarov Basin to the Lomonosov Ridge were analyzed for this purpose. Forward modelling of traveltimes, supported by coincident multi-channel seismic reflection and shipborne gravity data, were used to determine the P-wave velocity structure along the line. The sedimentary cover averages 0.5 km-thick on Alpha Ridge and 1.9 km-thick in Makarov Basin, but reaches up to 5 km-thick at the base of Lomonosov Ridge. Velocities in the sedimentary section range from 1.6 to 4.3 km s- 1. As suggested by relatively high velocities, interbedded volcaniclastic or volcanic rock may occur in the deep sedimentary section. The shallow basement of Alpha Ridge (3.3 to 3.6 km s- 1) is characterized by semi-continuous high amplitude reflections and is interpreted as volcanic rock possibly intercalated with sedimentary rock. Velocities do not vary significantly in the upper and mid-crustal layers between Alpha Ridge and Makarov Basin. Total crustal thickness decreases from 27 km beneath Alpha Ridge to 5 km-thick in Makarov Basin then thickens to > 20 km over a short distance as part of Lomonosov Ridge. The crustal structure of Alpha Ridge is consistent with previous studies suggesting that the Alpha-Mendeleev ridge complex is part of a large igneous province (LIP) with thick igneous crust. The lack of change in crustal velocities between Alpha Ridge and Makarov Basin suggests that the basin, at least partly, either formed during or was influenced by LIP-related magmatism. The rapid transition of crustal thicknesses from Makarov Basin to Lomonosov Ridge supports the interpretation that this section of the ridge is a transform margin.

  10. Self-Organized Megastructures in Sedimentary Basins

    SciTech Connect

    Peter J. Ortoleva

    2004-06-30

    The overall theme of the project is to develop a quantitative understanding of basin reaction/transport/mechanical (RTM) processes on a broad range of scales. Our approach starts with the development of novel formulations of the basic RTM process rate laws (e.g. rock deformation, texture dynamics, and fracturing). We then set forth algorithms for solving the resulting partial differential equations numerically. As many of the parameters in the subsurface are not well known, we embed the entire approach in a probabilistic framework through information theory. The result is a set of novel software and conceptual papers that have been the first quantitative theory of a number of fundamental phenomena that take into account the full RTM dynamics of these systems.

  11. Exploration matrix evaluation of sedimentary basins of Colombia

    SciTech Connect

    Kanes, W.H.; Bueno, R.

    1989-03-01

    The sedimentary basins of Colombia are evaluated for the following five exploration criteria: (1) source rock potential, including total organic carbon, Rock-Eval analysis, and kerogen types; (2) seals, with specific units and lithologies designated in each basin; (3) reservoirs characteristics, with stress laid on porosity and permeability fairways developed in the various types of clastic depositional systems; (4) traps, whether structural or stratigraphic, and the most probable routes of hydrocarbon migration; and (5) timing, which also examines the interrelationship between maturation and expulsion of hydrocarbon and the formation of the structural or stratigraphic trap and seal. The exploration matrix is based on delineating the play concepts (up to five) for each sedimentary basin. These play concepts are based on a linear scale based on the probability of future or potential discoveries. All data for the analyses were provided by Ecopetrol and were subjectively weighed only where the number of wells in the basin was low in contrast to the basin area (<1:100 km/sup 2/) and there was no history of production.

  12. Sedimentary basin framework of Exmouth Plateau, northwest Australia

    SciTech Connect

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

    1987-05-01

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

  13. Multilayered aquifer modeling in the coastal sedimentary basin of Togo

    NASA Astrophysics Data System (ADS)

    Gnazou, M. D. T.; Sabi, B. E.; Lavalade, J. L.; Schwartz, J.; Akakpo, W.; Tozo, A.

    2017-01-01

    This work is a follow up to the hydrogeological synthesis done in 2012 on the coastal sedimentary basin of Togo. That synthesis notably emphasized the lack of piezometric monitoring in the last thirty years. This has kept us from learning about the dynamics and evolution of the resource in the context of rapidly increasing demand. We are therefore presenting a model for understanding flows, and its main objectives are to provide an initial management tool that should evolve with time as new data (piezometric monitoring, pumping tests, etc.) become available, and to determine what new information can be obtained that will help policy makers to manage the resource better. The results of steady state flow calibration have shown that the aquifer of the Continental Terminal overexploited in the West, can still be exploited in the East of the basin, the Maastrichtian on the whole basin. On the other hand, exploitation of Paleocene aquifers should be done with care.

  14. Sedimentary fill and stratigraphic traps of Porcupine basin, offshore Ireland

    SciTech Connect

    Macurda, D.B. Jr.

    1986-05-01

    The Porcupine basin, off the southwest coast of Ireland, is a triangular north-south re-entrant into the present-day continental shelf. This aulacogen was formed in the Jurassic during the opening of the North Atlantic. A seismic stratigraphic investigation of the southern part of the basin has shown the complex evolution of the sedimentary fill from shallow to deep water facies, resulting in several stratigraphic traps. The central axis of the basin is dominated by a volcanic ridge. Part of the early sedimentary fill was intermittently covered by volcanic flows. The final stage of thin initial siliciclastic infill was the development of an extensive alluvial fan or fan-delta complex along the eastern basin margin. Aerially extensive carbonate sedimentation occurred during the Cretaceous, including a north-south reef tract more than 20 km wide in the eastern part of the basin. Increased subsidence resulted in the deposition of deep water siliciclastics in the Tertiary. The most prominent of these is a series of lower Tertiary submarine fans that were sourced from the western, northern, and eastern margins of the aulacogen. The early portions of the fans correlate well basin-wide; their later history is much more complex, with younger lobes up to 25 km wide developing south of their precursors. Subsequent onlap fill deposits provide an excellent seal. Sedimentation in the late Tertiary has included both high-energy and low-energy deep water deposits. The complex fill of the aulacogen has set up several stratigraphic plays, including carbonate reefs, alluvial fans of fan deltas, and submarine fans. Seismic amplitude anomalies in the latter suggest the heat flow has been sufficient to generate hydrocarbons to fill some of the traps.

  15. Buried Proterozoic foredeep under the Western Canada Sedimentary Basin?

    NASA Astrophysics Data System (ADS)

    Boerner, D. E.; Kurtz, R. D.; Craven, J. A.; Rondenay, S.; Qian, W.

    1995-04-01

    Electromagnetic studies of the Precambrian basement beneath the Western Canada Sedimentary Basin in Alberta indicate a narrow linear conductivity anomaly spatially correlated with a strong positive magnetic feature, the Red Deer high. The conductor is located below sedimentary cover near the top of the crystalline basement and has limited depth extent. We propose that this anomalous feature represents graphitic metasedimentary rocks in the euxinic-flysch facies of a Proterozoic foredeep sequence. The strong magnetic anomaly results from an associated iron formation deposited on the outer ramp of the foredeep. This model explains the geophysical anomalies, has analogues on the exposed shield, and is consistent with the timing, deformation history, and known geology of the Precambrian basement.

  16. Sedimentary basin analysis using airborne gravity data: a case study from the Bohai Bay Basin, China

    NASA Astrophysics Data System (ADS)

    Li, Wenyong; Liu, Yanxu; Zhou, Jianxin; Zhou, Xihua; Li, Bing

    2016-11-01

    In this paper, we discuss the application of an airborne gravity survey to sedimentary basin analysis. Using high-precision airborne gravity data constrained by drilling and seismic data from the Bohai Bay Basin in eastern China, we interpreted faults, structural elements, sedimentary thickness, structural styles and local structures (belts) in the central area of the Basin by the wavelet transform method. Subsequently, these data were subtracted from the Bouguer gravity to calculate the residual gravity anomalies. On this basis, the faults were interpreted mainly by linear zones of high gravity gradients and contour distortion, while the sedimentary thicknesses were computed by the Euler deconvolution. The structural styles were identified by the combination of gravity anomalies and the local structures interpreted by the first vertical derivative of the residual gravity. The results showed evidence for seven faults, one sag and ten new local structure belts.

  17. Walled Sedimentary Basins of China: Perpetrators or Victims of Plateau Growth?

    NASA Astrophysics Data System (ADS)

    Carroll, A. R.; Graham, S. A.; Smith, M. E.

    2004-12-01

    Western China and adjacent areas of central Asia are characterized by low relief, internally drained sedimentary basins that are divided by actively uplifting mountain ranges. The margins of these basins often show evidence for extensive contractional deformation, yet their interiors are surprisingly stable. Basins such as the Tarim and Junggar also exhibit long and apparently continuous histories of closed drainage in the same approximate location (over 250 my in the case of Junggar). In contrast to traditional foreland basins, these basins are not uniquely associated with a specific thrust belt, nor do they show evidence for underlying decollements. We therefore propose the new term "walled basin", in recognition of the essential role of peripheral orogenic walls in creating and maintaining closed drainage and impounding sediments. Walled basins in Asia currently are restricted to areas that receive less than 40 cm/yr precipitation, suggesting that aridity plays a role in preventing fluvial breach of the basin walls (cf., Sobel et al., 2003). Entrapment of sediment within the closed Qaidam basin in the northeast Tibetan plateau has been implicated as a potential mechanism of plateau growth, based on the observations that the basin retains mass within the orogen and creates level topography. However, we propose that the Qaidam instead represents a walled basin that has been elevated due to underplating of the plateau, and is fated to eventual destruction as deformation continues. Several lines of reasoning support this conclusion. First, DEM analysis shows that modern drainage divides for the Qaidam and other walled basins never rise more than 1-2 km above the basin floors, limiting the amount of possible topgraphic infill. Second, the Tarim and Junggar basins presently remain well below 2000 m and probably have never been higher, despite receiving large influxes of detritus from adjacent ranges. Third, the Qaidam basin, like the Tarim and Junggar basins, has an

  18. Research into surface wave phenomena in sedimentary basins

    NASA Astrophysics Data System (ADS)

    Wojcik, G. L.; Isenberg, J.; Ma, F.; Richardson, E.

    1981-12-01

    This study is a continuation of an engineering seismology research effort prompted by the sensitivity of guidance sets in Minuteman Wing V to distant earthquakes. An earlier report considers the probable cause of anomalous patterns of seismic alarms triggered by two North American earthquakes. This report extends the previous study by examining the propagation of surface waves from the 1975 Pocatello Valley, Idaho earthquake sequence across Wyoming to Wing V. In addition, the more general question of surface wave phenomena in sedimentary basins is addressed, particularly the effect of laterally inhomogeneous (dipping) basin-bedrock interfaces. Findings indicate that fundamental and first overtone surface waves are significantly modified by the travel path. In contrast, higher modes are relatively unchanged by the travel path, and affect Wing V in much the same way as body waves considered in the previous study.

  19. Sedimentary basins reconnaissance using the magnetic Tilt-Depth method

    USGS Publications Warehouse

    Salem, A.; Williams, S.; Samson, E.; Fairhead, D.; Ravat, D.; Blakely, R.J.

    2010-01-01

    We compute the depth to the top of magnetic basement using the Tilt-Depth method from the best available magnetic anomaly grids covering the continental USA and Australia. For the USA, the Tilt-Depth estimates were compared with sediment thicknesses based on drilling data and show a correlation of 0.86 between the datasets. If random data were used then the correlation value goes to virtually zero. There is little to no lateral offset of the depth of basinal features although there is a tendency for the Tilt-Depth results to be slightly shallower than the drill depths. We also applied the Tilt-Depth method to a local-scale, relatively high-resolution aeromagnetic survey over the Olympic Peninsula of Washington State. The Tilt-Depth method successfully identified a variety of important tectonic elements known from geological mapping. Of particular interest, the Tilt-Depth method illuminated deep (3km) contacts within the non-magnetic sedimentary core of the Olympic Mountains, where magnetic anomalies are subdued and low in amplitude. For Australia, the Tilt-Depth estimates also give a good correlation with known areas of shallow basement and sedimentary basins. Our estimates of basement depth are not restricted to regional analysis but work equally well at the micro scale (basin scale) with depth estimates agreeing well with drill hole and seismic data. We focus on the eastern Officer Basin as an example of basin scale studies and find a good level of agreement between previously-derived basin models. However, our study potentially reveals depocentres not previously mapped due to the sparse distribution of well data. This example thus shows the potential additional advantage of the method in geological interpretation. The success of this study suggests that the Tilt-Depth method is useful in estimating the depth to crystalline basement when appropriate quality aeromagnetic anomaly data are used (i.e. line spacing on the order of or less than the expected depth to

  20. Seismic interaction between a building network and a sedimentary basin

    NASA Astrophysics Data System (ADS)

    Kham, M.; Semblat, J. F.; Bard, P. Y.; Gueguen, P.

    2003-04-01

    The classical procedure to assess the seismic risk for a superficial structure consists in distinguishing firstly the characterization of the seismic hazard and secondly the analysis of the structure vulnerability. But, as far as the entire urban area is concerned by the seismic risk, a network of superficial structures may influence the free-field motion. In this way, convergent observations were made during the 1985 Mexico earthquake where the large increase in duration may not be completely explained only by site effects. This phenomenon involving the interaction between a city and the sedimentary basin is called Site-City Interaction (SCI) and was firstly underlined by Gueguen [1] in Volvi european test site. Under seismic excitation, the energy radiated by the city back into the soil seems to be mainly controlled by the eigenfrequency ratio fB/fs between the buildings and the soil as well as the urban density. Nevertheless, the key parameters supporting or controlling the SCI effect mainly remain unknown. This point is all the more obvious since present studies on the issue suffer a lack of experimental data characterizing the "urban free field". In the present work, we aim to quantify the specific role of some parameters characterizing the city on seismic hazard modification, such as the urban density, the resonance frequency of the buildings in the city, its homogeneity level (one or several types of different buildings) or the periodicity (or not) of the buildings distribution. To this purpose, a boundary element model is considered which comprises alluvial layers over a rigid elastic basement and superficial buildings. Impedance contrast is taken to 5 in order to support the trapping of the incident energy inside the superficial layers. The whole system is then submitted to a Ricker signal which frequency is successively adjusted to the city and the soil fundamental frequencies. The case of Nice city (France) over a two dimensional basin is then considered

  1. Tectonosedimentary history of the sedimentary basins in northern west Siberia

    SciTech Connect

    Kunin, N.Ya.; Segalovich, I.E. )

    1993-09-01

    Sedimentary basins of northern west Siberia belong to the Arctic tectonosedimentary province. This basin evolved dissimilarly compared to those in the Urengoy and more southern areas, which resulted in substantial differences in the geologic characteristics. Seismic surveys indicate that the basement surface in northern west Siberia occurs at great depths, in places exceeding 15 km. The depressions of the basement surfaces are filled with the thick Paleozoic and Mesozoic sequences. The paper discussed the results of seismostratigraphic analysis of more than 13,000 km of regional common-depth-point profiles. These profiles identified systems of east-west-trending and isometric structures in the region. Some of the structures are buried; others are mapped in the upper horizons of the sedimentary cover and decrease in magnitude with depth. Cretaceous marine sediments that were deposited under deep-water conditions and did not compensate for the tectonic subsidence are widely present in the region. Noncompensated sedimentation was the longest from the Late Jurassic to the Hauterivian-Barremian on the Gydan peninsula and in adjacent areas. The Jurassic section is dominate by ingressive marine sediments. Sediments that did not compensate for tectonic subsidence widely occurred in the Early Jurassic and resulted in deposition of petroleum source rocks. Triassic and Jurassic strata occur conformable in most of northern west Siberia. Significant deformation of the Triassic sediments are identified in the periphery of the Triassic marine basin. This indicates that surrounding structures were thrust against northern west Siberia at the Triassic and Jurassic time boundary. Isometric structures of high magnitude were formed during the Paleozoic structure stage and these structures continued to grow through the Triassic and Jurassic. These and other results of seismostratigraphic analysis suggest the high oil potential of the region.

  2. Plio-Pleistocene drainage development in an inverted sedimentary basin: Vera basin, Betic Cordillera, SE Spain

    NASA Astrophysics Data System (ADS)

    Stokes, Martin

    2008-08-01

    The Vera basin is one of a series of interconnected Neogene-Quaternary sedimentary basins located within the Internal Zone of the Betic Cordillera (southeast Spain). Since the Pliocene the Vera basin has been subjected to low uplift rates (11-21 m Ma - 1 ) and inverted via compressive tectonics that are related to the ongoing oblique collision between the African and Iberian plates. Within this paper the sedimentary and geomorphic response to basin inversion is explored. Sedimentary processes and environments are established for key stratigraphic units of the Pliocene/Plio-Pleistocene basin fill and Pleistocene dissectional landscape. These data are subsequently utilised to reconstruct an evolving basin palaeogeography. Fault and uplift data are employed to discuss the role of tectonically driven basin inversion for controlling the resultant palaeogeographic changes and associated patterns of drainage development. During the Early-Mid Pliocene the Vera basin was characterised by shallow marine shelf conditions (Cuevas Formation). A major palaeogeographic reorganisation occurred during the Mid-Late Pliocene. Strike-slip movement along the eastern basin margin, coupled with uplift and basin emergence created a protected, partially enclosed marine embayment that was conducive for Gilbert-type fan-delta sedimentation from fluvial inputs along the northern and eastern basin margins (Espíritu Santo Formation). The Vera basin then became fully continental and internally drained through the development of a consequent drainage network that formed following the withdrawal of marine conditions during the Late Pliocene to Early Pleistocene. Alluvial fans developed along the northern and western basin margins, grading to a bajada and terminating in a playa lake in central basin areas (Salmerón Formation). During the Early-Mid Pleistocene a switch from basin infilling to dissection took place, recorded by alluvial fan incision, a switch to braided river sedimentation and

  3. The thermal stability of organic acids in sedimentary basins

    SciTech Connect

    Crossey, L.J. )

    1991-03-01

    Water-soluble organic compounds in subsurface brines directly affect the evolution of porosity and permeability during sedimentary diagenesis. Recent examination of the aqueous thermal degradation of oxalic acid (a naturally occurring dicarboxylic acid) and its anions has implications for the thermal stability of dicarboxylic acids under sedimentary basin conditions. Because the thermal stability of these compounds is pH-dependent, consideration of the dissociation behavior of carboxylic acids as a function of temperature is essential for estimating the longevity of difunctional carboxylic acids. Results of burial history models suggest that dicarboxylic acid species may be long-lived in formation waters. Comparison with other experimental studies of carboxylic acids and their anion indicates that acetate stability is greater than formate stability, which is greater than oxalate stability, which is greater than gallate and malonate stability. In addition to the implications of natural systems, the aqueous degradation behavior is critical in evaluating other types of experimental results; notably mineral dissolution studies performed at elevated temperatures in the presence of organic materials and hydrous pyrolysis experiments involving kerogens.

  4. M7+ Virtual Earthquakes near Kanto Sedimentary Basin

    NASA Astrophysics Data System (ADS)

    Denolle, M.; Boué, P.; Hirata, N.; Nakagawa, S.; Miyake, H.; Beroza, G. C.

    2015-12-01

    The Tokyo Metropolitan area is subject to high earthquake activity due to its location near the complex junction of three plates. The seismic hazard Tokyo faces is amplified because it lies in the Kanto basin. The Itoigawa-Shizuoka Tectonic Line (ISTL) is one of the crustal fault zones that comprise these plate boundaries. The ISTL accommodates plate motion between the North American Plate and the Eurasian Plate, hosts oblique-strike slip earthquakes with magnitudes greater than 7, and is only ~ 150-200km away from Tokyo. It is thought to be at a mature stage in its seismic cycle, and predicting strong ground motion from earthquakes on it is important for seismic hazard assessment. We take advantage of the dense seismic network MeSO-net (MEtropolitan Seismic Observation network) and of the locations of the Hi-net (High Sensitivity Seismograph network) stations near the ISTL fault to build virtual earthquakes from the ambient seismic field. First, we construct the Earth's impulse responses from deconvolution of the ambient seismic field recorded between Hi-net stations (as sources) and MeSO-net stations (as receivers) with a method that preserves the relative amplitudes of the response. Fundamental and higher modes are often excited in sedimentary basins and we isolate them in the waveforms through phase velocity analysis in the frequency-wavenumber domain. The virtual earthquake approach turns each station-source near the fault into a double-couple point source by correcting the 9-component impulse response for source depth and mechanism. We use recordings of the M6.7 Northern Nagano earthquake that occurred on November 22, 2014 at the northern end of the fault segment to calibrate absolute amplitudes. We estimate the long period (1-10 seconds) ground motions for a suite of of M7+ scenario ruptures on the ISTL and explore the role of waveguides, basin resonance, and basin edges in strong ground motion.

  5. Modeling Variable-Density Fluid Flow and Solute Transport in Glaciated Sedimentary Basins

    NASA Astrophysics Data System (ADS)

    McIntosh, J. C.; Garven, G.; Hanor, J. S.

    2005-12-01

    Sedimentary basins typically contain saline formation waters (35 to >250 g/L TDS) with relatively long residence times (Kyrs to Myrs). Advance and retreat of km-thick ice sheets, as recently as the Late Pleistocene (<18 ka BP), exposed regional aquifers along the margins of northern latitude basins. Overpressuring of aquifers beneath the wet-based glaciers forced meltwaters to great depths in subsurface flow systems, significantly diluting remnant saline fluids and reorganizing salinity structures. Permafrost zones outboard of the ice sheet margins further enhanced deep circulation of glacial recharge. In basins containing shallow evaporites, meltwaters dissolved large quantities of halite, generating relatively recent (<1 Ma) NaCl brines. Furthermore, glacial recharge promoted generation of economic deposits of microbial methane in shallow organic-rich sediments. To better constrain the impact of glaciation on variable-density fluid flow and solute transport in sedimentary basins, we constructed a transient 2D finite element model of the northern half of the glaciated Michigan Basin. The circular basin is relatively tectonically undeformed and contains ~4 km of Paleozoic strata, primarily composed of carbonates, clastics and bedded evaporites. Thick glacial drift deposits (up to ~300 m) form most of the topographic relief in this low-lying intracratonic region. The salinity of basin fluids sharply increases from <0.5 g/L TDS near the surface to >350 g/L at ~800 m depth. Modern groundwater flow is primarily restricted to shallow glacial drift aquifers, with discharge to the Great Lakes. During Pleistocene glaciation, however groundwater flow patterns were reversed, and meteoric waters were routed into Paleozoic carbonate and siliclastic basinal aquifer systems, depressing the freshwater-saline water mixing zones and dissolving halite. Dilute waters (<100 g/L TDS) migrated ~200 km laterally into the Devonian carbonate aquifers. Carbon-14 ages and δ18O values of

  6. Ground Motion Prediction Atop Geometrically Complex Sedimentary Basins - The Dead Sea Basin

    NASA Astrophysics Data System (ADS)

    Shani-Kadmiel, S.; Tsesarsky, M.; Louie, J. N.; Gvirtzman, Z.

    2014-12-01

    The Dead Sea Transform (DST) is the source for some of the largest earthquakes in the eastern Mediterranean. Several deep and structurally complex sedimentary basins are associated with the DST. These basins are up to 10 km deep and typically bounded by active fault zones. The low seismicity of the DST combined with the limited instrumental coverage of the seismic network in the area result in a critical knowledge gap. Therefore, it is necessary to complement the limited instrumental data with synthetic data based on computational modeling, in order to study the effects of earthquake ground motion in these sedimentary basins. We performed a 2D ground-motion analysis in the Dead Sea Basin (DSB) using a finite-difference code. Results indicate a complex pattern of ground motion amplification affected by the geometric features in the basin. To distinguish between the individual contributions of each geometrical feature in the basin, we developed a semiquantitative decomposition approach. This approach enabled us to interpret the DSB results as follows: (1) Ground-motion amplification as a result of resonance occurs basin-wide due to a high impedance contrast at the base of the uppermost layer; (2) Steep faults generate a strong edge-effect that further ampli- fies ground motions; (3) Sub-basins cause geometrical focusing that may significantly amplify ground motions; and (4) Salt diapirs diverge seismic energy and cause a de- crease in ground-motion amplitude. We address the significance of ground motion amplification due to geometrical focusing via an analytical and numerical study. We show that effective geometrical focusing occurs for a narrow set of eccentricities and velocity ratios, where seismic energy is converged to a region of ±0.5 km from surface. This mechanism leads to significant ground motion amplification at the center of the basin, up to a factor of 3; frequencies of the modeled spectrum are amplified up to the corner frequency of the source.

  7. Combining electromagnetic measurements in the Mygdonian sedimentary basin, Greece

    NASA Astrophysics Data System (ADS)

    Autio, U.; Smirnov, M. Yu.; Savvaidis, A.; Soupios, P.; Bastani, M.

    2016-12-01

    We present a novel approach where time-domain electromagnetic (TEM) data are transformed and subsequently used in two-dimensional (2-D) magnetotelluric inversion of the determinant of the impedance tensor. The main idea is to integrate TEM with magnetotelluric (MT) data to produce subsurface electrical resistivity models. Specifically, we show that 2-D MT data inversion of the determinant of the impedance tensor supported by inclusion of TEM-MT-transformed data has superior resolution at the near surface and at the same time static shift afflicting the MT data can be addressed. Thus, the approach allows for practical express integration of TEM data with MT measurements as opposed to a full combined 3-D inversion, which requires significant resources. The approach is successfully applied in the Mygdonian sedimentary basin located in Northern Greece. In addition to TEM and MT data, also controlled source - and radiomagnetotelluric data are available from the Mygdonian basin, which have been subjected to 2-D analysis previously. We have extended the analysis to a full 3-D inversion using ModEM code. All obtained models are analysed and are in a good agreement.

  8. Deep injection of waste water in the Western Canada sedimentary basin.

    PubMed

    Ferguson, Grant

    2015-01-01

    Injection of wastes into the deep subsurface has become a contentious issue, particularly in emerging regions of oil and gas production. Experience in other regions suggests that injection is an effective waste management practice and that widespread environmental damage is unlikely. Over the past several decades, 23 km(3) of water has been injected into the Western Canada Sedimentary Basin (WCSB). The oil and gas industry has injected most of this water but large amounts of injection are associated with mining activities. The amount of water injected into this basin during the past century is 2 to 3 orders magnitude greater than natural recharge to deep formations in the WCSB. Despite this large-scale disturbance to the hydrogeological system, there have been few documented cases of environmental problems related to injection wells. Deep injection of waste appears to be a low risk activity based on this experience but monitoring efforts are insufficient to make definitive statements. Serious uncharacterized legacy issues could be present. Initiating more comprehensive monitoring and research programs on the effects of injection in the WCSB could provide insight into the risks associated with injection in less developed sedimentary basins.

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

    NASA Astrophysics Data System (ADS)

    Bahlburg, H.

    2015-12-01

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

  10. Coseismic growth of sedimentary basins along the Yammouneh strike-slip fault (Lebanon)

    NASA Astrophysics Data System (ADS)

    Nemer, Tony; Gomez, Francisco; Al Haddad, Sharbel; Tabet, Charles

    2008-12-01

    The left-lateral Yammouneh fault (YF) is the main active branch of the Dead Sea Transform Fault (DSTF) within the Lebanese restraining bend. Despite the overall transpressional setting, a series of sedimentary basins have developed along the trace of the YF. Consequently, palaeoseismic studies within these basins provide an opportunity to study the processes of coseismic growth of the basins, as well as elucidate earthquake behaviour of the fault, in general. Geodetic measurements of contemporary fault slip within the Lebanese restraining bend indicate that the YF accommodates most of the expected left-lateral strike-slip motion, despite the apparent lack of present-day seismicity. We studied the YF, using combined investigations of remote imagery, geomorphology and palaeoseismology. The active fault trace along a 51 km strip was delineated as relatively young surface ruptures and fault scarps that affect Holocene deposits with intermittent offset geomorphic markers. Seven closed basins that occur along-strike of the YF, were found to be related to faulting, with at least three of them displaying evident pull-apart settings. We concentrated our work on the rhombohedral Yammouneh basin, an actively evolving example of pull-apart basins, which is presently obliquely cut by the active fault, with an apparently young age of 1.4 +/- 0.3 Myr. 3-D correlation and analysis of palaeoseismic investigations exposed a composite shear zone with a total subsidence that exceeds 1.6 m over the past 4000-4400 yr. Stratigraphic and geochronological constraints suggest the occurrences of at least five large faulting events during that period. By correlating the stratigraphy and ages of this trench with a previously published study located nearby, a combined palaeoseismic history for the past five events is constructed. This suggests a mean recurrence period of 1020-1175 yr for large earthquakes along this section of the YF. Our results suggest a subsidence rate due to faulting of

  11. The Lusi eruption and implications for understanding fossil piercement structures in sedimentary basins

    NASA Astrophysics Data System (ADS)

    Svensen, Henrik; Mazzini, Adriano; Planke, Sverre; Hadi, Soffian

    2016-04-01

    The Lusi eruption started in northeast Java, Indonesia, on May 29th 2006, and it has been erupting rocks, mud, water, and gas ever since. We have been doing field work and research on Lusi ever since the eruption commenced. This work was initially motivated from studying the initiation of a mud volcano. However, the longevity of the eruption has made it possible to describe and monitor the lifespan of this unique piercement structure. . One of the first-order questions regarding the eruption is how it should be classified and if there are any other modern or fossil analogues that can place Lusi in a relevant geological context. During the initial stages of eruption, Lusi was classified as a mud volcano, but following geochemical studies the eruption did not show the typical CH4-dominated gas composition of other mud volcanoes and the temperature was also too high. Moreover, mud volcano eruptions normally last a few days, but Lusi never stopped during the past decade. In particular, the crater fluid geochemistry suggests a connection to the neighboring volcanic complex. Lusi represent a sedimentary hosted hydrothermal system. This opens up new possibilities for understanding fossil hydrothermal systems in sedimentary basins, such as hydrothermal vent complexes and breccia-pipes found in sedimentary basins affected by the formation of Large igneous provinces. We will present examples from the Karoo Basin (South Africa) and the Vøring Basin (offshore Norway) and discuss how Lusi can be used to refine existing formation models. Finally, by comparing Lusi to fossil hydrothermal systems we may get insight into the processes operating at depth where the Lusi system interacts with the igneous rocks of the neighbouring volcanic arc.

  12. Inverse modeling of geochemical and mechanical compaction in sedimentary basins

    NASA Astrophysics Data System (ADS)

    Colombo, Ivo; Porta, Giovanni Michele; Guadagnini, Alberto

    2015-04-01

    We study key phenomena driving the feedback between sediment compaction processes and fluid flow in stratified sedimentary basins formed through lithification of sand and clay sediments after deposition. Processes we consider are mechanic compaction of the host rock and the geochemical compaction due to quartz cementation in sandstones. Key objectives of our study include (i) the quantification of the influence of the uncertainty of the model input parameters on the model output and (ii) the application of an inverse modeling technique to field scale data. Proper accounting of the feedback between sediment compaction processes and fluid flow in the subsurface is key to quantify a wide set of environmentally and industrially relevant phenomena. These include, e.g., compaction-driven brine and/or saltwater flow at deep locations and its influence on (a) tracer concentrations observed in shallow sediments, (b) build up of fluid overpressure, (c) hydrocarbon generation and migration, (d) subsidence due to groundwater and/or hydrocarbons withdrawal, and (e) formation of ore deposits. Main processes driving the diagenesis of sediments after deposition are mechanical compaction due to overburden and precipitation/dissolution associated with reactive transport. The natural evolution of sedimentary basins is characterized by geological time scales, thus preventing direct and exhaustive measurement of the system dynamical changes. The outputs of compaction models are plagued by uncertainty because of the incomplete knowledge of the models and parameters governing diagenesis. Development of robust methodologies for inverse modeling and parameter estimation under uncertainty is therefore crucial to the quantification of natural compaction phenomena. We employ a numerical methodology based on three building blocks: (i) space-time discretization of the compaction process; (ii) representation of target output variables through a Polynomial Chaos Expansion (PCE); and (iii) model

  13. Thermal history determined by fission-track dating for three sedimentary basins in California and Wyoming

    USGS Publications Warehouse

    Naeser, Nancy D.

    1984-01-01

    The use of fission-tracks is demonstrated in studies of time-temperature relationships in three sedimentary basins in the western United States; in the Tejon Oil Field area of the southern San Joaquin Valley, California; in the northeastern Green River basin, Wyoming, and in drill holes in the southern Powder River Basin, Wyoming.

  14. Looking for sedimentary basins using global gravity and crustal models

    NASA Astrophysics Data System (ADS)

    Colpani, Stefano; Strykowski, Gabriel

    2014-05-01

    Publically available and newly released global crustal model, CRUST 1.0 (Laske et al., 2013) in combination with satellite based global gravity models GOCO3s (Mayer-Gürr T. et al., 2012) yield a possibility of combining global source models with global gravity models. The depths to the top and to the base of the geological units obtained from the global crust model are used to fix the source geometry. This information is subsequently used to forward compute the global gravity signature of these units in different heights above the sources and for unit mass density. The average global mass density for the geological unit acts like a scaling factor and the relation to the gravity signal becomes linear. The computations are done both for Tz (gravity disturbances) and for some chosen gravity gradient components Tzz, Tzx and Tzy, where x,y and z refer to a local east-north-up Cartesian reference frame. The above setup allows constructing a model of the regional (gravity) field both for Tz and for the above gradient components Tzz, Tzx and Tzy and to improve it on regional scale. In principle, the method allows to keep track of the relation between the regional (gravity) signal and the source model. Subsequently, a generalized Nettleton's method can be used to fine-tune density values for the sediments from any above type of gravity data and a combination of it. Finally, for the well-surveyed areas, the results can be compared with the independent information about the basin geometry. This experience can be used for quantifying the information about the sedimentary basin in areas where the information is limited.

  15. Noise correlation tomography of Southwest Western Canada Sedimentary Basin

    NASA Astrophysics Data System (ADS)

    Gu, Yu Jeffrey; Shen, Luyi

    2015-07-01

    We analyse continuous recordings from 23 broadband seismic stations near Alberta, the southwestern sector of the Western Canada Sedimentary Basin. Noise correlation tomo-graphy based on vertical-component seismograms reveals below-average shear velocities at shallow and middle crustal depths in central Alberta, spanning across Proterozoic accreted terranes and Archean microcontinents. This observation likely results from extensive plate convergence and crustal melting during the Proterozoic eon. The overall correlation between the crustal velocities and presumed basement domains is lower than expected, however. In the lower crust, the main pattern of shear velocities is relatively concordant with the reported domain boundaries and key Precambrian structures appear to be intact. The shear velocities beneath the Loverna Block, the largest constituent of the Hearne craton, are 10 per cent higher than the regional average. This prominent northeast striking seismic anomaly is moderately correlated with the regional heat flow and potentially represents the remnant core of the Archean Hearne province. The associated high velocities extend into the western part of the Medicine Hat Block, a possible Archean microcontinent with a debatable origin, and contribute to a strong east-west structural gradient in the lower crust. The presence and the continuity of this anomalous structure imply extensive communications among the various basement domains in southern Alberta during the assembly of the North American continent.

  16. The potential for free and mixed convection in sedimentary basins

    USGS Publications Warehouse

    Raffensperger, J.P.; Vlassopoulos, D.

    1999-01-01

    Free thermal convection and mixed convection are considered as potential mechanisms for mass and heat transport in sedimentary basins. Mixed convection occurs when horizontal flows (forced convection) are superimposed on thermally driven flows. In cross section, mixed convection is characterized by convection cells that migrate laterally in the direction of forced convective flow. Two-dimensional finite-element simulations of variable-density groundwater flow and heat transport in a horizontal porous layer were performed to determine critical mean Rayleigh numbers for the onset of free convection, using both isothermal and semi-conductive boundaries. Additional simulations imposed a varying lateral fluid flux on the free-convection pattern. Results from these experiments indicate that forced convection becomes dominant, completely eliminating buoyancy-driven circulation, when the total forced-convection fluid flux exceeds the total flux possible due to free convection. Calculations of the thermal rock alteration index (RAI=q????T) delineate the patterns of potential diagenesis produced by fluid movement through temperature gradients. Free convection produces a distinct pattern of alternating positive and negative RAIs, whereas mixed convection produces a simpler layering of positive and negative values and in general less diagenetic alteration. ?? Springer-Verlag.

  17. Understanding Long-Term Solute Transport in Sedimentary Basins: Simulating Brine Migration in the Alberta Basin. Final Report

    SciTech Connect

    Alicia M. Wilson

    2009-11-30

    Mass transport in deep sedimentary basins places important controls on ore formation, petroleum migration, CO2 sequestration, and geochemical reactions that affect petroleum reservoir quality, but large-scale transport in this type of setting remains poorly understood. This lack of knowledge is highlighted in the resource-rich Alberta Basin, where geochemical and hydrogeologic studies have suggested residence times ranging from hundreds of millions of years to less than 5 My, respectively. Here we developed new hydrogeologic models that were constrained by geochemical observations to reconcile these two very different estimates. The models account for variable-density fluid flow, heat transport, solute transport, sediment deposition and erosion, sediment compressibility, and dissolution of salt deposits, including Cl/Br systematics. Prior interpretations of Cl/Br ratios in the Alberta Basin concluded that the brines were derived from evaporatively-concentrated brines that were subsequently diluted by seawater and freshwater; models presented here show that halite dissolution must have contributed strongly as well, which implies significantly greater rates of mass transport. This result confirms that Cl/Br ratios are subject to significant non-uniqueness and thus do not provide good independent indicators of the origin of brines. Salinity and Cl/Br ratios provided valuable new constraints for basin-scale models, however. Sensitivity studies revealed that permeabilities obtained from core- and field-scale tests were appropriate for basin-scale models, despite the differences in scale between the tests and the models. Simulations of groundwater age show that the residence time of porefluids in much of the basin is less than 100 My. Groundwater age increases with depth and approaches 200 My in the deepest part of the basin, but brines are significantly younger than their host rocks throughout the basin.

  18. Space Station Views of African Sedimentary Basins-Analogs for Subsurface Patterns

    NASA Technical Reports Server (NTRS)

    Wilkinson, M. Justin

    2007-01-01

    Views of African sedimentary basins from the International Space Station (ISS) is presented. The images from ISS include: 1) Inland deltas; 2) Prediction; 3) Significance; 4) Exploration applications; and 5) Coastal megafans

  19. Tectono-Sedimentary Analysis of Rift Basins: Insights from the Corinth Rift, Greece

    NASA Astrophysics Data System (ADS)

    Gawthorpe, Robert; Ford, Mary

    2015-04-01

    Existing models for the tectono-sedimentary evolution of rift basins are strongly linked the growth and linkage of normal fault segments and localization of fault activity. Early stages of faulting (rift initiation phase) are characterized by distributed, short, low displacement fault segments, subdued fault-related topography and small depocentres within which sedimentation keeps pace with subsidence. Following linkage and displacement localization (rift climax phase), deformation if focused onto major, crustal-scale fault zones with kilometre-scale displacement. These major faults generate pronounced tilted fault-block topography, with subsidence rates that outpace sedimentation causing a pronounced change to deep-water deposition. Such models have been successful in helping to understand the gross structural and sedimentary evolution of rift basins, but recent work has suggested that pre-existing structures, normal fault interaction with pre-rift salt and antecedent drainage systems significantly alter this initiation-to-climax perspective of rift basin development. The E-W-striking, Pliocene-Pleistocene Corinth rift, central Greece, is an excellent natural laboratory for studying the tectono-sedimentary evolution of rift basins due to its young age, excellent onshore exposure of syn-rift structure and stratigraphy and extensive offshore seismic data. The rift cuts across the NW-SE-striking Hellenide mountain belt and has migrated northward and westward during its evolution. The Hellenide mountain belt significantly influences topography and drainage in the west of the rift. High topography and large antecedent drainage systems, focused along palaeovalleys, provided high sediment flux to NE-flowing alluvial systems that overfilled early-rift depocentres. Further east, away from the main antecedent drainage networks, contemporaneous deposits comprise deep-lacustrine turbidite channel and lobe complexes and basinal marls. Thus the stratigraphic expression within

  20. 3D Inversion of Gravity Anomalies for the Interpretation of Sedimentary Basins using Variable Density Contrast

    NASA Astrophysics Data System (ADS)

    Ekinci, Yunus Levent; Ertekin, Can

    2015-04-01

    Concern about sedimentary basins is generally related to their genetic and economic significance. Analysis of sedimentary basins requires the acquisition of data through outcrop studies and subsurface investigations that encompass drilling and geophysics. These data are commonly analysed by computer-assisted techniques. One of these methods is based on analysing gravity anomalies to compute the depth of sedimentary basin-basement rock interface. Sedimentary basins produce negative gravity anomalies, because they have mostly lower densities than that of the surrounding basement rocks. Density variations in a sedimentary fill increase rapidly at shallower depths then gradually reach the density of surrounding basement rocks due to the geostatic pressure i.e. compaction. The decrease of the density contrast can be easily estimated by a quadratic function. Hence, if the densities are chosen properly and the regional background is removed correctly, the topographical relief of the sedimentary basin-basement rock interface might be estimated by the inversion of the gravity data using an exponential density-depth relation. Three dimensional forward modelling procedure can be carried out by introducing a Cartesian coordinate system, and placing vertical prisms just below observation points on the grid plane. Depth to the basement, namely depths to the bottom of the vertical prisms are adjusted in an iterative manner by minimizing the differences between measured and calculated residual gravity anomalies. In this study, we present a MATLAB-based inversion code for the interpretation of sedimentary basins by approximating the topographical relief of sedimentary basin-basement rock interfaces. For a given gridded residual gravity anomaly map, the procedure estimates the bottom depths of vertical prisms by considering some published formulas and assumptions. The utility of the developed inversion code was successfully tested on theoretically produced gridded gravity data set

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

  2. Lithospheric flexure and sedimentary basin evolution: depositional cycles in the steer's head model

    NASA Astrophysics Data System (ADS)

    Moore, James; Watts, Tony

    2016-04-01

    Backstripping studies of biostratigraphic data from deep wells show that sediment loading is one of the main factors controlling the subsidence and uplift history of sedimentary basins. Previous studies based on single layer models of elastic and viscoelastic plates overlying an inviscid fluid have shown that sediment loading, together with a tectonic subsidence that decreases exponentially with time, can explain the large-scale 'architecture' of rift-type basins and, in some cases, details of their internal stratigraphy such as onlap and offlap patterns. One problem with these so-called 'steer's head' models is that they were based on a simple rheological model in which the long-term strength of the lithosphere increased with thermal age. Recent oceanic flexure studies, however, reveal that the long-term strength of the lithosphere depends not only on thermal age, but also load age. We have used the thermal structure based on plate cooling models, together with recent experimentally-derived flow laws, to compute the viscosity structure of the lithosphere and a new analytical model to compute the flexure of a multilayer viscoelastic plate by a trapezoid-shaped sediment load at different times since basin initiation. The combination of basin subsidence and viscoelastic flexural response results in the fluctuation of the depositional surface with time. If we define the nondimensional number Dw= τm/τt, where τm is the Maxwell time constant and τt is the thermal time constant, we find that for Dw<<1 the flexure approximates that of an elastic plate and is dominated by "onlapping" stratigraphy which evolves through the sedimentary facies with a progressive deepening of the depositional surface. For Dw>>1 the flexure approximates that of a viscoelastic plate and is dominated by "offlapping" stratigraphy, with the basin edges evolving through shallow marine facies; though erosion late in the basin formation prevents much of this from being recorded in the stratigraphy

  3. Tectono-sedimentary history of the Early Liassic basins of the Central High Atlas (Morocco)

    NASA Astrophysics Data System (ADS)

    Quiquerez, A.; Allemand, P.; Sarih, S.; Garcia, J.-P.

    2012-04-01

    The timing of the opening of the Central High Atlas basins (Morocco) is still debated. Previous works have proposed that the tectonics which started in the Triassic was polyphased and that the Early Liassic was characterized by thermal subsidence before a new phase of extension at the beginning of the Toarcian. In order to precise the timing during the Early Liassic, we have documented a syn-rift succession, in the hanging wall of normal fault segment along a 75 km-long transect (Tizi n' Firest fault). Deposits are composed of massive limestones alternating with marl and gravity-flow related deposits. Field observations have been performed on six sections, 5 to 40 km apart. They include both the description of large-scale architecture from satellite image analysis, the identification of carbonate facies from thin sections, the measurements of sediment transport direction, and also the determination of nine time-lines dated by biochronological markers, from the Sinemurian to the Domerian. This fine chronostratigraphic framework has permitted to delineate and correlate 9 stratigraphical units in 6 sites from the Sinemurian to the Domerian. The reconstructions of detailed temporal and spatial sedimentary patterns along the fault have highlighted a high variability of the syn-rift stratigraphy along the normal fault segments. Two main sub-basins have been defined along this transect. The geometry provided by the time-lines showed that the depocenter were located firstly in the west sub-basin, up to the Carixian, and later in the east sub-basin. The central area remained a low preservation domain during the Early Liassic. Most of the transport directions measured is oriented toward the north, indicating the existence of an active topography on the southern limit of the basin at that time. However, some measurements are oriented toward the east, and this mainly during Domerian, possibly indicating slopes orientated in that direction, suggesting asymmetric fault geometry

  4. The tectonic development and erosion of the Knox Subglacial Sedimentary Basin, East Antarctica

    NASA Astrophysics Data System (ADS)

    Maritati, A.; Aitken, A. R. A.; Young, D. A.; Roberts, J. L.; Blankenship, D. D.; Siegert, M. J.

    2016-10-01

    Sedimentary basins beneath the East Antarctic Ice Sheet (EAIS) have immense potential to inform models of the tectonic evolution of East Antarctica and its ice-sheet. However, even basic characteristics such as thickness and extent are often unknown. Using airborne geophysical data, we resolve the tectonic architecture of the Knox Subglacial Sedimentary Basin in western Wilkes Land. In addition, we apply an erosion restoration model to reconstruct the original basin geometry for which we resolve geometry typical of a transtensional pull-apart basin. The tectonic architecture strongly indicates formation as a consequence of the rifting of India from East Gondwana from ca. 160-130 Ma, and we suggest a spatial link with the western Mentelle Basin offshore Western Australia. The erosion restoration model shows that erosion is confined within the rift margins, suggesting that rift structure has strongly influenced the evolution of the Denman and Scott ice streams.

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

    NASA Technical Reports Server (NTRS)

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

    1983-01-01

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

  6. Estimate of the Geothermal Energy Resource in the Major Sedimentary Basins in the United States (Presentation)

    SciTech Connect

    Esposito, A.; Porro, C.; Augustine, C.; Roberts, B.

    2012-09-01

    Because most sedimentary basins have been explored for oil and gas, well logs, temperatures at depth, and reservoir properties such as depth to basement and formation thickness are well known. The availability of this data reduces exploration risk and allows development of geologic exploration models for each basin. This study estimates the magnitude of recoverable geothermal energy from 15 major known U.S. sedimentary basins and ranks these basins relative to their potential. The total available thermal resource for each basin was estimated using the volumetric heat-in-place method originally proposed by (Muffler, 1979). A qualitative recovery factor was determined for each basin based on data on flow volume, hydrothermal recharge, and vertical and horizontal permeability. Total sedimentary thickness maps, stratigraphic columns, cross sections, and temperature gradient information was gathered for each basin from published articles, USGS reports, and state geological survey reports. When published data were insufficient, thermal gradients and reservoir properties were derived from oil and gas well logs obtained on oil and gas commission databases. Basin stratigraphy, structural history, and groundwater circulation patterns were studied in order to develop a model that estimates resource size, temperature distribution, and a probable quantitative recovery factor.

  7. Regional-scale analysis of the geothermal regime in the western Canada sedimentary basin

    SciTech Connect

    Bachu, S. ); Burwash, R.A. )

    1991-01-01

    This paper reports that radiogenic heat generation at the top of the crystalline Precambrian basement underneath the Western Canada Sedimentary Basin is highly variable, on average higher than for the exposed Canadian Shield, and reflects the basement tectonic structure. The areal distribution of the geothermal gradient across the sediments shows a regional-scale northerly increase, with intermediate- and local-state features correlating with anomalies in heat generation at the top of the basement. Only in the northeast and southeast corners of the basin can high geothermal gradients not be explained by heat generation; there they may be caused by convective fluid flow effects. The temperature distribution at the base of the sediments is highly correlated with the thickness of the sedimentary cover and reflects major topographic and basement features. Overall, the characteristics of the geothermal regime in the Western Canada Sedimentary Basin are indicative of a conduction dominated system.

  8. Formation Conditions and Sedimentary Characteristics of a Triassic Shallow Water Braided Delta in the Yanchang Formation, Southwest Ordos Basin, China

    PubMed Central

    Liu, Ziliang; Shen, Fang; Zhu, Xiaomin; Li, Fengjie; Tan, Mengqi

    2015-01-01

    A large, shallow braided river delta sedimentary system developed in the Yanchang Formation during the Triassic in the southwest of the Ordos basin. In this braided delta system, abundant oil and gas resources have been observed, and the area is a hotspot for oil and gas resource exploration. Through extensive field work on outcrops and cores and analyses of geophysical data, it was determined that developments in the Late Triassic produced favorable geological conditions for the development of shallow water braided river deltas. Such conditions included a large basin, flat terrain, and wide and shallow water areas; wet and dry cyclical climate changes; ancient water turbulence; dramatic depth cycle changes; ancient uplift development; strong weathering of parent rock; and abundant supply. The shallow water braided river delta showed grain sediment granularity, plastic debris, and sediment with mature composition and structure that reflected the strong hydrodynamic environment of large tabular cross-bedding, wedge cross-bedding, and multiple positive rhythms superimposed to form a thick sand body layer. The branch river bifurcation developed underwater, and the thickness of the sand body increased further, indicating that the slope was slow and located in shallow water. The seismic responses of the braided river delta reflected strong shallow water performance, indicated by a progradation seismic reflection phase axis that was relatively flat; in addition, the seismic reflection amplitude was strong and continuous with a low angle and extended over considerable distances (up to 50 km). The sedimentary center was close to the provenance, the width of the river was large, and a shallow sedimentary structure and a sedimentary rhythm were developed. The development of the delta was primarily controlled by tectonic activity and changes in the lake level; as a result, the river delta sedimentary system eventually presented a “small plain, big front” character. PMID

  9. Formation Conditions and Sedimentary Characteristics of a Triassic Shallow Water Braided Delta in the Yanchang Formation, Southwest Ordos Basin, China.

    PubMed

    Liu, Ziliang; Shen, Fang; Zhu, Xiaomin; Li, Fengjie; Tan, Mengqi

    2015-01-01

    A large, shallow braided river delta sedimentary system developed in the Yanchang Formation during the Triassic in the southwest of the Ordos basin. In this braided delta system, abundant oil and gas resources have been observed, and the area is a hotspot for oil and gas resource exploration. Through extensive field work on outcrops and cores and analyses of geophysical data, it was determined that developments in the Late Triassic produced favorable geological conditions for the development of shallow water braided river deltas. Such conditions included a large basin, flat terrain, and wide and shallow water areas; wet and dry cyclical climate changes; ancient water turbulence; dramatic depth cycle changes; ancient uplift development; strong weathering of parent rock; and abundant supply. The shallow water braided river delta showed grain sediment granularity, plastic debris, and sediment with mature composition and structure that reflected the strong hydrodynamic environment of large tabular cross-bedding, wedge cross-bedding, and multiple positive rhythms superimposed to form a thick sand body layer. The branch river bifurcation developed underwater, and the thickness of the sand body increased further, indicating that the slope was slow and located in shallow water. The seismic responses of the braided river delta reflected strong shallow water performance, indicated by a progradation seismic reflection phase axis that was relatively flat; in addition, the seismic reflection amplitude was strong and continuous with a low angle and extended over considerable distances (up to 50 km). The sedimentary center was close to the provenance, the width of the river was large, and a shallow sedimentary structure and a sedimentary rhythm were developed. The development of the delta was primarily controlled by tectonic activity and changes in the lake level; as a result, the river delta sedimentary system eventually presented a "small plain, big front" character.

  10. Paleogeographic and paleotectonic setting of sedimentary basins in the Sevier thrust belt and hinterland, eastern Great Basin

    SciTech Connect

    Schmitt, J.G. . Dept. of Earth Sciences); Vandervoort, D.S. . Dept. of Geological Sciences); Suydam, J.D. . Dept. of Geology)

    1993-04-01

    The eastern Great Basin contains a sparse record of broadly distributed Cretaceous sedimentary rocks which record: evolution of intermontane basins during development of the Sevier (Sv)contractional orogen and incipient extensional collapse of the elevated Sv hinterland (east-central NV), and complex tectono-sedimentary interactions between frontal thrust belt structures and the western margin of the adjacent foreland basin. Palinspastic restoration of these strata and associated structures to pre-Tertiary extension positions reveals a clearer pictures of Cretaceous basin paleogeography and allows comparison with the Puna/Altiplano plateau and precordillera thrust belt of the Neogene Andean orogen. Two syntectonic stratal assemblages are present in east-central NV. Lower Cretaceous alluvial strata (Newark Canyon Fm) record basin development coeval with emergence of contractional structures in the Sv hinterland. Localized early Cretaceous basins were possibly piggyback immature; periods of open drainage to the to the east and south suggest connection with the nascent Sv foreland basin to the east (Cedar Mountain/Sanpete Fms) prior to major thrust loading in central Utah. Development of hinterland structures is almost recorded by Aptian-Albian foreland basin alluvial deposits in SW Utah (Dakota Fm) and southern Nevada (Willow Tank Fm). Upper Cretaceous to Eocene strata (Sheep Pass Fm) record inception of regionally abundant alluvial-lacustrine basins which developed in response to onset of latest Cretaceous extension and associated collapse of the Sv hinterland. Evolution of the structurally complex western margin of the Sv foreland basin is recorded in Cretaceous through Eocene strata deposited in: piggyback basins which were at times hydrologically connected to the adjacent foreland basins, and thrust-proximal portions of the foreland basin. These proximal areas are characterized by folding and faulting of basin fill and development of intrabasinal unconformities.

  11. Estimate of Geothermal Energy Resource in Major U.S. Sedimentary Basins (Presentation)

    SciTech Connect

    Porro, C.; Augustine, C.

    2012-04-01

    This study estimates the magnitude of geothermal energy from fifteen major known US sedimentary basins and ranks these basins relative to their potential. Because most sedimentary basins have been explored for oil and gas, well logs, temperatures at depth, and reservoir properties are known. This reduces exploration risk and allows development of geologic exploration models for each basin as well as a relative assessment of geologic risk elements for each play. The total available thermal resource for each basin was estimated using the volumetric heat-in-place method originally proposed by Muffler (USGS). Total sedimentary thickness maps, stratigraphic columns, cross sections, and temperature gradient Information were gathered for each basin from published articles, USGS reports, and state geological survey reports. When published data was insufficient, thermal gradients and reservoir properties were derived from oil and gas well logs obtained on oil and gas commission websites. Basin stratigraphy, structural history, and groundwater circulation patterns were studied in order to develop a model that estimates resource size and temperature distribution, and to qualitatively assess reservoir productivity.

  12. Derivation of S and Pb in phanerozoic intrusion-related metal deposits from neoproterozoic sedimentary pyrite, Great Basin, United States

    USGS Publications Warehouse

    Vikre, P.G.; Poulson, S.R.; Koenig, A.E.

    2011-01-01

    from sedimentary pyrite, and volatiles acquired from deeper crustal or mantle sources. In the central and eastern Great Basin, the wide distribution and high density of small to mid-sized vein, replacement, and skarn intrusion-related metal deposits in lower Paleozoic rocks that contain TDS sedimentary pyrite S and Pb reflect (1) prolific Jurassic, Cretaceous, and Tertiary magmatism, (2) a regional, substrate reservoir of S and Pb in permeable and homogeneous siliciclastic strata, and (3) relatively small scale concentration of substrate and magmatic components. Large intrusion-related metal deposits in the central and eastern Great Basin acquired S and most Pb from thicker lithospheric sections. ?? 2011 Society of Economic Geologists, Inc.

  13. Atmospheric methane from organic carbon mobilization in sedimentary basins — The sleeping giant?

    NASA Astrophysics Data System (ADS)

    Kroeger, K. F.; di Primio, R.; Horsfield, B.

    2011-08-01

    The mass of organic carbon in sedimentary basins amounts to a staggering 10 16 t, dwarfing the mass contained in coal, oil, gas and all living systems by ten thousand-fold. The evolution of this giant mass during subsidence and uplift, via chemical, physical and biological processes, not only controls fossil energy resource occurrence worldwide, but also has the capacity for driving global climate: only a tiny change in the degree of leakage, particularly if focused through the hydrate cycle, can result in globally significant greenhouse gas emissions. To date, neither climate models nor atmospheric CO 2 budget estimates have quantitatively included methane from thermal or microbial cracking of sedimentary organic matter deep in sedimentary basins. Recent estimates of average low latitude Eocene surface temperatures beyond 30 °C require extreme levels of atmospheric CO 2. Methane degassing from sedimentary basins may be a mechanism to explain increases of atmospheric CO 2 to values as much as 20 times higher than pre-industrial values. Increased natural gas emission could have been set in motion either by global tectonic processes such as pulses of activity in the global alpine fold belt, leading to increased basin subsidence and maturation rates in the prolific Jurassic and Cretaceous organic-rich sediments, or by increased magmatic activity such as observed in the northern Atlantic around the Paleocene-Eocene boundary. Increased natural gas emission would have led to global warming that was accentuated by long lasting positive feedback effects through temperature transfer from the surface into sedimentary basins. Massive gas hydrate dissociation may have been an additional positive feedback factor during hyperthermals superimposed on long term warming, such as the Paleocene-Eocene Thermal Maximum (PETM). As geologic sources may have contributed over one third of global atmospheric methane in pre-industrial time, variability in methane flux from sedimentary

  14. Tectono-sedimentary architecture of Marie-Galante basin (Lesser Antilles fore arc)

    NASA Astrophysics Data System (ADS)

    Lebrun, Jean-Frédéric; Cornée, Jean-Jacques; Münch, Philippe; Guennoc, Pol

    2010-05-01

    Marie-Galante basin in the Lesser Antilles fore arc has experienced high amplitude (up to several thousand meters) vertical movements in response to both local tectonic in the fore-arc (trench perpendicular extensional tectonic) and geodynamical events at the plate interface, such as, long term interplate coupling changes, or ridges subduction or alternating period of under-platting/basal erosion... During the KaShallow cruises, we acquired ca. 3500km of high-resolution multichannel seismic reflection data (sparker and miniGI airgun sources), together with HR multibeam bathymetric (50m gridspacing DTM with ±2m depth precision) in the basin and over the shallow-water carbonate platforms surrounding the fore-arc islands. This geophysical dataset completes already existing seismic reflection data of lower resolution but deeper penetration. A systematic rock sampling using piston and rock corers and 2 ROV dives along remarkable cliffs, together with old dredge samples, provided petrological and sedimentary facies description, and datation (radiochronology and Micro/Nanno fossils) of the main stratigraphic series identified in seismic reflection through the basin. The basin divides into 3 sedimentary environments. We identify the architecture of the offshore carbonate platforms around the fore arc island and between them. Seismic profiles reveal the platforms prograding systems at their boundaries. This allows attempting a correlation between all the onshore/offshore archipelago platforms. Particularly, we evidence that the early Pleistocene upper series outcropping onshore extends offshore, and late Pleistocene/Holocene erosional surfaces are revealed. The "deep bassin", gently deepens southeastward from the volcanic arc islands of Basse-Terre and Dominica to the deep (5000m bsl) forearc basin at the accretionnary prism. Seismic profiles reveal the turbiditic infill of the basin. ROV dives permit to sample early Miocene pelagic sediments, and cores sample the late

  15. 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.

  16. Detrital zircon (U-Th)/He thermochronometry in the sedimentary basin and its geological significance

    NASA Astrophysics Data System (ADS)

    Cai, C.; Qiu, N.

    2015-12-01

    The zircon (U-Th)/He thermochronometry has been used as a thermal indicator to study thermal history of the deep sedimentary basin at high temperature. The closure temperature and age of helium are important parameters for the zircon (U-Th)/He thermochronometry. In this paper, the zircon He closure temperature and its influence factors were studied by establishing the evolutionary pattern between zircon He ages and zircon burial depth based on examined zircon He ages of natural borehole samples obtained from the Cenozoic strara in the sedimentary basin. The results show that the zircon He closure temperature of natural samples in the sedimentary basin is approcimately 195℃, higher than the result (183℃) obtain from the thermal simulation experiments. The high He closure temperature resulted from long term radiation damage accumulation and high effective uranium. We also point out that grain radius, He corrected parameter, effective uranium concentration, radiation damage and radiogenic 4He concentration have apparent influence on the zircon He ages. This study is a revaluation of the conventional zircon He closure temperature. Thus, properly understanding the zircon He ages, closure temperature, and its influence factors, zircon (U-Th)/He dating can provide the true explanation of the testing zircon He ages, and has a great guiding significance in the studying of the evolution of source rocks and the process of hydrocarbon accumulation in the deep sedimentary basin.

  17. Resolving the Sedimentary Basin Structure from Oklahoma with Local Receiver Function

    NASA Astrophysics Data System (ADS)

    Zheng, D.; Ni, S.

    2015-12-01

    The teleseismic receiver function is defined as the radial component of P wave being deconvoluted from the vertical component of the earthquakes with magnitude larger than 5.5 at teleseismic distances. It has successfully been applied in resolving the structure of the crust and upper mantle in many regions. The receiver function can also be used to determine the thickness of sedimentary basin. However the corner frequency of the P waves from the teleseismic events (M>5.5) is relatively low and the high frequency content in the teleseismic P waves is attenuated, thus, the teleseismic receiver function is usually not sufficient to reveal details of sedimentary basin structure. Instead, local small earthquake (~ M3) generates P waves of short duration waveforms with high frequency content, which can be used to calculate receiver functions (called local receiver function). As a case study, we study waveform data from local earthquakes in Oklahoma. We first explore feasibility of local receiver function for different magnitude, focal depth, epicentral distance, filtering band and time window length. After local receiver functions are computed, we search the best velocity model to fit the local receiver function waveforms with the Differential Evolution (DE) algorithm which is a global optimization method. We invert the sedimentary basin structure in Oklahoma and find that this method is suitable for other area for the sedimentary basin structure where local seismic waveforms are available.

  18. Assessment of undiscovered conventional oil and gas resources of the Western Canada Sedimentary Basin, Canada, 2012

    USGS Publications Warehouse

    Higley, Debra

    2013-01-01

    The U.S. Geological Survey recently completed a geoscience-based assessment of undiscovered oil and gas resources of provinces within the Western Canada Sedimentary Basin. The Western Canada Sedimentary Basin primarily comprises the (1) Alberta Basin Province of Alberta, eastern British Columbia, and the southwestern Northwest Territories; (2) the Williston Basin Province of Saskatchewan, southeastern Alberta, and southern Manitoba; and (3) the Rocky Mountain Deformed Belt Province of western Alberta and eastern British Columbia. This report is part of the U.S. Geological Survey World Petroleum Resources Project assessment of priority geologic provinces of the world. The assessment was based on geoscience elements that define a total petroleum system (TPS) and associated assessment unit(s). These elements include petroleum source rocks (geochemical properties and petroleum generation, migration, and accumulation), reservoir description (reservoir presence, type, and quality), and petroleum traps (trap and seal types, and timing of trap and seal formation relative to petroleum migration). Using this framework, the Elk Point-Woodbend Composite TPS, Exshaw-Fernie-Mannville Composite TPS, and Middle through Upper Cretaceous Composite TPS were defined, and four conventional assessment units within the total petroleum systems were quantitatively assessed for undiscovered resources in the Western Canada Sedimentary Basin.

  19. Sedimentary geology of the middle Carboniferous of the Donbas region (Dniepr-Donets Basin, Ukraine).

    PubMed

    van Hinsbergen, Douwe J J; Abels, Hemmo A; Bosch, Wolter; Boekhout, Flora; Kitchka, Alexander; Hamers, Maartje; van der Meer, Douwe G; Geluk, Mark; Stephenson, Randell A

    2015-03-20

    The Paleozoic Dniepr-Donets Basin in Belarus, Ukraine, and Russia forms a major hydrocarbon province. Although well- and seismic data have established a 20 km thick stratigraphy, field-studies of its sediments are scarce. The inverted Donbas segment (Ukraine) exposes the middle Carboniferous part of the basin's stratigraphy. Here, we provide detailed sedimentological data from 13 sections that cover 1.5 of the total of 5 km of the Bashkirian and Moscovian stages and assess the paleoenvironment and paleo-current directions. Middle Carboniferous deposition occurred in a shelf environment, with coal deposition, subordinate fluvial facies, and abundant lower and middle shoreface facies, comprising an intercalated package of potential source and reservoir rocks. Sedimentary facies indicate a paleodepth range from below storm wave base to near-coastal swamp environments. Sedimentation and subsidence were hence in pace, with subtle facies changes likely representing relative sea-level changes. Paleocurrent directions are remarkably consistently southeastward in time and space in the different sedimentary facies across the Donbas Fold Belt, illustrating a dominant sedimentary infill along the basin axis, with little basin margin influence. This suggests that the middle Carboniferous stratigraphy of the Dniepr-Donets basin to the northwest probably contains significant amounts of fluvial sandstones, important for assessing hydrocarbon reservoir potential.

  20. Sedimentary geology of the middle Carboniferous of the Donbas region (Dniepr-Donets basin, Ukraine)

    PubMed Central

    van Hinsbergen, Douwe J. J.; Abels, Hemmo A.; Bosch, Wolter; Boekhout, Flora; Kitchka, Alexander; Hamers, Maartje; van der Meer, Douwe G.; Geluk, Mark; Stephenson, Randell A.

    2015-01-01

    The Paleozoic Dniepr-Donets Basin in Belarus, Ukraine, and Russia forms a major hydrocarbon province. Although well- and seismic data have established a 20 km thick stratigraphy, field-studies of its sediments are scarce. The inverted Donbas segment (Ukraine) exposes the middle Carboniferous part of the basin's stratigraphy. Here, we provide detailed sedimentological data from 13 sections that cover 1.5 of the total of 5 km of the Bashkirian and Moscovian stages and assess the paleoenvironment and paleo-current directions. Middle Carboniferous deposition occurred in a shelf environment, with coal deposition, subordinate fluvial facies, and abundant lower and middle shoreface facies, comprising an intercalated package of potential source and reservoir rocks. Sedimentary facies indicate a paleodepth range from below storm wave base to near-coastal swamp environments. Sedimentation and subsidence were hence in pace, with subtle facies changes likely representing relative sea-level changes. Paleocurrent directions are remarkably consistently southeastward in time and space in the different sedimentary facies across the Donbas Fold Belt, illustrating a dominant sedimentary infill along the basin axis, with little basin margin influence. This suggests that the middle Carboniferous stratigraphy of the Dniepr-Donets basin to the northwest probably contains significant amounts of fluvial sandstones, important for assessing hydrocarbon reservoir potential. PMID:25791400

  1. Sedimentary geology of the middle Carboniferous of the Donbas region (Dniepr-Donets basin, Ukraine)

    NASA Astrophysics Data System (ADS)

    van Hinsbergen, Douwe J. J.; Abels, Hemmo A.; Bosch, Wolter; Boekhout, Flora; Kitchka, Alexander; Hamers, Maartje; van der Meer, Douwe G.; Geluk, Mark; Stephenson, Randell A.

    2015-03-01

    The Paleozoic Dniepr-Donets Basin in Belarus, Ukraine, and Russia forms a major hydrocarbon province. Although well- and seismic data have established a 20 km thick stratigraphy, field-studies of its sediments are scarce. The inverted Donbas segment (Ukraine) exposes the middle Carboniferous part of the basin's stratigraphy. Here, we provide detailed sedimentological data from 13 sections that cover 1.5 of the total of 5 km of the Bashkirian and Moscovian stages and assess the paleoenvironment and paleo-current directions. Middle Carboniferous deposition occurred in a shelf environment, with coal deposition, subordinate fluvial facies, and abundant lower and middle shoreface facies, comprising an intercalated package of potential source and reservoir rocks. Sedimentary facies indicate a paleodepth range from below storm wave base to near-coastal swamp environments. Sedimentation and subsidence were hence in pace, with subtle facies changes likely representing relative sea-level changes. Paleocurrent directions are remarkably consistently southeastward in time and space in the different sedimentary facies across the Donbas Fold Belt, illustrating a dominant sedimentary infill along the basin axis, with little basin margin influence. This suggests that the middle Carboniferous stratigraphy of the Dniepr-Donets basin to the northwest probably contains significant amounts of fluvial sandstones, important for assessing hydrocarbon reservoir potential.

  2. Petroleum prospects for offshore sedimentary basins in the eastern Papua New Guinea and Solomon Islands regions

    SciTech Connect

    Bruns, T.R.; Vedder, J.G. )

    1990-06-01

    Intra-arc basins in the Buka-Bougainville region of Papua New Guinea and in the Solomon Islands contain thick sedimentary sequences that may be prospective for petroleum. The Queen Emma basin, between Bougainville and New Ireland, contains as much as 8 km of deformed Oligocene and younger strata. The Central Solomons Trough, which underlies New Georgia Sound, is a composite intra-arc basin that contains late Oligocene and younger strata as much as 7 km thick. Farther east, beneath Indispensable Strait, the down-faulted Indispensable basin locally contains as much as 5.4 km of Miocene( ) and younger strata, and the offshore part of Mbokokimbo basin off eastern Guadalcanal includes 6 km or more of late Miocene and younger strata. All of these basins have some of the attributes necessary to generate and trap petroleum. Structural and stratigraphic traps are common, including faulted anticlines, sedimentary wedges, and carbonate reefs and reef-derived deposits on submarine ridges and along the basin margins. The thickness of the basin deposits ensures that some strata are buried deeply enough to be within the thermal regime required for hydrocarbon generation. However, little source or reservoir rock information is available because of the lack of detailed surface and subsurface stratigraphy. Moreover, much of the basin sediment is likely to consist of volcaniclastic material, derived from uplifted volcanogenic rocks surrounding the basins, and may be poor in source and reservoir rocks. Until additional stratigraphic information is available, analysis of the petroleum potential of these basins is a matter of conjecture.

  3. Geometry of the San Andreas Fault and Sedimentary Basin in the Northern Salton Trough

    NASA Astrophysics Data System (ADS)

    Fuis, G. S.; Bauer, K.; Catchings, R.; Goldman, M.; Ryberg, T.; Scheirer, D. S.; Langenheim, V. E.; Rymer, M. J.; Persaud, P.; Stock, J. M.; Hole, J. A.

    2014-12-01

    The Salton Seismic Imaging Project (SSIP) was undertaken, in part, to provide more accurate information on the plate-boundary faults and basin geometry in the Salton Trough region. One of these faults, the southernmost San Andreas Fault (SAF) zone in the northern Salton Trough (Coachella Valley), is considered by many to be likely to produce a large-magnitude earthquake in the near future. We report here on the geometry of the SAF and the adjacent sedimentary basin beneath the Coachella Valley. We interpret two seismic profiles in the northern Salton Trough that are orthogonal to the axis of the Coachella Valley. Seismic imaging, potential-field studies, and (or) earthquake hypocentral relocations along these profiles indicate that the active strand of the SAF dips NE. On a southern profile, through the Mecca Hills, we obtain a reflection image of the SAF zone in the depth range of 6-12 km that coincides with the microearthquake pattern reported by Hauksson et al. (2012), dipping ~ 60° NE. Steeply dipping reflectors above 6 km emerge at the surface at mapped secondary fault traces in the Mecca Hills, clearly defining a "flower structure" for the upper SAF. On the second profile, from Palm Springs to Landers, two alternative interpretations of SAF structure are possible. By one interpretation, which is based on earthquakes alone, the Banning and Garnet Hill Faults are two closely spaced faults, dipping ~ 60° NNE that pass through two aftershock clusters of the 1986 M 5.9 North Palm Springs earthquake. By the second interpretation, which is based on our reflection imaging on this line, the Banning and Garnet Hills faults converge at 10-km depth; below that depth, a single SAF dips ~ 60° NNE. In the second interpretation, the faults above 10 km resemble the flower structure interpreted beneath the Mecca Hills on our southern profile. The deeper fault in the second interpretation is subparallel to the closely spaced faults of the first interpretation but a few km

  4. Sedimentary basin geochemistry and fluid/rock interactions workshop

    SciTech Connect

    1991-12-31

    Fundamental research related to organic geochemistry, fluid-rock interactions, and the processes by which fluids migrate through basins has long been a part of the U.S. Department of Energy Geosciences program. Objectives of this program were to emphasize those principles and processes which would be applicable to a wide range of problems associated with petroleum discovery, occurrence and extraction, waste disposal of all kinds, and environmental management. To gain a better understanding of the progress being made in understanding basinal fluids, their geochemistry and movement, and related research, and to enhance communication and interaction between principal investigators and DOE and other Federal program managers interested in this topic, this workshop was organized by the School of Geology and Geophysics and held in Norman, Oklahoma in November, 1991.

  5. Sedimentary environment of the La Rosa Formation, Maracaibo Basin

    SciTech Connect

    Rossi, D.; Noel, J.A.

    1993-02-01

    The La Rosa formation, Miocene consists of three facies: basal sand, the Santa Barbara, a middle shale, and the upper La Rosa Sand. The sands are variably productive. Paleontologic studies by others have shown the La Rosa Formation to be of marine origin. The shape of the SP curve of the Santa Barbara in bell shaped, caused by fining upward of the sand. This shape is typical with a beach deposit formed during transgression. The shale, because of its lithology and fossil content, represents shallow marine origin. The wine glass shape of the SP of the La Rosa sand is a beach sand, the result of a coarsening upward grain size during regression. An isopach of the La Rosa Formation and isoliths of the two sand units show a thickening trend from northeast to southwest. The thickest area trends diagonally across the center of the Basin. The study shows that the Miocene sea entered the basin from the northeast, transgressed southwesterly depositing the Santa Barbara sand on top of the unconformity as it went. The movement was constricted by the highlands on three sides of the basin. The shale was then deposited in the resulting shallow marine environment. As the highlands gradually rose, the sea regressed to the northeast depositing the La Rosa sand as it went.

  6. Earthquake ground motion prediction for real sedimentary basins: which numerical schemes are applicable?

    NASA Astrophysics Data System (ADS)

    Moczo, P.; Kristek, J.; Galis, M.; Pazak, P.

    2009-12-01

    Numerical prediction of earthquake ground motion in sedimentary basins and valleys often has to account for P-wave to S-wave speed ratios (Vp/Vs) as large as 5 and even larger, mainly in sediments below groundwater level. The ratio can attain values larger than 10 in unconsolidated sediments (e.g. in Ciudad de México). In a process of developing 3D optimally-accurate finite-difference schemes we encountered a serious problem with accuracy in media with large Vp/Vs ratio. This led us to investigate the very fundamental reasons for the inaccuracy. In order to identify the very basic inherent aspects of the numerical schemes responsible for their behavior with varying Vp/Vs ratio, we restricted to the most basic 2nd-order 2D numerical schemes on a uniform grid in a homogeneous medium. Although basic in the specified sense, the schemes comprise the decisive features for accuracy of wide class of numerical schemes. We investigated 6 numerical schemes: finite-difference_displacement_conventional grid (FD_D_CG) finite-element_Lobatto integration (FE_L) finite-element_Gauss integration (FE_G) finite-difference_displacement-stress_partly-staggered grid (FD_DS_PSG) finite-difference_displacement-stress_staggered grid (FD_DS_SG) finite-difference_velocity-stress_staggered grid (FD_VS_SG) We defined and calculated local errors of the schemes in amplitude and polarization. Because different schemes use different time steps, they need different numbers of time levels to calculate solution for a desired time window. Therefore, we normalized errors for a unit time. The normalization allowed for a direct comparison of errors of different schemes. Extensive numerical calculations for wide ranges of values of the Vp/Vs ratio, spatial sampling ratio, stability ratio, and entire range of directions of propagation with respect to the spatial grid led to interesting and surprising findings. Accuracy of FD_D_CG, FE_L and FE_G strongly depends on Vp/Vs ratio. The schemes are not

  7. BasinVis 1.0: A MATLAB®-based program for sedimentary basin subsidence analysis and visualization

    NASA Astrophysics Data System (ADS)

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

    2016-06-01

    Stratigraphic and structural mapping is important to understand the internal structure of sedimentary basins. Subsidence analysis provides significant insights for basin evolution. We designed a new software package to process and visualize stratigraphic setting and subsidence evolution of sedimentary basins from well data. BasinVis 1.0 is implemented in MATLAB®, a multi-paradigm numerical computing environment, and employs two numerical methods: interpolation and subsidence analysis. Five different interpolation methods (linear, natural, cubic spline, Kriging, and thin-plate spline) are provided in this program for surface modeling. The subsidence analysis consists of decompaction and backstripping techniques. BasinVis 1.0 incorporates five main processing steps; (1) setup (study area and stratigraphic units), (2) loading well data, (3) stratigraphic setting visualization, (4) subsidence parameter input, and (5) subsidence analysis and visualization. For in-depth analysis, our software provides cross-section and dip-slip fault backstripping tools. The graphical user interface guides users through the workflow and provides tools to analyze and export the results. Interpolation and subsidence results are cached to minimize redundant computations and improve the interactivity of the program. All 2D and 3D visualizations are created by using MATLAB plotting functions, which enables users to fine-tune the results using the full range of available plot options in MATLAB. We demonstrate all functions in a case study of Miocene sediment in the central Vienna Basin.

  8. Processing of thermal parameters for the assessment of geothermal potential of sedimentary basins

    NASA Astrophysics Data System (ADS)

    Pasquale, V.; Chiozzi, P.; Gola, G.; Verdoya, M.

    2009-04-01

    The growing interest on renewable energy sources is stimulating new efforts aimed at the assessment of geothermal potential in several countries, and new developments are expected in the near future. In this framework, a basic step forward is to focus geothermal investigations on geological environments which so far have been relatively neglected. Some intracontinental sedimentary basins could reveal important low enthalpy resources. The evaluation of the geothermal potential in such geological contexts involves the synergic use of geophysical and hydrogeological methodologies. In sedimentary basins a large amount of thermal and hydraulic data is generally available from petroleum wells. Unfortunately, borehole temperature data are often affected by a number of perturbations which make very difficult determination of the true geothermal gradient. In this paper we addressed the importance of the acquisition of thermal parameters (temperature, geothermal gradient, thermal properties of the rock) and the technical processing which is necessary to obtain reliable geothermal characterizations. In particular, techniques for corrections of bottom-hole temperature (BHT) data were reviewed. The objective was to create a working formula usable for computing the undisturbed formation temperature for specific sedimentary basins. As test areas, we analysed the sedimentary basins of northern Italy. Two classical techniques for processing temperature data from oil wells are customarily used: (i) the method by Horner, that requires two or more measurements of bottom-hole temperatures carried out at the same depth but at different shut-in times te and (ii) the technique by Cooper and Jones, in which several physical parameters of the mud and formation need to be known. We applied both methods to data from a number of petroleum explorative wells located in two areas of the Po Plain (Apenninic buried arc and South Piedmont Basin - Pedealpine homocline). From a set of about 40 wells

  9. Modern sedimentary environments in a large tidal estuary, Delaware Bay

    USGS Publications Warehouse

    Knebel, H. J.

    1989-01-01

    Data from an extensive grid of sidescan-sonar records reveal the distribution of sedimentary environments in the large, tidally dominated Delaware Bay estuary. Bathymetric features of the estuary include large tidal channels under the relatively deep (> 10 m water depth) central part of the bay, linear sand shoals (2-8 m relief) that parallel the sides of the tidal channels, and broad, low-relief plains that form the shallow bay margins. The two sedimentary environments that were identified are characterized by either (1) bedload transport and/or erosion or (2) sediment reworking and/or deposition. Sand waves and sand ribbons, composed of medium to coarse sands, define sites of active bedload transport within the tidal channels and in gaps between the linear shoals. The sand waves have spacings that vary from 1 to 70 m, amplitudes of 2 m or less, and crestlines that are usually straight. The orientations of the sand waves and ribbons indicate that bottom sediment movement may be toward either the northwest or southeast along the trends of the tidal channels, although sand-wave asymmetry indicates that the net bottom transport is directed northwestward toward the head of the bay. Gravelly, coarse-grained sediments, which appear as strongly reflective patterns on the sonographs, are also present along the axes and flanks of the tidal channels. These coarse sediments are lag deposits that have developed primarily where older strata were eroded at the bay floor. Conversely, fine sands that compose the linear shoals and muddy sands that cover the shallow bay margins appear mainly on the sonographs either as smooth featureless beds that have uniform light to moderate shading or as mosaics of light and dark patches produced by variations in grain size. These acoustic and textural characteristics are the result of sediment deposition and reworking. Data from this study (1) support the hypothesis that bed configurations under deep tidal flows are functions of current

  10. Sedimentary response to subsidence history of Illinois basin

    SciTech Connect

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

    1986-05-01

    The Illinois basin formed through initial isostatic subsidence and subsequent thermal subsidence in response to mantle intrusion that formed a three-arm rift 535-555 Ma. Tectonic subsidence curves calculated from three wells show that, when extended across the Sauk-Tippecanoe, Ordovician-Silurian, and Tippecanoe-Kaskaskia unconformities, they fit a post-rift thermal contraction model. These unconformities formed because, as suggested by some investigators for other areas, the rate of eustatic sea level fall exceeded the rate of thermal basement subsidence. Residual tectonic subsidence curves were calculated by subtracting post-rift thermal contraction curves from calculated tectonic subsidence curves. These residual curves indicate misassigned depositional times, periods of non-equilibrium sedimentation and subsidence, and the start of new subsidence episodes. Middle to Late Ordovician negative residual curves were corrected to null values by revising depositional times. Accordingly, the duration of the Blackriveran expands to 17 m.y., and the Trentonian through middle Maysvillian contracts to 2.5 m.y. Silurian and Late Devonian through Early Mississippian positive residual curves correspond to formation and filling of 300-m-deep, sediment-starved basins. A strong negative residual curve, beginning in the middle Mississippian, corresponds to a second tectonic subsidence event.

  11. Tectonic control of the sedimentary record: Constraints from quantitative basin modeling

    SciTech Connect

    Cloetingh, S.A.P.L.; Van Balen, R.T.; Zoetemeijer, B.P. )

    1993-09-01

    The incorporation of finite strength of the lithosphere during rifting in models for extensional basin formation in conjunction with temporal changes in tectonic stress levels leads to the prediction of rapid vertical motions in these basins with a rate and magnitude comparable to second- and third-order changes in relative sea level. We present results of modeling simulations, incorporating the interplay of flank uplift and erosion for rifted basins in the northern Atlantic/North Sea area. The incorporation of the mechanical properties of the lithosphere in forward stratigraphic modeling appears also to be of key importance for an accurate prediction of the record of vertical motions in foreland fold and thrust belts. Models invoking the mechanical coupling between plate flexure and near-surface brittle tectonics are capable of producing onlap/offlap patterns in syntectonic basins sometimes strikingly similar to the basin-fill signatures attributed to third-order glacio-eustatic signals. The full incorporation of structural geological constraints in forward modeling of basin stratigraphy proves to be a powerful instrument in linking different temporal and spatial scales in the sedimentary record. This approach also leads to a quantification of the tectonic control of the sedimentary record in frequency bands hitherto primarily attributed to external forcing functions.

  12. Carbon and Nitrogen Stable Isotopes of Sedimentary Organic Matter From the Santa Monica Basin

    NASA Astrophysics Data System (ADS)

    Luo, J. Y.; Erohina, T.; Paytan, A.

    2005-12-01

    The California Continental Borderland is a tectonically active area, characterized by 23 basins located at different distances from sources of terrigenous sediment, local intermittent rivers and coastal upwelling zones and thus displaying different sedimentation sources and processes. The Santa Monica Basin (938m depth), a Southern California Inner Borderland basin, is a closed basin and fed by the Santa Barbara littoral cell. During sea level lowstands, the littoral cell is inactive and the canyon was fed directly by the Santa Clara River, which is presently not dammed and is known to be capable of generating hyperpycnal flows during ENSO related floods. Ocean Drilling Program (ODP) Site 1015 was drilled in the basin plain area and penetrated through a 150-meter late Quaternary sedimentary section. The sediments recovered at Site 1015 are grouped into a single lithostratigraphic unit consisting of three alternating sedimentary units: medium- to fine-grained sand, silty clay, and nanofossil clay. Samples of the drill core from the top 60 meters of sediment was obtained and analyzed at ~50cm intervals to obtain a high-resolution record of organic matter distribution and isotope record within the different intervals. The δ13C values of total organic carbon (TOC) and δ15N values, as well as the C/N ratio were obtained and used to differentiate between marine and terrestrial sediment inputs to the basin. Additionally, the TOC data may indicate if highstand and lowstand deposits show significant compositional differences.

  13. 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.

  14. Report of the Workshop on Geologic Applications of Remote Sensing to the Study of Sedimentary Basins

    NASA Technical Reports Server (NTRS)

    Lang, H. R. (Editor)

    1985-01-01

    The Workshop on Geologic Applications of Remote Sensing to the Study of Sedimentary Basins, held January 10 to 11, 1985 in Lakewood, Colorado, involved 43 geologists from industry, government, and academia. Disciplines represented ranged from vertebrate paleontology to geophysical modeling of continents. Deliberations focused on geologic problems related to the formation, stratigraphy, structure, and evolution of foreland basins in general, and to the Wind River/Bighorn Basin area of Wyoming in particular. Geological problems in the Wind River/Bighorn basin area that should be studied using state-of-the-art remote sensing methods were identified. These include: (1) establishing the stratigraphic sequence and mapping, correlating, and analyzing lithofacies of basin-filling strata in order to refine the chronology of basin sedimentation, and (2) mapping volcanic units, fracture patterns in basement rocks, and Tertiary-Holocene landforms in searches for surface manifestations of concealed structures in order to refine models of basin tectonics. Conventional geologic, topographic, geophysical, and borehole data should be utilized in these studies. Remote sensing methods developed in the Wind River/Bighorn Basin area should be applied in other basins.

  15. Palynostratigraphy of the Erkovtsy field of brown coal (the Zeya-Bureya sedimentary basin)

    SciTech Connect

    Kezina, T.V.; Litvinenko, N.D.

    2007-08-15

    The Erkovtsy brown coal field in the northwestern Zeya-Bureya sedimentary basin (129-130{sup o}E, 46-47{sup o}N) is structurally confined to southern flank of the Mesozoic-Cenozoic Belogor'e depression. The verified stratigraphic scheme of the coalfield sedimentary sequence is substantiated by palynological data on core samples from 18 boreholes sampled in the course of detailed prospecting and by paleobotanical analysis of sections in the Yuzhnyi sector of the coalfield (data of 1998 by M.A. Akhmetiev and S.P. Manchester). Sections of the Erkovtsy, Arkhara-Boguchan, and Raichikha brown-coal mines are correlated. Stratigraphic subdivisions distinguished in the studied sedimentary succession are the middle and upper Tsagayan subformations (the latter incorporating the Kivda Beds), Raichikha, Mukhino, Buzuli, and Sazanka formations.

  16. Sedimentary and structural controls on seismogenic slumping within mass transport deposits from the Dead Sea Basin

    NASA Astrophysics Data System (ADS)

    Alsop, G. I.; Marco, S.; Weinberger, R.; Levi, T.

    2016-10-01

    Comparatively little work has been undertaken on how sedimentary environments and facies changes can influence detailed structural development in slump sheets associated with mass transport deposits (MTDs). The nature of downslope deformation at the leading edge of MTDs is currently debated in terms of frontally emergent, frontally confined and open-toed models. An opportunity to study and address these issues occurs within the Dead Sea Basin, where six individual slump sheets (S1-S6) form MTDs in the Late Pleistocene Lisan Formation. All six slumps, which are separated from one another by undeformed beds, are traced towards the NE for up to 1 km, and each shows a change in sedimentary facies from detrital-rich in the SW, to more aragonite-rich in the NE. The detrital-rich facies is sourced predominantly from the rift margin 1.5 km further SW, while the aragonite-rich facies represents evaporitic precipitation in the hyper saline Lake Lisan. The stacked system of MTDs translates downslope towards the NE and follows a pre-determined sequence controlled by the sedimentary facies. Each individual slump roots downwards into underlying detrital-rich layers and displays a greater detrital content towards the SW, which is marked by increasing folding, while increasing aragonite content towards the NE is associated with more discrete thrusts. The MTDs thin downslope towards the NE, until they pass laterally into undeformed beds at the toe. The amount of contraction also reduces downslope from a maximum of 50% to < 10% at the toe, where upright folds form diffuse 'open-toed' systems. We suggest that MTDs are triggered by seismic events, facilitated by detrital-rich horizons, and controlled by palaeoslope orientation. The frequency of individual failures is partially controlled by local environmental influences linked to detrital input and should therefore be used with some caution in more general palaeoseismic studies. We demonstrate that MTDs display 'open toes' where

  17. Deep seismic reflection profiling of sedimentary basins offshore Brazil: Geological objectives and preliminary results in the Sergipe Basin

    NASA Astrophysics Data System (ADS)

    Mohriak, Webster Ueipass; Lira Rabelo, JoséHenrique; De Matos, Renato Darros; De Barros, Mozart C.

    1995-12-01

    The first deep seismic reflection profiles offshore Brazil were acquired in Campos Basin and processed to 10 s TWT in 1984. Starting in 1989, Petrobrás acquired an extensive data set of deep seismic profiles using special acquisition equipment capable of effectively penetrating through the sedimentary layers and imaging the whole crustal architecture. These deep (18 s TWT) seismic reflection profiles extend across the Atlantic-type marginal basins, from the platform to the deepwater province, presently considered frontier regions for petroleum exploration. This work addresses the geological objectives of a deep seismic profile in the Sergipe Basin and discusses the results obtained by integrating regional seismic, gravity and magnetic data. When combined, these data provide evidence that deep seismic reflectors observed in the Sergipe Basin are related to intracrustal-upper mantle structures rather than sedimentary features. The deep seismic reflection profile in the Sergipe Basin also suggests that, rather than a non-volcanic passive margin, the deepwater extension of this basin is marked by several magmatic structures, including thick wedges of seaward-dipping reflectors and volcanic plugs. These magmatic features are associated with basinforming processes resulting from lithospheric extension during the breakup of Gondwana in the Early Cretaceous and subsequent emplacement of oceanic crust. These results are compared to the crustal scale structures observed in the Campos Basin, in the southeastern margin of Brazil. The interpretation of the deep structure of these basins indicates that final separation between the South American and African plates formed passive margins characterized by different patterns of crustal attenuation underlying the rift blocks.

  18. Estimation of Potential Carbon Dioxide Storage Capacities of Onshore Sedimentary Basins in Republic of Korea

    NASA Astrophysics Data System (ADS)

    Park, S.; Kim, J.; Lee, Y.

    2010-12-01

    The potential carbon dioxide storage capacities of the five main onshore sedimentary basins (Chungnam, Gyeongsang, Honam, Mungyeong, and Taebaeksan Basins) in Republic of Korea are estimated based on the methods suggested by the United States National Energy Technology Laboratory (NETL). The target geologic formations considered for geologic storage of carbon dioxide in the sedimentary basins are sandstone and coal beds. The density of carbon dioxide is set equal to 446.4 kg/m3. The adsorption capacity and density of coal (anthracite) are set equal to 2.71 × 10-2 kg/kg and 1.82 × 103 kg/m3, respectively. The average storage efficiency factors for sandstone and coal are set equal to 2.5% and 34.0%, respectively. The Chungnam Basin has the sandstone volume of 72 km3 and the coal volume of 1.24 km3. The average porosity of sandstone in the Chungnam Basin is 3.8%. As a result, the potential carbon dioxide storage capacities of sandstone and coal in the Chungnam Basin are estimated to be 31 Mton and 21 Mton, respectively. The Gyeongsang Basin has the sandstone volume of 1,960 km3. The average porosity of sandstone in the Gyeongsang Basin is 4.6%. As a result, the potential carbon dioxide storage capacity of sandstone in the Gyeongsang Basin is estimated to be 1,011 Mton. The Honam Basin has the sandstone volume of 8 km3 and the coal volume of 0.27 km3. The average porosity of sandstone in the Honam Basin is 1.9%. As a result, the potential carbon dioxide storage capacities of sandstone and coal in the Honam Basin are estimated to be 2 Mton and 5 Mton, respectively. The Mungyeong Basin has the sandstone volume of 60 km3 and the coal volume of 0.66 km3. The average porosity of sandstone in the Mungyeong Basin is 2.0%. As a result, the potential carbon dioxide storage capacities of sandstone and coal in the Mungyeong Basin are estimated to be 13 Mton and 11 Mton, respectively. The Taebaeksan Basin has the sandstone volume of 71 km3 and the coal volume of 0.73 km3. The

  19. Short and long term sediment flux in an inner-alpine sedimentary basin (Hohe Tauern, Austria)

    NASA Astrophysics Data System (ADS)

    Götz, Joachim; Schrott, Lothar

    2015-04-01

    Combined analyses of short and long term sediment fluxes in mountain environments have been rarely carried out until now. However, the relation of integrated postglacial landform volumes to single events (e.g. debris flows) provide the opportunity to establish meaningful frequency-magnitude-relationships, to evaluate present day geomorphic activity more reasonable, and to complement time series data typically covering only a short period of time. In this study we investigate recent and postglacial sediment flux in a small-scale denudation-accumulation system in the Hohe Tauern Range (Austrian Alps) using a complementary multi method approach including surface, subsurface and temporal analyses. We reconstructed the infill history and sedimentary architecture of the almost closed Gradenmoos basin, which has been filled up with sediments from different source areas delivered by mainly debris flows, rockfall and avalanche activity, and fluvial processes. In former times, glacial, glacio-fluvial and lacustrine sedimentation contributed to the basin fill as well. This process diversity led to a variety of interfingering and nested sediment storage landforms with a complex postglacial stratigraphy. Most important landforms include floodplain and peat bog deposits in the basin center as well as debris cones and talus sheets adjacent to the surrounding rockwalls. Postglacial basin sedimentation started after Younger Dryas deglaciation as indicated by radiocarbon ages of early-Holocene sediment core samples taken in the basin. For the following 7500 years, trap efficiency was maximised due to the presence of a former lake which is proved by morphometric, palynologic and stratigraphic data. Peat bog development finally began around 3500 years ago in the distal part of the basin. We interpolated the bedrock interface below the basin fill deposits using bedrock coordinates derived from core-drilling, geophysical prospection (electrical resistivity tomography, refraction seismic

  20. Sedimentary Basins: A Deeper Look at Seattle and Portland's Earthquake Hazards

    NASA Astrophysics Data System (ADS)

    Thompson, M.; Frankel, A. D.; Wirth, E. A.; Vidale, J. E.; Han, J.

    2015-12-01

    Seattle, Washington and Portland, Oregon, two major metropolitan areas in the Pacific Northwest, are vulnerable to earthquakes on active local faults, deep intraslab earthquakes, and megathrust earthquakes on the Cascadia Subduction Zone (CSZ). Both cities are located within sedimentary basins that could increase this hazard. The Seattle basin is ~8 km in depth and is located beneath downtown Seattle. The 6-km-deep Tualatin basin (McPhee et al., 2014) sits below and west of downtown Portland with the shallow Portland basin to the northeast. Unlike other West Coast sedimentary basins, the Tualatin contains a higher-velocity Columbia River basalt layer between sediment layers. The velocity contrast between stiff bedrock surrounding the basins and soft sediment within can cause seismic waves to amplify greatly, increasing shaking intensity and duration at the surface. For example, our observations show amplification of seismic waves by factors of 2 - 4 within the Seattle basin. Basin geometry can also increase local shaking by converting incident S-waves to surface waves, and focusing S-waves at basin edges. We characterize effects of the Seattle, Tualatin and Portland basins by modeling with 3-D numerical methods. To evaluate these effects, we use data from the 2001 M6.8 Nisqually, the 2009 M4.5 Kingston, and the 2006 M3.8 Vancouver earthquakes recorded by stations operated by the US Geological Survey (10 - 25 stations) and the Pacific Northwest Seismic Network (7 - 81 stations). Time differences between S-waves and S-converted-to-P-waves at basin/bedrock interfaces as well as reverberations from teleseisms (global earthquakes) are used to constrain the basin depth and structure of the three basins. Basin effects are modeled using a 3D finite difference program to generate synthetic seismograms. Results will be used to improve the Seattle and Portland 3D velocity models and to better understand and predict amplification of strong motion. We also plan similar analyses

  1. Overpressure Evolution during Sedimentary Basin Diagenesis: Implications for Hydrocarbon Transport By Solitary Waves

    NASA Astrophysics Data System (ADS)

    Joshi, A.; Appold, M. S.

    2014-12-01

    Recent research has shown solitary waves to be capable of transporting fluids through porous media at rates orders of magnitude faster than predicted from Darcy's law. Solitary waves are expressed as regions of high fluid pressure and porosity. The waves form and propagate where permeability is a sensitive function of effective stress, fluid pressure approaches lithostatic pressure, and the rate of fluid pressure generation is rapid compared to the rate of fluid pressure diffusion. The purpose of the present study was to investigate the pressure generation rates that can develop in a sedimentary basin over a range of possible geologic conditions so that the potential for solitary wave formation can be assessed. Pressure generation rates were calculated for a generic sedimentary basin by constructing a two-dimensional numerical model that treated sediment deposition, compaction, heat flow, kerogen maturation, hydrocarbon formation, and the flow of water, oil, and gas. The results showed compaction disequilibrium and hydrocarbon formation to be the two principal causes of pressure generation, respectively. Pressure generation rates for typical sedimentary basinal conditions were found to be on the order of 1's of Pa/year, up to a maximum of ~400 Pa/year under the most favorable pressure generating conditions. These pressure generation rates would be sufficient to form oil-saturated solitary waves but too low to form methane-saturated solitary waves because of the higher rate of methane pressure diffusion compared to oil, due to methane's lower viscosity. To form methane-saturated solitary waves, pressure generation rates of at least ~1800 Pa/year are needed, which are unlikely to be produced by sedimentary basin diagenetic processes, but could possibly be produced by earthquakes.

  2. Early Tertiary subsidence and sedimentary facies - northern Sirte Basin, Libya

    SciTech Connect

    Gumati, Y.D.; Kanes, W.H.

    1985-01-01

    The subsidence curves and subsidence rate curves for the Sirte basin, constructed from the stratigraphic record, show that subsidence was continuous throughout Late Cretaceous and Tertiary times, reaching a maximum during the Paleocene and Eocene, when a major reactivation of faults occurred. Shales and carbonates were deposited during all of the Late Cretaceous and Tertiary. Abrupt lateral facies changes occur from the platform areas toward the deeper troughs along with steep downdip thickening. These conditions were probably assisted by contemporaneous faulting along structurally weak hinge lines where the dominant structural elements are normal step faults. The absence of upper Paleozoic and lower Mesozoic sediments suggests that the area was domed, faulted, and eroded during the late Mesozoic. As a result of crustal extension during the Paleocene, a marked lithologic and structural change occurred. The Heira Shale succeeded the Kalash Limestone in the Marada trough. Reactivation of the earlier faults, accompanied by an increase in the sediment supply from the south, caused these lower Paleocene shales to cover the entire area, with the exception of the old highs where carbonate deposition continued. An intercalation of shales and carbonates provides a sensitive indicator of change of depth and sediment type.

  3. Early Tertiary subsidence and sedimentary facies - Northern Sirte Basin, Libya

    SciTech Connect

    Gumati, Y.D.; Kanes, W.H.

    1985-12-01

    The subsidence curves and subsidence rate curves for the Sirte basin, constructed from the stratigraphic record, show that subsidence was continuous throughout Late Cretaceous and Tertiary times, reaching a maximum during the Paleocene and Eocene, when a major reactivation of faults occurred. Shales and carbonates were deposited during all of the Late Cretaceous and Tertiary. Abrupt lateral facies changes occur from the platform areas toward the deeper troughs along with steep downdip thickening. The absence of upper Paleozoic and lower Mesozoic sediments suggests that the area was domed, faulted, and eroded during the late Mesozoic. As a result of crustal extension during the Paleocene, a marked lithologic and structural change occurred. The Heira Shale succeeded the Kalash Limestone in the Marada trough. Reactivation of the earlier faults, accompanied by an increase in the sediment supply from the south, caused these lower Paleocene shales to cover the entire area, with the exception of the old highs where carbonate deposition continued. An intercalation of shales and carbonates provides a sensitive indicator of change of depth and sediment type. 14 figures.

  4. Miocene-Pliocene transition in the southern Cyprus basins: The sedimentary expression of regional tectonic events

    SciTech Connect

    Orzag-Sperber, F.; Rouchy, J.M. )

    1988-08-01

    In the southern part of Cyprus, a Maastrichtian-Pleistocene sedimentary area fringes Troodos Mountain, a fragment of an ancient crust. During the Neogene, three basins formed in this area: Polemi, Pissouri, and Psematismenos. A deep marine condition has prevailed since the Maastrichtian. During the Paleocene and early Miocene, the sea gradually become shallower until the Messinian, where the most spectacular sedimentary event concerns the deposition of evaporites contemporaneous with other Mediterranean evaporites. Some sedimentary phenomena express the tectonic instability during the upper Miocene. A well-known tectonic event affecting the east Mediterranean region generally referred to as the Miocene-Pliocene phase occurs at the Miocene-Pliocene limit. Recent sedimentological studies indicate this event is in fact complex. The Tortonian-lower Pliocene period is marked by a constraint involving an N20 distension in the Polemi and Pissouri basins and an N100 distension in the Psematismenos basin. Sedimentologic studies have demonstrated three tectonic pulsations during the Messinian prior to the Pliocene transgression. These are expressed by two episodes of seismic brecciation and a paleoemersion indicated by paleosols and detrital discharges. These phenomena suggest brief tectonic instability during the Messinian. Microtectonic studies reveal that the main change in tectonic constraint does not coincide with the Miocene-Pliocene contact but occurs at the top of the lower Pliocene.

  5. Amplification and Attenuation in the Los Angeles and Kanto Sedimentary Basins using the Ambient Seismic Field

    NASA Astrophysics Data System (ADS)

    Denolle, M.; Prieto, G.; Lawrence, J. F.; Beroza, G. C.; Hirata, N.; Nakagawa, S.; Miyake, H.; Kasahara, K.; Sakai, S.; Aketagawa, T.; Kimura, H.

    2010-12-01

    Ground motion prediction is traditionally estimated in seismic hazard analysis using parametric scaling relations, which are often referred to as "attenuation relations." Increasingly, seismologists are turning to simulation-based hazard analysis. There are at least two reasons for this. First, it allows seismologists to overcome the scarcity of data from large events in the data. Second, it exploits our growing knowledge of the geological complexity of the Earth's crust and our ability to model wave propagation through it. The accuracy of these simulations is critical to their use for risk reduction, but is limited by our incomplete knowledge of the elastic and anelastic structure of the subsurface. The situation is particularly acute for sedimentary basins that underlie densely populated urban centers such as Los Angeles and Tokyo, both because the exposure is so high, and because it is difficult to obtain new images of Earth structure in urban settings. In this study, we show how ambient seismic field analysis can improve this situation. We take the advantage of the dense seismic networks in those areas and use 9 months of continuous records for about 180 stations from the Southern Californian Seismic Networks for Los Angeles and 6 months of a combination of 190 MeSO-net stations and 110 Hi-net instruments in Tokyo area. We estimate the basin amplification of these comparable urban centers with ambient field transfer function, or impulse response. The ambient seismic field also provides constraints on the attenuation signal in surface waves, and hence on the anelastic structure of the Earth. We exploit this by using the real part of the complex coherence to estimate the attenuation coefficient of Rayleigh waves, and from it variations in the anelastic structure. We acknowledge the support by the Special Project for Earthquake Disaster Mitigation in Tokyo Metropolitan Area from the Ministry of Education, Culture, Sports, Science and Technology of Japan.

  6. Seismic valve as the main mechanism for sedimentary fluid entrapment within extensional basin: example of the Lodève Permian Basin (Hérault, South of France).

    NASA Astrophysics Data System (ADS)

    Laurent, D.; Lopez, M.; Chauvet, A.; Imbert, P.; Sauvage, A. C.; Martine, B.; Thomas, M.

    2014-12-01

    During syn-sedimentary burial in basin, interstitial fluids initially trapped within the sedimentary pile are easily moving under overpressure gradient. Indeed, they have a significant role on deformation during basin evolution, particularly on fault reactivation. The Lodève Permian Basin (Hérault, France) is an exhumed half graben with exceptional outcrop conditions providing access to barite-sulfides mineralized systems and hydrocarbon trapped into rollover faults of the basin. Architectural studies shows a cyclic infilling of fault zone and associated S0-parallel veins according to three main fluid events during dextral/normal faulting. Contrasting fluid entrapment conditions are deduced from textural analysis, fluid inclusion microthermometry and sulfide isotope geothermometer: (i) the first stage is characterized by an implosion breccia cemented by silicifications and barite during abrupt pressure drop within fault zone; (ii) the second stage consists in succession of barite ribbons precipitated under overpressure fluctuations, derived from fault-valve action, with reactivation planes formed by sulphide-rich micro-shearing structures showing normal movement; and (iii) the third stage is associated to the formation of dextral strike-slip pull-apart infilling by large barite crystals and contemporary hydrocarbons under suprahydrostatic pressure values. Microthermometry, sulfide and strontium isotopic compositions of the barite-sulfides veins indicate that all stages were formed by mixing between deep basinal fluids at 230°C, derived from cinerite dewatering, and formation water from overlying sedimentary cover channelized trough fault planes. We conclude to a polyphase history of fluid trapping during Permian synrift formation of the basin: (i) a first event, associated with the dextral strike-slip motion on faults, leads to a first sealing of the fault zone; (ii) periodic reactivations of fault planes and bedding-controlled shearing form the main mineralized

  7. Structure and hydrocarbon potential of sedimentary basins of the far east marginal seas

    SciTech Connect

    Gnibidenko, H. ); Kononov, V. )

    1990-05-01

    Crustal structural of the Bering, Okhotsk Japan, East China, and South China marginal seas consists of continental plates and deep sea basins that are the elements of the lowermost order in the structure of transition zone from the Asia continent to the Pacific Ocean. Two stages are recognized in the crustal evolution of the northwest Pacific transition zone: (1) geosyncline development that began in the pre-Paleozoic and continues to the present within island arcs; and (2) quasiplatform stage that began in the late Cretaceous and continues to the Holocene within shelf plates. The continental margins of the Far East seas consist of Cenozoic terrigenous cover and pre-Cenozoic basement composed of geosyncline rock association. Normal faults control graben features in the basement and develop rift systems. Paleogene subcontinental formations make up the lowermost section of the cover. A major Oligocene-Holocene sequence (marine formations) overlies and smooths rough topography of the basement and creates giant sedimentary basins. Sediment thickness of the basins attains 10 km. Tectonic evolution of the marginal seas implies the shelf plates to be young platforms and deep-sea basins are believed to be parts of the Pacific thalassocraton fenced by island arcs. The tectonic criterion enables us to differ and grade the provinces according to a hydrocarbon potential. Nearly 100 promising sedimentary basins are presently known in the Bering, Okhotst Japan, East China, and South China seas. About ten basins have been identified as hydrocarbon resources. Deep-sea basins also look promising for hydrocarbons. All the economically significant hydrocarbon accumulations in the Far East marginal seas are attributed to the Cenozoic sediment cover. Major resources are concentrated in the Miocene and Pliocene terrigenous sequences composed of progradation facies within the shelf plates.

  8. Sedimentary basins on the connugate margins of South America and Africa

    SciTech Connect

    Moore, G.T. )

    1990-05-01

    An Early Cretaceous spreading system formed the South Atlantic by separating South America from Africa along two subparallel major transform fault systems. The distribution of major sedimentary depocenters is controlled by the complex interplay of two factors: the late Mesozoic-Cenozoic cycle of sea-floor spreading and the legacy of a Precambrian collage of ancient cores that comprised western Gondwana. Three spreading modes created this configuration: rift, transform, and subduction. Each produces a different geometry and tectonic framework for the accumulation of sediment. Rifted margins (60%) contain basins that are elongate, form with their depocenter axes inboard of the ocean-continent transition, and rest on a tectonically complex, foundered basement. Transform margins have abrupt ocean-continent transitions. Such margins (30%) may be sediment starved or contain a thick sedimentary section controlled by the volcanic ridges of transform faults. Off Tierra del Fuego, Burdwood Bank is bounded on the north by a fossil (aseismic) subduction zone. The associated basin is an elongate, deformed accretionary prism of sediments on a gently dipping, faulted oceanic plate. The South Atlantic margins are divisible into 68 basins or segments that collectively contain over 33 {times} 106 km{sup 3} of syn- and postbreakup sediments. The South American margin contains 22 {times} 10{sup 6} km{sup 3} in 46 basins, and the African margin, 11 {times} 10{sup 6} km{sup 3} in 22 basins. Over 65% of the basins have a sediment column greater than 5 km with some depocenters that locally exceed 10 km. The source rock quality and character vary along both margins. The top of the oil generation window averages about 3.3 km; however, due to differing thermal histories, individual basins can depart significantly from this average.

  9. Alteration mineralogy and geochemistry as an exploration tool for detecting basement heat sources in sedimentary basins

    NASA Astrophysics Data System (ADS)

    Uysal, Tonguc; Gasparon, Massimo; van Zyl, Jacobus; Wyborn, Doone

    2010-05-01

    The Cooper Basin located in South Australia and Queensland hosts some of the hottest granites in the world at economic drilling depths (240°C at 3.5 km). Investigating the mechanism of heat-producing element enrichment in the Cooper Basin granite is crucial for understanding hot-dry rock geothermal systems and developing exploration strategies. Trace element (by ICP-MS) and stable isotope geochemistry of whole rock granite samples and hydrothermal phyllosilicate alteration minerals separated from the granite and overlying sandstones and mudstones of the Cooper Basin were examined in detail. Granite core samples from relatively shallow depths in Moomba 1 and Big Lake 1 are strongly altered with pervasive sericite (illite) and quartz precipitation, probably associated with intense micro-fracturing and veining. The intensity of hydrothermal alteration is less in deeper samples from Mcleod 1, Jolokia and Habanero 1. Highly altered granites from former holes are substantially enriched in lithophile elements, particularly in Cs, Rb, Be, Th, U and rare earth elements (REE) relative to the upper continental crust (UCC). U and Th contents with concentrations of up to 30 and 144 ppm, respectively, are 10 and 13 times higher than those of the UCC. Comparison of the trace element composition of the same samples dissolved by open beaker acid digestion and high-pressure acid bomb digestion (to dissolve zircon) shows that zircon is not the main repository of U and Th in the Cooper Basin granite. Instead, we propose that the enrichment of heat-producing elements was promoted by a regional hydrothermal event leading to the precipitation of U and Th- bearing minerals such as illite, K-feldspar and thorite. Crystallinity index (illite crystallinity) of the sericite indicates hydrothermal temperatures ranging from 250°C (in Moomba 1 and Big Lake 1) to 350°C (in McLeod 1 and Jolokia 1). In the overlying sedimentary rocks, crystallinity of authigenic illites translates to lower

  10. Sedimentary successions and the onset of the Neoproterozoic Jiangnan sub-basin in the Nanhua rift, South China

    NASA Astrophysics Data System (ADS)

    Wang, Jian; Zhou, Xiaolin; Deng, Qi; Fu, Xiugen; Duan, Taizhong; Guo, Xiumei

    2015-04-01

    Recent results of research from a regional geological survey have demonstrated that the Neoproterozoic Nanhuan strata in the Jiangnan sub-basin in the Nanhua rift in South China are built up of "wedge-shaped strata", which rest transgressively on the metamorphic basement. These strata are grouped, as indicated by our sedimentary facies analysis, into the following four depositional successions (with ten related sedimentary facies associations): (1) continental volcanic depositional succession; (2) continental siliciclastic depositional succession; (3) marine siliciclastic depositional succession; and (4) glacial depositional succession. Compared with the Hunan-Guangxi sub-basin and the Northern Zhejiang sub-basin, the sedimentary processes in the Jiangnan sub-basin are dominated by continental rather than marine facies. However, similar sedimentary successions with identical facies trends can be recognized in all these sub-basins. All the Neoproterozoic basin fills in South China are characterized by a deepening water trend leading from continental to fully marine facies, recording the evolution of a typical rift basin related to the break-up of Rodinia. The crystalline zircons from a rhyolite sample taken from the base part of the first succession in the Jiangnan sub-basin give a mean SHRIMP U-Pb age of 803 ± 9 Ma. The occurrence of the ca. 803 Ma volcanic rocks and the volcaniclastic rocks marks the onset of a new phase of depositional cycles in the Jiangnan sub-basin.

  11. Sedimentary evolution of the Paleozoic basin fill, southeast Turkey

    SciTech Connect

    Tunbridge, I.P. )

    1988-08-01

    The Paleozoic succession of southeast Turkey reaches its thickest development in the Hakkari district. Here, well-exposed Paleozoic rocks of Cambrian to Permian age are more than 5 km thick, representing a punctuated accumulation of clastic and carbonate sediments on the northern margin of the Arabian shield. Lower Cambrian rocks (< 1.5 km thick) are recorded in the Sadan Formation. A range of deltaic and fluviatile facies are present here. These developed as large-scale meandering then later braided river systems, which flowed north from the Arabian shield. Peritidal dolomites of the Koruk Formation follow, succeeded by 1 km of Cambrian-Ordovician storm-swept shelf sandstones and mudstones of the Seyisehir Formation. Following a Middle Ordovician break, a thin (25 m) Ashgillian siliciclastic shelf sea succession occurs, known as the Sort Tepe Formation. Silurian sediments are not found, and the Devonian of the Hakkari district is marked by the Upper Devonian Yiginli Formation. This formation records a 380-m regressive-transgressive fluvial-deltaic couplet, with deltaic conditions terminated by an Early Carboniferous eustatic sea-level rise. This event permitted the development of a 250 m-thick black shale facies (Koprulu Formation), which was succeeded by 130 m of carbonate mound facies (Belek Formation). Thick (2,000 m) carbonate sequences of the Habbur Formation (Permian) mark the start of the thick carbonate sequences which persisted from the late Paleozoic through the Mesozoic in the region.

  12. Three depositional states and sedimentary processes of the western Taiwan foreland basin system

    NASA Astrophysics Data System (ADS)

    Lin, Yi-Jung; Wu, Pei-Jen; Yu, Ho-Shing

    2010-05-01

    The western Taiwan foreland basin formed during the Early Pliocene as the flexural response to the loading of Taiwan orogen on the Eurasian plate. What makes Taiwan interesting is the oblique collision, which allows the foreland basin to be seen at different stages in its evolution at the present day. Due to oblique arc-continent collision from north to south, the western Taiwan foreland basin has evolved into three distinct subbasins: an over-filled basin proximal to the Taiwan orogen, mainly distributed in the Western Foothills and Coastal Plain provinces, a filled basin occupying the shallow Taiwan Strait continental shelf west of the Taiwan orogen and an under-filled basin distal to the Taiwan orogen in the deep marine Kaoping Slope offshore southwest Taiwan, respectively. The over-filled depositional phase is dominated by fluvial environments across the structurally controlled piggy-back basins. The filled depositional state in the Taiwan Strait is characterized by shallow marine environments and is filled by Pliocene-Quaternary sediments up to 4,000 m thick derived from the Taiwan orogen with an asymmetrical and wedge-shaped cross section. The under-filled depositional state is characteristic of deep marine environments in the wedge-top basins accompanied by active structures of thrust faults and mud diapers. Sediments derived from the Taiwan orogen have progressively filled the western Taiwan foreland basin across and along the orogen. Sediment dispersal model suggests that orogenic sediments derived from oblique dischronous collisional highlands are transported in two different ways. Transport of fluvial and shallow marine sediments is perpendicular to hill-slope and across-strike in the fluvial and shallow marine environments proximal to the orogen. Fine-grained sediments mainly longitudinally transported into the deep marine environments distal to the orogen. The present sedimentary processes in the over-filled basin on land are dominated by fluvial

  13. Tectonics of Chukchi Sea Shelf sedimentary basins and its influence on petroleum systems

    NASA Astrophysics Data System (ADS)

    Agasheva, Mariia; Antonina, Stoupakova; Anna, Suslova; Yury, Karpov

    2016-04-01

    The Chukchi Sea Shelf placed in the East Arctic offshore of Russia between East Siberian Sea Shelf and North Slope Alaska. The Chukchi margin is considered as high petroleum potential play. The major problem is absence of core material from drilling wells in Russian part of Chukchi Shelf, hence strong complex geological and geophysical analyses such as seismic stratigraphy interpretation should be provided. In addition, similarity to North Slope and Beaufort Basins (North Chukchi) and Hope Basin (South Chukchi) allow to infer the resembling sedimentary succession and petroleum systems. The Chukchi Sea Shelf include North and South Chukchi Basins, which are separated by Wrangel-Herald Arch and characterized by different opening time. The North Chukchi basin is formed as a general part of Canada Basin opened in Early Cretaceous. The South Chukchi Basin is characterized by a transtensional origin of the basin, this deformation related to motion on the Kobuk Fault [1]. Because seismic reflections follow chronostratigraphic correlations, it is possible to achieve stratigraphic interpretation. The main seismic horizons were indicated as: PU, JU, LCU, BU, mBU marking each regional unconformities. Reconstruction of main tectonic events of basin is important for building correct geological model. Since there are no drilling wells in the North and South Chukchi basins, source rocks could not be proven. Referring to the North Chukchi basin, source rocks equivalents of Lower Cretaceous Pebble Shale Formation, Lower Jurassic Kingdak shales and Upper Triassic Shublik Formation (North Slope) is possible exhibited [2]. In the South Chukchi, it is possible that Cretaceous source rocks could be mature for hydrocarbon generation. Erosions and uplifts that could effect on hydrocarbon preservation was substantially in Lower Jurassic and Early Cretaceous periods. Most of the structures may be connected with fault and stratigraphy traps. The structure formed at Wrangel-Herald Arch to

  14. A modern analog for carbonate source-to-sink sedimentary systems: the Glorieuses archipelago and adjacent basin (SW Indian Ocean)

    NASA Astrophysics Data System (ADS)

    Jorry, S.; Jouet, G.; Prat, S.; Courgeon, S.; Le Roy, P.; Camoin, G.; Caline, B.

    2014-12-01

    This study presents the geomorphological and sedimentological analysis of a modern carbonate source-to-sink system located north of Madagascar (SW Indian Ocean). The sedimentary system is composed of an isolated carbonate platform sited on top of a seamount rising steeply from the seabed located at 3000 m water depth. The slope of the seamount is incised by canyons, and meandering channels occur above lobbed sedimentary bodies at the foot of the slope. The dataset consists of dredges, sediment piston cores, swath bathymetry and seismic (sparker and 2D high-resolution) lines collected from inner platform (less than 5 m deep) to the adjacent deep sedimentary basin. Particle size analysis and composition of carbonate grains are used to characterize the distribution and heterogeneity of sands accumulated on the archipelago. Main results show that composition of carbonate sediments is dominated by segments of Halimeda, large benthic foraminifera, coral debris, molluscs, echinoderms, bryozoans and sponges. According to the shape and the position of sandwaves and intertidal sandbars developed in the back-barrier reef, the present organization of these well-sorted fine-sand accumulations appears to be strongly influenced by flood tidal currents. Seismic lines acquired from semi-enclosed to open lagoon demonstrate that most of the sediment is exported and accumulated along the leeward margin of the platform, which is connected to a canyon network incising the outer slope. Following the concept of highstand shedding of carbonate platforms (Schlager et al., 1994), excess sediment is exported by plumes and gravity flows to the adjacent deep sea where it feeds a carbonate deep-sea fan. Combined observations from platform to basin allow to explain how the Glorieuses carbonate source to sink system has evolved under the influence of climate and of relative sea-level changes since the last interglacial.

  15. The petroleum habitat in the post-rift sequences in the Brazilian sedimentary basins

    SciTech Connect

    De Figueiredo, A.M.F.D.; Fernandes, G.J.F.; Guimaraes, P.T.M. )

    1991-03-01

    The post-rift sedimentary strata of the Brazilian coastal basins are made of two main sequences: the evaporite and carbonatic Albian-Aptian sequence, and the open-marine Late Albian to Recent sequence, both related to the opening of the South Atlantic Ocean. More than 40 billion barrels of oil-equivalent in place has been found in these sequences, mostly in siliciclastic reservoirs above and below the Aptian salt beds. The productive basins are Campos, Espirito Santo, Sergipe-Alagoas, Potiguar, Ceara, and Santos, but the first one is responsible for more than 60% of the original oil in place discovered in these basins. The hydrocarbon origin, migration, and accumulation models in these sequences are discussed and exemplified by some giant oil fields of Campos and Sergipe-Alagoas basins, where oil is trapped in Aptian conglomerates, Albian carbonates, and Upper Cretaceous to Tertiary turbidite sandstones. The cumulative production in these sequences reaches 958.6 million barrels and the proved exploitable reserve amounts reach 2.7 billion barrels of oil-equivalent. Petrobras' exploratory forecast indicates that the post-rift sequences are the most prolific ones in the Brazilian marginal basins. The oil-equivalent that is expected to be discovered, particularly in deep water areas, where giant oil fields (as the Marlim field) have been found, exceeds the amount that has been discovered until now.

  16. Correlation between plate motions and tectonic subsidence of sedimentary basins in Africa

    SciTech Connect

    Janssen, M.E. )

    1993-09-01

    From the early Mesozoic until the Holocene, the African continent was generally in a state of extension, based on plate tectonic reconstructions and sedimentary basin subsidence studies. Beginning with the breakup of Gondwana in the Permian-Triassic, this resulted in the formation of the present-day African continental margins and a series of intracontinental rift basins, located mainly on older (late Proterozoic) shear zones. Numerous wells from marginal, as well as intracontinental rift basins, have been backstripped to elucidate their Mesozoic and Tertiary tectonic histories. They show a generally consistent patterns of subsidence and uplift phases in all basins. During the evolution of these basins, the direction of African plate motion changed several times. This was related to the differential opening of the central and south Atlantic oceans, changes in spreading rates in both the Atlantic and Indian oceans, and the collision between Africa and Europe. Episodes of compressional deformation related to these plate tectonic changes are revealed in backstripped tectonic subsidence curves.

  17. Devonian-Permian sedimentary basins and paleogeography of the Eastern Russian Arctic: An overview

    NASA Astrophysics Data System (ADS)

    Ershova, Victoria B.; Prokopiev, Andrei V.; Khudoley, Andrey K.

    2016-11-01

    The Arctic basins attract broad international interest because of the region's potentially significant undiscovered hydrocarbon resources. The Russian High Arctic is mostly represented by broad shelves, with a few wells drilled only in its western part (Kara and Barents shelves). This contribution provides an overview of the geological setting, stratigraphy, paleogeography, and tectono-sedimentary evolution of the middle-late Paleozoic basins of the Eastern Russian Arctic, including: Severnaya Zemlya, the New Siberian Islands, northern Siberia, the Taimyr and Chukotka peninsulas, and Wrangel Island. Reconstructing the geological evolution of the Eastern Russian Arctic during the middle-late Paleozoic is very difficult because the region was overprinted by a number of late Paleozoic to early Mesozoic tectonic events.

  18. Maps showing sedimentary basins, surface thermal maturity, and indications of petroleum in the Central Alaska Province

    USGS Publications Warehouse

    Troutman, Sandra M.; Stanley, Richard G.

    2003-01-01

    This publication includes two maps (at 1:2,500,000 scale) and a pamphlet that describe sedimentary basins, surface thermal maturity, and 95 reported occurrences of petroleum in natural seeps, wells, and rock outcrops in central Alaska. No commercial petroleum production has been obtained from central Alaska, in contrast to the prolific deposits of oil and gas that have been found and developed in northern Alaska and the Cook Inlet region. Nevertheless, confirmed indications of petroleum in central Alaska include (1) natural seeps of methane gas on the Yukon Delta; (2) occurrences of methane gas in wells in the Bethel, Kotzebue, Nenana, Northway, and Yukon Flats basins; (3) oil and methane gas in seeps and wells in Norton Sound; (4) small quantities of liquid and solid hydrocarbons associated with mercury ore in the Kuskokwim Mountains; (5) oil shale and numerous occurrences of bitumen in the Kandik area; and (6) tasmanite, a form of oil shale, in the uplands north of Yukon Flats.

  19. Tectonic-sedimentary evolution of the eastern Brazilian marginal basins: Implications in their petroleum systems

    SciTech Connect

    Francisco, N.F.; Azambuja, N.C.; Mello, M.R. )

    1993-02-01

    A geological survey of eastern Brazilian marginal basins using sedimentological, tectonic and geochemical data has been carried out. The almost 4000 km long set of basins can be classified as component of a typical divergent, mature Atlantic-continental margin. Based on their tectonic-sedimentary sequence, they can be linked to a single evolutionary history, which can be divided in three main stages: pre-rift, rift, and drift. The integration of all data allowed the characterization of two major petroleum systems that represent about 90% of the known Brazilian hydrocarbons reserves: (1) the rift (Early Cretaceous) and the drift (Late Cretaceous-Paleogene). With respect to the oil-in-place volume and production, the most significant one is the drift system associated with the siliciclastic deep water turbidites reservoirs deposited in bathyal environments. Such reservoirs are clearly controlled by a favorable relationship of stratigraphic and tectonic settings.

  20. Imaging three-dimensional crustal conductivity structures reflecting continental flood basalt effects hidden beneath thick intracratonic sedimentary basin

    NASA Astrophysics Data System (ADS)

    Padilha, Antonio L.; Vitorello, Ícaro; Antunes, Cassio E.; Pádua, Marcelo B.

    2015-07-01

    A large-scale array of long-period magnetic data and a deep-probing magnetotelluric profile were recorded in the intracratonic Paraná sedimentary basin in central eastern South America, which presents a thick and extensive sedimentary-magmatic sequence that allows its basement to be investigated only by indirect methods. Integration of the results from both methods showed that the crust beneath the basin presents several quasi-linear highly conductive channeled zones with limited lateral extent, in coincidence with some of the main tectonic structures recognized at the surface, and a moderate but pervasive lithosphere conductivity enhancement beneath its central part. Upward movement of CO2-bearing volatiles and magmas precipitating highly conducting mineral phases along discrete subvertical fault zones that served as feeder conduits for Early Cretaceous voluminous continental flood basalts was a likely process responsible for the localized conductivity enhancements. Correlation between some of the linear conductive zones and elongated magnetic anomalies and between the maximum depth occurrence of most of these conductive anomalies and the Curie depth at which crustal rocks lose their magnetism gives strong support to interconnected iron oxides (especially magnetite) and iron sulfides (such as pyrrhotite) as the main conductive sources. The moderate bulk conductivity increase in the crust and upper mantle beneath the central part of the basin is unexpected for a postulated cratonic basement and is tentatively associated with impregnation of the lithosphere by conducting minerals related either to widespread tectonic events in the Ordovician or Late Precambrian or to dispersed magmatic residues of an Early Cretaceous magma differentiation contaminating the entire lithosphere.

  1. Late Neogene sedimentary facies and sequences in the Pannonian Basin, Hungary

    USGS Publications Warehouse

    Juhasz, E.; Phillips, L.; Muller, P.; Ricketts, B.; Toth-Makk, A.; Lantos, M.; Kovacs, L.O.

    1999-01-01

    This paper is part of the special publication No.156, The Mediterranean basins: Tertiary extension within the Alpine Orogen. (eds B.Durand, L. Jolivet, F.Horvath and M.Seranne). Detailed sedimentological, facies and numerical cycle analysis, combined with magnetostratigraphy, have been made in a number of boreholes in the Pannonian Basin, in order to study the causes of relative water-level changes and the history of the basin subsidence. Subsidence and infilling of the Pannonian Basin, which was an isolated lake at that time occurred mainly during the Late Miocene and Pliocene. The subsidence history was remarkably different in the individual sub-basins: early thermal subsidence was interrupted in the southern part of the basin, while high sedimentation rate and continuous subsidence was detected in the northeastern sub-basin. Three regional unconformities were detected in the Late Neogene Pannonian Basin fill, which represent 0.5 and 7.5 Ma time spans corresponding to single and composite unconformities. Consequently two main sequences build up the Late Neogene Pannonian Basin fill: a Late Miocene and a Pliocene one. Within the Late Miocene sequence there are smaller sedimentary cycles most probably corresponding to climatically driven relative lake-level changes in the Milankovitch frequency band. Considering the periods, the estimated values for precession and eccentricity in this study (19 and 370 ka) are close to the usually cited ones. In the case of obliquity the calculated period (71 ka) slightly deviates from the generally accepted number. Based on the relative amplitudes of oscillations, precession (sixth order) and obliquity (fifth order) cycles had the most significant impact on the sedimentation. Eccentricity caused cycles (fourth order) are poorly detectable in the sediments. The longer term (third order) cycles had very slight influence on the sedimentation pattern. Progradation, recorded in the Late Miocene sequence, correlates poorly in time

  2. Early Permian volcano-sedimentary successions, Beishan, NW China: Peperites demonstrate an evolving rift basin

    NASA Astrophysics Data System (ADS)

    Chen, Shi; Guo, Zhaojie; Qi, Jiafu; Zhang, Yuanyuan; Pe-Piper, Georgia; Piper, David J. W.

    2016-01-01

    The Lower Permian volcano-sedimentary Zhesi Group has been investigated in the Hongliuhe and Liuyuan areas in Beishan, China, which is significant for the reconstruction of Late Paleozoic evolution in the southern part of the Central Asian Orogenic Belt. A variety of volcanic facies were distinguished in the Upper Zhesi Group: pillow basalt with interstitial limestone, thin-interbedded limestone and basalt, closely packed pillows, pillow-fragmented hyaloclastite breccia, and peperite. Laser 40Ar/39Ar whole-rock dating of the basalt yielding an age of 277 ± 11 Ma, as well as Early Permian brachiopod fossils in the limestone interbedded with the basalt, indicate that basalt was erupted in the Early Permian. The identification of the peperite and other facies originating from magma-sediment mingling reveals that the basaltic lava flows were derived from autochthonous basaltic magmatism and formed as part of the Lower Permian succession. The peperite also indicates that these subaqueous basaltic lava flows are not dismembered ophiolitic components, but formed in an autochthonous extensional setting in the Early Permian. The clastic rocks in the Lower Zhesi Group underlying the basaltic flows and peperites in the Hongliuhe and Liuyuan areas show a general fining-upwards sequence, indicating that they were deposited in a progressively deepening basin overlying the Devonian Hongliuhe suture zone. Subaqueous volcanism in a rift basin or basins, accompanied by coeval deposition of carbonate sediment and mud, built up the peperite-bearing volcanogenic-sedimentary successions. From among the various tectonic hypotheses for the Beishan region, this study demonstrates that by Early Permian the region was developing post-collisional rift basins.

  3. Sedimentary facies and depositional environments of early Mesozoic Newark Supergroup basins, eastern North America

    USGS Publications Warehouse

    Smoot, J.P.

    1991-01-01

    The early Mesozoic Newark Supergroup consists of continental sedimentary rocks and basalt flows that occupy a NE-trending belt of elongate basins exposed in eastern North America. The basins were filled over a period of 30-40 m.y. spanning the Late Triassic to Early Jurassic, prior to the opening of the north Atlantic Ocean. The sedimentary rocks are here divided into four principal lithofacies. The alluvial-fan facies includes deposits dominated by: (1) debris flows; (2) shallow braided streams; (3) deeper braided streams (with trough crossbeds); or (4) intense bioturbation or hyperconcentrated flows (tabular, unstratified muddy sandstone). The fluvial facies include deposits of: (1) shallow, ephemeral braided streams; (2) deeper, flashflooding, braided streams (with poor sorting and crossbeds); (3) perennial braided rivers; (4) meandering rivers; (5) meandering streams (with high suspended loads); (6) overbank areas or local flood-plain lakes; or (7) local streams and/or colluvium. The lacustrine facies includes deposits of: (1) deep perennial lakes; (2) shallow perennial lakes; (3) shallow ephemeral lakes; (4) playa dry mudflats; (5) salt-encrusted saline mudflats; or (6) vegetated mudflats. The lake margin clastic facies includes deposits of: (1) birdfoot deltas; (2) stacked Gilbert-type deltas; (3) sheet deltas; (4) wave-reworked alluvial fans; or (5) wave-sorted sand sheets. Coal deposits are present in the lake margin clastic and the lacustrine facies of Carnian age (Late Triassic) only in basins of south-central Virginia and North and South Carolina. Eolian deposits are known only from the basins in Nova Scotia and Connecticut. Evaporites (and their pseudomorphs) occur mainly in the northern basins as deposits of saline soils and less commonly of saline lakes, and some evaporite and alkaline minerals present in the Mesozoic rocks may be a result of later diagenesis. These relationships suggest climatic variations across paleolatitudes, more humid to the

  4. The supra-detachment tectono-sedimentary record of rifted margins: the example of the Los Barriles Basin, SE Baja California Sur.

    NASA Astrophysics Data System (ADS)

    Masini, Emmanuel; Robin, Cécile; Geoffroy, Laurent; Strzerzynski, Pierre

    2010-05-01

    The study of rifted margins have shown that the main controlling structures are changing from classical high-angle faults to low-angle detachment fault dominated extension when the crust thins to less than 10 km, which is the case in hyper-extended, magma-poor rifted margins. While the stratigraphic record related to classical high-angle faulting is well constrained, little is known about the tectono-sedimentary evolution of hyper-extended rift systems. A major question remains, how supra-detachment tectono-sedimentary systems are recorded in the stratigraphic record? This remains largely unexplored and must be better constrained by observations. In our poster, we present preliminary results from our study of a rift basin floored by a low-angle detachment system exposed at the southeastern edge of the Baja California Peninsula in the so-called Los Barriles area in the Gulf of California. This area represents one of the best examples of an active transtensional rift system from which the tectono-sedimentary evolution of the rift to drift transition can be studied in the field. The syn-tectonic sedimentary sequence is floored by a detachment fault and is limited oceanward by an extensional allochthon. The syn- to post-tectonic stratigraphy can be summarized into 4 main formations: (1) The Pescadero fluvial fm. (no available ages) evolves upsection from poorly organized polymictic in components and faulted breccias to more granitic and stratified conglomerates. It overlies the extensional allochthon and is tilted continentwards. The channel incisions show EW paleoflows and the upper Pescadero fm. is transitional to the following Refugio fm. (2) The overlying Refugio fm. (Lower Pliocene) occurs as thick marine sandy deposits within the basin axis, is granitic in composition and has average paleocurrents directions trending N-S. The upper part of the fm. is transitional to the following Barriles fm. (3) The Barriles fm. (Upper Miocene - Lower Pleistocene) occurs as very

  5. The structure and stratigraphy of the sedimentary succession in the Swedish sector of the Baltic Basin: New insights from vintage 2D marine seismic data

    NASA Astrophysics Data System (ADS)

    Sopher, Daniel; Erlström, Mikael; Bell, Nicholas; Juhlin, Christopher

    2016-04-01

    We present five interpreted regional seismic profiles, describing the full sedimentary sequence across the Swedish sector of the Baltic Sea. The data for the study are part of an extensive and largely unpublished 2D seismic dataset acquired between 1970 and 1990 by the Swedish Oil Prospecting Company (OPAB). The Baltic Basin is an intracratonic basin located in northern Europe. Most of the Swedish sector of the basin constitutes the NW flank of a broad synclinal depression, the Baltic Basin. In the SW of the Swedish sector lies the Hanö Bay Basin, formed by subsidence associated with inversion of the Tornquist Zone during the Late Cretaceous. The geological history presented here is broadly consistent with previously published works. We observe an area between the Hanö Bay and the Baltic Basin where the Palaeozoic strata has been affected by transpression and subsequent inversion, associated with the Tornquist Zone during the late Carboniferous-Early Permian and Late Cretaceous, respectively. We propose that the Christiansø High was a structural low during the Late Jurassic, which was later inverted in the Late Cretaceous. We suggest that a fan shaped feature in the seismic data, adjacent to the Christiansø Fault within the Hanö Bay Basin, represents rapidly deposited, coarse-grained sediments eroded from the inverted Christiansø High during the Late Cretaceous. We identify a number of faults within the deeper part of the Baltic Basin, which we also interpret to be transpressional in nature, formed during the Caledonian Orogeny in the Late Silurian-Early Devonian. East of Gotland a number of sedimentary structures consisting of Silurian carbonate reefs and Ordovician carbonate mounds, as well as a large Quaternary glacial feature are observed. Finally, we use the seismic interpretation to infer the structural and stratigraphic history of the Baltic and Hanö Bay basins within the Swedish sector.

  6. Modeling of wind gap formation and development of sedimentary basins during fold growth: application to the Zagros Fold Belt, Iran.

    NASA Astrophysics Data System (ADS)

    Collignon, Marine; Yamato, Philippe; Castelltort, Sébastien; Kaus, Boris

    2016-04-01

    Mountain building and landscape evolution are controlled by the interactions between river dynamics and tectonic forces. Such interactions have been largely studied but a quantitative evaluation of tectonic/geomorphic feedbacks remains required for understanding sediments routing within orogens and fold-and-thrust belts. Here, we employ numerical simulations to assess the conditions of uplift and river incision necessary to deflect an antecedent drainage network during the growth of one or several folds. We propose that a partitioning of the river network into internal (endorheic) and longitudinal drainage arises as a result of lithological differences within the deforming crustal sedimentary cover. We show with examples from the Zagros Fold Belt (ZFB) that drainage patterns can be linked to the incision ratio R between successive lithological layers, corresponding to the ratio between their relative erodibilities or incision coefficients. Transverse drainage networks develop for uplift rates smaller than 0.8 mm.yr-1 and -10 < R < 10. Intermediate drainage network are obtained for uplift rates up to 2 mm.yr-1 and incision ratios of 20. Parallel drainage networks and formation of sedimentary basins occur for large values of incision ratio (R >20) and uplift rates between 1 and 2 mm.yr-1. These results have implications for predicting the distribution of sediment depocenters in fold-and-thrust belts, which can be of direct economic interest for hydrocarbon exploration.

  7. Shelf-edge sedimentary systems off Rio de Janeiro State, northern Santos basin-Brazil

    NASA Astrophysics Data System (ADS)

    Maia, R. M. C.; Dos Reis, A. T.; Gorini, C.; Silva, C. G.; Rabineau, M.; Granjeon, D.

    2012-04-01

    elements provide a hint at a prevailing subsidence regime and effective sediment supply into the basin that clearly contrast with the conveyed idea of a sediment-starved and tectonic stable shelf. They naturally raise questions about the nature and origin of sediment supply, since no significant point siliciclastic fluvial source flows directly into the shelf. Stemming from that, we are forced to speculate about: (A) the role of neotectonic movements involving the Serra do Mar coastal mountain ranges to potentially source clastic influx into the basin during the Quaternary, or about the real importance of secondary drainage basins debouching today; and (B) the mechanical nature of a supposed subsidence during the Pliocene and the Quaternary time span (overloading ? sediment compaction ? thermal cooling ?). The interpretation of industrial seismic lines can provide the answers of many of these questions. The next step of this work is to make a stratigraphy model of the sedimentary systems of Santos basin to understand how the ancient creation of accommodation space can influence the recent sedimentary architecture and how is the change in sedimentary influx and the sedimentary records of different orders of cyclicity.

  8. Geodynamic evolution and sedimentary infill of the northern Levant Basin: A source to sink-perspective

    NASA Astrophysics Data System (ADS)

    Hawie, N.

    2013-12-01

    Nicolas Hawie a,b,c (nicolas.hawie@upmc.fr) Didier Granjeon c (didier.granjeon@ifpen.fr) Christian Gorini a,b (christian.gorini@upmc.fr) Remy Deschamps c (remy.deschamps@ifpen.fr) Fadi H. Nader c (fadi-henri.nader@ifpen.fr) Carla Müller Delphine Desmares f (delphine.desmares@upmc.fr) Lucien Montadert e (lucien.montadert@beicip.com) François Baudin a (francois.baudin@upmc.fr) a UMR 7193 Institut des Sciences de la Terre de Paris, Université Pierre et Marie Curie/ Univ. Paris 06, case 117. 4, place Jussieu 75252 Paris Cedex 05, France b iSTEP, UMR 7193, CNRS, F-75005, Paris, France c IFP Energies nouvelles, 1-4 avenue du Bois Préau 92852 Rueil Malmaison Cedex, France d UMR 7207, Centre de Recherche sur la Paleobiodiversité et les Paleoenvironnements. Université Pierre et Marie Curie, Tour 46-56 5ème. 4, place Jussieu 75252 Paris Cedex 05, France e Beicip Franlab, 232 Av. Napoléon Bonaparte, 95502 Rueil-Malmaison, France Sedimentological and biostratigraphic investigations onshore Lebanon coupled with 2D offshore reflection seismic data allowed proposing a new Mesozoic-Present tectono-stratigraphic framework for the northern Levant Margin and Basin. The seismic interpretation supported by in-depth facies analysis permitted to depict the potential depositional environments offshore Lebanon as no well has yet been drilled. The Levant region has been affected by successive geodynamic events that modified the architecture of its margin and basin from a Late Triassic to Middle Jurassic rift into a Late Cretaceous subduction followed by collision and Miocene-Present strike slip motion. The interplay between major geodynamic events as well as sea level fluctuations impacted on the sedimentary infill of the basin. During Jurassic and Cretaceous, the Levant Margin is dominated by the aggradation of a carbonate platform while deepwater mixed-systems prevailed in the basin. During the Oligo-Miocene, three major sedimentary pathways are expected to drive important

  9. Radiogenic heat production in sedimentary rocks of the Gulf of Mexico Basin, south Texas

    USGS Publications Warehouse

    McKenna, T.E.; Sharp, J.M.

    1998-01-01

    Radiogenic heat production within the sedimentary section of the Gulf of Mexico basin is a significant source of heat. Radiogenic heat should be included in thermal models of this basin (and perhaps other sedimentary basins). We calculate that radiogenic heat may contribute up to 26% of the overall surface heat-flow density for an area in south Texas. Based on measurements of the radioactive decay rate of ??-particles, potassium concentration, and bulk density, we calculate radiogenic heat production for Stuart City (Lower Cretaceous) limestones, Wilcox (Eocene) sandstones and mudrocks, and Frio (Oligocene) sandstones and mudrocks from south Texas. Heat production rates range from a low of 0.07 ?? 0.01 ??W/m3 in clean Stuart City limestones to 2.21 ?? 0.24??W/m3 in Frio mudrocks. Mean heat production rates for Wilcox sandstones, Frio sandstones, Wilcox mudrocks, and Frio mudrocks are 0.88, 1.19, 1.50, and 1.72 ??W/m3, respectively. In general, the mudrocks produce about 30-40% more heat than stratigraphically equivalent sandstones. Frio rocks produce about 15% more heat than Wilcox rocks per unit volume of clastic rock (sandstone/mudrock). A one-dimensional heat-conduction model indicates that this radiogenic heat source has a significant effect on subsurface temperatures. If a thermal model were calibrated to observed temperatures by optimizing basal heat-flow density and ignoring sediment heat production, the extrapolated present-day temperature of a deeply buried source rock would be overestimated.Radiogenic heat production within the sedimentary section of the Gulf of Mexico basin is a significant source of heat. Radiogenic heat should be included in thermal models of this basin (and perhaps other sedimentary basins). We calculate that radiogenic heat may contribute up to 26% of the overall surface heat-flow density for an area in south Texas. Based on measurements of the radioactive decay rate of ??-particles, potassium concentration, and bulk density, we

  10. Uncertainty quantification of overpressure buildup through inverse modeling of compaction processes in sedimentary basins

    NASA Astrophysics Data System (ADS)

    Colombo, Ivo; Porta, Giovanni M.; Ruffo, Paolo; Guadagnini, Alberto

    2016-11-01

    This study illustrates a procedure conducive to a preliminary risk analysis of overpressure development in sedimentary basins characterized by alternating depositional events of sandstone and shale layers. The approach rests on two key elements: (1) forward modeling of fluid flow and compaction, and (2) application of a model-complexity reduction technique based on a generalized polynomial chaos expansion (gPCE). The forward model considers a one-dimensional vertical compaction processes. The gPCE model is then used in an inverse modeling context to obtain efficient model parameter estimation and uncertainty quantification. The methodology is applied to two field settings considered in previous literature works, i.e. the Venture Field (Scotian Shelf, Canada) and the Navarin Basin (Bering Sea, Alaska, USA), relying on available porosity and pressure information for model calibration. It is found that the best result is obtained when porosity and pressure data are considered jointly in the model calibration procedure. Uncertainty propagation from unknown input parameters to model outputs, such as pore pressure vertical distribution, is investigated and quantified. This modeling strategy enables one to quantify the relative importance of key phenomena governing the feedback between sediment compaction and fluid flow processes and driving the buildup of fluid overpressure in stratified sedimentary basins characterized by the presence of low-permeability layers. The results here illustrated (1) allow for diagnosis of the critical role played by the parameters of quantitative formulations linking porosity and permeability in compacted shales and (2) provide an explicit and detailed quantification of the effects of their uncertainty in field settings.

  11. Uncertainty quantification of overpressure buildup through inverse modeling of compaction processes in sedimentary basins

    NASA Astrophysics Data System (ADS)

    Colombo, Ivo; Porta, Giovanni M.; Ruffo, Paolo; Guadagnini, Alberto

    2017-03-01

    This study illustrates a procedure conducive to a preliminary risk analysis of overpressure development in sedimentary basins characterized by alternating depositional events of sandstone and shale layers. The approach rests on two key elements: (1) forward modeling of fluid flow and compaction, and (2) application of a model-complexity reduction technique based on a generalized polynomial chaos expansion (gPCE). The forward model considers a one-dimensional vertical compaction processes. The gPCE model is then used in an inverse modeling context to obtain efficient model parameter estimation and uncertainty quantification. The methodology is applied to two field settings considered in previous literature works, i.e. the Venture Field (Scotian Shelf, Canada) and the Navarin Basin (Bering Sea, Alaska, USA), relying on available porosity and pressure information for model calibration. It is found that the best result is obtained when porosity and pressure data are considered jointly in the model calibration procedure. Uncertainty propagation from unknown input parameters to model outputs, such as pore pressure vertical distribution, is investigated and quantified. This modeling strategy enables one to quantify the relative importance of key phenomena governing the feedback between sediment compaction and fluid flow processes and driving the buildup of fluid overpressure in stratified sedimentary basins characterized by the presence of low-permeability layers. The results here illustrated (1) allow for diagnosis of the critical role played by the parameters of quantitative formulations linking porosity and permeability in compacted shales and (2) provide an explicit and detailed quantification of the effects of their uncertainty in field settings.

  12. High-resolution seismic imaging of the Sohagpur Gondwana basin, central India: Evidence for syn-sedimentary subsidence and faulting

    NASA Astrophysics Data System (ADS)

    Dhanam, K.; Kumar, P. Senthil; Mysaiah, D.; Prasad, P. Prabhakara; Seshunarayana, T.

    2013-12-01

    Gondwana sedimentary basins in the Indian Shield preserve a rich record of tectonic, sedimentary and volcanic processes that affected Gondwanaland. The Gondwana rocks were deposited in the linear rift basins that were formed during Permian-Cretaceous time, similar to their neighbours in Australia, Africa and Antarctica. In this study, we illustrate how Gondwana tectonics affected the Sohagpur Gondwana basin that occurs at the junction of the Mahanadi and Son-Narmada rift systems in the central India, through a high-resolution seismic reflection study along six profiles, covering the central part of the Sohagpur basin. The study reveals (1) ˜1000 m thick, gently dipping Barakar Formation, (2) thick coal seams at a depth of 350-550 m, and (3) NNW-SSE to NW-SE striking steeply dipping normal faults defining rift geometry. These results indicate that the Sohagpur basin contains a thick Lower Gondwana sedimentary succession with a high potential of coal resources and were affected by extensional tectonics. The rift structure in the study area is a syn- to post-sedimentary deformational structure that was formed arguably in response to tectonics that pervasively affected Gondwanaland.

  13. Tectonics and petroleum potential of sedimentary basins in the Bering, Okhotsk, Japan seas, and island arcs

    SciTech Connect

    Levin, L.E. )

    1993-09-01

    In this vast region located in the northwestern part of the Pacific rim, basins of two main genetic types possess petroleum potential. These two types are represented by basins of the recent active margin and basins of the transitional zone between analogs of the passive margin and the recent active margin. For basins of the active margin, the mean density of potential resources is estimated at 5000 MT/km[sup 2] or more. The total area of these basins is 324,000 km[sup 2] among which 120,000 km[sup 2] are in the Russian sector. Ultimate resources of hydrocarbons are estimated at 1.62 billing MT of oil equivalent. Basins of the zone, transitional from analogs of the passive margin to the recent active margin, are characterized by a number of factors favorable for petroleum occurrence. One of the important factors is the presence of rift trough and foredeeps that are potential sites for zones of oil and gas accumulation. The age of the rifts varies from the late Cretaceous through the Oligocene-Miocene in the Olyutorsky and Litke basins, to the Neogene in the Okhotsk Sea and Tatar-Japan basins. Only a small area of the rifts has been proven to contain zones of oil and gas accumulation. Based on the structural characteristics, the rifts are subdivided into oil-gas bearing, potentially oil-gas bearing, and nonprospective for hydrocarbon exploration. Potential hydrocarbon resources of basins of this type are estimated to be not less than 15.12 billion MT of oil equivalent including 9.2 billion MT in the Russian sector. New large zones of oil and gas accumulation are expected to be found both on the shallow shelf and in some deep-water basins such as in the Aleutian and Kuril basins.

  14. Palynostratigraphy and sedimentary facies of Middle Miocene fluvial deposits of the Amazonas Basin, Brazil

    NASA Astrophysics Data System (ADS)

    Dino, Rodolfo; Soares, Emílio Alberto Amaral; Antonioli, Luzia; Riccomini, Claudio; Nogueira, Afonso César Rodrigues

    2012-03-01

    Palynostratigraphic and sedimentary facies analyses were made on sedimentary deposits from the left bank of the Solimões River, southwest of Manaus, State of Amazonas, Brazil. These provided the age-dating and subdivision of a post-Cretaceous stratigraphic succession in the Amazonas Basin. The Novo Remanso Formation is subdivided into upper and lower units, and delineated by discontinuous surfaces at its top and bottom. The formation consists primarily of sandstones and minor mudstones and conglomerates, reflecting fluvial channel, point bar and floodplain facies of a fluvial meandering paleosystem. Fairly well-preserved palynoflora was recovered from four palynologically productive samples collected in a local irregular concentration of gray clay deposits, rich in organic material and fossilized wood, at the top of the Novo Remanso Formation upper unit. The palynoflora is dominated by terrestrial spores and pollen grains, and is characterized by abundant angiosperm pollen grains ( Tricolpites, Grimsdalea, Perisyncolporites, Tricolporites and Malvacearumpollis). Trilete spores are almost as abundant as the angiosperm pollen, and are represented mainly by the genera Deltoidospora, Verrutriletes, and Hamulatisporis. Gymnosperm pollen is scarce. The presence of the index species Grimsdalea magnaclavata Germeraad et al. (1968) indicates that these deposits belong to the Middle Miocene homonymous palynozone (Lorente, 1986; Hoorn, 1993; Jaramillo et al., 2011). Sedimentological characteristics (poorly sorted, angular to sub-angular, fine to very-coarse quartz sands facies) are typical of the Novo Remanso Formation upper part. These are associated with a paleoflow to the NE-E and SE-E, and with an entirely lowland-derived palinofloristic content with no Andean ferns and gymnosperms representatives. All together, this suggests a cratonic origin for this Middle Miocene fluvial paleosystem, which was probably born in the Purus Arch eastern flank and areas surrounding the

  15. Potential leakage between aquifers in a deeply anthropized coastal sedimentary basin (Recife, Brazil): Strontium isotope constraints

    NASA Astrophysics Data System (ADS)

    Petelet-Giraud, Emmanuelle; Cary, Lise; Hirata, Ricardo; Martins, Veridiana; Bertrand, Guillaume; Montenegro, Suzana; Pauwels, Helene; Kloppmann, Wolfram; Aquilina, Luc

    2013-04-01

    Due to an increasing demographic pressure, the Metropolitan Region of Recife (RMR) went through remarkable changes of water and land uses over the last decades. These evolutions gave rise to numerous environmental consequences, such as a dramatic decline of the piezometric levels, groundwater salinization and contamination. This degradation of natural resources is linked to the increase of water demand, punctually amplified by drought periods which induced the construction of thousands of private wells. Recife was built on the estuarine area of the Capibaribe River and other small rivers. The Recife coastal plain is located in the geographic limits of the sedimentary basins of Cabo and Pernambuco-Paraíba which consist out of fluvial and marine geologic formations. It is composed of three main aquifers: the two semi-confined Cabo and Beberibe aquifers, both underlining the superficial Boa Viagem unconfined aquifer, which is the most directly exposed to contamination, since it is connected to mangroves, rivers, estuaries and highly urbanized areas. The Boa Viagem aquifer is made of marine terraces of sand, silt and clay has an average thickness of 40 m. The Cabo aquifer occurs in the south of Recife and comprises sandstones, siltstones and mudstones, with an average thickness of 90 m. The Beberibe aquifer occurs in the north and central area of Recife with an average thickness of 100 m of sandstones with intercalations of mudstone; it is the most important one, with the highest amount of good quality water. Both the Beberibe and Cabo aquifers contain large clay levels. The hydraulic connections between the three aquifers are not well known but isotopic studies have shown that the recharge processes are similar, suggesting that exchanges may occur and may be modified or amplified by overexploitation especially between the Cabo and Boa Viagem aquifers. Two other aquifers can be found west of the city: the Barreiras aquifer, characterized by alternating well stratified

  16. Trace element characteristics of graywackes and tectonic setting discrimination of sedimentary basins

    NASA Astrophysics Data System (ADS)

    Bhatia, Mukul R.; Crook, Keith A. W.

    1986-02-01

    The graywackes of Paleozoic turbidite sequences of eastern Australia show a large variation in their trace element characteristics, which reflect distinct provenance types and tectonic settings for various suites. The tectonic settings recognised are oceanic island arc, continental island arc, active continental margin, and passive margins. Immobile trace elements, e.g. La, Ce, Nd, Th, Zr, Nb, Y, Sc and Co are very useful in tectonic setting discrimination. In general, there is a systematic increase in light rare earth elements (La, Ce, Nd), Th, Nb and the Ba/Sr, Rb/Sr, La/Y and Ni/Co ratios and a decrease in V, Sc and the Ba/Rb, K/Th and K/U ratios in graywackes from oceanic island arc to continental island arc to active continental margin to passive margin settings. On the basis of graywacke geochemistry, the optimum discrimination of the tectonic settings of sedimentary basins is achieved by La-Th, La-Th-Sc, Ti/Zr-La/Sc, La/Y-Sc/Cr, Th-Sc-Zr/10 and Th-Co-Zr/10 plots. The analysed oceanic island arc graywackes are characterised by extremely low abundances of La, Th, U, Zr, Nb; low Th/U and high La/Sc, La/Th, Ti/Zr, Zr/Th ratios. The studied graywackes of the continental island arc type setting are characterised by increased abundances of La, Th, U, Zr and Nb, and can be identified by the La-Th-Sc and La/Sc versus Ti/Zr plots. Active continental margin and passive margin graywackes are discriminated by the Th-Sc-Zr/10 and Th-Co-Zr/10 plots and associated parameters (e.g. Th/Zr, Th/Sc). The most important characteristic of the analysed passive margin type graywackes is the increased abundance of Zr, high Zr/Th and lower Ba, Rb, Sr and Ti/Zr ratio compared to the active continental margin graywackes.

  17. Distributed model of hydrological and sediment transport processes in large river basins in Southeast Asia

    NASA Astrophysics Data System (ADS)

    Zuliziana, S.; Tanuma, K.; Yoshimura, C.; Saavedra, O. C.

    2015-07-01

    Soil erosion and sediment transport have been modeled at several spatial and temporal scales, yet few models have been reported for large river basins (e.g., drainage areas > 100 000 km2). In this study, we propose a process-based distributed model for assessment of sediment transport at a large basin scale. A distributed hydrological model was coupled with a process-based distributed sediment transport model describing soil erosion and sedimentary processes at hillslope units and channels. The model was tested on two large river basins: the Chao Phraya River Basin (drainage area: 160 000 km2) and the Mekong River Basin (795 000 km2). The simulation over 10 years showed good agreement with the observed suspended sediment load in both basins. The average Nash-Sutcliffe efficiency (NSE) and average correlation coefficient (r) between the simulated and observed suspended sediment loads were 0.62 and 0.61, respectively, in the Chao Phraya River Basin except the lowland section. In the Mekong River Basin, the overall average NSE and r were 0.60 and 0.78, respectively. Sensitivity analysis indicated that suspended sediment load is sensitive to detachability by raindrop (k) in the Chao Phraya River Basin and to soil detachability over land (Kf) in the Mekong River Basin. Overall, the results suggest that the present model can be used to understand and simulate erosion and sediment transport in large river basins.

  18. A MATLAB®-based program for 3D visualization of stratigraphic setting and subsidence evolution of sedimentary basins: example application to the Vienna Basin

    NASA Astrophysics Data System (ADS)

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

    2015-04-01

    In recent years, 3D visualization of sedimentary basins has become increasingly popular. Stratigraphic and structural mapping is highly important to understand the internal setting of sedimentary basins. And subsequent subsidence analysis provides significant insights for basin evolution. This study focused on developing a simple and user-friendly program which allows geologists to analyze and model sedimentary basin data. The developed program is aimed at stratigraphic and subsidence modelling of sedimentary basins from wells or stratigraphic profile data. This program is mainly based on two numerical methods; surface interpolation and subsidence analysis. For surface visualization four different interpolation techniques (Linear, Natural, Cubic Spline, and Thin-Plate Spline) are provided in this program. The subsidence analysis consists of decompaction and backstripping techniques. The numerical methods are computed in MATLAB® which is a multi-paradigm numerical computing environment used extensively in academic, research, and industrial fields. This program consists of five main processing steps; 1) setup (study area and stratigraphic units), 2) loading of well data, 3) stratigraphic modelling (depth distribution and isopach plots), 4) subsidence parameter input, and 5) subsidence modelling (subsided depth and subsidence rate plots). The graphical user interface intuitively guides users through all process stages and provides tools to analyse and export the results. Interpolation and subsidence results are cached to minimize redundant computations and improve the interactivity of the program. All 2D and 3D visualizations are created by using MATLAB plotting functions, which enables users to fine-tune the visualization results using the full range of available plot options in MATLAB. All functions of this program are illustrated with a case study of Miocene sediments in the Vienna Basin. The basin is an ideal place to test this program, because sufficient data is

  19. Hydraulic characteristics of the Maastrichtian sedimentary rocks of the southeastern Bida Basin, central Nigeria

    NASA Astrophysics Data System (ADS)

    Vrbka, Petr; Ojo, Olusola Johnson; Gebhardt, Holler

    1999-12-01

    A set of outcrop samples from the Lokoja and Patti Formations of the southern Bida Basin (Nigeria) was examined for grain size distribution, sedimentary and hydraulic characteristics. Most of the samples are well-sorted with an uniformity coefficient (U) ranging between 1.3 and 6.3. The mean effective grain diameter (d 10) is in the order of 0.11 mm, the mean value of d 90 was determined as 0.66 mm (both geometric mean) and the median grain size (d 50) as 0.23 mm. Based on these values, the sedimentary sequence can be described as 'fine to medium sized sand', having minor amounts of either silt, or coarse sand and some gravel. The total porosity of the samples was determined by laboratory methods to be in the range of 9-29%. The hydraulic conductivity (K) was determined according to Hazen.and Beyer, and by Shepherd's formula, the last resulting in a geometric mean of 3.3 m d -1 or 3.3 darcy. The results are used to estimate local groundwater potential. The entire pore space (potential groundwater reservoir) for the area under study is estimated to be in the order of 290-430 km 3. Because of higher hydraulic conductivities, it is recommended that the Lokoja Formation is concentrated on as a target for groundwater exploration.

  20. A sedimentary paleomagnetic record of the upper Jaramillo transition from the Lantian Basin in China

    NASA Astrophysics Data System (ADS)

    Wu, Yi; Ouyang, Tingping; Qiu, Shifan; Rao, Zhiguo; Zhu, Zhaoyu

    2015-10-01

    The termination of the Jaramillo (normal to reverse) subchron is a key chronostratigraphic marker for dating global Pleistocene sedimentary sequences. However, the stratigraphic position of the geomagnetic polarity reversal varies greatly across the Chinese Loess Plateau (CLP), from near the bottom of paleosol unit S9 to the middle-upper part of S10. Here, we present paleomagnetic and rock magnetic results from high-resolution sampling of the Yushan loess section of the Lantian Basin located within the southern CLP. Our combined analyses determine that the polarity reversal is located in the middle-lower part of the paleosol unit S10. This stratigraphic position is lower than most of other studies conducted throughout the CLP. We attribute the difference in the location of the reversal to a deeper lock-in depth of remanence acquisition, which may have occurred from postdepositional processes under favorable hydrothermal conditions along the southern margin of CLP. It is important to note that age determinations through magnetic stratigraphy on sedimentary sections, particularly in discontinuous and/or imperfect sequences, should be treated with caution; there are significant differences with respect to the location of the polarity reversal throughout the CLP.

  1. Estimation of Sedimentary Thickness in Kachchh Basin, Gujarat Using SP Converted Phase

    NASA Astrophysics Data System (ADS)

    Chopra, Sumer; Rao, K. M.; Rastogi, B. K.

    2010-10-01

    An inexpensive method using natural earthquake data is utilized for determining the sedimentary thickness in Kachchh. The Institute of Seismological Research (ISR) is operating a network of broadband seismographs and strong motion accelerographs in Gujarat. We used data from 13 broadband seismographs and two strong motion accelerographs in the study. The stations are within 5 to 80 km from the epicenters. In this study the S-to-P converted phase, SP, is used. This phase is generated due to large impedance contrast between sediments and basement. This phase is clear in the vertical component. The difference in the travel times of S and SP phases and velocities of P and S waves is used for determining the sedimentary layer thickness. The thickness of sediments beneath each of these 15 stations was determined covering an area of 23,500 sq km.

  2. Magnetostratigraphy of the middle-upper Jurassic sedimentary sequences at Yanshiping, Qiangtang Basin, China

    NASA Astrophysics Data System (ADS)

    Song, Chunhui; Zeng, Yongyao; Yan, Maodu; Wu, Song; Fang, Xiaomin; Bao, Jing; Zan, Jinbo; Liu, Xifang

    2016-09-01

    A series of important geological events occurred in the Tibetan Plateau area during the Jurassic, such as the collision of the Lhasa and Qiangtang Terranes, the closure of the Meso-Tethyan Ocean, the opening of the Neo-Tethyan Ocean and the cessation of the mega-monsoon. The ˜3000 m thick Jurassic sedimentary sequence in the Qiangtang Basin on the central Tibetan Plateau, which is called the Yanshiping (YSP) Group, recorded these geological events. However, the chronology of the sequence is surprisingly poorly constrained. Here, we perform a detailed palaeomagnetic analysis on the ˜1060 m thick middle and upper portions of the YSP Group (the Xiali and Suowa Formations) in the YSP section of the eastern Qiangtang Basin. Three bivalve zones at stratigraphic intervals of ˜40-140, 640-800 and 940-1040 m are identified, which yield a Bathonian-Callovian age for the Lower Xiali Fm., a Callovian-Oxfordian age for the Lower Suowa Fm. and an Oxfordian-Kimmeridgian age for the Upper Suowa Fm. A total of 544 oriented palaeomagnetic samples were collected from the section. By combining thermal and alternating field demagnetizations, clear characteristic remanent magnetization (ChRM) directions are isolated for most of the samples. The robust ChRM directions pass fold and reversals tests, which support the primary nature of the ChRMs and yield a palaeopole at 76.8°N/297.2°E (dp = 2.2°, dm = 3.7°). A total of 27 normal and 26 reversed polarity zones were successfully recorded in the section. Combined with fossil age constraints, results suggest that the section is plausibly composed of a Callovian-Early Kimmeridgian age sedimentary sequence.

  3. Large slope failures in the La Paz basin, Bolivian Andes

    NASA Astrophysics Data System (ADS)

    Roberts, N. J.; Hermanns, R. L.; Rabus, B.; Guzmán, M. A.; Minaya, E.; Clague, J. J.

    2014-12-01

    The La Paz basin in the eastern Bolivian Andes has been a hotspot for large-scale, deep-seated gravitational slope deformation during the Holocene. In less than 2 Ma, a network of steep-sided valleys up to 800 m deep formed in sediments of the Altiplano Plateau and underlying basement rocks. We characterize the distribution, extent, mechanisms, and modern activity of large-scale failures within this landscape using optical image interpretation, existing geologic maps, synthetic RADAR interferometry (InSAR), and field investigation. Deposits of nearly 20 landslides larger than 100 Mm3 occur within the basin. Most failures have occurred in weakly lithified Late Miocene to Pliocene sedimentary rocks and include earth flows, translational and rotational landslides, and plug flows. Failures in underlying tectonized Paleozoic sedimentary rocks include bedding-parallel rockslides. The largest failure is the 3 km3 Achcocalla earth flow (ca. 11 ka BP), which ran out ~20 km. Other dated events span the period from the early Holocene to nearly the Colonial historic period. InSAR results show that many large slope failures, including the Achocalla earth flow, are currently moving at rates of a few centimeters to a few decimeters per year. Rapid deposition, shallow burial, and rapid incision of the basin fills produced steep slopes in weak geologic materials that, coupled with groundwater discharge from the valley walls, are the primary controls on instability. In contrast, the Altiplano surface has changed little in 2 Ma and the adjacent slopes of the Cordilleran Real, although steep, are relatively stable. Of the over 100 landslides that have occurred in the city of La Paz since the early twentieth century, most are at the margins of large, deep-seated prehistoric failures, and two of the most damaging historic landslides (Hanko-Hanko, 1582; Pampahasi, 2011) were large-scale reactivations of previously failed slopes. Improved understanding of large, deep-seated landslides in

  4. Sedimentology and Sedimentary Dynamics of the Desmoinesian Cherokee Group, Deep Anadarko Basin, Texas Panhandle

    NASA Astrophysics Data System (ADS)

    Hu, N.; Loucks, R.; Frebourg, G.

    2015-12-01

    Understanding the spatial variability of deep-water facies is critical to deep-water research because of its revealing information about the relationship between desity flow processes and their resultant sedimentary sequences. The Cherokee Group in the Anadarko Basin, northeastern Texas Panhandle, provides an opportunity to investigate an icehouse-greenhouse Pennsylvanian hybrid system that well demonstrates the intricacies of vertical and lateral facies relationships in an unconfined fan-delta fed deep-water slope to basinal setting. The stratigraphic section ranges in thickness from 150 to 460 m. The cyclic sedimentation and foreland basin tectonics resulted in a complex stratal architecture that was sourced by multiple areas of sediment input. This investigation consists of wireline-log and core data. Five-thousand wireline logs were correlated in an area of over 9500 sq km to map out six depositional sequences that are separated by major flooding events. These events are correlative over the whole area of study. Six cores, that sample nearly the complete section, were described for lithofacies. Lithofacies are recognized based on depositional features and mineralogy:(1) Subarkose, (2) Lithicarkoses, (3) Sandy siliciclastic conglomerate, (4) Muddy calcareous conglomerate, (5) Crinoidal packstone, (6) Oodic grainstone, (7)Pelodic grainstone, (8) Ripple laminated mudrock, (9) faint laminated mudrock. The integration of isopachs of depositional sequences with the lithofacies has allowed the delineation of the spatial and temporal evolution of the slope to basin-floor system. Thin-to-thick bedded turbidites, hyperconcentrated density flow deposits (slurry beds), and debris and mud flow deposits were observed and can be used to better predicte lithofacies distributions in areas that have less data control. These mixed siliciclastic and carbonate deposits can be carrier beds for the hydrocarbons generated from the enclosing organic-rich (TOC ranges from 0.55 to 6.77wt

  5. Engineering Sedimentary Geothermal Resources for Large-Scale Dispatchable Renewable Electricity

    NASA Astrophysics Data System (ADS)

    Bielicki, Jeffrey; Buscheck, Thomas; Chen, Mingjie; Sun, Yunwei; Hao, Yue; Saar, Martin; Randolph, Jimmy

    2014-05-01

    Mitigating climate change requires substantial penetration of renewable energy and economically viable options for CO2 capture and storage (CCS). We present an approach using CO2 and N2 in sedimentary basin geothermal resources that (1) generates baseload and dispatchable power, (2) efficiently stores large amounts of energy, and (3) enables seasonal storage of solar energy, all which (5) increase the value of CO2 and render CCS commercially viable. Unlike the variability of solar and wind resources, geothermal heat is a constant source of renewable energy. Using CO2 as a supplemental geothermal working fluid, in addition to brine, reduces the parasitic load necessary to recirculate fluids. Adding N2 is beneficial because it is cheaper, will not react with materials and subsurface formations, and enables bulk energy storage. The high coefficients of thermal expansion of CO2 and N2 (a) augment reservoir pressure, (b) generate artesian flow at the production wells, and (c) produce self-convecting thermosiphons that directly convert reservoir heat to mechanical energy for fluid recirculation. Stored pressure drives fluid production and responds faster than conventional brine-based geothermal systems. Our design uses concentric rings of horizontal wells to create a hydraulic divide that stores supplemental fluids and pressure. Production and injection wells are controlled to schedule power delivery and time-shift the parasitic power necessary to separate N2 from air and compress it for injection. The parasitic load can be scheduled during minimum power demand or when there is excess electricity from wind or solar. Net power output can nearly equal gross power output during peak demand, and energy storage is almost 100% efficient because it is achieved by the time-shift. Further, per-well production rates can take advantage of the large productivity of horizontal wells, with greater leveraging of well costs, which often constitute a major portion of capital costs for

  6. Norian-Rhaetian sedimentary evolution of the Slovenian Basin (eastern Southern Alps)

    NASA Astrophysics Data System (ADS)

    Gale, L.; Šmuc, A.; Kolar-Jurkovšek, T.; Skaberne, D.; Celarc, B.; Čar, J.; Rožič, B.

    2012-04-01

    The Slovenian Basin represents a Mesozoic deep water sedimentary environment, during the Triassic situated on the southern passive continental margin of the Neotethys (Meliata) Ocean (cf. Schmid et al., 2008). The Norian-Rhaetian sedimentary evolution of the Slovenian Basin is reconstructed on the basis of five sections located in different parts of the Tolmin Nappe (Eastern Southern Alps, western Slovenia). The correlation of sections is based on conodont data and facies analysis. The Norian-Rhaetian interval is in the basin represented by the "Bača dolomite" (bedded dolostone with chert) and the Slatnik Formation (hemipelagic and allodapic limestones), while the bordering reef-rimmed carbonate platforms in inner areas record peritidal deposition (Main Dolomite, Dachstein Limestone). The transition from claystone and marly limestone dominated "Amphiclina beds" to the bedded "Bača dolomite" took place at the Carnian-Norian boundary. The change in facies can be attributed to the eustatic rise of sea-level and the subsequent retreat of terrigenous input. Intensive basin-wide slumping took place during the Early Norian and marks a short period of tectonic activity. Slump breccias are followed by bedded dolostones. An increase in terrigenous input in pyrite-enriched thin-bedded dolostones indicates a relative sea-level fall (cf. Haas, 2002) at the Early-Middle Norian boundary. The Middle-Late Norian sedimentation is dominated by bedded dolostones. The microfacies analysis of scarce non-dolomitized horizons indicates hemipelagic deposition and sedimentation from distal turbidites, with material derived from adjacent platform. An interval of slump breccias suggests that another tectonic pulse took place during the Middle Norian. The Late Norian in the northern part of the Tolmin Nappe already belongs to the Slatnik Formation, which spans the rest of the Triassic, while in other parts of the Basin the "Bača dolomite" continues up to the Triassic-Jurassic boundary. The

  7. Fluid migration in sedimentary basins - a case study from the Central European Basin

    NASA Astrophysics Data System (ADS)

    Duschl, Florian; van den Kerkhof, Alfons; Leiss, Bernd; Sosa, Graciela; Wiegand, Bettina; Vollbrecht, Axel; Sauter, Martin

    2014-05-01

    Core samples from the cap rock of an Upper Permian dolomitic limestone from the Zechstein formation (Stassfurt carbonate sequence, Ca2) in the Central European Basin were studied for a better understanding of the tectonic control on fluid migration during the burial and uplift of CO2-rich gas reservoirs. Petrographical investigations were carried out by means of optical transmission and cathodoluminescence microscopy. A heating-freezing stage was applied for fluid inclusion analysis; gas compositions were measured by Laser-Raman spectroscopy. The study focuses on the quantification of paleo pressures, temperatures and compositions of diagenetic fluids trapped as inclusions in dolomite, anhydrite, calcite, and fluorite, as well as in postdiagenetic fluorite in mineralized fractures. Limestone matrix mainly consists of early diagenetic, euhedral dolomite with few hydrocarbon-bearing inclusions. Offset veins originating from fine-grained inclusion-free anhydrite nodules consist of coarse-grained recrystallized anhydrite containing primary aqueous CaCl2-rich inclusions. Late calcite cement fills remnant pores between the dolomite rhombs and contains H2O-NaCl-CaCl2 fluid inclusions. Subsequently, the dolomitic limestones were affected by pressure solution due to burial, followed by basin inversion (uplift) starting in Upper Cretaceous. Pressure solution generated carbonate rich fluids, which resulted in dolomite and calcite veinlets. Simultaneously, a first clearly zoned and brown coloured generation of fluorite (I) accumulated in nodules together with sulfides and organic matter. This fluorite (I) contains mostly H2O-NaCl-CaCl2 fluid inclusions with relatively high salinity (17.8 wt% NaCl, 8.9 wt% CaCl2). Colourless fluorite (II) is the latest observable (post-) diagenetic mineral phase filling veinlets in dolomitic limestone that crosscut pressure solution features. Fluorite (II) replaces fluorite (I) within the nodules as well. Carbonic inclusions together with CH4

  8. Fluvial-aeolian interactions in sediment routing and sedimentary signal buffering: an example from the Indus Basin and Thar Desert

    USGS Publications Warehouse

    East, Amy E.; Clift, Peter D.; Carter, Andrew; Alizai, Anwar; VanLaningham, Sam

    2015-01-01

    Sediment production and its subsequent preservation in the marine stratigraphic record offshore of large rivers are linked by complex sediment-transfer systems. To interpret the stratigraphic record it is critical to understand how environmental signals transfer from sedimentary source regions to depositional sinks, and in particular to understand the role of buffering in obscuring climatic or tectonic signals. In dryland regions, signal buffering can include sediment cycling through linked fluvial and eolian systems. We investigate sediment-routing connectivity between the Indus River and the Thar Desert, where fluvial and eolian systems exchanged sediment over large spatial scales (hundreds of kilometers). Summer monsoon winds recycle sediment from the lower Indus River and delta northeastward, i.e., downwind and upstream, into the desert. Far-field eolian recycling of Indus sediment is important enough to control sediment provenance at the downwind end of the desert substantially, although the proportion of Indus sediment of various ages varies regionally within the desert; dune sands in the northwestern Thar Desert resemble the Late Holocene–Recent Indus delta, requiring short transport and reworking times. On smaller spatial scales (1–10 m) along fluvial channels in the northern Thar Desert, there is also stratigraphic evidence of fluvial and eolian sediment reworking from local rivers. In terms of sediment volume, we estimate that the Thar Desert could be a more substantial sedimentary store than all other known buffer regions in the Indus basin combined. Thus, since the mid-Holocene, when the desert expanded as the summer monsoon rainfall decreased, fluvial-eolian recycling has been an important but little recognized process buffering sediment flux to the ocean. Similar fluvial-eolian connectivity likely also affects sediment routing and signal transfer in other dryland regions globally.

  9. Tectonic and Sedimentary Response of the Huangshan Basin to Paleo-Pacific Subduction undernearth Southeast China

    NASA Astrophysics Data System (ADS)

    Xu, X.; Tang, S.; Lin, S.

    2015-12-01

    The subduction of the Paleo-Pacific Plate predominated the Late Mesozoic tectonic evolution of southeast China. This process is well documented by Jurassic-Cretaceous deposition and structural deformation. Zircon U-Pb ages of volcano-sedimentary rocks and fault-slip data of brittle faults were investigated in the Huangshan Basin. Detrital zircon U-Pb ages show that the provenances of the Huangshan Basin changed during Late Jurassic to Early Cretaceous. The source region of Early and Middle Jurassic sediments is mainly the Wuyishan domain to the southeast. But the Early Cretaceous clastic rocks are derived from the Jiangnan domain to the north. The inversions of fault-slip data show that paleostress fields also changed during Late Jurassic to Early Cretaceous. The strike-slip regime with nearly E-W compression and N-S extension predominated in the late Middle Jurassic whereas intense NW-SE-striking extensional one during Early Cretaceous. Moreover, geochemistry and zircon U-Pb ages of Late Jurassic (156~152 Ma) and Early Cretaceous (~130 Ma) felsic volcanic rocks in the Huangshan Basin also argue for a tectonic event occurred during Late Jurassic to Early Cretaceous. Above results imply that the tectonic background of southeast China changed from the initial subduction of the Paleo-Pacific plate during the Early and Middle Jurassic into subsequence back-arc extension in the Early Cretaceous. The paleostress field then changed into the strike-slip regime with N-S compression and E-W extension during late Early Cretaceous, which is caused by the collision between the Philippine and South China blocks. And after that, a weak and short-lived N-S extension was replaced by the strike-slip regime with NW-SE compression and NE-SW extension. Meanwhile, the South China continental margin also changed from an Andean-type to a Western Pacific-type plate boundary in early Late Cretaceous.

  10. Framework for the assessment of interaction between CO2 geological storage and other sedimentary basin resources.

    PubMed

    Michael, K; Whittaker, S; Varma, S; Bekele, E; Langhi, L; Hodgkinson, J; Harris, B

    2016-02-01

    Sedimentary basins around the world considered suitable for carbon storage usually contain other natural resources such as petroleum, coal, geothermal energy and groundwater. Storing carbon dioxide in geological formations in the basins adds to the competition for access to the subsurface and the use of pore space where other resource-based industries also operate. Managing potential impacts that industrial-scale injection of carbon dioxide may have on other resource development must be focused to prevent potential conflicts and enhance synergies where possible. Such a sustainable coexistence of various resource developments can be accomplished by implementing a Framework for Basin Resource Management strategy (FBRM). The FBRM strategy utilizes the concept of an Area of Review (AOR) for guiding development and regulation of CO2 geological storage projects and for assessing their potential impact on other resources. The AOR is determined by the expected physical distribution of the CO2 plume in the subsurface and the modelled extent of reservoir pressure increase resulting from the injection of the CO2. This information is used to define the region to be characterised and monitored for a CO2 injection project. The geological characterisation and risk- and performance-based monitoring will be most comprehensive within the region of the reservoir containing the carbon dioxide plume and should consider geological features and wells continuously above the plume through to its surface projection; this region defines where increases in reservoir pressure will be greatest and where potential for unplanned migration of carbon dioxide is highest. Beyond the expanse of the carbon dioxide plume, geological characterisation and monitoring should focus only on identified features that could be a potential migration conduit for either formation water or carbon dioxide.

  11. 1-D/3-D geologic model of the Western Canada Sedimentary Basin

    USGS Publications Warehouse

    Higley, D.K.; Henry, M.; Roberts, L.N.R.; Steinshouer, D.W.

    2005-01-01

    The 3-D geologic model of the Western Canada Sedimentary Basin comprises 18 stacked intervals from the base of the Devonian Woodbend Group and age equivalent formations to ground surface; it includes an estimated thickness of eroded sediments based on 1-D burial history reconstructions for 33 wells across the study area. Each interval for the construction of the 3-D model was chosen on the basis of whether it is primarily composed of petroleum system elements of reservoir, hydrocarbon source, seal, overburden, or underburden strata, as well as the quality and areal distribution of well and other data. Preliminary results of the modeling support the following interpretations. Long-distance migration of hydrocarbons east of the Rocky Mountains is indicated by oil and gas accumulations in areas within which source rocks are thermally immature for oil and (or) gas. Petroleum systems in the basin are segmented by the northeast-trending Sweetgrass Arch; hydrocarbons west of the arch were from source rocks lying near or beneath the Rocky Mountains, whereas oil and gas east of the arch were sourced from the Williston Basin. Hydrocarbon generation and migration are primarily due to increased burial associated with the Laramide Orogeny. Hydrocarbon sources and migration were also influenced by the Lower Cretaceous sub-Mannville unconformity. In the Peace River Arch area of northern Alberta, Jurassic and older formations exhibit high-angle truncations against the unconformity. Potential Paleozoic though Mesozoic hydrocarbon source rocks are in contact with overlying Mannville Group reservoir facies. In contrast, in Saskatchewan and southern Alberta the contacts are parallel to sub-parallel, with the result that hydrocarbon source rocks are separated from the Mannville Group by seal-forming strata within the Jurassic. Vertical and lateral movement of hydrocarbons along the faults in the Rocky Mountains deformed belt probably also resulted in mixing of oil and gas from numerous

  12. Cenozoic uplift on the West Greenland margin: active sedimentary basins in quiet Archean terranes.

    NASA Astrophysics Data System (ADS)

    Jess, Scott; Stephenson, Randell; Brown, Roderick

    2016-04-01

    The North Atlantic is believed by some authors to have experienced tectonically induced uplift within the Cenozoic. Examination of evidence, onshore and offshore, has been interpreted to imply the presence of kilometre scale uplift across the margins of the Barents Sea, North Sea, Baffin Bay and Greenland Sea. Development of topography on the West Greenland margin (Baffin Bay), in particular, has been subject to much discussion and dispute. A series of low temperature thermochronological (AFT and AHe) studies onshore and interpretation of seismic architecture offshore have suggested uplift of the entire margin totalling ~3km. However, challenges to this work and recent analysis on the opposing margin (Baffin Island) have raised questions about the validity of this interpretation. The present work reviews and remodels the thermochronological data from onshore West Greenland with the aim of re-evaluating our understanding of the margin's history. New concepts within the discipline, such as effect of radiation damage on Helium diffusivity, contemporary modelling approaches and denudational mapping are all utilised to investigate alternative interpretations to this margins complex post rift evolution. In contrast to earlier studies our new approach indicates slow protracted cooling across much of the region; however, reworked sedimentary samples taken from the Cretaceous Nuussuaq Basin display periods of rapid reheating and cooling. These new models suggest the Nuussuaq Basin experienced a tectonically active Cenozoic, while the surrounding Archean basement remained quiet. Faults located within the basin appear to have been reactivated during the Palaeocene and Eocene, a period of well-documented inversion events throughout the North Atlantic, and may have resulted in subaerial kilometre scale uplift. This interpretation of the margin's evolution has wider implications for the treatment of low temperature thermochronological data and the geological history of the North

  13. Anisotropic mechanical behaviour of sedimentary basins inferred by advanced radar interferometry above gas storage fields

    NASA Astrophysics Data System (ADS)

    Teatini, P.; Gambolati, G.; Ferretti, A.

    2010-12-01

    Natural gas is commonly stored underground in depleted oil and gas fields to provide safe storage capacity and deliverability to market areas where production is limited, or to take advantage of seasonal price swings. In response to summer gas injection and winter gas withdrawal the reservoir expands and contracts with the overlying land that moves accordingly. Depending on the field burial depth, a few kilometres of the upper lithosphere are subject to local three-dimensional deformations with the related cyclic motion of the ground surface being both vertical and horizontal. Advanced Persistent Scatterer Interferometry (PSI) data, obtained by combining ascending and descending RADARSAT-1 images acquired from 2003 to 2008 above gas storage fields located in the sedimentary basin of the Po river plain, Italy, provide reliable measurement of these seasonal vertical ups and downs as well as horizontal displacements to and from the injection/withdrawal wells. Combination of the land surface movements together with an accurate reconstruction of the subsurface geology made available by three-dimensional seismic surveys and long-time records of fluid pore pressure within the 1000-1500 m deep reservoirs has allowed for the development of an accurate 3D poro-mechanical finite-element model of the gas injection/removal occurrence. Model calibration based on the observed cyclic motions, which are on the range of 10-15 mm and 5-10 mm in the vertical and horizontal west-east directions, respectively, helps characterize the nonlinear hysteretic geomechanical properties of the basin. First, using a basin-scale relationship between the oedometric rock compressibility cM in virgin loading conditions versus the effective intergranular stress derived from previous experimental studies, the modeling results show that the ratio s between loading and unloading-reloading cM is about 4, consistent with in-situ expansions measured by the radioactive marker technique in similar reservoirs

  14. Late Paleozoic paleofjord in the southernmost Parana Basin (Brazil): Geomorphology and sedimentary fill

    NASA Astrophysics Data System (ADS)

    Tedesco, Julia; Cagliari, Joice; Coitinho, Julia dos Reis; da Cunha Lopes, Ricardo; Lavina, Ernesto Luiz Correa

    2016-09-01

    In the southernmost part of the Parana Basin, records of the late Paleozoic glaciation occur in a discontinuous form preserved in paleovalley systems excavated in the crystalline basement. This paper addresses one of these paleovalleys, the Mariana Pimentel, which extends over 60 km with NW-SE valley direction and a constant width of 2.5 km. With the objective of demonstrating that the paleovalley worked as a fjord during the glaciation period, its origin as well as sedimentary fill and morphology were analyzed. The paleovalley morphology was obtained through electrical resistivity (electrical sounding and lateral mapping) and mathematical modeling in four transverse sections. The morphology of the paleovalley documented by the U-shape, steady width, and high depth reaching up to 400 m are typical features of modern glacial valleys. The sedimentary facies that fill the base of the paleovalley, such as rhythmites and dropstones with thickness up to 70 m and diamictites with faceted pebbles (up to 5 m thick) are signs of its glacial origin. During the glaciation period, the paleovalley had a connection to the epicontinental sea located to the northwest, extended toward Namibia, and was excavated by glaciers from the highlands of this region. Thus, the evidence attests that the Mariana Pimentel paleovalley was a fjord during the late Paleozoic glaciation. The duration of the late Paleozoic glaciation (which is longer than the Quaternary glaciation), the apatite fission track that suggests erosion up to 4 km thick in the study area, and the lack of preserved hanging valleys in the Mariana Pimentel indicate that the paleovalley once featured a higher dimension. Furthermore, the existence of paleofjords excavated in the border of the basement corroborates the idea of small ice centers controlled by topography during the late Paleozoic glaciation.

  15. The first deep heat flow determination in crystalline basement rocks beneath the Western Canadian Sedimentary Basin

    NASA Astrophysics Data System (ADS)

    Majorowicz, Jacek; Chan, Judith; Crowell, James; Gosnold, Will; Heaman, Larry M.; Kück, Jochem; Nieuwenhuis, Greg; Schmitt, Douglas R.; Unsworth, Martyn; Walsh, Nathaniel; Weides, Simon

    2014-05-01

    Heat flow (Q) determined from bottom-hole temperatures measured in oil and gas wells in Alberta show a large scatter with values ranging from 40 to 90 mW m-2. Only two precise measurements of heat flow were previously reported in Alberta, and were made more than half a century ago. These were made in wells located near Edmonton, Alberta, and penetrated the upper kilometre of clastic sedimentary rocks yielding heat flows values of 61 and 67 mW m-2 (Garland & Lennox). Here, we report a new precise heat flow determination from a 2363-m deep well drilled into basement granite rocks just west of Fort McMurray, Alberta (the Hunt Well). Temperature logs acquired in 2010-2011 show a significant increase in the thermal gradient in the granite due to palaeoclimatic effects. In the case of the Hunt Well, heat flow at depths >2200 m is beyond the influence of the glacial-interglacial surface temperatures. Thermal conductivity and temperature measurements in the Hunt Well have shown that the heat flow below 2.2 km is 51 mW m-2 (±3 mW m-2), thermal conductivity measured by the divided bar method under bottom of the well in situ like condition is 2.5 W m-1 K-1, and 2.7 W m-1 K-1 in ambient conditions), and the geothermal gradient was measured as 20.4 mK m-1. The palaeoclimatic effect causes an underestimate of heat flow derived from measurements collected at depths shallower than 2200 m, meaning other heat flow estimates calculated from basin measurements have likely been underestimated. Heat production (A) was calculated from spectral gamma recorded in the Hunt Well granites to a depth of 1880 m and give an average A of 3.4 and 2.9 μW m-3 for the whole depth range of granites down to 2263 m, based on both gamma and spectral logs. This high A explains the relatively high heat flow measured within the Precambrian basement intersected by the Hunt Well; the Taltson Magmatic Zone. Heat flow and related heat generation from the Hunt Well fits the heat flow-heat generation

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

    SciTech Connect

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

    1995-05-01

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

  17. Anatomy of mass transport deposits in the Dead Sea: sedimentary processes in an active tectonic hypersaline basin

    NASA Astrophysics Data System (ADS)

    Waldmann, Nicolas; Hadzhiivanova, Elitsa; Neugebauer, Ina; Brauer, Achim; Schwab, Markus; Frank, Ute; Dulski, Peter

    2014-05-01

    Continental archives such as interplate endorheic lacustrine sedimentary basins provide an excellent source of data for studying regional climate, seismicity and environmental changes through time. Such is the case for the sediments that were deposited in the Dead Sea basin, a tectonically active pull-apart structure along the Dead Sea fault (DSF). This elongated basin is characterized by steep slopes and a deep and flat basin-floor, which are constantly shaped by seismicity and climate. In this study, we present initial results on the sedimentology and internal structure of mass transport deposits in the Pleistocene Dead Sea. The database used for this study consists of a long core retrieved at ~300 m water depth in the deepest part of the Dead Sea as part of an international scientific effort under the auspice of the ICDP. Micro-facies analysis coupled by elemental scanning (µXRF), granulometry and petrophysical measurements (magnetic susceptibility) have been carried out on selected intervals in order to decipher and identify the source-to-sink processes and controlling mechanisms behind the formation of mass transport deposits. The findings of this study allowed defining and characterizing the mass transport deposits into separate sedimentary facies according to the lake level and limnological conditions. Investigating sediments from the deep Dead Sea basin allowed better understanding and deciphering the depositional processes in relation with the tectonic forces shaping this basin.

  18. Development and hydrocarbon potential of Mesozoic sedimentary basins around margins of North Atlantic

    SciTech Connect

    Masson, D.G.; Miles, P.R.

    1986-06-01

    The Late Triassic-Early Jurassic rift basins of Iberia, offshore eastern Canada, and the continental shelf of western Europe are fragments of a formerly coherent northeast-trending rift system that probably formed as a result of tensional stress between Europe, Africa, and North America. The separation of Europe, North America, and Iberia was preceded by a Late Jurassic-Early Cretaceous rifting phase that is clearly distinct from the earlier Mesozoic rifting episode and was little influenced by it. The two periods of rifting are separated by a Middle Jurassic relatively tectonically quiet period. The distribution of hydrocarbon finds within the rift basin suggests that the best prospects are in areas where the two rifting episodes are superimposed. Lack of mature source rocks in the later Mesozoic rift basins and an unfavorable temporal relationship between hydrocarbon generation and tectonic activity in the early Mesozoic basins are proposed as explanations for the apparently poor hydrocarbon prospectivity of large areas of the Mesozoic basins.

  19. Large Sanjiang basin groups outside of the Songliao Basin Meso-Senozoic Tectonic-sediment evolution and hydrocarbon accumulation

    NASA Astrophysics Data System (ADS)

    Zheng, M.; Wu, X.

    2015-12-01

    The basis geological problem is still the bottleneck of the exploration work of the lager Sanjiang basin groups. In general terms, the problems are including the prototype basins and basin forming mechanism of two aspects. In this paper, using the field geological survey and investigation, logging data analysis, seismic data interpretation technical means large Sanjiang basin groups and basin forming mechanism of the prototype are discussed. Main draw the following conclusions: 1. Sanjiang region group-level formation can be completely contrasted. 2. Tension faults, compressive faults, shear structure composition and structure combination of four kinds of compound fracture are mainly developed In the study area. The direction of their distribution can be divided into SN, EW, NNE, NEE, NNW, NWW to other groups of fracture. 3. Large Sanjiang basin has the SN and the EW two main directions of tectonic evolution. Cenozoic basins in Sanjiang region in group formation located the two tectonic domains of ancient Paleo-Asian Ocean and the Pacific Interchange. 4. Large Sanjiang basin has experienced in the late Mesozoic tectonic evolution of two-stage and nine times. The first stage, developmental stage basement, they are ① Since the Mesozoic era and before the Jurassic; ② Early Jurassic period; The second stage, cap stage of development, they are ③ Late Jurassic depression developmental stages of compression; ④ Early Cretaceous rifting stage; ⑤ depression in mid-Early Cretaceous period; ⑥ tensile Early Cretaceous rifting stage; ⑦ inversion of Late Cretaceous tectonic compression stage; ⑧ Paleogene - Neogene; ⑨ After recently Ji Baoquan Sedimentary Ridge. 5. Large Sanjiang basin group is actually a residual basin structure, and Can be divided into left - superimposed (Founder, Tangyuan depression, Hulin Basin), residual - inherited type (Sanjiang basin), residual - reformed (Jixi, Boli, Hegang basin). there are two developed depression and the mechanism

  20. Integrated workflow for characterizing and modeling a mixed sedimentary system: The Ilerdian Alveolina Limestone Formation (Graus-Tremp Basin, Spain)

    NASA Astrophysics Data System (ADS)

    Hamon, Youri; Deschamps, Remy; Joseph, Philippe; Doligez, Brigitte; Schmitz, Julien; Lerat, Olivier

    2016-09-01

    This paper proposes an advanced stochastic workflow to jointly model sedimentary facies and diagenesis. The formation of interest is the Early Eocene Alveolina Limestone Formation, which outcrops in the Serraduy area (Graus-Tremp Basin, NE Spain). Ten sedimentary lithotypes representing facies or facies associations of a mixed siliciclastic-carbonate ramp system were identified within the succession. A 3D model describing the depositional architecture is also proposed. The results from the diagenetic study evidenced the occurrence of several successive calcite cements, which were grouped into five diagenetic imprints for modeling. These imprints were then quantified to ease their integration into numerical models. The following step consisted in building a 3D gridded model with seven different modeling units. They were populated using a bi-plurigaussian simulation approach that reproduced both the sedimentary organization and the observed diagenetic imprint distributions. Last, the simulation results were validated referring to paleogeographic and diagenetic conceptual maps.

  1. Anisotropic P-wave velocity analysis and seismic imaging in onshore Kutch sedimentary basin of India

    NASA Astrophysics Data System (ADS)

    Behera, Laxmidhar; Khare, Prakash; Sarkar, Dipankar

    2011-08-01

    The long-offset P-wave seismic reflection data has observable non-hyperbolic moveout, which depend on two parameters such as normal moveout velocity ( Vnmo) and the anisotropy parameter( η). Anisotropy (e.g., directional dependence of velocity at a fixed spatial location in a medium) plays an important role in seismic imaging. It is difficult to know the presence of anisotropy in the subsurface geological formations only from P-wave seismic data and special analysis is required for this. The presence of anisotropy causes two major distortions of moveout in P-wave seismic reflection data. First, in contrast to isotropic media, normal-moveout (NMO) velocity differs from the vertical velocity; and the second is substantial increase of deviations in hyperbolic moveout in an anisotropic layer. Hence, with the help of conventional velocity analysis based on short-spread moveout (stacking) velocities do not provide enough information to determine the true vertical velocity in a transversely isotropic media with vertical symmetry axis (VTI media). Therefore, it is essential to estimate the single anisotropic parameter ( η) from the long-offset P-wave seismic data. It has been demonstrated here as a case study with long-offset P-wave seismic data acquired in onshore Kutch sedimentary basin of western India that suitable velocity analysis using Vnmo and η can improve the stacking image obtained from conventional velocity analysis.

  2. Microbial methane formation in deep aquifers of a coal-bearing sedimentary basin, Germany

    PubMed Central

    Gründger, Friederike; Jiménez, Núria; Thielemann, Thomas; Straaten, Nontje; Lüders, Tillmann; Richnow, Hans-Hermann; Krüger, Martin

    2015-01-01

    Coal-bearing sediments are major reservoirs of organic matter potentially available for methanogenic subsurface microbial communities. In this study the specific microbial community inside lignite-bearing sedimentary basin in Germany and its contribution to methanogenic hydrocarbon degradation processes was investigated. The stable isotope signature of methane measured in groundwater and coal-rich sediment samples indicated methanogenic activity. Analysis of 16S rRNA gene sequences showed the presence of methanogenic Archaea, predominantly belonging to the orders Methanosarcinales and Methanomicrobiales, capable of acetoclastic or hydrogenotrophic methanogenesis. Furthermore, we identified fermenting, sulfate-, nitrate-, and metal-reducing, or acetogenic Bacteria clustering within the phyla Proteobacteria, complemented by members of the classes Actinobacteria, and Clostridia. The indigenous microbial communities found in the groundwater as well as in the coal-rich sediments are able to degrade coal-derived organic components and to produce methane as the final product. Lignite-bearing sediments may be an important nutrient and energy source influencing larger compartments via groundwater transport. PMID:25852663

  3. Spatial and seasonal contrasts of sedimentary organic matter in floodplain lakes of the central Amazon basin

    NASA Astrophysics Data System (ADS)

    Sobrinho, R. L.; Bernardes, M. C.; Abril, G.; Kim, J.-H.; Zell, C. I.; Mortillaro, J.-M.; Meziane, T.; Moreira-Turcq, P.; Sinninghe Damsté, J. S.

    2016-01-01

    In this study, we investigated the seasonal and spatial pattern of sedimentary organic matter (SOM) in five floodplain lakes of the central Amazon basin (Cabaliana, Janauaca, Canaçari, Mirituba and Curuai) which have different morphologies, hydrodynamics and vegetation coverages. Surface sediments were collected in four hydrological seasons: low water (LW), rising water (RW), high water (HW) and falling water (FW) in 2009 and 2010. We investigated commonly used bulk geochemical tracers such as the C : N ratio and the stable isotopic composition of organic carbon (δ13Corg). These results were compared with lignin phenol parameters as an indicator of vascular plant detritus and branched glycerol dialkyl glycerol tetraethers (brGDGTs) to trace the input of soil organic matter (OM) from land to the aquatic settings. We also applied the crenarchaeol as an indicator of aquatic (rivers and lakes) OM. Our data showed that during the RW and FW seasons, the surface sediments were enriched in lignin and brGDGTs in comparison to other seasons. Our study also indicated that floodplain lake sediments primarily consisted of allochthonous, C3 plant-derived OM. However, a downstream increase in C4 macrophyte-derived OM contribution was observed along the gradient of increasing open waters - i.e., from upstream to downstream. Accordingly, we attribute the temporal and spatial difference in SOM composition to the hydrological dynamics between the floodplain lakes and the surrounding flooded forests.

  4. A reaction kinetic approach to the temperature-time history of sedimentary basins

    NASA Astrophysics Data System (ADS)

    Sajgó, Cs.; Lefler, J.

    Three biological marker reactions have been studied in order to determine the temperature — time history of a sedimentary sequence. Two of these reactions are configurational isomerization reactions, at C-20 in a C29-sterane and at C-22 in C31 and C32 hopane hydrocarbons. In the third reaction two C29 C-ring monoaromatic steroid hydrocarbons convert to a C28 triaromatic one. The progress of these reactions is different because of their different rate constants. Based on temperature and age data obtained from field measurements and on concentration measurements of reactants and products in core samples of a Pannonian borehole, we calculated the rate parameters: pre-exponential factors, enthalpies and entropies of activation. It is obvious, that at least two different reactions are necessary to characterize the maturity of any system. The aromatization seems to be a rather complicated reaction, and we believe its use to be premature. Fortunately, two isomerizations work well and are suitable for elucidation of thermal history in different basins if the rate constants are universally valid.

  5. Age and paleoenvironmental reconstruction of partially remagnetized lacustrine sedimentary rocks (Oligocene Aktoprak basin, central Anatolia, Turkey)

    NASA Astrophysics Data System (ADS)

    Meijers, Maud J. M.; Strauss, Becky E.; Özkaptan, Murat; Feinberg, Joshua M.; Mulch, Andreas; Whitney, Donna L.; Kaymakçı, Nuretdin

    2016-03-01

    The age and paleoenvironmental record of lacustrine deposits in the Aktoprak basin of south-central Turkey provides information about the evolution of topography, including the timing of development of an orographic rain shadow caused by uplift of the mountain ranges fringing the Central Anatolian Plateau. New magnetostratigraphy-based age estimates, in combination with existing biostratigraphic ages, suggest that the partially remagnetized Kurtulmuş Tepe section of the basin is Chattian (Upper Oligocene). The mean carbon and oxygen stable isotope ratios (δ18O= 24.6 ± 2.0 ‰, δ13C= -4.9 ± 1.1‰) are largely constant through the section and indicative of a subtropical, open freshwater lake. These isotopic values are also similar to those of the Chattian Mut basin to the south, on the Mediterranean side of the modern orographic barrier (Tauride Mountains), and indicate absence of an orographic barrier during Late Oligocene basin deposition. Post-depositional partial remagnetization occurred after tilting of the basin sequence and was mineralogically controlled, affecting grey, carbonate-rich rocks (average %CaCO3= 82), whereas interlayered pink carbonate-poor rocks (average %CaCO3= 38) carry a primary, pretilt magnetization. The pink rocks are rich in clay minerals that may have reduced the permeability of these rocks that carry a primary magnetization, concentrating basinal fluid flow in the carbonate-rich grey layers and leading to the removal and reprecipitation of magnetic minerals. The normal and reverse polarities recorded by the remagnetized rocks suggest that remagnetization occurred over a protracted period of time.

  6. Stagnant lid convection and the thermal subsidence of sedimentary basins with reference to Michigan

    NASA Astrophysics Data System (ADS)

    Sleep, Norman H.

    2009-12-01

    The thermal subsidence of basins formed above thick continental lithosphere differs from that of young passive margin basins and of young oceanic crust in that stagnant lid convection supplies significant heat flow from the asthenosphere. The lithosphere eventually approaches thermal equilibrium where the convective heat added to its base balances the heat lost by conduction to the surface. This paper presents a simple parameterization that quantifies these effects for modeling basin subsidence. The convective heat flow scales with the current lithosphere thickness squared while the conductive heat flow scales inversely to current lithospheric thickness. The predicted thermal subsidence rate scales to the difference between the conductive and convective heat flows and wanes gradually over hundreds of millions of years. The formalism can be modified to represent thermal subsidence where plume material has ponded within a catchment of locally thinned lithosphere. The base of the plume material forms a stable stratification that suppresses convective heat flow from below while heat continues to conduct to the surface by conduction. The predicted initial thermal subsidence rate scales with the large difference between conductive and zero convective heat flow. It is thus much greater than beneath lithosphere underlain by ordinary asthenosphere for a given amount of total eventual thermal subsidence. The paper compares thermal subsidence predictions from the models with and without plumes with sedimentation data from the Michigan basin. Observed initial Late Cambrian through Lower Devonian sedimentation in the Michigan basin is rapid as expected from the plume model, but the Ordovician sedimentation rate is slower than before and after. It is conceivable that this irregularity in the sedimentation curve is associated with low eustatic sea level and sediment-starved conditions at the basin center in the Ordovician and Early Silurian periods, as opposed to irregular

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

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

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

  8. Accretionary prism-forearc interactions as reflected in the sedimentary fill of southern Thrace Basin (Lemnos Island, NE Greece)

    NASA Astrophysics Data System (ADS)

    Maravelis, A. G.; Pantopoulos, G.; Tserolas, P.; Zelilidis, A.

    2015-06-01

    Architecture of the well-exposed ancient forearc basin successions of northeast Aegean Sea, Greece, provides useful insights into the interplay between arc magmatism, accretionary prism exhumation, and sedimentary deposition in forearc basins. The upper Eocene-lower Oligocene basin fill of the southern Thrace forearc basin reflects the active influence of the uplifted accretionary prism. Deep-marine sediments predominate the basin fill that eventually shoals upwards into shallow-marine sediments. This trend is related to tectonically driven uplift and compression. Field, stratigraphic, sedimentological, petrographic, geochemical, and provenance data on the lower Oligocene shallow-marine deposits revealed the accretionary prism (i.e. Pindic Cordillera or Biga Peninsula) as the major contributor of sediments into the forearc region. Field investigations in these shallow-marine deposits revealed the occurrence of conglomerates with: (1) mafic and ultramafic igneous rock clasts, (2) low-grade metamorphic rock fragments, and (3) sedimentary rocks. The absence of felsic volcanic fragments rules out influence of a felsic source rock. Geochemical analysis indicates that the studied rocks were accumulated in an active tectonic setting with a sediment source of mainly mafic composition, and palaeodispersal analysis revealed a NE-NNE palaeocurrent trend, towards the Rhodopian magmatic arc. Thus, these combined provenance results make the accretionary prism the most suitable candidate for the detritus forming these shallow-marine deposits.

  9. Seismic stratigraphy of sedimentary cover in the southern Amerasia Basin between 140E and 170W

    NASA Astrophysics Data System (ADS)

    Poselov, V.; Butsenko, V.; Kaminskiy, V.; Kireev, A.; Grikurov, G.

    2013-12-01

    Seismic reflection data (MCS) acquired by Russian expeditions in 2007, 2009, 2011 and 2012 are correlated with earlier Polarstern (AWI-91090) and US (78AR_808) lines calibrated by drilling on the Lomonosov Ridge (LR) and in the Chukchi Sea (ACEX hole and POPCORN well, respectively). In the absence of direct intersections between those and Russian lines, the correlation is based on analysis of wave fields. Main seismic horizons and their intervening units are traced throughout the entire study area. The uppermost unconformity in both holes is related to pre-Miocene depositional hiatus at the base of essentially hemipelagic unit. Specific wave characteristics of both the unconformity and overlying sediments are persistently recorded on seismic lines. Hemipelagic drape is typically relatively thin (few hundred meters) but may thicken to ~1,500-2,000 m in some deepwater basins. Another major depositional hiatus spanning ~20 Ma is interpreted in the ACEX hole between the lowermost drilled Campanian and Upper Paleocene units. On seismic records it is recognized as post-Campanian unconformity (pCU) traced along the length of the near-Siberia segment of LR and in deep shelf/margin sedimentary basins of the East Siberian and western Chukchi Seas. Farther east pCU correlates with Mid-Brookian unconformity (MBU) separating the Lower and Upper Brookian terrigenous sequences. In Popcorn well the Upper Brookian is about 1,300 m thick; on the Russian margin a comparable thickness of equivalent Upper Paleocene-Eocene units sandwiched between pCU and pre-Miocene unconformity is observed only in structural lows. Older cover units on the Russian East Arctic margin are not sampled by drilling. Among them only one displays particular wave field features clearly comparable to those observed in the carbonate-dominated Carboniferous-Permian Lisburne Group (LG) of the US Chukchi Sea. This marker sequence is confidently recognized on seismic sections in the North Chukchi Trough (NCT) and

  10. Current channelling and three-dimensional effects detected from magnetotelluric data from a sedimentary basin in Sierras Pampeanas, Argentina

    NASA Astrophysics Data System (ADS)

    Pomposiello, C.; Osella, A.; Favetto, A.; Sainato, C.; Martinelli, P.; Aprea, C.

    1998-11-01

    Aquifer-bearing intermontane sedimentary basins of the Sierras Pampeanas in the northwest of Argentina are in general very deep and narrow and contain economically important deposits of Tertiary sediments. This paper presents the results of a study to characterize the sedimentary basin bounded to the west by Sierra de Famatina and to the east by Sierra de Velasco, where an electromagnetic sensing technique, the magnetotelluric (MT) method, was applied. 12 MT sites were deployed along a 30 km E-W transect. Some of the data collected were used to derive a 2-D resistivity model of the basin. The model shows a subsurface trough with a thick (approximately 8 km) sedimentary sequence above it. Anomalous behaviour of the E-W electric-field component (Ey) was detected in the period range 1-100 s, where the amplitude of this component was below the instrumental noise level. The cause of this anomaly is not known, but it might be due to the presence of an embedded conducting body between 8 and 10 km, which would give rise to N-S current channelling.

  11. Verification of the Adjoint-tomography Inversion of the Small-scale Surface Sedimentary Structure: The Case of the Mygdonian Basin, Greece

    NASA Astrophysics Data System (ADS)

    Kubina, Filip; Moczo, Peter; Kristek, Jozef

    2015-04-01

    We apply the full-waveform inversion using the adjoint method to the Mygdonian basin, Greece, a local surface sedimentary basin. A canonical perturbation of the 2D EUROSEISTEST model is considered as a true (target) model and numerically simulated seismograms for the model as recorded seismograms. The 2D EUROSEISTEST model itself is taken as a starting model for inversion. The point DC sources are located relatively deeply beneath the basin and receivers are at the free surface. Due to the configuration and relatively strong velocity gradient in sediments, direct waves propagate almost vertically and almost in the same way for all sources. As a consequence, the coverage of the basin by the source-receiver configuration cannot be considered favourable. Resolution of kernels based on direct arrivals in the vertical direction is therefore very weak. It is necessary to use the entire seismograms. The complete wavefield in the basin is complicated and seismic motion considerably prolonged due to multiple reflections resulting in generation and propagation of local surface waves. Consequently, the corresponding kernel is very complicated. Large velocity contrasts and configuration of receivers imply kernel concentration in low-velocity layers near receivers. The spatial complexity of a kernel strongly depends on a seismogram section used for evaluating misfit and can be simplified by smoothing and spatially dependent normalization. Without simplification the inversion may be not converging properly. On the other hand, the simplification reduces the resolution of the inversion. We investigate a balance between a reasonable level of kernel simplification and inversion resolution in order to find practical criteria for the inversion of the local surface sedimentary structures.

  12. A review of stratigraphy and sedimentary environments of the Karoo Basin of South Africa

    NASA Astrophysics Data System (ADS)

    Smith, R. M. H.

    The Karoo Supergroup covers almost two thirds of the present land surface of southern Africa. Its strata record an almost continuous sequence of continental sedimentation that began in the Permo-Carboniferous (280 Ma) and terminated in the early Jurassic 100 million years later. The glacio-marine to terrestrial sequence accumulated in a variety of tectonically controlled depositories under progressively more arid climatic conditions. Numerous vertebrate fossils are preserved in these rocks, including fish, amphibians, primitive aquatic reptiles, primitive land reptiles, more advanced mammal-like reptiles, dinosaurs and even the earliest mammals. Palaeoenvironmental analysis of the major stratigraphic units of the Karoo sequence demonstrates the effects of more localised tectonic basins in influencing depositional style. These are superimposed on a basinwide trend of progressive aridification attributed to the gradual northward migration of southwestern Gondwanaland out of polar climes and accentuated by the meteoric drying effect of the surrounding land masses. Combined with progressive climatic drying was a gradual shrinking of the basin brought about by the northward migration of the subducting palaeo-Pacific margin to the south. Following deposition of the Cape Supergroup in the pre-Karoo basin there was a period of uplift and erosion. At the same time the southern part of Gondwana migrated over the South Pole resulting in a major ice-sheet over the early Karoo basin and surrounding highlands. Glacial sedimentation in both upland valley and shelf depositories resulted in the basal Karoo Dwyka Formation. After glaciation, an extensive shallow sea remained over the gently subsiding shelf fed by large volumes of meltwater. Black clays and muds accumulated under relatively cool climatic conditions (Lower Ecca) with perhaps a warmer "interglacial" during which the distinctive Mesosaurus-bearing, carbonaceous shales of the Whitehill Formation were deposited

  13. Seismic stratigraphy of sedimentary cover in Amerasian Basin based on the results of Russian High Arctic expeditions

    NASA Astrophysics Data System (ADS)

    Poselov, Viktor; Kireev, Artem; Smirnov, Oleg; Butsenko, Viktor; Zholondz, Sergey; Savin, Vasily

    2016-04-01

    Massive amount of multichannel seismic (MCS) data were obtained by Russian High Arct ic expeditions "Arctica-2011", "Acrtica-2012" and "Arctica-2014". More than 40 MCS lines are located in the Amerasian basin and help to substantiate the seismic stratigraphy model of its sedimentary cover. The proposed seismic stratigraphy model was successively determined for the Cenozoic and pre-Cenozoic parts of the sedimentary section and was based on correlation of the Russian MCS data and seismic data documented by boreholes. Cenozoic part of the sedimentary cover is based on correlation of the Russian MCS data and AWI91090 section calibrated by ACEX-2004 boreholes on the Lomonosov Ridge. Two major unconformities are traced. The upper regional unconformity (RU) is associated with a major pre-Miocene hiatus. Another major hiatus is recorded in the borehole section between the Campanian and the Upper Paleocene units. It is recognized as the post-Campanian unconformity (pCU) in the seismic sections. Formation of the regional unconformities is associated with a fundamental change in depositional environment. Formation of RU was initiated by opening of the Fram Strait gateway at the Paleogene/Neogene boundary. Post-Campanian unconformity is linked with the initial stage of the Eurasian Basin opening between the Cretaceous and the Paleogene. Cenozoic sedimentary units are continuously traced from the East-Siberian and Chukchi sea shelves across the transit zone to the Amerasian basin. Paleogene unit (between pCU and RU) is formed under the neritic depositional environment and it is characterized by an extremely small thickness on the Lomonosov Ridge (less than 200 m), on the Mendeleev Rise and in the Podvodnikov Basin (not more than 300-400 m). Neogene unit (above RU) consists of hemipelagic deposits and occupies the essential part of thickness of the Cenozoic section in Podvodnikov and Makarov Basins. Interval velocities in the Paleogene unit vary within 2.8-3.2 km/s, in the

  14. Sedimentary Rocks and Dunes

    NASA Technical Reports Server (NTRS)

    2004-01-01

    25 November 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows buttes composed of light-toned, sedimentary rock exposed by erosion within a crater occurring immediately west of Schiaparelli Basin near 4.0oS, 347.9oW. Surrounding these buttes is a field of dark sand dunes and lighter-toned, very large windblown ripples. The sedimentary rocks might indicate that the crater interior was once the site of a lake. The image covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the lower left.

  15. Seasonal and spatial contrasts of sedimentary organic carbon in floodplain lakes of the central Amazon basin.

    NASA Astrophysics Data System (ADS)

    Sobrinho, Rodrigo; Kim, Jung-Hyun; Abril, Gwenaël; Zell, Claudia; Moreira-Turcq, Patricia; Mortillaro, Jean-Michel; Meziane, Tarik; Damsté, Jaap; Bernardes, Marcelo

    2014-05-01

    Three-quarters of the area of flooded land in the world are temporary wetlands (Downing, 2009), which play a significant role in the global carbon cycle(Einsele et al., 2001; Cole et al., 2007; Battin et al., 2009; Abril et al., 2013). Previous studies of the Amazonian floodplain lakes (várzeas), one important compartment of wetlands, showed that the sedimentation of organic carbon (OC) in the floodplain lakes is strongly linked to the periodical floods and to the biogeography from upstream to downstream(Victoria et al., 1992; Martinelli et al., 2003). However, the main sources of sedimentary OC remain uncertain. Hence, the study of the sources of OC buried in floodplain lake sediments can enhance our understanding of the carbon balance of the Amazon ecosystems. In this study, we investigated the seasonal and spatial pattern of sedimentary organic matter in five floodplain lakes of the central Amazon basin (Cabaliana, Janauaca, Canaçari, Miratuba, and Curuai) which have different morphologies, hydrodynamics and vegetation coverage. Surface sediments were collected in four hydrological seasons: low water (LW), rising water (RW), high water (HW) and falling water (FW) in 2009 and 2010. We investigated commonly used bulk geochemical tracers such as C:N ratio and stable isotopic composition of organic carbon (δ13COC). These results were compared with lignin-phenol parameters as an indicator of vascular plant detritus (Hedges and Ertel, 1982) and branched glycerol dialkyl glycerol tetraethers (brGDGTs) to trace the soil OC from land to the aquatic settings (Hopmans et al., 2004). Our data showed that during the RW and FW seasons, the concentration of lignin and brGDGTs were higher in comparison to other seasons. Our study also indicated that floodplain lake sediments primarily consisted of a mixture of C3 plant detritus and soil OC. However, a downstream increase in C4 plant-derived OC contribution was observed along the gradient of increasingly open waters, i

  16. Geochemical and detrital mode evidence for two sources of Early Proterozoic sedimentary rocks from the Tonto Basin Supergroup, central Arizona

    USGS Publications Warehouse

    Condie, K.C.; Noll, P.D.; Conway, C.M.

    1992-01-01

    The Tonto Basin Supergroup includes up to 6.5 km of Early Proterozoic sedimentary and volcanic rocks that were deposited in a relatively short period of time at about 1.7 Ga in central Arizona. Moderate correlations of rare earth elements (REE) and Ti with Al2O3 and REE distributions in detrital sediments of this supergroup suggest that these elements are contained chiefly in clay-mica and/or zircon fractions. REE distributions, including negative Eu anomalies in most Tonto Basin sediments, are similar to those in Phanerozoic shales. Weak to moderate correlations of Fe, Sc, Ni, and Co to Al2O3 also suggest a clay-mica control of these elements. Detrital modes and geochemical characteristics of sediments indicate two dominant sources for sedimentary rocks of the Tonto Basin Supergroup: a granitoid source and a volcanic source. The granitoid source was important during deposition of the upper part of the succession (the Mazatzal Group) as shown by increases in K2O, Al2O3, and Th in pelites with stratigraphic height, and increases in Zr and Hf and decreases in Eu/Eu*, Cr, and Ni in in pelites of the Maverick Shale. Sediment provenance characteristics and paleocurrent indicators are consistent with deposition of the supergroup in a continental-margin back-arc basin. The granitoid sediment source appears to have been the North American craton on the north, and the volcanic source a more local source from an arc on the south. ?? 1992.

  17. Geothermal energy from deep sedimentary basins: The Valley of Mexico (Central Mexico)

    NASA Astrophysics Data System (ADS)

    Lenhardt, Nils; Götz, Annette E.

    2015-04-01

    The geothermal potential of the Valley of Mexico has not been addressed in the past, although volcaniclastic settings in other parts of the world contain promising target reservoir formations. A first assessment of the geothermal potential of the Valley of Mexico is based on thermophysical data gained from outcrop analogues, covering all lithofacies types, and evaluation of groundwater temperature and heat flow values from literature. Furthermore, the volumetric approach of Muffler and Cataldi (1978) leads to a first estimation of ca. 4000 TWh (14.4 EJ) of power generation from Neogene volcanic rocks within the Valley of Mexico. Comparison with data from other sedimentary basins where deep geothermal reservoirs are identified shows the high potential of the Valley of Mexico for future geothermal reservoir utilization. The mainly low permeable lithotypes may be operated as stimulated systems, depending on the fracture porosity in the deeper subsurface. In some areas also auto-convective thermal water circulation might be expected and direct heat use without artificial stimulation becomes reasonable. Thermophysical properties of tuffs and siliciclastic rocks qualify them as promising target horizons (Lenhardt and Götz, 2015). The here presented data serve to identify exploration areas and are valuable attributes for reservoir modelling, contributing to (1) a reliable reservoir prognosis, (2) the decision of potential reservoir stimulation, and (3) the planning of long-term efficient reservoir utilization. References Lenhardt, N., Götz, A.E., 2015. Geothermal reservoir potential of volcaniclastic settings: The Valley of Mexico, Central Mexico. Renewable Energy. [in press] Muffler, P., Cataldi, R., 1978. Methods for regional assessment of geothermal resources. Geothermics, 7, 53-89.

  18. A Framework to Estimate CO2 Leakage associated with Geological Storage in Mature Sedimentary Basins

    NASA Astrophysics Data System (ADS)

    Celia, M. A.; Bachu, S.; Gasda, S.

    2002-12-01

    Geological storage of carbon dioxide requires careful risk analysis to avoid unintended consequences associated with the subsurface injection. Most negative consequences of subsurface injection are associated with leakage of the injected CO2 out of the geological formation into which it is injected. Such leakage may occur through natural geological features, including fractures and faults, or it may occur through human-created pathways such as existing wells. Possible leakage of CO2 through existing wells appears to be especially important in mature sedimentary basins that have been explored intensively and exploited for hydrocarbon production. In the Alberta Basin of western Canada, more than 300,000 oil and gas wells have been drilled, while in the state of Texas in the United States, more than 1,500,000 wells have been drilled. Many of these wells have been abandoned, and the information available to describe their current state is highly variable and sometimes nonexistent. Because these wells represent possible direct conduits from the injection zone to the land surface, a comprehensive assessment of leakage potential associated with these wells needs to be pursued. Analysis of leakage potential associated with existing wells must combine a data mining component with a multi-level modeling effort to assess leakage potential in a probabilistic framework. Information available for existing wells must be categorized and analyzed, and general leakage characteristics associated with wells of varying properties must be quantified. One example of a realistic target formation is the Viking Formation in Alberta, which is overlain by a thick shale layer and contains hydrocarbon in some locations. The existence of hydrocarbon in the formation indicates that the overlying shale layer is an effective barrier to flow, and therefore this is a good candidate formation for CO2 storage. However, the formation and its cap rock are punctured by approximately 180,000 wells, with

  19. Provenance change from the Middle to Late Triassic of the southwestern Sichuan basin, Southwest China: Constraints from the sedimentary record and its tectonic significance

    NASA Astrophysics Data System (ADS)

    Zhu, Min; Chen, Hanlin; Zhou, Jing; Yang, Shufeng

    2017-03-01

    The formation of the Sanjiang and Qinling orogens caused by closure of Paleo-Tethys Ocean along the western and northern margins of the Yangtze block during the early Mesozoic created a unique basin-mountain system. Petrology, geochemistry, geochronology, sedimentary facies and paleocurrent data are integrated in order to investigate the changing provenance of Middle-Late Triassic successions from the southwestern Sichuan region, SW China. The detrital compositions from the Middle Triassic successions indicate low mature sediments of mafic and intermediate rocks origin, which derivation mainly from recycled orogenic and secondarily from the Emeishan Large Igneous Province (ELIP). The detrital zircon U-Pb age distribution pattern of the Middle Triassic sandstone samples exhibits four major age Groups at 257 Ma, 650-500 Ma, 880-710 Ma, and 1000-900 Ma. Combined with the geochemical characteristics, an interior Yangtze block source including the Khamdian uplift and ELIP is suggested. The Late Triassic sedimentary rocks yield seven U-Pb age Groups at 245-210 Ma, 290-260 Ma, 460-410 Ma, 650 Ma, 880-710 Ma, 1900-1600 Ma, and 2600-2400 Ma, which are consistent with the data reported from the Sichuan basin, Songpan Ganzi basin and the southern Yidun terrane, and are partly similar to those of the south Qinling orogen, Jiangnan Xuefeng thrust belt. In contrast to the Middle Triassic successions, the sandstone composition modals and whole-rock geochemistry of the Late Triassic samples denote mature deposits and of intermediate and acid rocks origin. Therefore, during the Late Triassic, the southwestern Sichuan basin received materials from the Songpan Ganzi folded belt and Yidun arc complex dominantly, and from the Qinling orogen and Jiangnan Xuefeng thrust belt subsidiarily. The Sanjiang orogen and the Songpan Ganzi folded belt should have controlled the formation of the southwestern Sichuan basin, while the development of the Qinling orogen and the western Jiangnan

  20. Extensional deformation of the Guadalquivir Basin: rate of WSW-ward tectonic displacement from Upper Tortonian sedimentary rocks

    NASA Astrophysics Data System (ADS)

    Roldán, Francisco J.; Azañón, Jose Miguel; Rodríguez-Fernández, Jose; María Mateos, Rosa

    2016-04-01

    The Guadalquivir Basin (Upper Tortonian-Quaternary sedimentary infilling) has been considered the foreland basin of the Betic Orogen built up during its collision with the Sudiberian margin. The basin is currently restricted to its westernmost sector, in the Cadiz Gulf, because the Neogene-Quaternary uplift of the Betic Cordillera has produced the emersion of their central and eastern parts. The upper Tortonian chronostratigraphic unit is the oldest one and it was indistinctly deposited on the South Iberian paleomargin and the External units from the Betic Cordillera. However, these rocks are undeformed on the Sudiberian paleomargin while they are deeply affected by brittle deformation on the External Betic Zone. Outcrops of Upper Tortonian sedimentary rocks on External Betic Zone are severely fragmented showing allocthonous characters with regard to those located on the Sudiberian paleomargin. This post- Upper Tortonian deformation is not well known in the External Zones of the Cordillera where the most prominent feature is the ubiquity of a highly deformed tecto-sedimentary unit outcropping at the basement of the Guadalquivir sedimentary infilling. This tecto-sedimentary unit belongs to the Mass Wasting Extensional Complex (Rodríguez-Fernández, 2014) formed during the collision and westward migration of the Internal Zone of the Betic Cordillera (15-8,5 Ma). In the present work, we show an ensemble of tectonic, geophysical and cartographic data in order to characterize the post-Upper Tortonian deformation. For this, seismic reflection profiles have been interpreted with the help of hidrocarbon boreholes to define the thickness of the Upper Tortonian sedimentary sequence. All these data provide an estimation of the geometrical and kinematic characteristics of the extensional faults, direction of movement and rate of displacement of these rocks during Messinian/Pliocene times. References Rodríguez-Fernández, J., Roldan, F. J., J.M. Azañón y Garcia-Cortes, A

  1. Tectonic and sedimentary evolution of the Ili Basin (northern Tien Shan, Kazakhstan)

    NASA Astrophysics Data System (ADS)

    Kley, J.; Voigt, T.; Seib, N.; Kober, M.

    2010-12-01

    The Tien Shan active intraplate orogen of Central Asia exhibits strong along-strike variations in structure. Its northern front in southeastern Kazakhstan is characterized by a fragmented array of anticlinal basement highs whose wavelengths range from c. 5 to 30 km. Range-bounding faults are mostly E- to ENE-trending thrust or reverse faults and SE-trending dextral strike-slip faults. Faults of large displacement (more than several tens of meters) are conspicuously absent. The synclinal lows between the basement highs preserve Cenozoic strata of Oligocene to Quaternary age, probably deposited in a once continuous basin (the Ili Basin) and recording the entire history of Tien Shan uplift. Very gentle, long-wavelength folds affect the Cenozoic strata. As far as visible, the basement is always folded conformably. The basin fill starts in the middle Oligocene (mammal fossils; Indricotherium horizon). The facies of these oldest deposits is characterized by fluvial deposits of a large river system and varying flood-plain deposits with intense soil formation (calcretes and gypsisols). Transport directions and quartz content of the sediments suggest they were not sourced from the nearby mountain ranges present today. The fluvial succession is followed by late Oligocene to early Miocene lake deposits which reflect the transition from an evaporitic lake/playa system to freshwater lacustrine conditions. The Oligocene to Early Miocene deposits are limited to a small area in the core of the Aktau anticline and show no relationship to the sediment succession overlying the basement in the uplifts surrounding the Aktau mountains in the north and west. There, alluvial and fluvial deposits of middle Miocene(?) age rest on deeply weathered paleosurfaces. Transport is mainly to the south. Changes in colour, grain size and ratio of channel to interchannel deposits probably reflect climatic changes. Rapid facies and thickness-changes allow the reconstruction of several alluvial fans

  2. Tectono-sedimentary evolution of an extensional basin revealed by a combined photo-geological and field-mapping approach. The Montefalco Basin (Northern Apennines, Italy)

    NASA Astrophysics Data System (ADS)

    Bucci, Francesco; Mirabella, Francesco; Santangelo, Michele; Cardinali, Mauro; Guzzetti, Fausto

    2016-04-01

    Active extensional basins are important since their sedimentary infills and bounding tectonic structures provide: i) sinks with preservation potential for sedimentary and fossil records of past changes in climate and sediment/water supply, ii) information on the growth, activity, decay and death of normal faults, iii) vast economic reserves of hydrocarbons, water and minerals. Unfortunately, quaternary extensional basins, especially if located in humid and temperate climate environments, are often characterized by extensively cultivated areas, homogeneous terrains and quite flat morphologies. Furthermore, they commonly host human settlements, together with roads, economic and industrial infrastructures, with a consequent limited availability of good outcrops. Such a limitation can (often severely) hamper an adequate mapping of the sedimentary infill. Therefore alternative methodological approaches (such as aerial photographs interpretation, API) are needed to integrate heterogeneous and incomplete datasets. This contribution presents an updated photo-geological map of a Quaternary extensional basin in Central Italy, the Montefalco Basin. This basin developed in a continental environment characterized by clayey-sandy lacustrine and fluvial sequences (late Pliocene - early Pleistocene) underlying more recent coarse grained deposits related to alluvial fan environment (early-to-late Pleistocene) and younger palustrine deposits (late Pleistocene). Since the late Pleistocene, regional uplift and local tectonics led to the end of deposition in the Montefalco basin, which experienced a diffuse incision and the modification of the drainage network, in response to the W-to-E migration of active faulting and tectonic subsidence. The new photo-geological map represents an important improvement compared to the existing data, since it provides unprecedented and spatially distributed information on the geometry of the continental deposits and on the tectonic structures affecting

  3. A regional view of urban sedimentary basins in Northern California based on oil industry compressional-wave velocity and density logs

    USGS Publications Warehouse

    Brocher, T.M.

    2005-01-01

    Compressional-wave (sonic) and density logs from 119 oil test wells provide knowledge of the physical properties and impedance contrasts within urban sedimentary basins in northern California, which is needed to better understand basin amplification. These wire-line logs provide estimates of sonic velocities and densities for primarily Upper Cretaceous to Pliocene clastic rocks between 0.1 - and 5.6-km depth to an average depth of 1.8 km. Regional differences in the sonic velocities and densities in these basins largely 1reflect variations in the lithology, depth of burial, porosity, and grain size of the strata, but not necessarily formation age. For example, Miocene basin filling strata west of the Calaveras Fault exhibit higher sonic velocities and densities than older but finer-grained and/or higher-porosity rocks of the Upper Cretaceous Great Valley Sequence. As another example, hard Eocene sandstones west of the San Andreas Fault have much higher impedances than Eocene strata, mainly higher-porosity sandstones and shales, located to the east of this fault, and approach those expected for Franciscan Complex basement rocks. Basement penetrations define large impedence contrasts at the sediment/basement contact along the margins of several basins, where Quaternary, Pliocene, and even Miocene deposits directly overlie Franciscan or Salinian basement rocks at depths as much as 1.7 km. In contrast, in the deepest, geographic centers of the basins, such logs exhibit only a modest impedance contrast at the sediment/basement contact at depths exceeding 2 km. Prominent (up to 1 km/sec) and thick (up to several hundred meters) velocity and density reversals in the logs refute the common assumption that velocities and densities increase monotonically with depth.

  4. Schiaparelli's Sedimentary Rocks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    9 October 2004 Schiaparelli Basin is a large, 470 kilometer (292 miles) impact crater located east of Sinus Meridiani. The basin might once have been the site of a large lake--that is, if the sedimentary rocks exposed on its northwestern floor were deposited in water. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a 1.5 meter per pixel (5 ft per pixel) view of some of the light-toned, finely-bedded sedimentary rocks in northwestern Schiaparelli. The image is located near 1.0oS, 346.0oW, and covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the left.

  5. Thickness detection of sedimentary basin by P-to-S-phases of earthquake recordings at Ibaraki-ken, Japan

    NASA Astrophysics Data System (ADS)

    Hao, K.; Fujiwara, H.

    2007-12-01

    The Kanto sedimentary basin has very complicated geological formations with various sedimentary layers. The thickness of sedimentary basins varies irregularly from zeros to over several thousand meters down to the pre- Neogene bedrock. Therefore, the understanding the thickness is the fundamental in order to study the seismic ground motions. The vertical seismic profile (VSP) method may give a high-resolution seismic image at a borehole in both of P and S wave information. However, VSP is only limited to a few areas since it is too costly to be widely used. A dozen of deep-wells down to 2000 meters with VSP in the Kanto area have been drilled over past 15 years by NIED. In order to extend the high-quality VSP results farthest, we utilize these VSP data to obtain regression functions for sedimentary depth against the travel time difference of direct P and the direct S waves. On the other hands, the travel time difference between the direct P and the converted PS waves may be detected from P-to-S converted phases by means of all-pass function deconvolved from Receiver Functions (APRF) (Izumi et.al., 1990, Satoh, 2005, Hao, et.al., 2005, 2006). Comparing the classic receiver function for detection of interfaces with abrupt velocity changes in the earth crust, this APRF method can identify P-to-S phase in the near- surface interfaces much clearly, even for a high frequency of 10Hz. We use APRF with the VSP regression functions to estimate the thickness of sedimentary basin beneath each ground motion station. The objective area in this paper is whole of Prefecture Ibaraki-ken, which is located at north-east part of Kanto basin. The northern and northwestern of Ibaraki-ken are mountain areas, and Mt. Tsukuba and Lake kasumigaura are located in the center. A total of 112 strong motion stations, in which 84 stations from Sk-net, 19 K-net, and 14 KiK-net, have been targeted to study the underground structure beneath each station. Over 3000x3 records have been visually

  6. Constraints on the history and topography of the Northeastern Sierra Nevada from a Neogene sedimentary basin in the Reno-Verdi area, Western Nevada

    USGS Publications Warehouse

    Trexler, James; Cashman, Patricia; Cosca, Michael

    2012-01-01

    Neogene (Miocene–Pliocene) sedimentary rocks of the northeastern Sierra Nevada were deposited in small basins that formed in response to volcanic and tectonic activity along the eastern margin of the Sierra. These strata record an early phase (ca. 11–10 Ma) of extension and rapid sedimentation of boulder conglomerates and debrites deposited on alluvial fans, followed by fluvio-lacustrine sedimentation and nearby volcanic arc activity but tectonic quiescence, until ~ 2.6 Ma. The fossil record in these rocks documents a warmer, wetter climate featuring large mammals and lacking the Sierran orographic rain shadow that dominates climate today on the eastern edge of the Sierra. This record of a general lack of paleo-relief across the eastern margin of the Sierra Nevada is consistent with evidence presented elsewhere that there was not a significant topographic barrier between the Pacific Ocean and the interior of the continent east of the Sierra before ~ 2.6 Ma. However, these sediments do not record an integrated drainage system either to the east into the Great Basin like the modern Truckee River, or to the west across the Sierra like the ancestral Feather and Yuba rivers. The Neogene Reno-Verdi basin was one of several, scattered endorheic (i.e., internally drained) basins occupying this part of the Cascade intra-arc and back-arc area.

  7. EGS in sedimentary basins: sensitivity of early-flowback tracer signals to induced-fracture parameters

    NASA Astrophysics Data System (ADS)

    Karmakar, Shyamal; Ghergut, Julia; Sauter, Martin

    2015-04-01

    -effective aperture, in a water fracture (WF), or - fracture thickness and porosity, for a gel-proppant fracture (GPF). We find that parameter determination from SW early signals can significantly be improved by concomitantly using a number of solute tracers with different transport and retardation behaviour. We considered tracers of different sorptivity to proppant coatings, and to matrix rock surfaces, for GPF, as well as contrasting-diffusivity or -sorptivity tracers, for WF. An advantage of this SW approach is that it requires only small chaser volumes (few times the fracture volume), not relying on advective penetration into the rock matrix. Thus, selected tracer species are to be injected during the very last stage of the fracturing process, when fracture sizes and thus target parameters are supposed to attain more or less stable values. We illustrate the application of these tracer test design principles using hydro- and lithostratigraphy data from the Geothermal Research Platform at Groß Schönebeck [4], targeting a multi-layer reservoir (sedimentary and crystalline formations in 4-5 km depth) in the NE-German Sedimentary Basin. Acknowledgments: This work benefited from long-term support from Baker Hughes (Celle) and from the Lower-Saxonian Science and Culture Ministry (MWK Niedersachsen) within the applied research project gebo (Geothermal Energy and High-Performance Drilling, 2009-2014). The first author gratefully acknowledges continued financial support from the DAAD (German Academic Exchange Service) to pursuing Ph. D. work. References: [1] http://www.sciencedirect.com/science/article/pii/S1876610214017391 [2] http://www.geothermal-energy.org/cpdb/record_detail.php?id=7215 [3] http://www.geothermal-energy.org/cpdb/record_detail.php?id=19034 [4] http://www.gfz-potsdam.de/en/scientific-services/laboratories/gross-schoenebeck/

  8. 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.

  9. Sedimentary budgets of the Tanzania coastal basin and implications for uplift history of the East African rift system

    NASA Astrophysics Data System (ADS)

    Said, Aymen; Moder, Christoph; Clark, Stuart; Abdelmalak, Mohamed Mansour

    2015-11-01

    Data from 23 wells were used to quantify the sedimentary budgets in the Tanzania coastal basin in order to unravel the uplift chronology of the sourcing area located in the East African Rift System. We quantified the siliciclastic sedimentary volumes preserved in the Tanzania coastal basin corrected for compaction and in situ (e.g., carbonates) production. We found that the drainage areas, which supplied sediments to this basin, were eroded in four episodes: (1) during the middle Jurassic, (2) during the Campanian-Palaeocene, (3) during the middle Eocene and (4) during the Miocene. Three of these high erosion and sedimentation periods are more likely related to uplift events in the East African Rift System and earlier rift shoulders and plume uplifts. Indeed, rapid cooling in the rift system and high denudation rates in the sediment source area are coeval with these recorded pulses. However, the middle Eocene pulse was synchronous with a fall in the sea level, a climatic change and slow cooling of the rift flanks and thus seems more likely due to climatic and eustatic variations. We show that the rift shoulders of the East African rift system have inherited their present relief from at least three epeirogenic uplift pulses of middle Jurassic, Campanian-Palaeocene, and Miocene ages.

  10. On the formation of ultra-thick sedimentary basins on rifted margins: a comparison of the Scotian and Labrador margins

    NASA Astrophysics Data System (ADS)

    Louden, K.; Funck, T.

    2003-12-01

    Sedimentary basins that form on rifted continental margins exhibit a great variety of shapes and sizes. In particular, the total sediment thickness can vary significantly and in certain sub-basins can approach 15-20 km. The deeper structure of these ultra-thick basins is typically not well resolved by seismic reflection profiles due to poor penetration within the thickest parts of the basin. Wide-angle seismic reflection/refraction profiles can help resolve these deeper features. We compare two such sub-basins that occur on the eastern Canadian margins, where reflection and refraction profiles are able to define the complete sedimentary and crustal structures: the Sable sub-basin on the northeast Nova Scotian margin and the Hopedale sub-basin on the central Labrador margin. We compare the development of these basins by converting the sediment refraction velocities to density and back-stripping assuming local isostasy. Although these basins formed during completely different episodes of rifting on different types of continental crust, we find a surprising similarity in the characteristics of crustal thinning across each margin, especially for the lower crust. Initial thinning of the crust by 50-60% occurs within 50 km followed by more gradual thinning over the subsequent 100 km. This leaves a tongue of lower continental crust extending 150 km seaward of the unstretched continental crust. This outer region becomes the location of the thickest initial sediment deposition, followed by up-building and out-building of the shelf. The local form of this deposition differs between the two margins: with much larger syn- and immediately post-rift sediments on the Scotian margin and thicker recent deposition on the Labrador margin, probably controlled by the local availability of sediment fill. Comparison with previous models of rifting based on borehole observations for the Scotia margin compare well with the overall width of the rifting (150 km), but our results suggest more

  11. Sedimentary Record of the Back-Arc Basins of South-Central Mexico: an Evolution from Extensional Basin to Carbonate Platform.

    NASA Astrophysics Data System (ADS)

    Sierra-Rojas, M. I.; Molina-Garza, R. S.; Lawton, T. F.

    2015-12-01

    The Lower Cretaceous depositional systems of southwestern Oaxaquia, in south-central Mexico, were controlled by tectonic processes related to the instauration of a continental arc and the accretion of the Guerrero arc to mainland Mexico. The Atzompa Formation refers to a succession of conglomerate, sandstone, siltstone, and limestone that crop out in southwestern Mexico with Early Cretaceous fauna and detrital zircon maximum depositional ages. The sedimentary record shows a transition from early fluvial/alluvial to shallow marine depositional environments. The first stage corresponds to juvenile fluvial/alluvial setting followed by a deep lacustrine depositional environment, suggesting the early stages of an extensional basin. The second stage is characterized by anabranched deposits of axial fluvial systems flowing to the NE-SE, showing deposition during a period of rapid subsidence. The third and final stage is made of tidal deposits followed, in turn, by abrupt marine flooding of the basin and development of a Barremian-Aptian carbonate ramp. We interpret the Tentzo basin as a response to crustal extension in a back-arc setting, with high rates of sedimentation in the early stages of the basin (3-4 mm/m.y), slower rates during the development of starved fluvial to tidal systems and carbonate ramps, and at the top of the Atzompa Formation an abrupt deepening of the basin due to flexural subsidence related to terrane docking and attendant thrusting to the west. These events were recorded in the back-arc region of a continental convergent margin (Zicapa arc) where syn-sedimentary magmatism is indicated by Early Cretaceous detrital and volcanic clasts from alluvial fan facies west of the basin. Finally, and as a response to the accretion of the Guerrero superterrane to Oaxaquia during the Aptian, a carbonate platform facing toward the Gulf of Mexico was established in central to eastern Oaxaquia.

  12. Application of Response Surface based Calibration and Sensitivity Analysis methods for Regional Hydrogeological Modelling in the Western Canada Sedimentary Basin

    NASA Astrophysics Data System (ADS)

    Singh, A.; Palombi, D.; Huff, G. F.

    2014-12-01

    A regional scale study of groundwater flow dynamics was undertaken in the Western Canada Sedimentary Basin (WCSB), comprising parts of Alberta, Saskatchewan and British Columbia. The objective of the study is to investigate basin-scale hydrogeology in WCSB and to establish boundary conditions for future local-scale groundwater management models. Earlier work in the Alberta basin has acknowledged the fact that in addition to topography controlled conditions, a substantial part of the basin exhibits sub-hydrostatic regimes. The basin-scale model (approx. 420,000 km2) includes Upper Cretaceous aquifers to Recent age sediments which collectively attain maximum thicknesses of >2600 m. Regional aquifer units considered for the numerical model are Quaternary sediments, and the sedimentary rocks of the Paskapoo, Scollard, Horseshoe Canyon formations and the Belly River Group. Regional aquitards delineated include the Battle and Bear Paw formations. The study area is bound to the west by the Brazeau-Waptiti thrust belt and to the south by the Canada-USA international border. The boundary to the north and east is delineated by the maximum extent of the Wapiti and Belly River groups and Judith River Formation. USGS MODFLOW was implemented for numerical simulation. The steady state numerical model was calibrated using a Response Surface based (Radial Basis Functions) optimization method. The calibration targets (~2000) were comprised of drill stem tests for deeper units and static water levels for shallower units. Petrophysical analyses of cores averaged K values from analyses of aquifer test results,and literature values were used to provide initial values and calibration ranges for hydraulic properties. Results indicate predominance of topography driven, local- to intermediate-scale flow systems in all hydrostratigraphic units with recharge of these units occurring in the foothills of the Rocky Mountains. The Battle aquitard, where present, acts to retard regional flow

  13. Diffusive anisotropy in low-permeability Ordovician sedimentary rocks from the Michigan Basin in southwest Ontario.

    PubMed

    Xiang, Y; Al, T; Scott, L; Loomer, D

    2013-12-01

    Diffusive anisotropy was investigated using samples from Upper Ordovician shale and argillaceous limestone from the Michigan Basin of southwest Ontario, Canada. Effective diffusion coefficients (De) were determined for iodide (I(-)) and tritiated water (HTO) tracers on paired cm-scale subsamples oriented normal (NB) and parallel to bedding (PB) prepared from preserved drill cores within one year from the date of drilling. For samples with porosity >3%, an X-ray radiography method was used with I(-) tracer for determination of De and porosity accessible to I(-) ions. A through-diffusion method with I(-) and HTO tracers was used for most siltstone and limestone samples with low-porosity (<3%). The De values range from 7.0×10(-13) to 7.7×10(-12) m(2)·s(-1) for shale, 2.1×10(-13) to 1.3×10(-12) m(2)·s(-1) for limestone, and 5.3×10(-14) to 5.6×10(-13) m(2)·s(-1) for siltstone and limestone interbeds within the Georgian Bay Formation shale. The sample-scale anisotropy ratios (De-PB:De-NB) for De values obtained using the I(-) tracer are 0.9 to 4.9, and the anisotropy ratios for the HTO tracer are in the range of 1.1 to 7.0. The influence of porosity distribution on diffusive anisotropy has been investigated using one-dimensional spatially-resolved profiles of I(-)-accessible porosity (shale only) and the use of AgNO3 for fixation of I(-) tracer in the pores, allowing for SEM visualization of I(-)-accessible pore networks. The porosity profiles at the sample scale display greatest variability in the direction normal to bedding which likely reflects sedimentary depositional processes. The SEM imaging suggests that diffusion pathways are preferentially oriented parallel to bedding in the shale and that diffusion occurs dominantly within the argillaceous component of the limestone. However, the fine clay-filled intergranular voids in the dolomitic domains of the limestone are also accessible for diffusive transport.

  14. Seepage carbonate mounds in Cenozoic sedimentary sequences from the Las Minas Basin, SE Spain

    NASA Astrophysics Data System (ADS)

    Pozo, M.; Calvo, J. P.; Scopelliti, G.; González-Acebrón, L.

    2016-04-01

    A number of carbonate mounds composed of indurate, strongly folded and/or brecciated calcite and dolomite beds occur interstratified in Cenozoic sedimentary sequences from the Las Minas Basin. Part of the fabric of the rock forming the carbonate mounds is composed of laminated to banded dolostone similar to the host rock but showing contrasted lithification. Moreover, the carbonate deposits of the mounds display aggrading neomorphism of dolomite, partial replacement of dolomite by calcite, calcite cementation, and extensive silicification, locally resulting in box-work fabric. Eight main lithofacies were distinguished in the carbonate mound deposits. In some lithofacies, chert is present as both microcrystalline to fibro-radial quartz and opal, the latter occurring mainly as cement whereas the former replace the carbonate and infill voids. Yet one of the carbonate mounds shows distinctive petrography and geochemical features thus suggesting a distinctive growth pattern. The carbon isotope compositions of calcite from the mound samples range from - 11.56 to - 5.15 δ‰ whilst dolomite is depleted in 13C, with values of - 12.38 to 3.02 δ‰. Oxygen isotopic compositions vary from - 9.42 to - 4.64 δ‰ for calcite and between - 6.68 and 8.19 δ‰ for dolomite. Carbonate in the mounds shows significant enrichment in Co, Cr, Ni and Pb content, especially in the strongly deformed (F-2-2 lithofacies) and brecciated carbonate (F-4). The carbonate deposits show depletion in REE and Y in contrast to that determined in lutite. The formation of the carbonate mounds was related to local artesian seepage thermal water flows of moderate to relative high temperatures. Pressure differences between the low permeability host rock and the circulating fluids accounted for dilational fracturing and brecciation of the host sediment packages, which combined with precipitation of new carbonate and silica mineral phases. Locally, some carbonate mounds developed where groundwater

  15. Sedimentary environments and preservation biases limit sulfur isotope fractionation observed in pyrite, despite large microbial fractionations

    NASA Astrophysics Data System (ADS)

    Halevy, I.; Wing, B. A.; Wenk, C.; Guimond, C.

    2015-12-01

    Microbial S isotope fractionations close to the thermodynamic fractionation between sulfate and sulfide (~70‰) are encountered only at the slowest rates of sulfate reduction in laboratory cultures. In turn, the slowest laboratory reduction rates overlap with only the highest values of cell-specific sulfate reduction rates measured in marine sediments. This chain-of-logic implies that sulfate-reducing microbes in the marine sedimentary biosphere fractionate S isotopes at magnitudes close to the thermodynamic limit. Recent observations from sulfate-poor environments indicate that fractionations are large even at micromolar sulfate concentrations, in agreement with model predictions of near-thermodynamic S isotope fractionation at these sulfate concentrations as long as cell-specific sulfate reduction rates are low. Despite the expectation of large microbial fractionations, pyrite in both modern marine sediments and Phanerozoic sedimentary rocks records apparent fractionations ranging from 0 to more than 70‰. We suggest that the observed range of modern marine and geologic apparent fractionations recorded in pyrite does not reflect variability in intrinsic microbial behavior, but an early diagenetic modulation of large microbial fractionations, which are pinned to the thermodynamic limit by the low natural rates of sulfate reduction. With a diagenetic model developed in this study, we show that the entire range of apparent fractionations is possible with microbial fractionations at the thermodynamic limit. Apparent fractionations depend on a variety of physical parameters of the sedimentary environment like sedimentation rate, porosity, and organic matter content, most of which correlate with water depth. These findings, in combination with knowledge about the preservation potential of sediments deposited at different depths, make predictions for the observed geologic range of apparent fractionations, and ways in which it differs from the range in modern marine

  16. Constraining the Geological Time Scale for the Upper Cretaceous in the Edmonton Group: Western Canadian Sedimentary Basin

    NASA Astrophysics Data System (ADS)

    Heredia, B.; Gaylor, J. R.; Hilgen, F.; Kuiper, K.; Mezger, K.; Wijbrans, J. R.; Quidelleur, X.; Huesing, S.

    2011-12-01

    The Cretaceous period records evidence of sea-level changes, remarkably cyclic sedimentation, major perturbations in carbon cycles during anoxic events, and large scale igneous activity. Astronomically-tuned time scales are only partially consistent with recalculated Ar-Ar constraints for the Cretaceous-Paleogene (K-Pg) boundary, but differ in number and tuning of 405-kyr eccentricity related cycles. The exposures of Upper Cretaceous strata along the Red Deer River (Western Canadian Sedimentary Basin) offer a unique opportunity to examine aspects of marine, tectonic, and climatic influenced sediments. The uppermost part of the Knudsen Farm section is a well-preserved continuous section, mainly composed by climatically controlled alternations of silt and organic rich horizons, in which altered volcanic ash layers have been deposited. In this section, the K-Pg boundary has been placed at the base of a prominent coal layer (Nevis coal), approx. 24 m from the base of the c29r. We present a compilation of paleomagnetic data, chemical, colour and magnetic susceptibility proxies, and Ar-Ar, K-Ar and U-Pb (CA-TIMS) for the uppermost part of the Maastrichtian, including the base of the c29r to the K-Pg boundary and up to the lowermost Danian. High-resolution radioisotopic ages and the multi-proxy lithological and geochemical datasets are used to develop a cyclostratigraphic reconstruction of this interval, thus permitting the synchronisation of rock clocks close to the K-Pg boundary. This research is funded by the European Community's Seventh Framework Program (FP7/2007-2013) under grant agreement no [215458].

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

    USGS Publications Warehouse

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

    2011-01-01

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

  18. Basin-Scale nd Isotope Gradients in South Atlantic Marine Sedimentary Records

    NASA Astrophysics Data System (ADS)

    Ran, W.; Abouchami, W.; Zahn, R.; Masque, P.

    2012-12-01

    radiogenic ɛNd values, whereas variable Holocene Pa/Th are combined to less radiogenic ɛNd values. The radiogenic seawater Nd isotope signature is entirely consistent with a predominance at the site during the LGM of a water body different from present-day NADW (ɛNd=-13). Together with existing Nd isotope records [3, 4, 5] this demonstrates the existence of a basin scale North-South Nd isotope gradient consistent with the contention, previously drawn from meridional 231Pa/230Th offsets [1], of a more prominent northward advection of southern component water. The combined 231Pa/230Th - Nd isotope systematics of existing marine sedimentary records has important implication for the significance and interpretation of these proxies as tracers of the dynamics of the Atlantic MOC which will be discussed in view of existing models. [1] Negre et al., Nature, 2010, 468, 84-88. [2] Galer et al., Mineral. Mag., 2011, 75, 883. [3] Rutberg et al., Nature, 2000, 405, 935-938. [4] Piotrowski et al., 2005, Science, 307: 1933-1938. [5] Roberts et al., 2010, Science, 327: 75-77.

  19. Capability of ERTS-1 imagery to investigate geological and structural features in a sedimentary basin (Bassin Parisien, France)

    NASA Technical Reports Server (NTRS)

    Cavelier, C.; Scanvic, J. Y.; Weecksteen, G.; Zizerman, A.

    1973-01-01

    A preliminary study of the MSS imagery of a sedimentary basin whose structure is regular is reported. Crops and natural vegetation are distributed all over the site located under temperate climate. Ground data available concern plant species geology and tectonic and are correlated with results from ERTS 1 imagery. This comparison shows a good correlation. The main geological units are detected or enhanced by way of agricultural land use and/or natural vegetation. Alluvial deposits are outlined by vegetation grass land and poplar trees. Some spatial relationship of geostructures, suspected until now, are identified or extended in associating results from different spectral bands.

  20. Numerical simulations of complex temperature, burial, and erosion histories for sedimentary basins and their calibration: Examples from western Germany

    SciTech Connect

    Buker, C.; Littke, R.; Welte, D.H.

    1995-08-01

    The detailed and reliable reconstruction of the geological and thermal evolution of sedimentary basins forms the indispensable basis of any simulation of generation, migration and accumulation of hydrocarbons. For this purpose - although often not taken into account - analysing and quantifying the uplift and erosion history is as important as the subsidence and temperature history. The reconstruction of the timing of hydrocarbon generation, petroleum expulsion and migration and the changing reservoir characteristics is only possible based on such an integrated approach. Applying this technique on the Carboniferous Ruhr Basin and the Lower Saxony Basin (western Germany) by utilising 1-D and 2-D forward modeling approaches resulted in important and new quantitative information on their temperature, subsidence and erosion histories which are of fundamental geological interest. The basin evolution models were calibrated using vitrinite reflectance data, fluid inclusion temperatures, and apatite and zircon fission track data. The detailed knowledge of the geological and thermal basin evolution then allowed in combination with a new kinetic model for gas generation from coals the modeling of generation, migration and accumulation of methane from Carboniferous coal seams.

  1. Sedimentary facies and sequence stratigraphy of the Asmari Formation at Chaman-Bolbol, Zagros Basin, Iran

    NASA Astrophysics Data System (ADS)

    Amirshahkarami, Mahnaz; Vaziri-Moghaddam, Hossein; Taheri, Azizolah

    2007-03-01

    The Oligocene-Miocene Asmari Formation of the Zagros Basin is a thick sequence of shallow water carbonate. In the study area, it is subdivided into 14 microfacies that are distinguished on the basis of their depositional textures, petrographic analysis and fauna. Based on the paleoecology and lithology, four distinct depositional settings can be recognized: tidal flat, lagoon, barrier, and open marine. The Asmari Formation represents sedimentation on a carbonate ramp. In the inner ramp, the most abundant lithofacies are medium grained wackestone-packstone with imperforated foraminifera. The middle ramp is represented by packstone-grainstone to floatstone with a diverse assemblage of larger foraminifera with perforate wall, red algae, bryozoa, and echinoids. The outer ramp is dominated by argillaceous wackestone characterized by planktonic foraminifera and large and flat nummulitidae and lepidocyclinidae. Three third-order depositional sequences are recognized from deepening and shallowing trends in the depositional facies, changes in cycle stacking patterns, and sequence boundary features.

  2. Modeling of Wave Propagation in the Osaka Sedimentary Basin during the 2013 Awaji Island Earthquake (Mw5.8)

    NASA Astrophysics Data System (ADS)

    Asano, K.; Sekiguchi, H.; Iwata, T.; Yoshimi, M.; Hayashida, T.; Saomoto, H.; Horikawa, H.

    2013-12-01

    The three-dimensional velocity structure model for the Osaka sedimentary basin, southwest Japan is developed and improved based on many kinds of geophysical explorations for decades (e.g., Kagawa et al., 1993; Horikawa et al., 2003; Iwata et al., 2008). Recently, our project (Sekiguchi et al., 2013) developed a new three-dimensional velocity model for strong motion prediction of the Uemachi fault earthquake in the Osaka basin considering both geophysical and geological information by adding newly obtained exploration data such as reflection surveys, microtremor surveys, and receiver function analysis (hereafter we call UMC2013 model) . On April 13, 2013, an inland earthquake of Mw5.8 occurred in Awaji Island, which is close to the southwestern boundary of the aftershock area of the 1995 Kobe earthquake. The strong ground motions are densely observed at more than 100 stations in the basin. The ground motion lasted longer than four minutes in the Osaka urban area where its bedrock depth is about 1-2 km. This long-duration ground motions are mainly due to the surface waves excited in this sedimentary basin whereas the magnitude of this earthquake is moderate and the rupture duration is expected to be less than 5 s. In this study, we modeled long-period (more than 2s) ground motions during this earthquake to check the performance of the present UMC2013 model and to obtain a better constraint on the attenuation factor of sedimentary part of the basin. The seismic wave propagation in the region including the source and the Osaka basin is modeled by the finite difference method using the staggered grid solving the elasto-dynamic equations. The domain of 90km×85km×25.5km is modeled and discretized with a grid spacing of 50 m. Since the minimum S-wave velocity of the UMC2013 model is about 250 m/s, this calculation is valid up to the period of about 1 s. The effect of attenuation is included in the form of Q(f)=Q0(T0/T) proposed by Graves (1996). A PML is implemented in

  3. Geochemistry of Neogene sedimentary rocks from Borneo Basin, Malaysia: implications on paleo-weathering, provenance and tectonic setting

    NASA Astrophysics Data System (ADS)

    Ramasmay, N.; Roy, P.; MP, J.; Rufino, L.; Franz, L. K.; Viswanathan, P. M.

    2013-05-01

    Multi-element geochemistry and mineralogy are used to characterize the chemical composition, degree of paleo-weathering, provenance and tectonic settingsof the Neogene sedimentary rocks of Borneo Basin from east Malaysia. The sedimentary rocks are classified as extremely weathered sandstones (i.e. wacke, arkose, litharenite, Fe-sandstone and quartz arenite). Higher values of both weathering indices of alteration (i.e. CIA>83 and PIA>89) suggest that the sandstones have undergone extreme chemical weathering. Absence of any feldspar in the mineralogical analysis indicates its degradation during the weathering. Except for the quartz arenite, all other sandstones are characterized by post-depositional K-metasomatism and zircon enrichment through sediment recycling. The geochemical characteristics suggest a mixed-nature provenance for the sandstones with contribution coming from both felsic and mafic igneous rocks. Enriched Cr in quartz arenite and Fe-sandstone are related to contribution from ophiolite or fractionation of Cr-bearing minerals. The inferred tectonic settings are variable and suggest a complex nature of tectonic environment in the basin.

  4. The evolution of the Danube gateway between Central and Eastern Paratethys (SE Europe): Insight from numerical modelling of the causes and effects of connectivity between basins and its expression in the sedimentary record

    NASA Astrophysics Data System (ADS)

    Leever, K. A.; Matenco, L.; Garcia-Castellanos, D.; Cloetingh, S. A. P. L.

    2011-04-01

    The Pannonian and Dacic Basins in SE Europe are presently connected by the Danube River across the South Carpathians, to which they are in a back-arc and foreland position respectively. Part of the Paratethys realm during the Neogene, open water communication between the basins was interrupted by the Late Miocene uplift of the Carpathians. Different mechanisms have been proposed for the formation of the Danube gateway: capture of the upstream lake or an upstream river or incision of an antecedent river. Estimates on its age range from Late Miocene to Quaternary. A related issue is the effect of the large Mediterranean sea level fall related to the Messinian Salinity Crisis on the Paratethys subbasins, specifically the "isolated" Pannonian Basin. In a synthetic numerical modelling study, using a pseudo-3D code integrating tectonics, surface processes and isostasy, we addressed the causes and effects of changes in connectivity between two large sedimentary basins separated by an elevated barrier. Specifically, we aimed to find the expression of connectivity events in the sedimentary record in general and the consequences for the evolution of the Pannonian-Dacic area in particular. We studied a range of parameters including the geometry and uplift rate of the barrier, downstream sea level change and lithosphere rigidity. We found that changes in connectivity are expressed in the sedimentary record through their effect on base level in the upstream basin and supply in the downstream basin. The most important factors controlling the response are the elevation difference between the basins and the upstream accommodation space at the time of reconnection. The most pronounced effect of reconnection through lake capture is predicted for a large elevation difference and limited upstream accommodation space. Downstream increase in sediment supply is dependent on the latter rather than the reconnection event itself. Of the parameters we tested, the rigidity of the lithosphere

  5. Geochemistry and origin of formation waters in the western Canada sedimentary basin-I. Stable isotopes of hydrogen and oxygen

    USGS Publications Warehouse

    Hitchon, B.; Friedman, I.

    1969-01-01

    Stable isotopes of hydrogen and oxygen, together with chemical analyses, were determined for 20 surface waters, 8 shallow potable formation waters, and 79 formation waters from oil fields and gas fields. The observed isotope ratios can be explained by mixing of surface water and diagenetically modified sea water, accompanied by a process which enriches the heavy oxygen isotope. Mass balances for deuterium and total dissolved solids in the western Canada sedimentary basin demonstrate that the present distribution of deuterium in formation waters of the basin can be derived through mixing of the diagenetically modified sea water with not more than 2.9 times as much fresh water at the same latitude, and that the movement of fresh water through the basin has redistributed the dissolved solids of the modified sea water into the observed salinity variations. Statistical analysis of the isotope data indicates that although exchange of deuterium between water and hydrogen sulphide takes place within the basin, the effect is minimized because of an insignificant mass of hydrogen sulphide compared to the mass of formation water. Conversely, exchange of oxygen isotopes between water and carbonate minerals causes a major oxygen-18 enrichment of formation waters, depending on the relative masses of water and carbonate. Qualitative evidence confirms the isotopic fractionation of deuterium on passage of water through micropores in shales. ?? 1969.

  6. Seismic Hazard Maps for Seattle, Washington, Incorporating 3D Sedimentary Basin Effects, Nonlinear Site Response, and Rupture Directivity

    USGS Publications Warehouse

    Frankel, Arthur D.; Stephenson, William J.; Carver, David L.; Williams, Robert A.; Odum, Jack K.; Rhea, Susan

    2007-01-01

    This report presents probabilistic seismic hazard maps for Seattle, Washington, based on over 500 3D simulations of ground motions from scenario earthquakes. These maps include 3D sedimentary basin effects and rupture directivity. Nonlinear site response for soft-soil sites of fill and alluvium was also applied in the maps. The report describes the methodology for incorporating source and site dependent amplification factors into a probabilistic seismic hazard calculation. 3D simulations were conducted for the various earthquake sources that can affect Seattle: Seattle fault zone, Cascadia subduction zone, South Whidbey Island fault, and background shallow and deep earthquakes. The maps presented in this document used essentially the same set of faults and distributed-earthquake sources as in the 2002 national seismic hazard maps. The 3D velocity model utilized in the simulations was validated by modeling the amplitudes and waveforms of observed seismograms from five earthquakes in the region, including the 2001 M6.8 Nisqually earthquake. The probabilistic seismic hazard maps presented here depict 1 Hz response spectral accelerations with 10%, 5%, and 2% probabilities of exceedance in 50 years. The maps are based on determinations of seismic hazard for 7236 sites with a spacing of 280 m. The maps show that the most hazardous locations for this frequency band (around 1 Hz) are soft-soil sites (fill and alluvium) within the Seattle basin and along the inferred trace of the frontal fault of the Seattle fault zone. The next highest hazard is typically found for soft-soil sites in the Duwamish Valley south of the Seattle basin. In general, stiff-soil sites in the Seattle basin exhibit higher hazard than stiff-soil sites outside the basin. Sites with shallow bedrock outside the Seattle basin have the lowest estimated hazard for this frequency band.

  7. Geodynamics of flat-slab subduction, sedimentary basin development, and hydrocarbon systems along the southern Alaska convergent plate margin

    NASA Astrophysics Data System (ADS)

    Finzel, Emily S.

    Combining field-based geologic studies and numerical modeling provides a robust tool for evaluating the geodynamics of convergent margins. Southern Alaska is arguably the most tectonically active part of the convergent margin of western North America. This conceptual approach has been used to interpret the modern basin dynamics, as well as key stages in the Cenozoic development of this region, including spreading-ridge and flat-slab subduction. New macrofossil, palynological, and lithostratigraphic data for the Bear Lake Formation in the Bristol Bay retroarc basin allow us to construct the first chronostratigraphic framework for this formation, and indicate deposition during Middle and Late Miocene time in a regional transgressive estuarine depositional system. In the Cook Inlet forearc basin, new detrital zircon U-Pb geochronology, rare earth element geochemistry, and clast compositional data from middle Eocene-Pliocene strata demonstrate the importance of sediment sources located in the retroarc region and along strike within the basin. The Yakutat microplate has recently been reinterpreted to represent buoyant crust that is presently subducting at a shallow angle beneath southern Alaska. Integration of stratigraphic, geochronologic, and thermochronologic data indicate that in the flat-slab region, exhumation initiated ca. 43 Ma and migrated inboard, magmatism ceased at ca. 32 Ma, and deposition in sedimentary basins ended by ca. 23 Ma. Sedimentary basins positioned along the western and northern perimeter of the flat-slab region record enhanced subsidence and sediment delivery from the flat-slab region beginning in late Oligocene and middle Miocene time respectively. The discrete contributions of unique driving forces for lithospheric deformation in western Canada and Alaska have not been quantified in detail, so their relative role in influencing deformation has remained unresolved. Using finite element models, we calculate a continuous strain rate and velocity

  8. Effect of surrounding fault on distributed fault of blind reverse fault in sedimentary basin - Uemachi Faults, Osaka Basin, Southwest Japan -

    NASA Astrophysics Data System (ADS)

    Inoue, N.

    2012-12-01

    Several large cities and metropolitan areas, such as Osaka and Kobe are located in the Osaka basin, which has been filled by the Pleistocene Osaka group and the later sediments. The basin is surrounded by E-W trending strike slip faults and N-S trending reverse faults. The N-S trending 42-km-long Uemachi faults traverse in the central part of the Osaka city. The various geological, geophysical surveys, such as seismic reflection, micro tremor, gravity surveys and deep boreholes, revealed the complex basement configuration along the Uemachi faults. The depth of the basement is shallow in the central part of the Osaka plain. The Uemachi faults are locates on the western side of the basement upland. In the central part of the Uemachi faults, the displacement decreases. The fault model of the Uemachi faults consists of the two parts, the north and south parts. The NE-SW trending branch faults, Suminoe and Sakuragawa flexures, are also recognized based on various surveys around the central part. Kusumoto et al. (2001) reported that surrounding faults enable to form the basement configuration without the Uemachi faults model based on a dislocation model. Inoue et al. (2011) performed various parameter studies for dislocation model and gravity changes based on simplified faults model, which were designed based on the distribution of the real faults. The model was consisted of 7 faults including the Uemachi faults. In this study, the Osaka-wan fault was considered for the dislocation model. The results show the basement configuration including NE-SW branch faults. The basement configuration differs from the subsurface structure derived from the investigation of abundance geotechnical borehole data around the central part of the Uemachi faults. The tectonic developing process including the erosion and sea level change are require to understanding the structure from the basement to the surface of the Uemachi Fault Zone. This research is partly funded by the Comprehensive

  9. Basement configuration of the West Bengal sedimentary basin, India as revealed by seismic refraction tomography: its tectonic implications

    NASA Astrophysics Data System (ADS)

    Damodara, N.; Rao, V. Vijaya; Sain, Kalachand; Prasad, A. S. S. S. R. S.; Murty, A. S. N.

    2017-03-01

    Understanding the sedimentary thickness, structure and tectonics of the West Bengal basin is attempted using pseudo 3-D configuration derived from the first arrival seismic refraction data. Velocity images of the West Bengal basin are derived using traveltime tomography along four profiles. The models are assessed for their reliability through chi-squares estimates, rms residual, traveltime fit, rays traced through the models and resolution by checkerboard tests. Tomographic images depict smooth velocity variations of Recent, Quaternary and Tertiary sediments of velocity 1.8-4.3 km s-1 deposited over the Rajmahal trap of 4.8 km s-1 velocity and the basement (5.9 km s-1) down to a maximum depth of 16 km. The present study indicates a south-easterly dip of basin as evidenced from the pseudo 3-D configuration. The basement depth along the seismic profiles varies from 1 to 16 km depending on its location in the basin. It is shallow in the north & west and deep in the east & south. The depth of the basement on the stable shelf of the basin in the west gently increases to about 8 km and dips to a maximum depth of 16 km in the deep basin part within a short distance in the east. The study identifies a regional feature, known as the Shelf break or the Hinge zone, where stable Indian shield ends and a sharp increase in sediment thickness occurs. The Hinge zone may represent the relict of continental and proto-oceanic crustal boundary formed during the rifting of India from Antarctica. The regional gravity map of the Bengal basin prepared in this study clearly brings out the Hinge zone with a linear gravity high that is compatible with seismic data. Presence of Shelf break/Hinge zone and Rajmahal volcanism in the basin suggests the influence of rifting of India from the combined Antarctica-Australia at ˜130 Ma due to mantle plume activity on the structure and tectonics of the West Bengal basin. These features along with the elevated rift shoulder are in agreement with the

  10. Basement configuration of the West Bengal sedimentary basin, India as revealed by seismic refraction tomography: its tectonic implications

    NASA Astrophysics Data System (ADS)

    Damodara, N.; Rao, V. Vijaya; Sain, Kalachand; Prasad, Asssrs; Murty, Asn

    2017-01-01

    SUMMARYUnderstanding the <span class="hlt">sedimentary</span> thickness, structure and tectonics of the West Bengal <span class="hlt">basin</span> is attempted using pseudo 3-D configuration derived from the first arrival seismic refraction data. Velocity images of the West Bengal <span class="hlt">basin</span> are derived using traveltime tomography along four profiles. The models are assessed for their reliability through chi-squares estimates, rms residual, traveltime fit, rays traced through the models, and resolution by checkerboard tests. Tomographic images depict smooth velocity variations of Recent, Quaternary and Tertiary sediments of velocity 1.8-4.3 km/s deposited over the Rajmahal trap of 4.8 km/s velocity and the basement (5.9 km/s) down to a maximum depth of 16 km. The present study indicates a south-easterly dip of <span class="hlt">basin</span> as evidenced from the pseudo 3-D configuration. The basement depth along the seismic profiles varies from 1 km to 16 km depending on its location in the <span class="hlt">basin</span>. It is shallow in the north & west and deep in the east & south. The depth of the basement on the stable shelf of the <span class="hlt">basin</span> in the west gently increases to about 8 km and dips to a maximum depth of 16 km in the deep <span class="hlt">basin</span> part within a short distance in the east. The study identifies a regional feature, known as the Shelf break or the Hinge zone, where stable Indian shield ends and a sharp increase in sediment thickness occurs. The Hinge zone may represent the relict of continental and proto-oceanic crustal boundary formed during the rifting of India from Antarctica. The regional gravity map of the Bengal <span class="hlt">basin</span> prepared in this study clearly brings out the Hinge zone with a linear gravity high that is compatible with seismic data. Presence of Shelf break / Hinge zone and Rajmahal volcanism in the <span class="hlt">basin</span> suggests the influence of rifting of India from the combined Antarctica-Australia at ˜130 Ma due to mantle plume activity on the structure and tectonics of the West Bengal <span class="hlt">basin</span>. These features along with the elevated rift shoulder are in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeCoA.186..120R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeCoA.186..120R"><span><span class="hlt">Sedimentary</span> pyrite δ34S differs from porewater sulfide in Santa Barbara <span class="hlt">Basin</span>: Proposed role of organic sulfur</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Raven, Morgan Reed; Sessions, Alex L.; Fischer, Woodward W.; Adkins, Jess F.</p> <p>2016-08-01</p> <p>Santa Barbara <span class="hlt">Basin</span> sediments host a complex network of abiotic and metabolic chemical reactions that knit together the carbon, sulfur, and iron cycles. From a 2.1-m sediment core collected in the center of the <span class="hlt">basin</span>, we present high-resolution profiles of the concentrations and isotopic compositions of all the major species in this system: sulfate, sulfide (∑H2S), elemental sulfur (S0), pyrite, extractable organic sulfur (OS), proto-kerogen S, total organic and dissolved inorganic carbon, and total and reducible iron. Below 10 cm depth, the core is characterized by low apparent sulfate reduction rates (<0.01 mM/yr) except near the sulfate-methane transition zone. Surprisingly, pyrite forming in shallow sediments is ∼30‰ more 34S-depleted than coexisting ∑H2S in porewater. S0 has the same strongly 34S-depleted composition as pyrite where it forms near the sediment-water interface, though not at depth. This pattern is not easily explained by conventional hypotheses in which <span class="hlt">sedimentary</span> pyrite derives from abiotic reactions with porewater ∑H2S or from the products of S0 disproportionation. Instead, we propose that pyrite formation in this environment occurs within sulfate reducing microbial aggregates or biofilms, where it reflects the isotopic composition of the immediate products of bacterial sulfate reduction. Porewater ∑H2S in Santa Barbara <span class="hlt">Basin</span> may be more 34S-enriched than pyrite due to equilibration with relatively 34S-enriched OS. The difference between OS and pyrite δ34S values would then reflect the balance between microbial sulfide formation and the abundance of exchangeable OS. Both OS and pyrite δ34S records thus have the potential to provide valuable information about biogeochemical cycles and redox structure in <span class="hlt">sedimentary</span> paleoenvironments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.H23E1439B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.H23E1439B"><span>Reactive transport modeling of dissolved oxygen migration and consumption in a <span class="hlt">sedimentary</span> <span class="hlt">basins</span> affected by a deglaciation event</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bea, S. A.; Mayer, K. U.; MacQuarrie, K. T.</p> <p>2012-12-01</p> <p>In intracratonic <span class="hlt">sedimentary</span> <span class="hlt">basins</span>, geochemical conditions are currently reducing at depth. Deep groundwater flow systems are driven primarily by salinity differences, topographic gradients and recharge derived from precipitation; these systems are also influenced by the hydrostratigraphy of the <span class="hlt">basin</span>. However, during periods of glacial melt water production (i.e., deglaciation events), the melting of ice sheets may alter the patterns of freshwater infiltration, potentially resulting in enhanced recharge of glacial melt water containing relatively high concentrations of dissolved oxygen. Reactive transport modeling can be used to understand the evolution of geochemical conditions and redox-buffering capacity of these formations. Dissolved oxygen will interact with reduced mineral phases that are present in the <span class="hlt">sedimentary</span> units (e.g., chlorite) or with solid organic matter causing oxygen consumption. Processes included in the model are density-driven flow and transport, vertical mechanical deformation, as well as chemical reactions (aqueous complexation, mineral dissolution and precipitation including evaporites, sulfates and carbonates, cation-exchange, redox processes involving the decomposition of organic matter, dissolution of Fe-bearing minerals, biotite and chlorite, and the oxidation of ferrous iron and sulfide). Transient boundary conditions are imposed in the upper part of the model to mimic ice sheet advance and retreat. Simulation results indicate that the presence of dense brines at depth results in low groundwater velocities during glacial meltwater infiltration, restricting the ingress of oxygenated waters in the <span class="hlt">basin</span>. In addition, due to the abundance of reduced mineral phases and solid organic matter in these formations, geochemical processes causing oxygen consumption are restricted to shallow aquifers, further limiting the ingress of oxygenated waters to the first 100 m in the main aquifers (i.e., sandstones) and 50 m in the carbonates aquifers</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70035612','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70035612"><span>Middle Jurassic Topawa group, Baboquivari Mountains, south-central Arizona: Volcanic and <span class="hlt">sedimentary</span> record of deep <span class="hlt">basins</span> within the Jurassic magmatic arc</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Haxel, G.B.; Wright, J.E.; Riggs, N.R.; Tosdal, R.M.; May, D.J.</p> <p>2005-01-01</p> <p>Among supracrustal sequences of the Jurassic magmatic arc of the southwestern Cordillera, the Middle Jurassic Topawa Group, Baboquivari Mountains, south-central Arizona, is remarkable for its lithologic diversity and substantial stratigraphic thickness, ???8 km. The Topawa Group comprises four units (in order of decreasing age): (1) Ali Molina Formation-<span class="hlt">largely</span> pyroclastic rhyolite with interlayered eolian and fluvial arenite, and overlying conglomerate and sandstone; (2) Pitoikam Formation-conglomerate, <span class="hlt">sedimentary</span> breccia, and sandstone overlain by interbedded silt- stone and sandstone; (3) Mulberry Wash Formation-rhyolite lava flows, flow breccias, and mass-flow breccias, with intercalated intraformational conglomerate, <span class="hlt">sedimentary</span> breccia, and sandstone, plus sparse within-plate alkali basalt and comendite in the upper part; and (4) Tinaja Spring Porphyry-intrusive rhyolite. The Mulberry Wash alkali basalt and comendite are genetically unrelated to the dominant calcalkaline rhyolite. U-Pb isotopic analyses of zircon from volcanic and intrusive rocks indicate the Topawa Group, despite its considerable thickness, represents only several million years of Middle Jurassic time, between approximately 170 and 165 Ma. <span class="hlt">Sedimentary</span> rocks of the Topawa Group record mixing of detritus from a minimum of three sources: a dominant local source of porphyritic silicic volcanic and subvolcanic rocks, identical or similar to those of the Topawa Group itself; Meso- proterozoic or Cambrian conglomerates in central or southeast Arizona, which contributed well-rounded, highly durable, polycyclic quartzite pebbles; and eolian sand fields, related to Middle Jurassic ergs that lay to the north of the magmatic arc and are now preserved on the Colorado Plateau. As the Topawa Group evidently represents only a relatively short interval of time, it does not record long-term evolution of the Jurassic magmatic arc, but rather represents a Middle Jurassic "stratigraphic snapshot" of the arc</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..1413197M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..1413197M"><span>Effects of <span class="hlt">large</span> sea-level variations in connected <span class="hlt">basins</span>: the Dacian - Black Sea system of the Eastern Paratethys</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Munteanu, I.; Matenco, L.; Dinu, C.; Cloetingh, S.</p> <p>2012-04-01</p> <p>Sea-level changes provide an important control on the interplay between accommodation space and sediment supply, in particular for shallow-water <span class="hlt">basins</span> where the available space is limited. Sediment exchange between connected <span class="hlt">basins</span> separated by a subaqueous sill (bathymetric threshold) is still not well understood. When sea-level falls below the bathymetric level of this separating sill, the shallow-water <span class="hlt">basin</span> evolution is controlled by its erosion and rapid fill. Once this marginal <span class="hlt">basin</span> is filled, the <span class="hlt">sedimentary</span> depocenter shifts to the open marine <span class="hlt">basin</span> (outward shift). With new accommodation space created during the subsequent sea-level rise, sediment depocenter shifts backwards to the marginal <span class="hlt">basin</span> (inward shift). This new conceptual model is tested here in the context of Late Miocene to Quaternary evolution of the open connection between Dacian and Black Sea <span class="hlt">basins</span>. By the means of seismic sequence stratigraphic analysis of the Miocene-Pliocene evolution of this Eastern Paratethys domain, this case study demonstrates these shifts in <span class="hlt">sedimentary</span> depocenter between <span class="hlt">basins</span>. An outward shift occurs with a delay that corresponds to the time required to fill the remaining accommodation space in the Dacian <span class="hlt">Basin</span> below the sill that separates it from the Black Sea. This study provides novel insight on the amplitude and <span class="hlt">sedimentary</span> geometry of the Messinian Salinity Crisis (MSC) event in the Black Sea. A <span class="hlt">large</span> (1.3 - 1.7km) sea-level drop is demonstrated by quantifying coeval sedimentation patterns that change to mass-flows and turbiditic deposits in the deep-sea part of this main sink. The post-MSC sediment routing continued into the present-day pattern of Black Sea rivers discharge.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12.8247K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12.8247K"><span>Organic-geochemical characterization of <span class="hlt">sedimentary</span> organic matter deposited during the Valanginian carbon isotope excursion (Vocontian <span class="hlt">Basin</span>, SE France)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kujau, Ariane; Heimhofer, Ulrich; Ostertag-Henning, Christian; Mutterlose, Jörg; Gréselle, Benjamin</p> <p>2010-05-01</p> <p>Terrestrial and marine <span class="hlt">sedimentary</span> archives covering the Valanginian interval (136.8-133.9 Ma, Ogg et al., 2004) display a distinct positive delta13C-isotope excursion (CIE) of ~2.5 permil (Lini et al., 1992; Gröcke et al., 2005). The carbon isotope shift spans ~2.0 Ma and has been interpreted to reflect severe perturbations of the Early Cretaceous carbon cycle and paleoenvironmental conditions. According to different authors, the Valanginian CIE was accompanied by enhanced volcanic activity of the Paranà-Etendeka <span class="hlt">large</span> igneous flood basalts, enhanced pCO2 (Lini et al., 1992; Weissert et al., 1998), widespread biocalcification crisis (Erba et al., 2004) and a distinct climatic cooling as evidenced by ice-rafted debris and glendonites from high-latitude sites. In addition, the positive CIE was assigned to be the result of an anoxic event, named the Weissert OAE (Erba et al., 2004). In this study, we investigate the composition and distribution of <span class="hlt">sedimentary</span> organic matter (OM) deposited in a hemipelagic setting before, during, and after the Valanginian CIE. The aim of this study is to provide a detailed view on possible changes in OM deposition during a time of major paleoenvironmental and climatic stress. The chosen approach combines sedimentological and chemostratigraphical information (delta13Ccarb) with geochemical analysis of the bulk OM (incl. TOC, C/N, delta13Corg, Rock-Eval) and biomarker data. For this study, hemipelagic deposits located in the <span class="hlt">basinal</span> part of the Vocontian Trough (SE France) covering the late Valanginian to early Hauterivian (Campylotoxus Zone to Radiatus Zone) (Gréselle 2007) have been sampled on a high resolution (sampling spacing of ~2/m). A total of three sections has been logged (La Charce, Vergol, Morenas), which consist of hemipelagic marl-limestone alternations and which allow for the construction of a composite succession. The delta13Ccarb values range between ~0.1 and 2.7 permil and show a characteristic stratigraphic trend</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoJI.204.1678A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoJI.204.1678A"><span>Modelling of wave propagation and attenuation in the Osaka <span class="hlt">sedimentary</span> <span class="hlt">basin</span>, western Japan, during the 2013 Awaji Island earthquake</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Asano, Kimiyuki; Sekiguchi, Haruko; Iwata, Tomotaka; Yoshimi, Masayuki; Hayashida, Takumi; Saomoto, Hidetaka; Horikawa, Haruo</p> <p>2016-03-01</p> <p>On 2013 April 13, an inland earthquake of Mw 5.8 occurred in Awaji Island, which forms the western boundary of the Osaka <span class="hlt">sedimentary</span> <span class="hlt">basin</span> in western Japan. The strong ground motion data were collected from more than 100 stations within the <span class="hlt">basin</span> and it was found that in the Osaka Plain, the pseudo velocity response spectra at a period of around 6.5 s were significantly larger than at other stations of similar epicentral distance outside the <span class="hlt">basin</span>. The ground motion lasted longer than 3 min in the Osaka Plain where its bedrock depth spatially varies from approximately 1 to 2 km. We modelled long-period (higher than 2 s) ground motions excited by this earthquake, using the finite difference method assuming a point source, to validate the present velocity structure model and to obtain better constraint of the attenuation factor of the <span class="hlt">sedimentary</span> part of the <span class="hlt">basin</span>. The effect of attenuation in the simulation was included in the form of Q(f) = Q0(f/f0), where Q0 at a reference frequency f0 was given by a function of the S-wave velocity, Q0 = αVS. We searched for appropriate Q0 values by changing α for a fixed value of f0 = 0.2 Hz. It was found that values of α from 0.2 to 0.5 fitted the observations reasonably well, but that the value of α = 0.3 performed best. Good agreement between the observed and simulated velocity waveforms was obtained for most stations within the Osaka <span class="hlt">Basin</span> in terms of both amplitude and ground motion duration. However, underestimation of the pseudo velocity response spectra in the period range of 5-7 s was recognized in the central part of the Osaka Plain, which was caused by the inadequate modelling of later phases or wave packets in this period range observed approximately 2 min after the direct S-wave arrival. We analysed this observed later phase and concluded that it was a Love wave originating from the direction of the east coast of Awaji Island.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.4476F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.4476F"><span>New approaches in the indirect quantification of thermal rock properties in <span class="hlt">sedimentary</span> <span class="hlt">basins</span>: the well-log perspective</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fuchs, Sven; Balling, Niels; Förster, Andrea</p> <p>2016-04-01</p> <p>Numerical temperature models generated for geodynamic studies as well as for geothermal energy solutions heavily depend on rock thermal properties. Best practice for the determination of those parameters is the measurement of rock samples in the laboratory. Given the necessity to enlarge databases of subsurface rock parameters beyond drill core measurements an approach for the indirect determination of these parameters is developed, for rocks as well a for geological formations. We present new and universally applicable prediction equations for thermal conductivity, thermal diffusivity and specific heat capacity in <span class="hlt">sedimentary</span> rocks derived from data provided by standard geophysical well logs. The approach is based on a data set of synthetic <span class="hlt">sedimentary</span> rocks (clastic rocks, carbonates and evaporates) composed of mineral assemblages with variable contents of 15 major rock-forming minerals and porosities varying between 0 and 30%. Petrophysical properties are assigned to both the rock-forming minerals and the pore-filling fluids. Using multivariate statistics, relationships then were explored between each thermal property and well-logged petrophysical parameters (density, sonic interval transit time, hydrogen index, volume fraction of shale and photoelectric absorption index) on a regression sub set of data (70% of data) (Fuchs et al., 2015). Prediction quality was quantified on the remaining test sub set (30% of data). The combination of three to five well-log parameters results in predictions on the order of <15% for thermal conductivity and thermal diffusivity, and of <10% for specific heat capacity. Comparison of predicted and benchmark laboratory thermal conductivity from deep boreholes of the Norwegian-Danish <span class="hlt">Basin</span>, the North German <span class="hlt">Basin</span>, and the Molasse <span class="hlt">Basin</span> results in 3 to 5% larger uncertainties with regard to the test data set. With regard to temperature models, the use of calculated TC borehole profiles approximate measured temperature logs with an</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRB..121.2235W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRB..121.2235W"><span>The Cenozoic growth of the Qilian Shan in the northeastern Tibetan Plateau: A <span class="hlt">sedimentary</span> archive from the Jiuxi <span class="hlt">Basin</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Weitao; Zhang, Peizhen; Pang, Jianzhang; Garzione, Carmala; Zhang, Huiping; Liu, Caicai; Zheng, Dewen; Zheng, Wenjun; Yu, Jingxing</p> <p>2016-04-01</p> <p><span class="hlt">Sedimentary</span> deposits in Tibetan <span class="hlt">Basins</span> archive the spatial-temporal patterns of the deformation and surface uplift processes that created the area's high topography during the Cenozoic India-Asia collision. In this study, new stratigraphic investigation of the Caogou section from the Jiuxi <span class="hlt">Basin</span> in the northeasternmost part of Tibetan Plateau provides chronologic constraints on the deformation and northward growth of the plateau. Magnetostratigraphic analysis results suggest that the age of the studied ~1000 m thick section spans from ~24.2 Ma to 2.8 Ma. Detailed sedimentology and apatite fission track (AFT) analyses reveal that variations in the clast provenance, lithofacies, sediment accumulation rates, and AFT lag times occurred at ~13.5-10.5 Ma. We interpret these changes as in response to the initial uplift of the North Qilian Shan. In addition, paleomagnetic declination results from the section indicate a clockwise rotation of the Jiuxi <span class="hlt">Basin</span> before ~13.5 Ma, which was followed by a subsequent counterclockwise rotation during 13.5-9 Ma. This reversal in rotation direction may be directly related to left-lateral strike-slip activity along the easternmost segment of the Altyn Tagh Fault. Combined with previous studies, we suggest that movement on the western part of the Altyn Tagh Fault was probably initiated during the Oligocene (>30 Ma) and that fault propagation to its eastern tip occurred during the middle-late Miocene.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JSAES..65...79R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JSAES..65...79R"><span>Deformation within the Pisco <span class="hlt">Basin</span> <span class="hlt">sedimentary</span> record (southern Peru): Stratabound orthogonal vein sets and their impact on fault development</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rustichelli, Andrea; Di Celma, Claudio; Tondi, Emanuele; Bianucci, Giovanni</p> <p>2016-01-01</p> <p>This outcrop-based study reports diffuse joints and veins, normal to strike-slip fault zones and minor folds that developed, from Miocene to Quaternary, within the clastic to siliceous <span class="hlt">sedimentary</span> record of the forearc Pisco <span class="hlt">Basin</span> of southern Peru. Patterns, orientations, dimensional parameters and other outcrop-scale characteristics of the various deformation features are illustrated and their genetic mechanisms and timing of development are inferred. These new structural data and interpretations allow a better constraint of the structural style and evolution of the Pisco <span class="hlt">Basin</span>, and can represent useful guidelines for characterizing the outcrop-scale deformation affecting similar forearc <span class="hlt">basins</span> along the Peruvian coast. Major results of this study are that the development of the documented deformation features, their patterns, dimensional parameters and kinematics seem influenced by local perturbations of the paleostress field by mechanic processes partly independent of plate tectonics forces. These processes include strain localization on both pre-existing and progressively forming new structural discontinuities, and cyclic switches of the horizontal, principal stress axes σ2 and σ3. In particular, we discuss how different normal fault patterns, from sub-parallel to multidirectional/polygonal, could form in a same deformation phase in response of the local σ2/σ3 magnitude ratio, as an evolution of stratabound, mutually orthogonal vein sets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120009917','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120009917"><span>Distribution, Statistics, and Resurfacing of <span class="hlt">Large</span> Impact <span class="hlt">Basins</span> on Mercury</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fassett, Caleb I.; Head, James W.; Baker, David M. H.; Chapman, Clark R.; Murchie, Scott L.; Neumann, Gregory A.; Oberst, Juergen; Prockter, Louise M.; Smith, David E.; Solomon, Sean C.; Strom, Robert G.; Xiao, Zhiyong; Zuber, Maria T.</p> <p>2012-01-01</p> <p>The distribution and geological history of <span class="hlt">large</span> impact <span class="hlt">basins</span> (diameter D greater than or equal to 300 km) on Mercury is important to understanding the planet's stratigraphy and surface evolution. It is also informative to compare the density of impact <span class="hlt">basins</span> on Mercury with that of the Moon to understand similarities and differences in their impact crater and <span class="hlt">basin</span> populations [1, 2]. A variety of impact <span class="hlt">basins</span> were proposed on the basis of geological mapping with Mariner 10 data [e.g. 3]. This <span class="hlt">basin</span> population can now be re-assessed and extended to the full planet, using data from the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft. Note that small-to- medium-sized peak-ring <span class="hlt">basins</span> on Mercury are being examined separately [4, 5]; only the three largest peak-ring <span class="hlt">basins</span> on Mercury overlap with the size range we consider here. In this study, we (1) re-examine the <span class="hlt">large</span> <span class="hlt">basins</span> suggested on the basis of Mariner 10 data, (2) suggest additional <span class="hlt">basins</span> from MESSENGER's global coverage of Mercury, (3) assess the size-frequency distribution of mercurian <span class="hlt">basins</span> on the basis of these global observations and compare it to the Moon, and (4) analyze the implications of these observations for the modification history of <span class="hlt">basins</span> on Mercury.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10128315','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10128315"><span>[Mechano-chemical self-organization and nonlinear dynamics in <span class="hlt">sedimentary</span> <span class="hlt">basins</span>]. Technical progress report</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Not Available</p> <p>1993-03-01</p> <p>The central theme of this project is that the reaction, transport and mechanical (RTM) processes affect each other so strongly that <span class="hlt">basin</span> diagenesis takes on a qualitatively different behavior than what would be predicted by the analysis of the individual processes separately. In Figs. 1 and 2 we see schematic <span class="hlt">basin</span> cross-sections that emphasize a few of the diagenetic phenomena arising from the strong coupling of RTM processes. <span class="hlt">Basin</span> diagenesis allows for a great richness of phenomena (Fig. 1) including the genesis of a (formation localized) basal seal, dynamic transbasinal top seal, fault related side seals, episodic fluid release and smaller scale compartmentation within and adjacent to the <span class="hlt">basin</span>-scale overpressured compartment and also (Fig. 2) fingered reaction fronts and upwardly migrating petroleum and auto-localized petroleum (through petroleum-induced porosity preservation). The phenomena of Figs. 1 and 2 arise through feedback loops in the RTM process network.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/7018941','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/7018941"><span>[Mechano-chemical self-organization and nonlinear dynamics in <span class="hlt">sedimentary</span> <span class="hlt">basins</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Not Available</p> <p>1993-01-01</p> <p>The central theme of this project is that the reaction, transport and mechanical (RTM) processes affect each other so strongly that <span class="hlt">basin</span> diagenesis takes on a qualitatively different behavior than what would be predicted by the analysis of the individual processes separately. In Figs. 1 and 2 we see schematic <span class="hlt">basin</span> cross-sections that emphasize a few of the diagenetic phenomena arising from the strong coupling of RTM processes. <span class="hlt">Basin</span> diagenesis allows for a great richness of phenomena (Fig. 1) including the genesis of a (formation localized) basal seal, dynamic transbasinal top seal, fault related side seals, episodic fluid release and smaller scale compartmentation within and adjacent to the <span class="hlt">basin</span>-scale overpressured compartment and also (Fig. 2) fingered reaction fronts and upwardly migrating petroleum and auto-localized petroleum (through petroleum-induced porosity preservation). The phenomena of Figs. 1 and 2 arise through feedback loops in the RTM process network.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/675978','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/675978"><span>Petroleum resource potential of <span class="hlt">sedimentary</span> <span class="hlt">basins</span> on the Pacific Margin of Canada. Open File Number 3629</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hannigan, P.K.</p> <p>1998-11-01</p> <p>The objective of this report is to provide an overview of the petroleum geology of Canada`s west coast <span class="hlt">basins</span> and to present quantitative estimates of the oil and gas resources contained in those <span class="hlt">basins</span>. Based on geographic and tectonic considerations, the <span class="hlt">basins</span> and sub-<span class="hlt">basins</span> were grouped into three general assessment regions: Queen Charlotte, Georgia, and Tofino. The oil and gas potential is calculated using a subjective assessment technique termed conceptual play analysis, which assumes that the individual sizes of pools in a properly defined play form a natural geological population and that the distribution of pool sizes within that population is log-normal. The pool size distribution is then combined with an additional distribution describing the number of prospects and the marginal probabilities of risk factors to calculate an estimate of both play potential and individual undiscovered pool sizes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70034748','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70034748"><span><span class="hlt">Sedimentary</span> <span class="hlt">basin</span> effects in Seattle, Washington: Ground-motion observations and 3D simulations</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Frankel, Arthur; Stephenson, William; Carver, David</p> <p>2009-01-01</p> <p>Seismograms of local earthquakes recorded in Seattle exhibit surface waves in the Seattle <span class="hlt">basin</span> and <span class="hlt">basin</span>-edge focusing of S waves. Spectral ratios of Swaves and later arrivals at 1 Hz for stiff-soil sites in the Seattle <span class="hlt">basin</span> show a dependence on the direction to the earthquake, with earthquakes to the south and southwest producing higher average amplification. Earthquakes to the southwest typically produce larger <span class="hlt">basin</span> surface waves relative to S waves than earthquakes to the north and northwest, probably because of the velocity contrast across the Seattle fault along the southern margin of the Seattle <span class="hlt">basin</span>. S to P conversions are observed for some events and are likely converted at the bottom of the Seattle <span class="hlt">basin</span>. We model five earthquakes, including the M 6.8 Nisqually earthquake, using 3D finite-difference simulations accurate up to 1 Hz. The simulations reproduce the observed dependence of amplification on the direction to the earthquake. The simulations generally match the timing and character of <span class="hlt">basin</span> surface waves observed for many events. The 3D simulation for the Nisqually earth-quake produces focusing of S waves along the southern margin of the Seattle <span class="hlt">basin</span> near the area in west Seattle that experienced increased chimney damage from the earthquake, similar to the results of the higher-frequency 2D simulation reported by Stephenson et al. (2006). Waveforms from the 3D simulations show reasonable agreement with the data at low frequencies (0.2-0.4 Hz) for the Nisqually earthquake and an M 4.8 deep earthquake west of Seattle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..11.5967P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..11.5967P"><span>Geodynamical and Geochemical Features of Oil Generation in <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span> of Volga-Ural Region</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Plotnikova, I.</p> <p>2009-04-01</p> <p>Oil and gas prospects of Paleozoic <span class="hlt">sedimentary</span> rocks of Volga-Ural Anticline (VUA) various researchers evaluate in different ways. More than 150 oil fields in Paleozoic formations were discovered in the eastern half of Republic of Tatarstan of the East European Platform. There were not found any significant fields in the western areas of investigation region. According to many investigators, the western part of the Tatarstan has unfavourable geological structure from oil and gas potential view. Solution of problem concerning revealing HC source for the fields of Volga-Ural oil and gas province certainly would alow to discuss about further prospects of this territory. Data available evidence that during Paleozoic time, an area of the present-day South-Tatarian Arch (STA) and North-Tatarian Arch was a passive continental margin along which a sediments rocks up to 2 km thick was accumulated. Generation potential of organic matter containing in increased concentrations in domanikoid deposits was obtained. It has been discovered that the cumulative production in some oil areas of the Romashkino oil field substantially exceeds formerly proven, recoverable, reserves. Moreover, the volume of oil produced has already significantly exceeded the amount of oil that the Domanik strata could have generated as supposed source rocks of the South Tatarstan arch and the adjacent areas. Cumulative oil production in Tatarstan has already reached 3.0B tons, thus substantially exceeding 709M tons, calculated geochemically on the basis of the Paleozoic source rock potentials of all <span class="hlt">sedimentary</span> strata. This discrepancy obviously shows the impossibility for the commercial amounts of hydrocarbons of being generated from the available material of the <span class="hlt">sedimentary</span> cover. Some experts explain this phenomenon by the errors made in the reserve estimates. But another consider this as the inflow or replenishment by the hydrocarbon flow from the crystalline basement along the faults. Who is right</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940030921','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940030921"><span>Effects due to overlapping <span class="hlt">large</span> impact <span class="hlt">basins</span> on Mars</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Frey, Herbert; Reidy, Anne Marie; Roark, James H.; Stockman, Stephanie</p> <p>1994-01-01</p> <p>Many ancient, highly degraded <span class="hlt">large</span> impact <span class="hlt">basins</span> exist on Mars. In many cases these <span class="hlt">basins</span> overlap or are overlapped by more easily observed, presumably younger, impact <span class="hlt">basins</span>. While impact <span class="hlt">basin</span> overlap is becoming more recognized, the effects of such overlap have only occassionally been described. Such effects will depend on a variety of factors including the absolute and relative size of the <span class="hlt">basins</span>, the degree of overlap, the state of the lithosphere and its thermal gradient at the time of impact, and the time between impacts. There now exists enough evidence for overlapping <span class="hlt">basins</span> of different sizes that some of these can be discussed. This paper highlights some examples of the obvious effects of <span class="hlt">basin</span> overlap.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUSMMA11A..03N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUSMMA11A..03N"><span>Finite element modeling of hydrothermal fluid flow in Peace River Arch of Western Canada <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span>: implications for dolomitization</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Niu, Y.; Yang, J.</p> <p>2009-05-01</p> <p>A finite element computer modeling approach, integrated with existing geological, geochemical and geophysical data, was used to address the diagenetic process of dolomitization in Western Canada <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span> (WCSB). A 2-D conceptualized model was developed to simulate hydrothermal flow in particular for the packland play type dolomitization in Peace River Arch of WCSB. Our numerical results indicate that faults serve as important pathways for the ascending hydrothermal fluids driven by buoyancy force due to temporal and spatial changes in temperature. Both steady state and transient computations were conducted to reveal suitable hydraulic conditions under which the modeled temperature within the aquifer system is consistent with observed values in the targeted study area. A series of numerical case studies were carried out to investigate key factors controlling hydrothermal fluid flow, including fault penetration depth, width and permeability, and its connectivity with the host rock units.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016IJEaS.tmp..107H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016IJEaS.tmp..107H"><span>Porous media of the Red River Formation, Williston <span class="hlt">Basin</span>, North Dakota: a possible <span class="hlt">Sedimentary</span> Enhanced Geothermal System</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hartig, Caitlin M.</p> <p>2016-09-01</p> <p>Fracture-stimulated enhanced geothermal systems (EGS) can be developed in both crystalline rocks and <span class="hlt">sedimentary</span> <span class="hlt">basins</span>. The Red River Formation (Ordovician) is a viable site for development of a <span class="hlt">sedimentary</span> EGS (SEGS) because the formation temperatures exceed 140 °C and the permeability is 0.1-38 mD; fracture stimulation can be utilized to improve permeability. The spatial variations of the properties of the Red River Formation were analyzed across the study area in order to understand the distribution of subsurface formation temperatures. Maps of the properties of the Red River Formation-including depth to the top of the formation, depth to the bottom of the formation, porosity, geothermal gradient, heat flow, and temperature-were produced by the Kriging interpolation method in ArcGIS. In the future, these results may be utilized to create a reservoir simulation model of an SEGS in the Red River Formation; the purpose of this model would be to ascertain the thermal response of the reservoir to fracture stimulation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.2066R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.2066R"><span>Synthesis of Late Cretaceous-Quaternary tectonic, <span class="hlt">sedimentary</span> and magmatic processes and <span class="hlt">basin</span> formation related to episodic subduction-collision in the easternmost Mediterranean region</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Robertson, Alastair; Kinnaird, Timothy; McCay, Gillian; Palamakumbura, Romesh; Taslı, Kemal</p> <p>2015-04-01</p> <p>Mesozoic oceanic crust of the easternmost Mediterranean has experienced northwards subduction during Late Cretaceous-Cenozoic, either continuously or discontinuously based on kinematic evidence. Much of the existing information on sedimentation within the easternmost Mediterranean oceanic <span class="hlt">basin</span> comes from the non-emplaced continental margins of the Levant and North Africa. In addition, <span class="hlt">sedimentary</span> <span class="hlt">basins</span> related to plate convergence are recorded along the northern margin of the Southern Neotethyan ocean, mainly in the Kyrenia Range of northern Cyprus and its extension into the Misis Mountains of southern Turkey, coupled with the adjacent submerged areas. In a setting of only incipient continental collision such as the easternmost Mediterranean the <span class="hlt">sedimentary</span> <span class="hlt">basins</span> would be expected to remain entirely submarine. In contrast, the Kyrenia Range has been strongly uplifted and subaerially exposed during Late Pliocene-Quaternary time. This allows the recognition of a number of discrete phases of <span class="hlt">sedimentary</span> <span class="hlt">basin</span> formation: 1. Late Cretaceous (Campanian-Maastrichtian): silicic volcanism to create a subaqueous volcaniclastic apron; 2. Maastrichtian-Paleocene: pelagic carbonate deposition interspersed with proximal gravity flows and within-plate type alkaline volcanics; 3. Early Eocene: <span class="hlt">large</span>-scale <span class="hlt">sedimentary</span> melange (olistostrome) emplacement; 4. Late Eocene-Late Miocene: terrigenous gravity-flow deposition in a deep-water fault dissected 'fore arc' setting. Initial, Late Eocene non-marine coarse clastic alluvial fan deposition was succeeded by Oligocene-Miocene deep-marine siliciclastic gravity flow deposits, fining and shallowing upwards during the Late Miocene; 5. Messinian: localised precipitation of evaporites in small fault-controlled <span class="hlt">basins</span>; 6. Pliocene: shallow-marine siliciclastic-carbonate deposition in a shelf-depth, overall regressive setting; 7. Latest Pliocene to mid-Pleistocene: gravitational accumulation of coarse talus along a strongly uplifting</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMGC53C1222B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMGC53C1222B"><span>The Efficacy and Potential of Renewable Energy from Carbon Dioxide that is Sequestered in <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span> Geothermal Resources</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bielicki, J. M.; Adams, B. M.; Choi, H.; Saar, M. O.; Taff, S. J.; Jamiyansuren, B.; Buscheck, T. A.; Ogland-Hand, J.</p> <p>2015-12-01</p> <p>Mitigating climate change requires increasing the amount of electricity that is generated from renewable energy technologies and while simultaneously reducing the amount of carbon dioxide (CO2) that is emitted to the atmosphere from present energy and industrial facilities. We investigated the efficacy of generating electricity using renewable geothermal heat that is extracted by CO2 that is sequestered in <span class="hlt">sedimentary</span> <span class="hlt">basins</span>. To determine the efficacy of CO2-Geothermal power production in the United States, we conducted a geospatial resource assessment of the combination of subsurface CO2 storage capacity and heat flow in <span class="hlt">sedimentary</span> <span class="hlt">basins</span> and developed an integrated systems model that combines reservoir modeling with power plant modeling and economic costs. The geospatial resource assessment estimates the potential resource base for CO2-Geothermal power plants, and the integrated systems model estimates the physical (e.g., net power) and economic (e.g., levelized cost of electricity, capital cost) performance of an individual CO2-Geothermal power plant for a range of reservoir characteristics (permeability, depth, geothermal temperature gradient). Using coupled inverted five-spot injection patterns that are common in CO2-enhanced oil recovery operations, we determined the well pattern size that best leveraged physical and economic economies of scale for the integrated system. Our results indicate that CO2-Geothermal plants can be cost-effectively deployed in a much larger region of the United States than typical approaches to geothermal electricity production. These cost-effective CO2-Geothermal electricity facilities can also be capacity-competitive with many existing baseload and renewable energy technologies over a range of reservoir parameters. For example, our results suggest that, given the right combination of reservoir parameters, LCOEs can be as low as $25/MWh and capacities can be as high as a few hundred MW.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JAESc.114..611L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JAESc.114..611L"><span>Late Jurassic to Early Cretaceous <span class="hlt">sedimentary</span>-tectonic development in the Chengde <span class="hlt">Basin</span>, Yanshan fold-thrust belt, North China Craton</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Jian; Zhao, Yue; Liu, Ankun; Ye, Hao</p> <p>2015-12-01</p> <p>The Chengde <span class="hlt">Basin</span> is located in the central part of the Yanshan fold-thrust belt in the northern North China Craton. The sediments in the Upper Jurassic to Lower Cretaceous Tuchengzi Formation in the Chengde <span class="hlt">Basin</span> provide a detrital record of <span class="hlt">basin</span> dynamics and uplift of the <span class="hlt">basin</span> margins during that time. We analyzed the <span class="hlt">sedimentary</span> facies, paleocurrents, and provenance of the Tuchengzi Formation in the Chengde <span class="hlt">Basin</span> for the period of the Late Jurassic and Early Cretaceous shortening in the Yanshan fold-thrust belt. Four <span class="hlt">sedimentary</span> facies associations have been identified in the Tuchengzi Formation, corresponding to proximal fan, mid-fan, distal alluvial fan, and fluvial facies. The transport and distribution of the Upper Jurassic to Lower Cretaceous sediments in the Chengde <span class="hlt">Basin</span> was controlled by the faults bounding the <span class="hlt">basin</span>. Paleocurrent indicators and provenance data of conglomerate clasts reveal that the sediments of the Tuchengzi Formation in the northern part of the Chengde <span class="hlt">Basin</span> were delivered from source regions to the north of the <span class="hlt">basin</span>. The early sediments of the Tuchengzi Formation in the southern part of the <span class="hlt">basin</span> comprise a suite of fluvial deposits, similar to the fluvial sediments in the northern part of the <span class="hlt">basin</span>, and their paleocurrent data and the compositions of conglomerate clasts also suggest a northern source. However, the subsequent sedimentation in the Tuchengzi Formation in the southern part of the <span class="hlt">basin</span> changed markedly to proximal fan facies, with sediments being derived from the south of the <span class="hlt">basin</span>, according to the paleocurrent data and conglomerate clast lithology. The Sandaohe sheet, which is located in the southeast limb of the Chengde syncline, is not a klippe formed as a result of long-distance northward thrusting, but an autochthonous pop-up tectonic wedge generated by N-S shortening during the Early Cretaceous sedimentation of the Tuchengzi Formation. The sedimentation ended before the onset of the Early Cretaceous volcanic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1611152P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1611152P"><span>Geological and geochemical characteristics of <span class="hlt">sedimentary</span> rocks in Kremna, <span class="hlt">basin</span> (Serbia)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Perunović, Tamara; Jovančićević, Branimir; Brčeski, Ilija; Šajnović, Aleksandra; Stojanović, Ksenija; Simić, Vlada; Kašanin-Grubin, Milica</p> <p>2014-05-01</p> <p>Studying lacustrine sediments is important because of their potential economic value since they often bear coal, oil shales and non-metallic mineral raw materials. Besides this, lacustrine sediments offer valuable information on the climate conditions which existed during the sedimentation. In Serbia there are 14 lacustrine <span class="hlt">basins</span> spanning in age from Oligocene to Lower Pliocene. The aim of this study was to examine Lower Miocene Kremna <span class="hlt">basin</span>, located in southwest Serbia. Kremna <span class="hlt">basin</span> is a small <span class="hlt">basin</span>, covering 15km2, but sedimentologically very interesting. For the purpose of this study, 43 sediment samples were taken from a borehole at different depths, from surface to 343 m depth of the <span class="hlt">basin</span>. The borehole ended in weathered serpentinite. Mineralogical composition of sediments was determined using thin-sections and X-ray diffraction analysis, contents of macro-and microelements and rare-earth elements were determined by ICP-ES and ICP-MS techniques. Also, elemental analysis was applied to determine the contents of carbon, sulphur and nitrogen and n-alkanes, isoprenoide aliphatic alkanes and bitumen were also determined using GC-MS technique. Mineralogical analyses proved presents of several lithological types in Kremna <span class="hlt">basin</span>: clastic sediments, tuffs, tuffaceous sediments, marlstones, dolomites, magnezites, and coal of non-economic value. Occurrence of sirlezite and sepiolite was also determined. Furthermore, according to all obtained results two faciae were determined: alluvial-marginal lacustrine and intrabasinal. Alluvial-marginal facies originated from predominantly ultramafic rocks which underlie the <span class="hlt">basin</span>. Magnezites and Mg-marls and Mg-dolomites are dominant sediments in this facies. These sediments formed under arid, slightly saline conditions. Intrabasinal facies is represented mostly with marls, Mg-marls and dolomitic limestones. These sediments were deposited under a more humid climate with increase in paleoproductivity. The uppermost sediments of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6998353','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6998353"><span>The application of fossil resin biomarkers to oil-source correlation in some Australian <span class="hlt">sedimentary</span> <span class="hlt">basins</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Alexander, R.; Larcher, A.V.; Kagi, R.I. ); Price, P.L. )</p> <p>1989-03-01</p> <p>Suites of aromatic and saturated compounds which are indicative of plant resins from Araucariaceae have been identified in widely distributed sediments of Jurassic age from the Eromanga <span class="hlt">Basin</span>. Similar biomarker assemblages have been shown not to be present in sediments of Permian age from the Cooper <span class="hlt">Basin</span>. Some crude oils contained in reservoirs of Jurassic to Cretaceous age have been shown to contain the biomarker assemblage characteristic of the sediments of Jurassic age and, therefore, appear to have been derived from sediments within the Eromanga <span class="hlt">Basin</span>. Other crude oils in reservoirs of this age, together with all crude oils from reservoirs of Permian age do not contain the biomarker signature of the sediments of Jurassic age, and are therefore presumed to have been derived from the Permian sediments within the Eromanga <span class="hlt">Basin</span>. Other crude oils in reservoirs of this age, together with all crude oils from reservoirs of Permian age do not contain the biomarker signature of the sediments of Jurassic age, and are therefore presumed to have been derived from the Permian sediments of the Cooper <span class="hlt">Basin</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JVGR..308..158K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JVGR..308..158K"><span>Volcano-<span class="hlt">sedimentary</span> characteristics in the Abu Treifiya <span class="hlt">Basin</span>, Cairo-Suez District, Egypt: Example of dynamics and fluidization over <span class="hlt">sedimentary</span> and volcaniclastic beds by emplacement of syn-volcanic basaltic rocks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Khalaf, E. A.; Abdel Motelib, A.; Hammed, M. S.; El Manawi, A. H.</p> <p>2015-12-01</p> <p>This paper describes the Neogene lava-sediment mingling from the Abu Treifiya <span class="hlt">Basin</span>, Cairo-Suez district, Egypt. The lava-sediment interactions as peperites have been identified for the first time at the study area and can be used as paleoenvironmental indicators. The identification of peperite reflects contemporaneous time relationship between volcanism and sedimentation and this finding is of primary importance to address the evolutional reconstruction of the Abu Treifiya <span class="hlt">Basin</span>. Characterization of the facies architecture and textural framework of peperites was carried out through detailed description and interpretation of their outcrops. The peperites and <span class="hlt">sedimentary</span> rocks are up to 350 m thick and form a distinct stratigraphic framework of diverse lithology that is widespread over several kilometers at the study area. Lateral and vertical facies of the peperites vary from sediment intercalated with the extrusive/intrusive basaltic rocks forming peperitic breccias to lava-sediment contacts at a <span class="hlt">large</span> to small scales, respectively. Peperites encompass five main facies types ascribed to: (i) carbonate sediments-hosted fluidal and blocky peperites, (ii) lava flow-hosted blocky peperites, (iii) volcaniclastics-hosted fluidal and blocky peperites, (iv) sandstone/siltstone rocks-hosted blocky peperites, and (iv) debris-flows-hosted blocky peperites. Soft sediment deformation structures, vesiculated sediments, sediments filled-vesicles, and fractures in lava flows indicate that lava flows mingled with unconsolidated wet sediments. All the peperites in this study could be described as blocky or fluidal, but mixtures of different clast shapes occur regardless of the host sediment. The presence of fluidal and blocky juvenile clasts elucidates different eruptive styles, reflecting a ductile and brittle fragmentation. The gradual variation from fluidal to blocky peperite texture, producing the vertical grading is affected by influencing factors, e.g., the viscosity, magma</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUSM.U24A..01G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUSM.U24A..01G"><span>The Role of Groundwater Flow and Faulting on Hydrothermal Ore Formation in <span class="hlt">Sedimentary</span> <span class="hlt">Basins</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Garven, G.</p> <p>2006-05-01</p> <p>Sediment-hosted ore formation is thought to occur as a normal outcome of <span class="hlt">basin</span> evolution, due to deep groundwater flow, heat transport, and reactive mass transport ---all of which are intimately coupled. This paper reviews recent attempts to understand the hydrologic and geochemical processes forming some of the world's largest sediment-hosted ores. Several questions still dominate the literature (driving forces for flows, source and controls on metal acquisition, concentrations of ore-forming components, timing and duration, role of faults, effects of transient flows). This paper touches upon all of these questions. Coupled reactive transport models have been applied for understanding the genesis of sandstone-hosted uranium ores of North America and Australia, red-bed copper ores of North America and northern Europe, carbonate-hosted MVT lead-zinc ores of the U.S. Midcontinent and northwestern Canada, and the carbonate- hosted lead-zinc ores of Ireland and southeast France. Good progress has been made in using these computational methods for comparing and contrasting both carbonate hosted (MVT and Irish types) and shale- hosted (SEDEX type) Pb-Zn deposits. The former are mostly associated with undeformed carbonate platforms associated with distal orogenic belts and the later are mostly associated with extensional <span class="hlt">basins</span> and failed rifts that are heavily faulted. Two giant ore provinces in extensional <span class="hlt">basins</span> provide good examples of structural control on reactive mass transport: shale-hosted Pb-Zn ores of the Proterozoic McArthur <span class="hlt">basin</span>, Australia, and shale-hosted Pb-Zn-Ba ores of the Paleozoic Kuna <span class="hlt">basin</span>, Alaska. For the McArthur <span class="hlt">basin</span>, hydrogeologic simulations of thermally-driven free convection suggest a strong structural control on fluid flow created by the north-trending fault systems that dominate this Proterozoic extensional <span class="hlt">basin</span>. Brines appear to have descended to depths of a few kilometers along the western side of the <span class="hlt">basin</span>, migrated laterally to the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014Tectp.635....6B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014Tectp.635....6B"><span>Late Cretaceous to Late Eocene Hekimhan <span class="hlt">Basin</span> (Central Eastern Turkey) as a supra-ophiolite <span class="hlt">sedimentary</span>/magmatic <span class="hlt">basin</span> related to the later stages of closure of Neotethys</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Booth, Matthew G.; Robertson, Alastair H. F.; Tasli, Kemal; İnan, Nurdan</p> <p>2014-11-01</p> <p>The Hekimhan <span class="hlt">Basin</span> is here put forward as a type example of a globally important class of <span class="hlt">basin</span>, known as a supra-ophiolite <span class="hlt">basin</span>. Such <span class="hlt">basins</span> form after the emplacement of ophiolitic (i.e. oceanic) rocks onto a passive continental margin, but long prior to continental collision. The Hekimhan <span class="hlt">Basin</span> developed as part of the northern margin of the Tauride microcontinent during the collision and suturing of two Neotethyan oceans to the north, namely the Inner Tauride Ocean and the İzmir-Ankara-Erzincan ocean. The <span class="hlt">basin</span> records two main stages of tectonic development, during latest Cretaceous to Late Eocene time. The first phase of <span class="hlt">basin</span> development during the Late Cretaceous (Maastrichtian) began with the erosion of emplaced ophiolitic rocks, resulting in non-marine clastic sedimentation. Subsequently, the <span class="hlt">basin</span> rapidly subsided, in response to inferred regional crustal extension, resulting in the deposition of hemipelagic marls and local sapropelic mudstones. The axial parts of the <span class="hlt">basin</span> experienced alkaline, within-plate-type, basaltic volcanism. The Late Maastrichtian culminated in deposition of shallow-marine carbonates. Overlying Paleocene sediments are restricted to thin, localised, marine evaporates, associated with a low-angle unconformity. The second stage of <span class="hlt">basin</span> development began during the Early Eocene with deposition of shallow-marine carbonates, coupled with localised basaltic volcanism, again of extensional type. The <span class="hlt">basin</span> emerged during the Mid-Late Eocene in a late-stage collisional to post-collisional setting. Compressional deformation <span class="hlt">largely</span> reflects post-suture tightening. A short-lived marine transgression occurred during the Mid-Miocene. The <span class="hlt">basin</span> was later deformed by both left-lateral and right-lateral strike-slip. Several different tectonic models are considered, notably extension related to the northward pull of a still-subducting oceanic slab, and back-arc extension related to northward subduction of Neotethys (to the south). The first</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/769000','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/769000"><span>Canyon drainage induced mixing over a <span class="hlt">large</span> <span class="hlt">basin</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Stalker, J.</p> <p>2000-05-01</p> <p>Complex terrain surrounding urbanized <span class="hlt">basins</span> around the world has long been recognized to strongly affect the characteristics of vertical transport and mixing of pollutants. The Department of Energy's Vertical Transport and Mixing (VTMX) program will investigate mixing processes within night-time boundary layers over <span class="hlt">large</span> urban <span class="hlt">basins</span>. The program will launch several field experiments within the Salt Lake City <span class="hlt">basin</span> in the coming years. This modeling study, like many other studies being undertaken by the participants of the VTMX programs, is intended to complement the proposed field experiments by numerically examining some of the flow interactions known to occur in <span class="hlt">large</span> <span class="hlt">basins</span>. Using idealized simulations, we particularly investigate drainage flows from deep canyons similar to those along the Wasatch Front into the Salt Lake City <span class="hlt">basin</span>. Literature shows that under favorable conditions, drainage flows can generate bore waves that may propagate ahead of the density current (e.g., Simpson 1969; Simpson 1982; Crook and Miller 1985). Existence and frequency of such bore waves can profoundly influence the spatial and temporal variability of vertical transport and mixing within <span class="hlt">large</span> <span class="hlt">basins</span>. If bore waves do occur on a regular basis within the Salt Lake City <span class="hlt">basin</span> (a task for the upcoming experiments to determine), then understanding the <span class="hlt">basin</span>-scale conditions under which these waves are produced and how they may propagate and interact with the city's buildings will be of great importance in characterizing transport and mixing processes within the <span class="hlt">basin</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMEP51D3556B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMEP51D3556B"><span>Andean <span class="hlt">Basins</span> Morphometry: Assesing South American <span class="hlt">Large</span> Rivers' Source Areas</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bean, R. A.; Latrubesse, E. M.</p> <p>2014-12-01</p> <p>Presently there are no regional-scale morphometric analyses of Andean fluvial <span class="hlt">basins</span>. Therefore, we created a continental-scale database of these <span class="hlt">basins</span>. Our data covers over an area 1,000,000 km2 of the Andes, from Venezuela to Argentina. These <span class="hlt">basins</span> are the source of some of the largest rivers in the world including the Amazon, Orinoco, Parana, and Magdalena. Morphometric parameters including shape factor, relief ratio, longitudinal profiles and different indices of <span class="hlt">basin</span> elevation were calculated based on the CGIAR SRTM 4.1 DEM (~90 m resolution). FAO Hydrosheds were used to segment the DEM by major catchment and then manually cut at the Andean zone. In the North and Central Andes, this produced over 500,000 subcatchments, which we reduced to 619 by setting minimum catchment area to 100 km2. We then integrate lithologic data from DNPM geologic data. Our results indicate that <span class="hlt">sedimentary</span> lithologies dominate Central Andean catchments (n=268,k=4), which cover an area 767,00 km2, while the Northern Andean catchments (covering 350,000 km2) are more varied, dominated by volcanics in the Pacific (n=78), a <span class="hlt">sedimentary</span> (48%) dominant mix in the Caribbean (n=138) and 60% <span class="hlt">sedimentary</span> in the Amazon-Orinoco subregion catchments (n=138). Elevation averages are smallest in the north Andes and average maximum elevations (6,026 m) in the Argentinian catchments (n=65) of the Central Andes are the highest. Shape factors range from 0.49 to 0.58 in the North and 0.52 to 0.58 in the Central Andes. There are clear differences in all categories between region and subregion, but that difference does not hinge on a single morphometric or geologic parameter. Morphometric parameters at a watershed scale (listed in Table) are analyzed and hydrologic data from gauging stations throughout the Andes (n=100) are used to compare morphometric parameters with lithology and characteristics from the <span class="hlt">basin</span> hydrograph (peak discharge timing, minimum and maximum discharge, and runoff).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11179715','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11179715"><span>Permian, Jurassic and Early Cretaceous palynofloral assemblages from subsurface <span class="hlt">sedimentary</span> rocks in Chuperbhita Coalfield, Rajmahal <span class="hlt">Basin</span>, India.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tripathi, A</p> <p>2001-04-01</p> <p>The results of a palynological analysis of the <span class="hlt">sedimentary</span> sequence of Borehole RCH-151, Chuperbhita Coalfield, Rajmahal <span class="hlt">Basin</span>, Bihar are presented here. The borehole penetrated the Rajmahal Formation (comprising two traps sandwiching an intertrappean bed), the thinly represented Dubrajpur Formation and in its lower part, the Coal Measures. The coal-bearing interval is associated with Scheuringipollenites barakarensis, Faunipollenites varius, Densipollenites indicus, Gondisporites raniganjensis and Densipollenites magnicorpus Assemblage Zones. The presence of these biostratigraphic units indicates correlation with the Barakar Formation (Early Permian) and the Barren Measures and Raniganj Formations (both Late Permian). This is the first record, in the Chuperbhita Coalfield, of Late Permian strata, which appear to represent a condensed sequence. Prior to the present study, the Permian succession was thought to have been associated entirely with the Barakar Formation. The overlying Dubrajpur Formation yielded a distinct spore-pollen assemblage (in association with the first report of dinoflagellate, Phallocysta), which is assigned to the newly identified Callialasporites turbatus palynozone of latest Early to early Middle Jurassic age. The diverse spore-pollen flora of the intertrappean bed (Rajmahal Formation) incorporates several age marker taxa, viz. Undulatisporites, Leptolepidites, Klukisporites, Ruffordiaspora, and Coptospora. The assemblages from intertrappean beds are correlated with the Ruffordiaspora australiensis palynozone of Australia. Thus the palynodating indicates Permian, latest Early to early Mid-Jurassic and Early Cretaceous age for the strata studied. This is the first record of definite Jurassic microfossils from the non-marine sequence of Rajmahal <span class="hlt">Basin</span>, India.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1188944','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1188944"><span>Impact of <span class="hlt">sedimentary</span> provenance and weathering on arsenic distribution in aquifers of the Datong <span class="hlt">basin</span>, China: Constraints from elemental geochemistry</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Xie, Xianjun; Wang, Yanxin; Ellis, Andre; Liu, Chongxuan; Duan, Mengyu; Li, Junxia</p> <p>2014-11-01</p> <p>Arsenic (As)-contaminated aquifer sediments from Datong <span class="hlt">basin</span>, China have been analyzed to infer the provenance and depositional environment related to As distribution in the aquifer sediments. The As content in the sediments ranged from 2.45 to 27.38 mg/kg with an average value of 9.54 mg/kg, which is comparable to the average value in modern unconsolidated sediments. However, minor variation in As concentration with depth has been observed in the core. There was a significant correlation between Fe, and Al and As, which was attributed to the adsorption or co-precipitation of As onto/with Fe oxides/hydroxides and/or Fe-coated clay minerals. Post-Archean Australian Shale (PAAS)-normalized REEs patterns of sediment samples along the borehole were constant, and the sediments had a notably restricted range of La-N/Yb-N ratios from 0.7 to 1.0. These results suggested that the provenance of the Datong <span class="hlt">basin</span> remained similar throughout the whole depositional period. The analysis of major geochemical compositions confirmed that all core sediments were from the same <span class="hlt">sedimentary</span> source and experienced significant <span class="hlt">sedimentary</span> recycling. The co-variation of As, V/Al, Ni/Al and chemical index of alteration (CIA) values in the sediments along the borehole suggested that As distribution in the sediments was primarily controlled by weathering processes. The calculated CIA values of the sediments along the borehole indicate that a relative strong chemical weathering occurred during the deposition of sediments at depths of similar to 35 to 88 m, which was corresponding to the depth at which high As groundwater was observed at the site. Strong chemical weathering favored the deposition of Fe-bearing minerals including poorly crystalline and crystalline Fe oxide mineral phases and concomitant co-precipitation of As with these minerals in the sediments. Subsequent reductive dissolution of As-bearing poorly crystalline and crystalline Fe oxides would result in the enrichment of As in</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JHyd..519.3541X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JHyd..519.3541X"><span>Impact of <span class="hlt">sedimentary</span> provenance and weathering on arsenic distribution in aquifers of the Datong <span class="hlt">basin</span>, China: Constraints from elemental geochemistry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xie, Xianjun; Wang, Yanxin; Ellis, Andre; Liu, Chongxuan; Duan, Mengyu; Li, Junxia</p> <p>2014-11-01</p> <p>Arsenic (As)-contaminated aquifer sediments from Datong <span class="hlt">basin</span>, China have been analyzed to infer the provenance and depositional environment related to As distribution in the aquifer sediments. The As content in the sediments ranged from 2.45 to 27.38 mg/kg with an average value of 9.54 mg/kg, which is comparable to the average value in modern unconsolidated sediments. However, minor variation in As concentration with depth has been observed in the core. There was a significant correlation between Fe, and Al and As, which was attributed to the adsorption or co-precipitation of As onto/with Fe oxides/hydroxides and/or Fe-coated clay minerals. Post-Archean Australian Shale (PAAS)-normalized REEs patterns of sediment samples along the borehole were constant, and the sediments had a notably restricted range of LaN/YbN ratios from 0.7 to 1.0. These results suggested that the provenance of the Datong <span class="hlt">basin</span> remained similar throughout the whole depositional period. The analysis of major geochemical compositions confirmed that all core sediments were from the same <span class="hlt">sedimentary</span> source and experienced significant <span class="hlt">sedimentary</span> recycling. The co-variation of As, V/Al, Ni/Al and chemical index of alteration (CIA) values in the sediments along the borehole suggested that As distribution in the sediments was primarily controlled by weathering processes. The calculated CIA values of the sediments along the borehole indicate that a relative strong chemical weathering occurred during the deposition of sediments at depths of ∼35 to 88 m, which was corresponding to the depth at which high As groundwater was observed at the site. Strong chemical weathering favored the deposition of Fe-bearing minerals including poorly crystalline and crystalline Fe oxide mineral phases and concomitant co-precipitation of As with these minerals in the sediments. Subsequent reductive dissolution of As-bearing poorly crystalline and crystalline Fe oxides would result in the enrichment of As in groundwater</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1612665F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1612665F"><span>Geothermal potential of Caledonian granites underlying Upper Palaeozoic <span class="hlt">sedimentary</span> <span class="hlt">basins</span> astride the Iapetus Suture Zone in Ireland</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fritschle, Tobias; Daly, J. Stephen; Whitehouse, Martin J.; McConnell, Brian; Buhre, Stephan</p> <p>2014-05-01</p> <p>Upper Palaeozoic <span class="hlt">sedimentary</span> <span class="hlt">basins</span> in Ireland overlie crystalline rocks within the Caledonian Iapetus Suture Zone. Beneath these <span class="hlt">basins</span>, Lower Palaeozoic rocks, formed and deformed during the Caledonian orogenic cycle, were intruded by c. 420-390 Ma late-tectonic granites at various tectonic levels. These include the subsurface Kentstown and Glenamaddy granites discovered by mineral exploration drilling. While these granites comprise actual targets for Enhanced Geothermal System (EGS) exploration, several others likely exist based on geophysical considerations. In order to test the regional geothermal potential, the buried granites as well as analogue exposed rocks are being investigated geochemically. The geothermal potential of the intrusives depends on their heat production rate (HPR), which is calculated using rock density and concentrations of the heat producing elements (HPE) uranium, thorium and potassium. In spite of their close spacing and similar ages, the whole-rock geochemistry of the granites varies significantly, but with no obvious geographical control (Fritschle et al., 2013; 2014). The granite HPR values range from 1.4 μW/m3 for the Dhoon Granite (Isle of Man) to 4.9 μW/m3 for the Drogheda Granite (Ireland). This compares with the average HPR for a 'typical' granite of 2.7 μW/m3 (Goldstein et al., 2009). It is demonstrated that an elevated HPR of a granite can be related to enrichment in one of the HPE alone (e.g., uranium-enrichment in the Foxdale Granite (Isle of Man), or thorium-enrichment in the Drogheda Granite). Enrichment in HPE in a granite may occur due to different reasons including hydrothermal (re-) distribution of uranium, or the assimilation of thorium-rich wall-rocks. Hence, the distribution of the HPE in particular minerals, veins and source lithologies, along with the petrophysical characteristics of the <span class="hlt">sedimentary</span> <span class="hlt">basins</span> and the granites' petrogenesis, are currently being investigated as possible mechanisms controlling their</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1992SedG...78..155D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1992SedG...78..155D"><span>Oxygen-isotope evidence for upward, cross-formational porewater flow in a <span class="hlt">sedimentary</span> <span class="hlt">basin</span> near maximum burial</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>de Caritat, Patrice; Baker, Julian C.</p> <p>1992-07-01</p> <p>Authigenic ankerite in the gas-bearing mid-Permian Aldebaran Sandstone (Denison Trough, Queensland, Australia) has an anomalously light oxygen-isotopic composition ( δ 18O SMOW range: +7.6 to +14.4‰ ) and exhibits a trend of 18O-enrichment from the base to the top of the unit. Textural relationships, together with burial and thermal modelling, indicate that this carbonate precipitated at temperatures of about 100 to 140°C, when the sequence approached maximum burial during the Late Triassic. This implies that ankerite precipitated from porewater very depleted in 18O with respect to marine water ( δ 18O SMOW = -9 to -5‰ ). The formation of this deep, relatively high-temperature ankerite is difficult to reconcile with downward percolation of meteoric water at that time since the <span class="hlt">basin</span> was then undergoing its first burial/compactional cycle. We interpret the ankerite to have precipitated from porewater expelled upward from the earliest Permian Reids Dome beds. This thick unit, consisting mainly of high-latitude continental sandstones, mudrocks and coals, was initially saturated with very 18O-depleted meteoric water ( δ 18O SMOW ≈ -17‰ ) partly derived from melted snow and ice, and is likely to have undergone overpressuring during rapid burial (at rates up to 1 km/Ma). Tectonically induced expulsion of "connate meteoric" porewater out of the Reids Dome beds took place as the sequence approached maximum burial prior to Late Triassic <span class="hlt">basin</span> uplift. This water was flushed upward through the overlying units, retaining a (modified) meteoric isotopic signature, which was recorded by the precipitating ankerite. Computer modelling of heat transport, isotopic mass balance and water mixing quantitatively shows that this interpretation is viable, lending support to the suggested mechanism of upward, cross-formational porewater flow deep in a <span class="hlt">sedimentary</span> <span class="hlt">basin</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AGUSM.T43B..08S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AGUSM.T43B..08S"><span>Processes in Environmental Depositional Systems and Deformation in <span class="hlt">Sedimentary</span> <span class="hlt">Basins</span>: Goals for Exoloration in Mexico</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sandoval-Ochoa, J.</p> <p>2005-05-01</p> <p>Among the recent needs to establish new goals in the mexican energy industry to increase the petroleum reserves, has been necessary to recapitulate on some academic an operative concepts and definitions applied to the Petroliferous <span class="hlt">Basins</span> Exploration; first of all, in order to understand the Petroleum System in given tectonophysical framework. The tectonophysical environment experienced by the petroliferous <span class="hlt">basin</span> in the southwestern Gulf of Mexico, merely in the Campeche Sound and adjacent terrestrial regions (Figure 1); has been the result of interaction among the tectonic plates, the Coco's Plate with impingement and subduction beneath the Northamerican Plate and the Yucatán Microplate and even in very deep connection with the oceanic crust of southwesternmost portion of the Gulf of Mexico and the one of the Caribbean sea beneath the gulf of Belize-Honduras. The tectonosedimentary effects in the Campeche Bay starting with the skeleton formed for the Cenozoic Era, kept simultaneous conditions in depositions and deformations because of strain, stress and collapse fields, acted through this Era up to the present day, as observed in the surface Aguayo et al, 1999 and Sandoval, 2000. The involved portions of the crust and its boundaries have also been performing the relative sinking of the mere southwestern centre of the Gulf of Mexico, and the rising of the southeastern lands of Mexico. In the middle contiguity are found the productive Tertiary <span class="hlt">basins</span> of: Comalcalco, Macuspana, Salina del Itsmo, Campeche-Champoton and other in deep waters; all of them, in an arrangement of <span class="hlt">basins</span> among distensive faulted blocks in echelon, falling down to the deep centre of the Gulf Sandoval, op cit. With this scenario and that ones of other <span class="hlt">basins</span>, a recapitulation on concepts and definitions, has been made on the regional natural processes of the environmental depositional systems and on the <span class="hlt">basins</span> analysis in the tectonophysical framework, in order to reflect on the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19860021656','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19860021656"><span>Potassium metasomatism of volcanic and <span class="hlt">sedimentary</span> rocks in rift <span class="hlt">basins</span>, calderas and detachment terranes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chapin, C. E.; drographic basins.</p> <p>1985-01-01</p> <p>The chemical, mineralogical, and oxygen-isotopic changes accompanying K-metasomatism are described. The similarities with diagenetic reactions in both deep marine and alkaline, saline-lake environments are noted. The common occurrence of K-metasomatism in upper-plate rocks of detachment terranes indicates that the early stage of severe regional extension causes crustal downwarping and, in arid to semi-arid regions, development of closed hydrographic <span class="hlt">basins</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhDT.......148C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhDT.......148C"><span>Evaluating <span class="hlt">sedimentary</span> <span class="hlt">basins</span> for geothermal power production potential and bottom-hole temperature corrections</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Crowell, Anna M.</p> <p></p> <p>At present, the risks and costs associated with geothermal energy wildcat exploration are prohibitive. With improved technology, the future may be brighter, and a play fairway analysis, for geothermal exploration can guide development. Comparing geophysical data with geothermal gradient allows identification of potentially economic areas of interest. The play fairway analysis is a common tool used by the petroleum industry to identify areas for potential exploration. The analysis identifies areas in the Denver, Illinois, Michigan, and Williston <span class="hlt">Basins</span> with the highest development potential. A great deal of data have potential for a play fairway analysis, but data quality is problematic due to systematic errors in bottom-hole temperatures (BHTs). Corrections to bottom-hole temperatures are necessary due to the perturbation of temperature caused by the drilling mud, and can range from 5 to 30 °C. Correction schemes for bottom-hole temperatures can be applied to both the energy-in-place estimates and play fairway analyses. The Harrison equation is the most accurate for <span class="hlt">basins</span> less than 4.5 km deep. The Kehle correction is the most accurate for <span class="hlt">basins</span> deeper than 4.5 km. Chapter II explains why BHTs grouped by depth are more statistically robust than those grouped by geochronological unit. Chapter III demonstrates why the Harrison Equation is the best correction method to use for BHTs. Chapters IV and V give the volumetric energy-in-place for the Denver, Illinois, and Michigan <span class="hlt">Basins</span> for discrete temperature ranges, and Chapter 6 provides the final Play Fairway Favorability maps.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.T11B2063T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.T11B2063T"><span>Hidden Rift Structure Beneath a Thick <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span> in the Niigata Region, Japan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Takeda, T.; Enescu, B.; Asano, Y.; Obara, K.; Sekiguchi, S.</p> <p>2010-12-01</p> <p>Niigata region is located in a high-strain-rate zone, along the easternmost margin of the back-arc <span class="hlt">basin</span> of the Sea of Japan (Sagiya et al., 2000, Okamura et al., 1995). In this region, two M6.8 inland earthquakes with reverse fault type focal mechanism, having NW-SE compression, occurred in 2004 and 2007. The reverse fault system may indicate present reactivation of the rift structure formed as a result of normal faulting when the Sea of Japan opened in the Miocene (Sato, 1994). Therefore, imaging the spatial extent of the rift structure is important to reveal the seismotectonics and occurrence mechanism of inland earthquakes. To resolve the fine structure beneath the Niigata region, we have installed a dense temporary network of 300 seismic stations and performed a regional tomography analysis. The temporary seismic network was designed with a multi-scale station spacing of 3 to 5 km in and around the aftershock areas of the two <span class="hlt">large</span> earthquakes, and of ~10 km for the surrounding region. The 3D velocity tomography analysis and relocation of earthquakes were performed using the tomoDD software (Zhang and Thurber, 2003). We used 777 events that occurred after the installation of the temporary network and 703 events that were recorded only by the permanent seismic network (Hi-net) before the temporary network deployment. The initial 3D velocity model was constructed by using the 3D shallow velocity structure provided by the “Japan Seismic Hazard Information Station” (J-SHIS; Fujiwara et al., 2009) of NIED. The horizontal and vertical grid spacing were of 5 ~ 10 km and 2 ~ 4 km, respectively. The tomography analysis enabled us to delineate the fine subsurface structure. The high and low velocity pattern corresponds well to the Bouguer gravity anomalies mapped in the region. The velocity model shows a wide and relatively low velocity (< 5 km/sec for the P-wave velocity) band extending in a NE-SW direction. The band widens and narrows along its extent. The</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRE..121.2239S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRE..121.2239S"><span>A <span class="hlt">sedimentary</span> origin for intercrater plains north of the Hellas <span class="hlt">basin</span>: Implications for climate conditions and erosion rates on early Mars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Salese, Francesco; Ansan, Veronique; Mangold, Nicolas; Carter, John; Ody, Anouck; Poulet, Francois; Ori, Gian Gabriele</p> <p>2016-11-01</p> <p>Understanding the origin (volcanic or <span class="hlt">sedimentary</span>) and timing of intercrater plains is crucial for deciphering the geological evolution of Mars. We have produced a detailed geological map of the intercrater plains north of the Hellas <span class="hlt">basin</span>, based on images from the Mars Express High-Resolution Stereo Camera, the Mars Reconnaissance High-Resolution Imaging Science Experiment, and Context. Erosional windows and fresh impact craters provide a way of studying the lithology of intercrater plain units. They are composed predominantly of light-toned <span class="hlt">sedimentary</span> rocks with subhorizontal bedding over a broad extent (greater than tens of kilometers), showing cross-bedding stratifications locally. The broad extent, geometry, and flat topography of these sediments favor a formation by aqueous processes (alluvial and lacustrine) rather than airfall (eolian and volcaniclastic). The Late Noachian ( 3.7 Ga) <span class="hlt">sedimentary</span> plains are locally covered by dark-toned, rough-textured lava flows of Late Hesperian age ( 3.3 Ga). Fe/Mg phyllosilicates were detected within <span class="hlt">sedimentary</span> rocks, whereas volcanic rocks contain pyroxene and lack signatures of alteration, in agreement with interpretations made from texture and morphology. In erosional windows, the superimposition of <span class="hlt">sedimentary</span> rocks by younger volcanic flows enables the estimation of an erosion rate of 1000 nm yr-1 during the Hesperian period (3.3-3.7 Ga). Thus, our study shows that an intense <span class="hlt">sedimentary</span> cycle occurred on the northern rim of the Hellas <span class="hlt">basin</span> before and during the Late Noachian, leading to the formation of widespread <span class="hlt">sedimentary</span> plains, which were then eroded, in agreement with a gradual change in the climatic conditions in this period, and later covered by volcanic flows.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFM.H14A..01K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFM.H14A..01K"><span>Potential Environmental Impacts of CO2 Storage in <span class="hlt">Sedimentary</span> <span class="hlt">Basins</span>: Results From the Frio Brine Test, Texas, USA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kharaka, Y. K.; Cole, D. R.; Hovorka, S. D.; Phelps, T. J.; Nance, S.</p> <p>2006-12-01</p> <p>Deep saline aquifers in <span class="hlt">sedimentary</span> <span class="hlt">basins</span>, including depleted petroleum reservoirs, provide advantageous locations close to major anthropogenic sources of CO2 and potential capacity for the storage of huge volumes of this greenhouse gas. To investigate the potential for the long-term storage of CO2 in such aquifers, 1600 t of CO2 were injected at 1500 m depth into a 24-m-thick "C" sandstone section of the Frio Formation, a regional saline aquifer in the U.S. Gulf Coast. Fluid samples obtained before CO2 injection from the injection well and an observation well 30 m updip showed a Na-Ca-Cl type brine with 93,000 mg/L TDS at near saturation with CH4 at reservoir conditions; gas analyses show CH4 comprised ~95% of dissolved gas, but CO2 was low at 0.3%. Following CO2 breakthrough, 51 h after injection, samples showed sharp drops in pH (6.5 to 5.7), pronounced increases in alkalinity (100 to 3000 mg/L as HCO3) and in Fe (30 to 1100 mg/L), and significant shifts in the isotopic compositions of H2O, Sr, DIC, and CH4. These data coupled with geochemical modeling indicate rapid dissolution of minerals, especially calcite and iron oxyhydroxides caused by lowered pH (~3.0 initially) of the brine in contact with the injected supercritical CO2. These geochemical parameters, together with perfluorocarbon tracer gases (PFTs) proved effective in mapping the distribution and interactions of the injected CO2 in the Frio "C". They are being used to track the migration of the injected CO2 into the local shallow groundwater and into the overlying Frio "B", comprised of a 4-m-thick sandstone bed and separated from the "C" by ~15 m of shale, muddy sandstone and siltstone beds. Results obtained to date from the four monitoring groundwater wells perforated (26-29 m) in the Beaumont aquifer show some temporal chemical changes. These changes, however, are tentatively attributed to natural variations and recharge events caused by the construction of a mud pit at the site, and not to leakage</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950024444','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950024444"><span>Laboratory simulated hydrothermal alteration of <span class="hlt">sedimentary</span> organic matter from Guaymas <span class="hlt">Basin</span>, Gulf of California. Ph.D. Thesis</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Leif, Roald N.</p> <p>1993-01-01</p> <p>High temperature alteration of <span class="hlt">sedimentary</span> organic matter associated with marine hydrothermal systems involves complex physical and chemical processes that are not easily measured in most natural systems. Many of these processes can be evaluated indirectly by examining the geochemistry of the hydrothermal system in the laboratory. In this investigation, an experimental organic geochemical approach to studying pyrolysis of <span class="hlt">sedimentary</span> organic matter is applied to the hydrothermal system in the Guaymas <span class="hlt">Basin</span>, Gulf of California. A general survey of hydrothermal oils and extractable organic matter (bitumen) in hydrothermally altered sediments identified several homologous series of alkanones associated with a high temperature hydrothermal origin. The alkanones range in carbon number from C11 to C30 with no carbon number preference. Alkan-2-ones are in highest concentrations, with lower amounts of 3-, 4-, 5- (and higher) homologs. The alkanones appear to be pyrolysis products synthesized under extreme hydrothermal conditions. Hydrous pyrolysis and confinement pyrolysis experiments were performed to simulate thermally enhanced diagenetic and catagenetic changes in the immature <span class="hlt">sedimentary</span> organic matter. The extent of alteration was measured by monitoring the n-alkanes, acyclic isoprenoids, steroid and triterpenoid biomarkers, polycyclic aromatic hydrocarbons and alkanones. The results were compared to bitumen extracts from sediments which have been naturally altered by a sill intrusion and accompanied hydrothermal fluid flow. These pyrolysis experiments duplicated many of the organic matter transformations observed in the natural system. Full hopane and sterane maturation occurred after 48 hr in experiments at 330 deg C with low water/rock mass ratios (0.29). A variety of radical and ionic reactions are responsible for the organic compound conversions which occur under extreme hydrothermal conditions. Short duration pyrolysis experiments revealed that a portion of the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.3600M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.3600M"><span>About the Relation Between Geodynamics of the <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span> and the Properties of Crude Oil</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Muslimov, R.; Plotnikova, I.</p> <p>2012-04-01</p> <p>Earlier, we wrote and reported about the modern geodynamic activity of the territory of South-Tatar arch, where the Romashkino oil field. We identified a periodic change in flow rates of oil and oil density at Romashkino and other oil fields of the South Tatar arch. Now we have studied the composition of oils and bitumoids from uneven (in terms of age) deposites of the <span class="hlt">sedimentary</span> cover and basement rocks in the zones of possible hydrocarbon seepage in the central squares of Romashkinskoye field. The results of the comparative studies allowed us to come to the conclusion that the formation of oil-bearing deposits of Romashkinskoye field owes to the income and mixing of hydrocarbons (HC) fluids from different sources. The analysis of geological and production data (GPD) that was held during the many years of exploitation of the development wells of Romashkinskoye field by TatNIPIneft under the direction of I.F. Glumov suggests contemporary inflow of hydrocarbons in the industrial oil reservoir of the Pashi horizon of Romashkinskoye field and the existence of localized areas of inflow of new portions of HC. A number of criteria was worked out in the analysis of the GPD; that allowed us to identify among the total number of wells those, in which the process of hydrocarbon seepage was recorded with the greatest probability. Such wells were called anomalous. One of the directions of this research was to study the geochemical characteristics of oil from anomalous wells and to determine the degree of similarity and difference between this oil and the oil from both normal wells (in which the signs of deep seepage is not recorded), and bituminoid from the crystalline basement and <span class="hlt">sedimentary</span> cover. If the hypothesis of a recurrent (also in modern times) influx of deep hydrocarbon is correct, then the oil from the anomalous wells should have specific features in comparison with the wells located outside the areas of the expected inflow. The results of geochemical studies of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1994GeoRu..83..787G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1994GeoRu..83..787G"><span>Mineral deposit formation in Phanerozoic <span class="hlt">sedimentary</span> <span class="hlt">basins</span> of north-east Africa: the contribution of weathering</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Germann, Klaus; Schwarz, Torsten; Wipki, Mario</p> <p>1994-12-01</p> <p>The intra- and epicontinental <span class="hlt">basins</span> in north-east Africa (Egypt, Sudan) bear ample evidence of weathering processes repeatedly having contributed to the formation of mineral deposits throughout the Phanerozoic. The relict primary weathering mantle of Pan-African basement rocks consists of kaolinitic saprolite, laterite (in places bauxitic) and iron oxide crust. On the continent, the reaccumulation of eroded weathering-derived clay minerals (mainly kaolinite) occurred predominantly in fluvio-lacustrine environments, and floodplain and coastal plain deposits. Iron oxides, delivered from ferricretes, accumulated as oolitic ironstones in continental and marine sediments. Elements leached from weathering profiles accumulated in continental <span class="hlt">basins</span> forming silcrete and alunite or in the marine environment contributing to the formation of attapulgite/saprolite and phosphorites. The Early Paleozoic Tawiga bauxitic laterite of northern Sudan gives a unique testimony of high latitude lateritic weathering under global greenhouse conditions. It formed in close spatial and temporal vicinity to the Late Ordovician glaciation in north Africa. The record of weathering products is essentially complete for the Late Cretaceous/Early Tertiary. From the continental sources in the south to the marine sinks in the north, an almost complete line of lateritic and laterite-derived deposits of bauxitic kaolin, kaolin, iron oxides and phosphates is well documented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012HydJ...20...61O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012HydJ...20...61O"><span>Groundwater recharge to a <span class="hlt">sedimentary</span> aquifer in the topographically closed Uley South <span class="hlt">Basin</span>, South Australia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ordens, Carlos M.; Werner, Adrian D.; Post, Vincent E. A.; Hutson, John L.; Simmons, Craig T.; Irvine, Benjamin M.</p> <p>2012-02-01</p> <p>The chloride mass balance (CMB) and water-table fluctuation (WTF) analysis methods were used to estimate recharge rates in the Uley South <span class="hlt">Basin</span>, South Australia. Groundwater hydrochemistry and isotope data were used to infer the nature of recharge pathways and evapotranspiration processes. These data indicate that some combination of two plausible processes is occurring: (1) complete evaporation of rainfall occurs, and the precipitated salts are washed down and redissolved when recharge occurs, and (2) transpiration dominates over evaporation. It is surmised that sinkholes predominantly serve to by-pass the shallow soil zone and redistribute infiltration into the deeper unsaturated zone, rather than transferring rainfall directly to the water table. Chlorofluorocarbon measurements were used in approximating recharge origins to account for coastal proximity effects in the CMB method and pumping seasonality was accounted for in the WTF-based recharge estimates. Best estimates of spatially and temporally averaged recharge rates for the <span class="hlt">basin</span> are 52-63 and 47-129 mm/year from the CMB and WTF analyses, respectively. Adaptations of both the CMB and WTF analyses to account for nuances of the system were necessary, demonstrating the need for careful application of these methods.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.H33C1337N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.H33C1337N"><span>Wetland river flow interaction in a <span class="hlt">sedimentary</span> formation of the white Volta <span class="hlt">basin</span>, Ghana</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nyarko, B. K.; Diekkruger, B.; Van De Giesen, N.; Barry, B.</p> <p>2011-12-01</p> <p>Groundwater resources in the floodplain wetlands of the White Volta River <span class="hlt">basin</span> of Ghana is a major source of water for irrigation activities of communities living around and baseflow to sustain the flow of the river. Hydrology of the floodplain wetlands in the <span class="hlt">basin</span> are complex, characterized by temporally variable storage volumes with erratic contribution to streamflow. For the continual usage of groundwater resources in the floodplains there is a need to study the form of interaction between the main river and floodplain wetlands. The study, adopted the PM-WIN (MODFLOW) model for simulating the interaction between the wetland and stream. Additionally, the lower boundary discharge output from the HYDRUS-1D model is the estimated recharge. This input quantifies the temporal and spatial variations in sub-surfaces discharges in the floodplain wetland. The simulation of the sub-surface hydraulic head of the wetland indicates a systematic variation relative to the White Volta River response to changes in the rainfall pattern. The interaction conditions vary from season to season with March, April, and May showing the least leakage (estimated values of 0.03mm/day, 0.06mm/day, and 0.15 mm/day, respectively) from the river into the floodplain wetland. Notably, the interaction between the wetland and the river as simulated is bidirectional. With most of the flow coming out from the river into the floodplain wetland, this condition persists in the months of August and September.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.V53D3150H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.V53D3150H"><span>Investigating Controls on Sedimentation Through Interpretation of the Syntectonic Cretaceous-Paleogene <span class="hlt">Sedimentary</span> Record in the San Juan <span class="hlt">Basin</span> (New Mexico, U.S.A.)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hobbs, K.; Weissmann, G. S.; Fawcett, P. J.</p> <p>2015-12-01</p> <p>The Cretaceous/Paleogene boundary in the southwestern San Juan <span class="hlt">Basin</span> is bracketed by the mudstone-dominated Cretaceous Kirtland Formation, the sandstone-dominated Paleocene Ojo Alamo Sandstone, and the mudstone-dominated Paleocene lower Nacimiento Formation. Geochemical trends of fluvial mudstones from these units indicate changing <span class="hlt">sedimentary</span> source areas through time. While the Kirtland and Nacimiento Formations represent periods of high accommodation within the San Juan <span class="hlt">Basin</span>, the Ojo Alamo Sandstone represents a period of low accommodation and general reworking and transport by southeast-flowing paleorivers. The Kirtland and Nacimiento Formations thin and fine away from their interpreted source area whereas the Ojo Alamo Sandstone thickens and fines away from the source area. Here we investigate the enigmatic <span class="hlt">sedimentary</span> architecture of the Ojo Alamo Sandstone, geochemical evidence for a changing source area through this time period, and the complex relationships between sedimentation, source area, accommodation, and <span class="hlt">basin</span> tectonic evolution. Incorporating new measured sections, petrographic analyses, geochemical trends, and stratigraphic relationships, we propose that the Ojo Alamo Sandstone represents an anomalous short period of low accommodation in the San Juan <span class="hlt">Basin</span> during the early Laramide Orogeny and explore possible intra- and extra-<span class="hlt">basinal</span> tectonic, climatic, and sedimentologic explanations as well as implications for understanding the evolution of the <span class="hlt">basin</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6209755','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6209755"><span><span class="hlt">Sedimentary</span> facies, organic facies, and hydrocarbon generation in evaporite sediments of the Mulhouse <span class="hlt">Basin</span>, France</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hofmann, P.M.</p> <p>1992-01-01</p> <p>The sediments of the S unit (lower Oligocene) of the Mulhouse <span class="hlt">Basin</span>, France, display lithofacies characteristic for the deposition in a perennial evaporitic lake that received frequent marine influx. The sediments consist of marls, anhydrites, and halite. The organic content of these sediments stems from algal and most likely bacterial sources. Terrigenous, plant-derived organic matter comprises on average less than 10% of the total organic matter. The mass of the organic matter is concentrated in the marl lithofacies, which display a varve-like lamination. The 2 organic racies correlate with distinct lithofacies. It therefore appears that the deposition of sediments and their organic content was governed by the physical conditions of the lake. The accumulation of organic matter-rich sediments in the S unit of the Mulhouse <span class="hlt">Basin</span> is thought to have been favored by a high paleoproductivity and good to excellent preservation conditions. Low sedimentation rates in conjunction with elevated salinities led to the accumulation of marls rich in organic matter. The kerogens of the S unit can be classified as type II. The organic matter from the sites Amelie II and Berrwiller is immature and corresponds to a maturity level of 0.35 and 0.45% vitrinite reflectance. Petroleum formation resulted in significantly higher amounts of bitumen as expected from shale source rocks of this maturity level. The bitumens are dominated by asphaltenes and NSO-compounds and contain less than 50% hydrocarbons. In the maturity interval from 0.35-0.45% R[sub o], hydrocarbon generation took place in all lithofacies. Hydrocarbons formed via kerogen conversion in the marl-dominated sediments and via asphaltene/NSO-compound conversion in anhydrite-dominated lithofacies. The massive anhydrites of the S unit have already expelled hydrocarbons. The naphthalene patterns of this lithofacies show fractionation effects that resulted from water washing during the phase transition from gypsum to anhydrite.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GCarp..67..525S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GCarp..67..525S"><span>Late Miocene <span class="hlt">sedimentary</span> record of the Danube/Kisalföld <span class="hlt">Basin</span>: interregional correlation of depositional systems, stratigraphy and structural evolution</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sztanó, Orsolya; Kováč, Michal; Magyar, Imre; Šujan, Michal; Fodor, László; Uhrin, András; Rybár, Samuel; Csillag, Gábor; Tőkés, Lilla</p> <p>2016-12-01</p> <p>The Danube / Kisalföld <span class="hlt">Basin</span> is the north-western sub-<span class="hlt">basin</span> of the Pannonian <span class="hlt">Basin</span> System. The lithostratigraphic subdivision of the several-km-thick Upper Miocene to Pliocene <span class="hlt">sedimentary</span> succession related to Lake Pannon has been developed independently in Slovakia and Hungary. A study of the <span class="hlt">sedimentary</span> formations across the entire <span class="hlt">basin</span> led us to claim that these formations are identical or similar between the two <span class="hlt">basin</span> parts to such an extent that their correlation is indeed a matter of nomenclature only. Nemčiňany corresponds to the Kálla Formation, representing locally derived coarse clastics along the <span class="hlt">basin</span> margins (11- 9.5 Ma). The deep lacustrine sediments are collectively designated the Ivanka Formation in Slovakia, while in Hungary they are subdivided into Szák (fine-grained transgressive deposits above basement highs, 10.5 - 8.9 Ma), Endrőd (deep lacustrine marls, 11.6 -10 Ma), Szolnok (turbidites, 10.5 - 9.2 Ma) and Algyő Formations (fine-grained slope deposits, 10 - 9 Ma). The Beladice Formation represents shallow lacustrine deltaic deposits, fully corresponding to Újfalu (10.5 - 8.7 Ma). The overlying fluvial deposits are the Volkovce and Zagyva Formations (10 - 6 Ma). The synoptic description and characterization of these sediments offer a <span class="hlt">basin</span>-wide insight into the development of the <span class="hlt">basin</span> during the Late Miocene. The turbidite systems, the slope, the overlying deltaic and fluvial systems are all genetically related and are coeval at any time slice after the regression of Lake Pannon initiated about 10 Ma ago. All these formations get younger towards the S, SE as the progradation of the shelf-slope went on. The <span class="hlt">basin</span> got filled up to lake level by 8.7 Ma, since then fluvial deposition dominated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoJI.205..744E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoJI.205..744E"><span>Measurement of intrinsic and scattering attenuation of shear waves in two <span class="hlt">sedimentary</span> <span class="hlt">basins</span> and comparison to crystalline sites in Germany</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Eulenfeld, Tom; Wegler, Ulrich</p> <p>2016-05-01</p> <p>We developed an improved method for the separation of intrinsic and scattering attenuation of seismic shear waves by envelope inversion called Qopen. The method optimizes the fit between Green's functions for the acoustic, isotropic radiative transfer theory and observed energy densities of earthquakes. The inversion allows the determination of scattering and intrinsic attenuation, site corrections and spectral source energies for the investigated frequency bands. Source displacement spectrum and the seismic moment of the analysed events can be estimated from the obtained spectral source energies. We report intrinsic and scattering attenuation coefficients of shear waves near three geothermal reservoirs in Germany for frequencies between 1 and 70 Hz. The geothermal reservoirs are located in Insheim, Landau (both Upper Rhine Graben) and Unterhaching (Molasse <span class="hlt">basin</span>). We compare these three <span class="hlt">sedimentary</span> sites to two sites located in crystalline rock with respect to scattering and intrinsic attenuation. The inverse quality factor for intrinsic attenuation is constant in sediments for frequencies smaller than 10 Hz and decreasing for higher frequencies. For crystalline rock, it is on a lower level and strictly monotonic decreasing with frequency. Intrinsic attenuation dominates scattering except for the Upper Rhine Graben, where scattering is dominant for frequencies below 10 Hz. Observed source displacement spectra show a high-frequency fall-off greater than or equal to 3.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008CG.....34..427M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008CG.....34..427M"><span>Two equations of state assembled for basic analysis of multiphase CO 2 flow and in deep <span class="hlt">sedimentary</span> <span class="hlt">basin</span> conditions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McPherson, Brian J. O. L.; Han, Weon Shik; Cole, Barret S.</p> <p>2008-05-01</p> <p>The purpose of the study presented in this manuscript is to describe and make available two equation-of-state (EOS) algorithms assembled for multiphase flow and transport of carbon dioxide (CO2). The algorithms presented here calculate solubility, compressibility factor, density, viscosity, fugacity, and enthalpy of CO2 in gaseous and supercritical phases, and mixtures or solutions of CO2 in water, as functions of pressure and temperature. Several features distinguish the two algorithms, but the primary distinction concerns treatment of supercritical/gas-phase CO2: one EOS we assembled is based on Redlich and Kwong's original algorithm developed in 1949, and the other is based on an algorithm developed by Span and Wagner in 1996. Both were modified for application to <span class="hlt">sedimentary</span> <span class="hlt">basin</span> studies of multiphase CO2 flow processes, including carbon sequestration applications. We present a brief comparison of these two EOS algorithms. Source codes for both algorithms are provided, including "stand-alone" Matlab © scripts for the interactive calculation of fluid properties at specified P-T conditions and FORTRAN subroutines for inclusion in existing FORTRAN multiphase fluid simulation packages. These routines are intended for fundamental analyses of CO2 sequestration and the like; more advanced studies, such as brine processes and reactive transport, require more advanced EOS algorithms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70015679','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70015679"><span>Geochemistry and diagenesis of Miocene lacustrine siliceous <span class="hlt">sedimentary</span> and pyroclastic rocks, Mytilinii <span class="hlt">basin</span>, Samos Island, Greece</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Stamatakis, M.G.; Hein, J.R.; Magganas, A.C.</p> <p>1989-01-01</p> <p>A Late Miocene non-marine stratigraphic sequence composed of limestone, opal-CT-bearing limestone, porcelanite, marlstone, diatomaceous marlstone, dolomite, and tuffite crops out on eastern Samos Island. This lacustrine sequence is subdivided into the Hora Beds and the underlying Pythagorion Formation. The Hora Beds is overlain by the clastic Mytilinii series which contains Turolian (Late Miocene) mammalian fossils. The lacustrine sequence contains volcanic glass and the silica polymorphs opal-A, opal-CT, and quartz. Volcanic glass predominantly occurs in tuffaceous rocks from the lower and upper parts of the lacustrine sequence. Opal-A (diatom frustules) is confined to layers in the upper part of the Hora Beds. Beds rich in opal-CT underlie those containing opal-A. The occurrence of opal-CT is extensive, encompassing the lower Hora Beds and the <span class="hlt">sedimentary</span> rocks and tuffs of the Pythagorion Formation. A transition zone between the opal-A and opal-CT zones is identified by X-ray diffraction patterns that are intermediate between those of opal-CT and opal-A, perhaps due to a mixture of the two polymorphs. Diagenesis was not advanced enough for opal-CT to transform to quartz or for volcanic glass to transform to opal-C. Based on geochemical and mineralogical data, we suggest that the rate of diagenetic transformation of opal-A to opal-CT was mainly controlled by the chemistry of pore fluids. Pore fluids were characterized by high salinity, moderately high alkalinity, and high magnesium ion activity. These pore fluid characteristics are indicated by the presence of evaporitic salts (halite, sylvite, niter), high boron content in biogenic silica, and by dolomite in both the opal-A and opal-CT-bearing beds. The absence of authigenic K-feldspar, borosilicates, and zeolites also support these pore fluid characteristics. Additional factors that influenced the rate of silica diagenesis were host rock lithology and the relatively high heat flow in the Aegean region from</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AGUFM.U62A..08C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AGUFM.U62A..08C"><span>Flow-Through, Low Retention Hydrocarbon Generation in Active <span class="hlt">Sedimentary</span> <span class="hlt">Basins</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cathles, L. M.</p> <p>2002-12-01</p> <p>Hydrocarbons are typically generated when thin (<100 m), organic-rich strata are buried. Oil is generated first, then gas. Detailed investigation of the chemistry of hydrocarbons in a 100 (E-W) x 200 (N-S) km study area in the offshore Louisiana Gulf of Mexico <span class="hlt">Basin</span> shows that the early-generated oils there have been extensively altered by interaction with late-generated gas, producing a remarkably regular pattern in which over 90 wt% of the n-alkanes have been removed by gas washing in the north while none have been so removed in the south. Straight-forward (Turcottian) physical-chemical modeling suggests this pattern can be produced only if the retention of hydrocarbons between source and seafloor is very low (0.1% of the pore space). This low retention means that about 80% or 120 billion tones (Bt) of the ~149 Bt of hydrocarbons that have been generated and expelled from the source strata in the study area have been vented into the ocean. This mass of vented hydrocarbons is 100 times the mass of hydrocarbon in known reservoirs in the area (1.4 Bt or 11 billon barrels of oil and gas equivalent). The reservoired hydrocarbons are about 5% of the hydrocarbons retained in the models between the source and seafloor. To be properly washed, the reservoired hydrocarbons must also have been very recently introduced. The hydrocarbon system in the study area is thus one of massive venting with minor, constantly replenished (flow through) retention. The predicted current rates of venting are confirmed by independent estimates of the rate of hydrate accumulation in the southern part of the study area. The massive venting of over 900 billion barrels (equivalent) of hydrocarbons, an amount about equal to the total world consumption of oil to date, from a 100 x 200 km portion of one <span class="hlt">basin</span> in a relatively short timespan (about 20 Ma) provides an interesting geologic context for human production and consumption. The rapid venting also has potentially important implications for the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6130082','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6130082"><span>Cementation and compaction history of synorogenic foreland <span class="hlt">basin</span> <span class="hlt">sedimentary</span> rocks from Huaco, Argentina</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Damanti, J.F.; Jordan, T.E.</p> <p>1989-07-01</p> <p>The Sierra de Huaco exposes the western flank of the Bermejo foreland <span class="hlt">basin</span> of central western Argentina. The exposed 5400-m section is well dated (14-2.3 Ma) and consists of synorogenic continental strata. Petrographic data combined with decompaction techniques provide first-order estimates of the absolute age of cementation of the sandstones. This information can be used to interpret petroleum migration paths and reservoir potential. Three diagenetic zones have been recognized, each characterized by a dominant cementing material within a distinct framework texture. These textures reflect varying degrees of compaction and framework-grain replacement prior to cementation. The diagenetic histories of the three zones were genetically linked to thrusting in the adjacent Precordillera, changes in depositional environment, and subsurface fluid flow. The depth at which cementation occurred in each zone is constrained by comparison of observed intergrain volume to predicted volumes (for uncemented sands) at any given burial depth. First-order estimates of the absolute age of cementation in each zone were made possible by comparing these relationships with a curve of accumulation history of the decompacted strata. The lowest zone compacted with little interstitial cement for as long as 11 m.y. after deposition. The middle zone was cemented within 3 m.y. after deposition. The upper zone experienced framework-grain replacement by calcite at very shallow depths within 2 m.y. and experienced little compaction. 14 figures, 1 table.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..1111859B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..1111859B"><span>Ejected <span class="hlt">Sedimentary</span> Rocks of Mud Volcanoes as Indicators of Depositional Environments and of Hydrocarbon Generation within the South Caspian <span class="hlt">Basin</span>, Azerbaijan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Berner, U.; Scheeder, G.; Kus, J.; Köthe, A.; Movsumova, U.</p> <p>2009-04-01</p> <p>Mud volcanoes are prominent geological features of the South Caspian <span class="hlt">Basin</span> of Azerbaijan, one of the oldest oil producing regions worldwide. The <span class="hlt">basin</span> is characterized by extreme sedimentation rates, which lead to the accumulation of <span class="hlt">large</span> volumes of Mesozoic and Cenozoic sediments. These mostly unconsolidated strata reach thicknesses of up to 20 km and overlay a continental basement in the onshore part. Tectonic forces control the occurrences of mud volcanoes in regions with over-pressured subsurface sediments as mud volcanoes are closely linked to fault systems. The mud volcanoes of Azerbaijan are a surface expression of vertical hydrocarbon migration and offer the chance to investigate the subsurface by means of ejected rocks transported to the surface. These rocks of Mesozoic and Cenozoic <span class="hlt">sedimentary</span> sequences are potential indicators of the regional hydrocarbon generation. The mud of nineteen volcano cones contained numerous ejected rock fragments, which we use to identify environmental and depositional parameters of the sediments of the Caspian <span class="hlt">Basin</span>. We also intended to estimate the depth range from which the mud was transported to the surface using organic geochemical parameters. Mircopalaeontological investigations (calcareous nannoplankton) have been performed on selected samples. These analyses suggest that the investigated sediments are of Late Cretaceous to Palaeogene ages and relate to the stratigraphic interval during which the main hydrocarbon source rocks of Azerbaijan have been deposited. Organic geochemical, organic petrographical and mircopalaeontological investigations have been performed on selected samples of nineteen mud volcanoes. Analyses total organic carbon and total sulphur were performed on an elemental analyzer. These analyses suggest that the sediments can be classified as anoxic marine deposits whereas only few are sediments of a lacustrine environment. Bulk source rock information were obtained from RockEval pyrolysis. Resulting</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007EM%26P..101..153B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007EM%26P..101..153B"><span>A <span class="hlt">Large</span> <span class="hlt">Basin</span> on the Near Side of the Moon</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Byrne, Charles Joseph</p> <p>2007-12-01</p> <p>The differences between the surface structure of the near side and the far side of the Moon have been topics of interest ever since photographs of the far side have been available. One recurrent hypothesis is that a <span class="hlt">large</span> impact on the near side has deposited ejecta on the far side, resulting in thicker crust there. Specific proposals were made by P.H. Cadogan for the Gargantuan <span class="hlt">Basin</span> and by E.A. Whitaker for the Procellarum <span class="hlt">Basin</span>. Despite considerable effort, no consensus has been reached on the existence of these <span class="hlt">basins</span>. The problem of searching for such a <span class="hlt">basin</span> is one of finding its signature in a somewhat chaotic field of <span class="hlt">basin</span> and crater impacts. The search requires a model of the topographic shape of an impact <span class="hlt">basin</span> and its ejecta field. Such a model is described, based on elevation data of lunar <span class="hlt">basins</span> collected by the Lidar instrument of the Clementine mission and crustal thickness data derived from tracking Clementine and other spacecraft. The parameters of the model are scaled according to the principles of dimensional analysis and isostatic compensation in the early Moon. The orbital dynamics of the ejecta and the curvature of the Moon are also taken into account. Using such a scaled model, a search for the best fit for a <span class="hlt">large</span> <span class="hlt">basin</span> led to identification of a <span class="hlt">basin</span> whose cavity covers more than half the Moon, including the area of all of the impact <span class="hlt">basins</span> visible on the near side. The center of this <span class="hlt">basin</span> is at 22 degrees east longitude and 8.5 degrees north latitude and its average radius is approximately 3,160 km. It is a megabasin, a <span class="hlt">basin</span> that contains other <span class="hlt">basins</span> (the far side South Pole-Aitken <span class="hlt">Basin</span> also qualifies for that designation). It has been called the Near Side Megabasin. Much of the material ejected from the <span class="hlt">basin</span> escaped the Moon, but the remainder formed an ejecta blanket that covered all of the far side beyond the <span class="hlt">basin</span> rim to a depth of from 6 to 30 km. Isostatic compensation reduced the depth relative to the mean surface to a range</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeCoA.192...49S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeCoA.192...49S"><span>Impact of cable bacteria on <span class="hlt">sedimentary</span> iron and manganese dynamics in a seasonally-hypoxic marine <span class="hlt">basin</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sulu-Gambari, Fatimah; Seitaj, Dorina; Behrends, Thilo; Banerjee, Dipanjan; Meysman, Filip J. R.; Slomp, Caroline P.</p> <p>2016-11-01</p> <p>Cable bacteria have recently been identified in various <span class="hlt">sedimentary</span> marine settings worldwide. These filamentous microbes mediate electrogenic sulphur oxidation (e-SOx) over centimetre-scale distances, leading to a distinct separation of oxygen- and sulphide-bearing sediment zones. Here we present results of a year-long monthly assessment of the impact of cable bacteria on <span class="hlt">sedimentary</span> Fe and Mn dynamics at three sites located along a water depth gradient in a seasonally-hypoxic coastal marine lake (Grevelingen, The Netherlands). Fluorescence In Situ Hybridisation (FISH) shows the presence of cable bacteria at two sites in spring. Micro-sensor profiling (O2, pH, H2S) and pore water profiles of dissolved Mn, Fe2+, Ca2+ and SO42- reveal the geochemical signature of e-SOx at these sites, i.e. the development of a broad suboxic zone, characterised by a low pH and acidic dissolution of Ca/Mn carbonates and Fe sulphides. Cable bacteria activity, as reflected by dissolution of FeS in spring, was highest at the deepest and most hypoxic site. In spring, dissolved Mn and Fe2+ released at depth due to e-SOx diffused upwards and was sequestered as Mn- and Fe-(oxyhydr)oxides near the sediment surface, with Mn oxides acting as an oxidant for part of the upward diffusing Fe2+. Strikingly, the thickness of the Fe-(oxyhydr)oxide-bearing surface layer of the sediment was greatest at the most hypoxic site, emphasising the key role of cable bacteria in creating oxidised surface sediments. X-ray absorption fine structure analyses confirm the seasonality in Fe-(oxyhydr)oxide formation and reveal that the sediment Mn oxides were of biogenic (birnessite) and abiotic (hausmannite) origin. Upon the onset of hypoxia in early summer, the sediment Fe-(oxyhydr)oxides were mostly converted to Fe-sulphides but the Mn oxides dissolved and the Mn was lost to the overlying water. After summer hypoxia, Beggiatoaceae mats colonised the sediment with little further change in sediment geochemistry. Our</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.H11J..06T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.H11J..06T"><span>A Hydraulic Tomography Experiment in Fractured <span class="hlt">Sedimentary</span> Rocks, Newark <span class="hlt">Basin</span>, New Jersey, USA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tiedeman, C. R.; Barrash, W.; Thrash, C. J.; Johnson, C. D.</p> <p>2015-12-01</p> <p>Hydraulic tomography was performed in July 2015 in contaminated fractured mudstone beds at the former Naval Air Warfare Center (NAWC) in the Newark <span class="hlt">Basin</span> near Trenton, NJ using seven existing wells. The spatial arrangement of wells (in a circle of 9 m radius with one central well), the use of packers to divide the wells into multiple monitoring intervals, and the deployment of fiber optic pressure transducers enabled collection of a hydraulic tomography dataset comprising high-resolution drawdown observations at an unprecedented level of spatial detail for fractured rocks. The experiment involved 45-minute cross-hole aquifer tests, conducted by pumping from a given packer-isolated well interval and continuously monitoring drawdowns in all other well intervals. The collective set of drawdown data from all tests and intervals displays a wide range of behavior suggestive of highly heterogeneous hydraulic conductivity (K) within the tested volume, such as: drawdown curves for different well intervals crossing one another on drawdown-time plots; variable drawdown curve shapes, including linear segments on log-log plots; variable order and magnitude of time-lag and/or drawdown for intervals of a given well in response to pumping from similar fractures or stratigraphic units in different wells; and variable groupings of wells and intervals showing similar responses for different pumping tests. The observed behavior is consistent with previous testing at the NAWC indicating that K within and across individual mudstone beds can vary by orders of magnitude over scales of meters. Preliminary assessment of the drawdown data together with a rich set of geophysical logs suggests an initial conceptual model that includes densely distributed fractures of moderate K at the shallowest depths of the tested volume, connected high-K bedding-plane-parting fractures at intermediate depths, and sparse low-K fractures in the deeper rocks. Future work will involve tomographic inversion of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/543079','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/543079"><span><span class="hlt">Sedimentary</span> record and climatic implications of recurrent deformation in the Tian Shan: Evidence from Mesozoic strata of the north Tarim, south Junggar, and Turpan <span class="hlt">basins</span>, northwest China</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hendrix, M.S.; Graham, S.A.; Sobel, E.R.</p> <p>1992-01-01</p> <p>Detailed stratigraphic, sedimentologic, paleocurrent, and subsidence analyses were conducted on Mesozoic nonmarine <span class="hlt">sedimentary</span> sections of the south Junggar, north Tarim, and Turpan <span class="hlt">basins</span>, Xinjang Uygur Autonomous Region, northwest China. These three <span class="hlt">basins</span> have been foreland <span class="hlt">basins</span> throughout the Mesozoic and Cenozoic eras, as demonstrated by asymmetrically distributed basinwide sediment accumulations, foreland-style subsidence profiles, and a variety of outcrop and subsurface facies data. Mesozoic paleocurrent indicators measured in the south Junggar and north Tarim <span class="hlt">basins</span>, as well as Mesozoic sandstone compositions from both <span class="hlt">basins</span>, indicate that the intervening Tian Shan has existed as a positive physiographic feature partitioning the two <span class="hlt">basins</span> throughout Mesozoic and Cenozoic time. Paleocurrent, facies, and subsurface isopach data suggest that the Turpan <span class="hlt">basin</span> was established as a discrete feature by the Early Jurassic period. The timing and style of depositional systems within the north Tarim Mesozoic depocenter, the south Junggar Mesozoic depocenter, and the central Turpan <span class="hlt">basin</span> are remarkably similar. Upper Triassic strata of each <span class="hlt">basin</span> consist of alluvial conglomerate and associated braided-fluvial sandstone and siltstone which fine upward into lower through Middle Jurassic, locally organic-rich, meandering-fluvial, and lacustrine strata. Upper Jurassic braided-fluvial red beds in each <span class="hlt">basin</span> are overlain by a distinct pulse of uppermost Jurassic alluvial conglomerate. Lower Cretaceous exposures consist of fine-grained red beds in north Tarim and Turpan and interbedded red and gray shale with local silty carbonates in south Junggar. Upper Cretaceous strata of the north Tarim and south Junggar <span class="hlt">basins</span> are composed of alluvial conglomerate with associated braided-fluvial sandstone and siltstone. 94 refs., 17 figs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.H23D1221M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.H23D1221M"><span><span class="hlt">Large</span> <span class="hlt">sedimentary</span> aquifer system and sustainable management: investigations of hydrogeological and geochemical variations in Eocene sand aquifer, south western France</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Malcuit, E.; Negrel, P. J.; Petelet-Giraud, E.; Durst, P.</p> <p>2010-12-01</p> <p>In the <span class="hlt">sedimentary</span> Aquitaine <span class="hlt">Basin</span>, the Eocene Sand Aquifer system, mostly confined, represents strategic resources for drinking water, irrigation, gas storage and geothermal resources. Therefore, its quantity and quality issues are essential for the sustainable management in this <span class="hlt">large</span> region that extends over 116,000 km2 (i.e. one-fifth of the French territory). The Eocene Sand Aquifer system comprises at least five aquifers: Paleocene, Eocene infra-molassic sands, early Eocene, middle Eocene, and late Eocene. The extension and thickness of Eocene aquifer layers and negative confined layers vary throughout the <span class="hlt">basin</span>, from several tens of metres to a hundred metres. The deposit sequences characterizing the Eocene Aquifer System are progradational westward from detrital deposits to carbonates. Eocene sands and Eocene limestones are hydraulically connected and covered by an aquiclude of up to several hundred metres thick of molassic sediments. The groundwater recharge is assumed to occur through the Eocene outcrops located in the north and north-east, and in the south east in contact with the Montagne Noire as well as by vertical leakage from the upper and lower aquifers. Another recharge is suspected in the south near the Petites Pyrenees. According to isotopic data, both present-day recharge and old recharge (16-35 ky) can be evidenced. The north and south evolutions of the piezometric surface are different. In the north, because of years of pumping, a trough in the potentiometric surface has been formed. The piezometric decline is roughly one meter per year in the depression centre. In the south, the decline of the water table is roughly half a meter per year. Furthermore, in the south part, around two sites of gas storage, significant fluctuations of the potentiometric surface are superimposed to the variations resulting from water abstraction, due to the injection and abstraction of gas. However, a major difficulty for the sustainable management is the lack of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.T31C1826B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.T31C1826B"><span>Structural Evolution of a <span class="hlt">Large</span> Extensional <span class="hlt">Basin</span> Near Charleston, SC, Illuminated By Seismic-Reflection Profiling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Beale, J. N.; Chapman, M. C.</p> <p>2009-12-01</p> <p>A comprehensive re-examination and reprocessing of 1980s-vintage seismic-reflection data collected near Charleston, South Carolina, which lies within the South Georgia Rift, has revealed evidence of significant crustal extension and coeval magmatic activity, as well as apparent <span class="hlt">basin</span> inversion and a late-stage episode of mafic volcanism. The South Georgia Rift is comprised of several <span class="hlt">large</span> extensional <span class="hlt">basins</span> separated by intervening structural highs, and is a failed Triassic-Jurassic rift separating the Appalachian Piedmont terrane to the north from the Suwannee terrane to the south. Gravity and magnetic modeling indicate that a significant amount of mafic rock lies within the upper crust near Charleston. Seismic profiles show bright reflections within the early-Mesozoic basement rock beneath the Atlantic Coastal Plain sediments that probably represent the interface between clastic sediments and basalt layers. These basalt layers have been sparsely sampled by deep drilling within the South Georgia Rift. The seismic data from Charleston, together with crustal scale, seismic-reflection data from Georgia, show the evolution of the rifting process from the extensional phase which produced the <span class="hlt">large</span> <span class="hlt">basins</span> and high rates of sedimentation, through the compressional phase which produced uplift and erosion leading to an inverted <span class="hlt">basin</span> geometry. Additionally, in the Charleston area, the seismic data show a basalt layer that forms the post-rift unconformity over most of the area. This basalt layer is not present on most of the profiles in Georgia, where the base of the coastal plain sediments is rift-related <span class="hlt">sedimentary</span> rock. Significantly, near Charleston this basalt layer lacks the <span class="hlt">large</span> amount of deformation that is characteristic of all of the imaged basalt layers beneath it. This suggests that there is a significant separation in time between the syn-rift basalt layers and the apparently post-rift basalt layer at the top of the rift sequence.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007SedG..197..127Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007SedG..197..127Y"><span>Geochemistry of the <span class="hlt">sedimentary</span> rocks from the Nanxiong <span class="hlt">Basin</span>, South China and implications for provenance, paleoenvironment and paleoclimate at the K/T boundary</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yan, Yi; Xia, Bin; Lin, Ge; Cui, Xuejun; Hu, Xiaoqiong; Yan, Pin; Zhang, Faqiang</p> <p>2007-04-01</p> <p>Cretaceous and Tertiary clastic <span class="hlt">sedimentary</span> rocks from the Nanxiong <span class="hlt">Basin</span>, South China have been analyzed to constrain their provenance, depositional climate and environment. Evidence from discrimination diagrams for <span class="hlt">sedimentary</span> provenance and tectonic setting show that the Nanxiong <span class="hlt">Basin</span> sediments were derived from typical continental sources. Geochemical signatures (e.g. Eu/Eu *, Th/Ti, La/Ti, Ta/Ti, Yb/Ti and Y/Ti ratios of the claystone) are nearly constant, suggesting the provenance of the Nanxiong <span class="hlt">Basin</span> remained similar throughout the Late Cretaceous to Early Paleocene (83-56 Ma). In contrast Rb/Ti, Cs/Ti ratios and TOC and CaCO 3 concentrations require an obvious change in climate across the Late Cretaceous and Early Paleocene boundary. Singularly higher CaCO 3 contents and lower TOC values and Rb/Ti, Cs/Ti ratios in the Late Cretaceous indicate that a long period extreme dry climate occurred at that time in South China. Rb/Ti, Cs/Ti ratios and TOC values escalated and CaCO 3 contents decreased in the Early Paleocene suggesting that the climate became relatively wet, which resulted in greater vegetation cover. The lasting extreme dry climate in the Late Cretaceous may provide a clue to the extinction of the dinosaurs in the Nanxiong <span class="hlt">Basin</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1993JAfES..16..143S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1993JAfES..16..143S"><span>A review of the stratigraphy and <span class="hlt">sedimentary</span> environments of the Karoo-aged <span class="hlt">basins</span> of Southern Africa</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Smith, R. M. H.; Eriksson, P. G.; Botha, W. J.</p> <p>1993-02-01</p> <p>The Karoo <span class="hlt">Basin</span> of South Africa was one of several contemporaneous intracratonic <span class="hlt">basins</span> in southwestern Gondwana that became active in the Permo-Carboniferous (280 Ma) and continued to accumulate sediments until the earliest Jurassic, 100 million years later. At their maximum areal extent, during the early Permian, these <span class="hlt">basins</span> covered some 4.5 million km 2. The present outcrop area of Karoo rocks in southern Africa is about 300 000 km 2 with a maximum thickness of some 8000 m. The economic importance of these sediments lies in the vast reserves of coal within the Ecca Group rocks of northern and eastern Transvaal and Natal, South Africa. <span class="hlt">Large</span> reserves of sandstone-hosted uranium and molybdenum have been proven within the Beaufort Group rocks of the southern Karoo trough, although they are not mineable in the present market conditions. Palaeoenvironmental analysis of the major stratigraphic units of the Karoo succession in South Africa demonstrates the changes in depositional style caused by regional and localized tectonism within the <span class="hlt">basin</span>. These depocentres were influenced by a progressive aridification of climate which was primarily caused by the northward drift of southwestern Gondwana out of a polar climate and accentuated by the meteoric drying effect of the surrounding land masses. Changing palaeoenvironments clearly influenced the rate and direction of vertebrate evolution in southern Gondwana as evidenced by the numerous reptile fossils, including dinosaurs, which are found in the Karoo strata of South Africa, Lesotho, Namibia and Zimbabwe. During the Late Carboniferous the southern part of Gondwana migrated over the South Pole resulting in a major ice sheet over the early Karoo <span class="hlt">basin</span> and surrounding highlands. Glacial sedimentation in upland valleys and on the lowland shelf resulted in the Dwyka Formation at the base of the Karoo Sequence. After glaciation, an extensive shallow sea covered the gently subsiding shelf, fed by <span class="hlt">large</span> volumes of meltwater</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008PEPI..169..131L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008PEPI..169..131L"><span>Morphology of the Iceland <span class="hlt">Basin</span> Excursion from a spherical harmonics analysis and an iterative Bayesian inversion procedure of <span class="hlt">sedimentary</span> records</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lanci, Luca; Kissel, Catherine; Leonhardt, Roman; Laj, Carlo</p> <p>2008-08-01</p> <p>Based on 5 published marine high-resolution <span class="hlt">sedimentary</span> records of the Iceland <span class="hlt">Basin</span> Excursion [IBE; Channell, J.E.T., Hodell, D.A., Lehman, B., 1997. Relative geomagnetic paleointensity and ∂ 18O at ODP Site 983/Gardar Drift, North Atlantic since 350 ka. Earth Planet. Sci. Lett. 153, 103-118; Laj, C., Kissel, C., Roberts, A., 2006. Geomagnetic field behavior during the Iceland <span class="hlt">Basin</span> and Laschamp geomagnetic excursions: a simple transitional field geometry? Geochem. Geophys. Geosystems. 7, Q03004, doi:10.1029/2005GC001122] dated around 186-190 kyr, we present models of the excursional geomagnetic field at the Earth's surface using two different approaches. First a spherical harmonics analysis is performed after synchronization of the records using their paleointensity profiles. Second, we have used an iterative Bayesian inversion procedure, calibrated using the single volcanic data available so far. Both modeling approaches suffer from imperfections of the paleomagnetic signals and mostly from the still poor geographical distribution of detailed records, presently available only from the North Atlantic and the West Pacific. For these reasons, our modeling results should only be regarded as preliminary models of the geomagnetic field during the IBE, susceptible to improvements when including results from future paleomagnetic studies. Nevertheless, both approaches show distinct similarities and are stable against moderate variations of modeling parameters. The general picture is that of a dipole field undergoing a strong reduction, but remaining higher than the non-dipole field all through the excursional process, except for a very short interval of time corresponding to the dipole minimum at the center of the excursion. On the other hand, some differences exist between the results of the two models with each other and with the real data when the virtual geomagnetic pole (VGP) paths are considered. The non-dipole field does not appear to undergo very significant</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009JSAES..28..180B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009JSAES..28..180B"><span>Paleoenvironments and origin of the <span class="hlt">sedimentary</span> phosphorites of the Napo Formation (Late Cretaceous, Oriente <span class="hlt">Basin</span>, Ecuador)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brookfield, M. E.; Hemmings, D. P.; Van Straaten, P.</p> <p>2009-08-01</p> <p>The Napo phosphorites were deposited at the edge of a stable marine shelf during the Upper Cretaceous (Coniacian) oceanic anoxic event (OAE 3) at the transition from bioclastic limestone to organic-rich shale facies. Phosphogenesis was triggered in the shelf margin environment by a number of factors including strong upwelling currents, high biological activity, plankton blooms, and <span class="hlt">large</span> amounts of organic matter production and subsequent accumulation. Dissolved phosphate levels increased in the sediment from a combination of anoxic conditions and microbial activity. Once dissolved phosphate concentrations were high enough, apatite began to form around nucleic sites including mineral grains, shells, wood fragments, and foraminifera tests forming peloidal fluorine rich carbonate fluoroapatite (francolite). As the peloids formed, sedimentation continued and dissolved phosphate concentrations diminished. A period of minor winnowing ensued, and as dissolved phosphate concentrations remained low, shale layers were deposited separating the various phosphate layers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997Tectp.271..191E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1997Tectp.271..191E"><span>Structure and tectonic evolution of the Tornquist Zone and adjacent <span class="hlt">sedimentary</span> <span class="hlt">basins</span> in Scania and the southern Baltic Sea area</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Erlström, M.; Thomas, S. A.; Deeks, N.; Sivhed, U.</p> <p>1997-04-01</p> <p>Southernmost Sweden, Bornholm and the surrounding Baltic Sea region are located on a <span class="hlt">large</span>-scale releasing bend in the dextral strike-slip system of the Tornquist Zone, with its resulting pull-apart <span class="hlt">basins</span>. The well constrained geology of Scania and Bornholm has been combined with detailed on- and offshore borehole data and three proprietary marine seismic surveys. This in conjunction with supplementary BABEL deep seismic reflection findings allows a combined 3D interpretation of sediment/structure interactions. As a result, a regional interpretation has emerged which gives a new understanding of the interplay between structural movement on a complex strike-slip fault system (Tornquist Zone) and its intrazonal depressions (Vomb Trough and Colonus Shale Trough) as well as the sedimentation history of associated areas of sediment accumulation (Rønne and Arnager Grabens, Höllviken Halfgraben, Hanö Bay <span class="hlt">Basin</span> and Skurup Platform). Detailed sequential litho- and seismo-stratigraphic descriptions have been possible by combination of the various data sets. This resulted in the clarification or recognition of previously unknown structural limits to sub-<span class="hlt">basins</span> and highs in the study area. A 3D chronological (4D) model for the development of the region is proposed. This model takes into account the long-lived structural history combining elements of strike-slip, extension and inversion tectonics. The deep-seated faulting controlling these structures is integrated with the deep structure as revealed by the BABEL line in this area.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011SedG..241...22S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011SedG..241...22S"><span>Chronology and tectono-<span class="hlt">sedimentary</span> evolution of the Upper Pliocene to Quaternary deposits of the lower Guadalquivir foreland <span class="hlt">basin</span>, SW Spain</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Salvany, Josep Maria; Larrasoaña, Juan Cruz; Mediavilla, Carlos; Rebollo, Ana</p> <p>2011-11-01</p> <p>This paper presents new litho, chrono and magnetostratigraphic data from cores of 23 exploratory boreholes drilled in the Abalario and marshlands areas of the lower Guadalquivir <span class="hlt">basin</span> (the western sector of the Guadalquivir foreland <span class="hlt">basin</span>, SW of Spain). The lithologic logs of these boreholes identify four main <span class="hlt">sedimentary</span> formations, namely: Almonte Sand and Gravel, Lebrija Clay and Gravel, Marismas Clay and Abalario Sand, respectively interpreted as proximal-alluvial, distal-alluvial, alluvial-estuarine and aeolian. From radiocarbon and magnetostratigraphic data, these formations were dated as Upper Pliocene to Holocene. In the marshlands area, three main <span class="hlt">sedimentary</span> sequences are present: an Upper Pliocene to Lower Pleistocene sequence of the Almonte and Lebrija (lower unit) formations, a Pleistocene sequence of the Lebrija (upper unit) and the lower Marismas formations, and a latest Pleistocene to present-day sequence of the upper Marismas Formation. The three sequences began as a rapid alluvial progradation on a previously eroded surface, and a subsequent alluvial retrogradation. In the third sequence, estuarine and marsh sediments accumulated on top of the alluvial sediments. The aeolian sands of the Abalario topographic high developed coeval to alluvial and estuarine sedimentation after the first alluvial progradation, and continuously until the present. Correlation with the surrounding areas show that the sequences are the result of the forebulge uplift of the northern margin of the <span class="hlt">basin</span> (Sierra Morena) and the adjacent Neogene oldest sediments of their northern fringe, both form the main source area of the study formations. This uplift occurred simultaneous to the flexural subsidence (SSE tilting) of the southern part of the <span class="hlt">basin</span>, where <span class="hlt">sedimentary</span> aggradation dominated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.9949T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.9949T"><span>Integrated stratigraphy of the Smirra Coring: a new reference <span class="hlt">sedimentary</span> record for the early Paleogene from the Umbria-Marche <span class="hlt">Basin</span> (Northern Apennines, Italy)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Turtù, Antonio; Lauretano, Vittoria; Catanzariti, Rita; Galeotti, Simone; Lanci, Luca; Moretti, Matteo; Lourens, Lucas J.</p> <p>2016-04-01</p> <p>The early Paleogene represents a critical time interval in Earth's history characterized by prolonged greenhouse conditions, culminating in a series of extreme global warming events (i.e. hyperthermals), as well as <span class="hlt">large</span> uncertainties in the Geological Time Scale. Therefore new, high-resolution, geological records are crucial in providing novel constraints on these topics. The Paleogene Umbria-Marche sections of the Northern Apennines (Italy) have shown to be suitable for integrated stratigraphy allowing regional-to-global correlations and environmental reconstructions across this time interval. Among several well-known sections, a new <span class="hlt">sedimentary</span> record is provided by the Smirra Coring, which recovered an undisturbed sequence of rocks (~120 m from 4 overlapping holes) spanning the upper Scaglia Fms. (early Paleocene - middle Eocene) of the Umbria-Marche pelagic succession. Here we present a new, high-resolution, integrated stratigraphic framework (magnetostratigraphy, calcareous nannofossil biostratigraphy, physical properties, calibrated XRF core scanning and cyclostratigraphy) of the ~93 m composite section drilled in Smirra Holes 1 and 2. The succession extends almost continuously, with modest tectonic disturbance affecting its lowermost part with minor faulting. The resulting magnetic stratigraphy defines a succession of normal and reversed polarity magnetozones. The correlation of the paleomagnetic polarity sequence with the latest Geomagnetic Polarity Timescales (GPTSs; e.g. CK95, GTS 2004 and 2012), also constrained through nannofossil biostratigraphy, shows that the section spans the late Paleocene - middle Eocene from chrons C21n (~46 Ma) to C26r (~60 Ma). The overall sedimentation rates computed at Smirra are fully comparable with those from coeval sections from the Umbria-Marche <span class="hlt">Basin</span>, ranging from ~10 m/Ma, between chrons C21n and C22n, to ~6 m/Ma, between chrons C22r and the base of the section. However, the sedimentation rates vary considerably</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.H23D1219P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.H23D1219P"><span><span class="hlt">Large</span> <span class="hlt">sedimentary</span> aquifer systems functioning. Constraints by classical isotopic and chemical tools, and REE in the Eocene sand aquifer, SW France</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Petelet-Giraud, E.; Negrel, P. J.; Millot, R.; Guerrot, C.; Brenot, A.; Malcuit, E.</p> <p>2010-12-01</p> <p><span class="hlt">Large</span> <span class="hlt">sedimentary</span> aquifer systems often constitute strategic water resources for drinking water supply, agriculture irrigation and industry, but can also represent an energetic resource for geothermal power. <span class="hlt">Large</span> water abstractions can induce complete modification of the natural functioning of such aquifer systems, e.g. with seepage between aquifer layers that can lead to water quality degradation. These <span class="hlt">large</span> aquifer systems thus require rational water management at the <span class="hlt">sedimentary</span> <span class="hlt">basin</span> scale in order to preserve both water quantity and quality. In addition to hydrogeological modelling mainly dealing with water quantity, chemical and isotopic methods were applied to evidence the spatial variability of water characteristics and to turn this into better understanding of hydrosystems functioning. The <span class="hlt">large</span> Eocene Sand aquifer system of the Adour-Garonne <span class="hlt">sedimentary</span> <span class="hlt">basin</span> was studied through various hydrological, chemical and isotopic tools. This system extends over 116,000 km2 (one-fifth of the French territory, located in the South west part). The aquifer being artesian in the west of the district and confined with piezometric levels around 250-m depth in the east. The ‘Eocene Sands’, composed of sandy Tertiary sediments alternating with carbonate deposits, is a multi-layer system with high permeability and a thickness of several tens of metres to a hundred metres..The Eocene Sand aquifer system comprises at least five aquifers: Paleocene, Eocene infra-molassic sands (IMS), early Eocene, middle Eocene, and late Eocene. According to δ18O and δ2H values and estimated 14C ages, both present-day recharge (mainly located in the north of the area) and old recharge (16-35 ky) can be evidenced. High spatial variability was evidenced within a same aquifer layer, with temporal variability over one hydrological cycle limited to a few points located in the recharge areas. These results and especially the very old waters recharged under colder climate combined with the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ECSS..183..392L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ECSS..183..392L"><span><span class="hlt">Sedimentary</span> BSi and TOC quantifies the degradation of the Changjiang Estuary, China, from river <span class="hlt">basin</span> alteration and warming SST</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Maotian; Wang, Hong; Li, Yimiao; Ai, Wei; Hou, Lijun; Chen, Zhongyuan</p> <p>2016-12-01</p> <p>Environmental degradation in the Changjiang Estuary has recently become a global topic, given its proximity to Shanghai with a population >23 million. Intensification of human activities affecting the river <span class="hlt">basin</span> is responsible for this degradation. Dam construction has cut off ca. 2/3 of the sediment flux to the sea, ca. 60% of the dissolved silicate load (DSi) has been retained in the reservoirs, while total phosphorous (TP) and total nitrogen (TN) transport to the sea are many times more than they were a few decades ago. Under such circumstances, details of the estuarine degradation remain poorly understood. This study uses <span class="hlt">sedimentary</span> biological silicate (BSi) and total organic carbon (TOC) as environmental proxies to reveal the process-response of such degradation since the 1950s. Our results demonstrate the spatial differences of such degradation. The inner zone of the estuary used to be highly turbid, but presently has increasing diatom (BSi) and primary production (TOC), due to lower suspended sediment concentration (SSC) in relation to dam construction. In contrast, increasing riverine dissolved inorganic nitrate (DIN) and dissolved inorganic phosphorous (DIP) input (up to 2-5 times) and decreasing DSi provide a unique setting, with an excess in N and P, which catalyzes non-diatom algae in the less-turbid middle zone of the estuary. These are reflected by decreasing BSi and BSi/TOC since the 1950s, together with an increase of TOC of 20-40%. In the outer zone of the estuary, increasing DIN, DIP, and sea surface temperatures (SSTs), have resulted in the increase of diatom biomass by 15-20% and the growth of primary production by 30-60% since the 1950s. But the drastic decrease in DSi, Si/N, and Si/P depresses the ability of diatoms to develop, resulting in a reduction of 5-10% diatom proportion (BSi/TOC) since the 1930s. This study improves the understanding of the changing estuarine ecosystem in response to global change.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA.....6144T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA.....6144T"><span>Analysing diagenetic effects of flood basalts on <span class="hlt">sedimentary</span> <span class="hlt">basins</span> during Gondwanan break-up: case studies from NW Namibia.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thompson, G. A.; Jerram, D. A.; Harris, C.; Pearson, D. G.</p> <p>2003-04-01</p> <p>ABSTRACT The eruption of <span class="hlt">large</span> volumes of lava associated with the break-up and dispersal of the Gondwana Supercontinent is a phenomenon that has been well documented in literature. The Etendeka Flood Basalt Province of NW Namibia is correlated with the Paraná Flood Basalt Province of South America and was extruded between 139Ma for the earliest flows and 130Ma for the most recent. The passive, inflated pahoehoe lava flows have preserved bedforms within sand dunes found in the Huab <span class="hlt">Basin</span> without significant deformation. This allows the internal structures of the palaeo-dunes to be analysed with great accuracy; a phenomenon rarely seen within the geological record. The sediments directly beneath, and interbedded with, the Etendeka Flood Basalt are lithostratigraphically similar to those in the Kudu Gas Province, offshore Namibia, where gas-bearing aeolian sands are interspersed with lava flows. Research by the authors is focussed on the diagenetic effects, both direct and indirect, of the emplacement of the lava, and the associated sills and dykes, on the aeolian sands. Specific interests include: the compartmentalisation of the <span class="hlt">basin</span> by sills/dykes/lava: how does this affect fluid flow paths? Diagenesis along hot contacts: is the dramatic reduction in porosity/permeability along such contacts the result of the igneous bodies alone or do they need ground water present? Can <span class="hlt">large</span> igneous events trigger the movement of hot fluids through the <span class="hlt">basin</span> and to what extent does this cause alteration to sediments? To address these issues we have identified a number of outcrop case studies within the Huab <span class="hlt">Basin</span> in NW Namibia. Here, excellent 3 dimensional outcrop coupled with almost 100 percent exposure allows detailed sampling strategies to be employed on locations of interest. In some cases igneous dykes have acted as flow barriers to pore fluids and have therefore altered the type and degree of cementation either side of the dyke. Geochemical analysis of the cement can</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFM.H12C..02B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFM.H12C..02B"><span>A Hypothetical Scenario for Full-Scale Deployment of Geological Carbon Sequestration: Investigating the Interaction Between Multiple CO2 Storage Sites in a <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Birkholzer, J.; Zhou, Q.; Jordan, P.; Tsang, C.; Leetaru, H.; Mehnert, E.; Frailey, S.; Finley, R.</p> <p>2008-12-01</p> <p>Most ongoing projects of geological carbon sequestration (GCS) are relatively small in size, with annual injection rates from a few thousand to less than a million tonnes. These projects help build the GCS technology with respect to modeling, monitoring, risk assessment, and mitigation, and have been successful so far in terms of CO2 containment and caprock geomechanical integrity. In the future, GCS will be implemented at full-scale, multiple industrial-size CO2 storage sites in <span class="hlt">large</span> <span class="hlt">sedimentary</span> <span class="hlt">basins</span> to make full use of the potential storage capacity. Simultaneous injection into multiple not-too-distant storage sites will lead to interference between the individual regions of pressure build-up and possible interference between the individual CO2 plumes. The Illinois <span class="hlt">Basin</span> is used to model the future impact of multiple injection sites in the thick, extensive Mount Simon Formation. The <span class="hlt">basin</span>-scale model domain of 241,000 km2 covers a core injection area of 24,000 km2, a larger near-field area where significant pressure buildup is expected, and an even larger far-field area for investigating environmental impacts on groundwater resources. The model assumes that there are twenty sequestration sites (spaced 30 km apart) within the core injection area. Three injection scenarios are considered, featuring annual injection rates of 5, 10, and 15 million tonnes of CO2 at each site, respectively. These scenarios correspond to 33%, 67% and 100% of the current single-point <span class="hlt">large</span> CO2 sources in the relevant states (Illinois, Indiana and Kentucky). The model adequately captures the characteristics of the Mount Simon Formation in the core injection area, which include (1) an overall thickness of 300 to 680 m, (2) an upper unit of sandstone and shale tidally influenced and deposited, (3) a thick middle unit of clean sandstone of relatively high permeability, and (4) a lower arkosic unit of higher permeability (one Darcy) with an average thickness of 90 m. At each site, CO2 is</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JAESc..67..171S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JAESc..67..171S"><span>Sequence stratigraphic significance of <span class="hlt">sedimentary</span> cycles and shell concentrations in the Aitamir Formation (Albian-Cenomanian), Kopet-Dagh <span class="hlt">Basin</span>, northeastern Iran</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sharafi, M.; Mahboubi, A.; Moussavi-Harami, R.; Ashuri, M.; Rahimi, B.</p> <p>2013-05-01</p> <p>Albian-Cenomanian siliciclastic shallow marine sediments of the Aitamir Formation, Kopet-Dagh <span class="hlt">Basin</span>, northeastern Iran, form strongly asymmetric fining-coarsening-upward cycles, which are interpreted as recording changes in relative sea level (deepening-shallowing cycles). These cycles correspond to depositional sequences, in which deposits of the lowstand systems tract are not present, the sequence boundary coinciding with the transgressive surface. Shell concentrations are found in distinct positions within the depositional sequence: as transgressive lags at the base of the transgressive systems tract (TST), in the maximum flooding zone (MFZ), and at or close to the top of the highstand systems tract (HST). They are dominated by bivalves (mainly oysters) and/or ammonites and differ from each other in a number of stratigraphic, sedimentologic, palaeoecological and taphonomic features, such as species diversity, preservation quality, orientation, percentage of disarticulation, and degree of biogenic alteration. Characteristic features of concentrations at the base of the TSTs are moderate time-averaging, distinct basal erosional surface, sorting, a chaotic to preferred convex-up orientation, and nearly total disarticulation of shells. They are suggestive of an environment in which reworking and local transport was frequent events. Similar features are shown by concentrations near the tops of the HSTs, except that the shells were <span class="hlt">largely</span> concentrated in lenses rather than in beds as in the transgressive lags. Associated <span class="hlt">sedimentary</span> structures indicate deposition above fair weather wave base in a high-energy environment. Concentrations occurring in the MFZ, in contrast, are autochthonous and highly time-averaged, having accumulated during times of low rates of sedimentation below storm wave base. This is supported by their high preservation quality (comparatively high percentage of articulated shells, shells of infaunal organisms commonly preserved in life position</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20080031650','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20080031650"><span>Previously Unrecognized <span class="hlt">Large</span> Lunar Impact <span class="hlt">Basins</span> Revealed by Topographic Data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Frey, Herbert V.</p> <p>2008-01-01</p> <p>The discovery of a <span class="hlt">large</span> population of apparently buried impact craters on Mars, revealed as Quasi- Circular Depressions (QCDs) in Mars Orbiting Laser Altimeter (MOLA) data [1,2,3] and as Circular Thin Areas (CTAs) [4] in crustal thickness model data [5] leads to the obvious question: are there unrecognized impact features on the Moon and other bodies in the solar system? Early analysis of Clementine topography revealed several <span class="hlt">large</span> impact <span class="hlt">basins</span> not previously known [6,7], so the answer certainly is "Yes." How <span class="hlt">large</span> a population of previously undetected impact <span class="hlt">basins</span>, their size frequency distribution, and how much these added craters and <span class="hlt">basins</span> will change ideas about the early cratering history and Late Heavy Bombardment on the Moon remains to be determined. Lunar Orbiter Laser Altimeter (LOLA) data [8] will be able to address these issues. As a prelude, we searched the state-of-the-art global topographic grid for the Moon, the Unified Lunar Control Net (ULCN) [9] for evidence of <span class="hlt">large</span> impact features not previously recognized by photogeologic mapping, as summarized by Wilhelms [lo].</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AGUFM.H72C0870M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AGUFM.H72C0870M"><span>Comparing Groundwater Contamination Vulnerability in <span class="hlt">Large</span>, Urbanized <span class="hlt">Basins</span> of California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Moran, J. E.; Hudson, G. B.; Leif, R.; Eaton, G. F.</p> <p>2002-12-01</p> <p>We have sampled over 700 public drinking water wells as part of a study to assess relative contamination susceptibility of the major groundwater <span class="hlt">basins</span> in California. The parameters used to rank wells according to vulnerability are groundwater age dates (using the tritium-3helium method), stable isotopes of the water molecule (for water source determination), and occurrence of low level Volatile Organic Compounds (VOCs). Long-screened production wells supply clean, high quality samples, and sample the resource that is being used. However, the groundwater age distribution from production wells may be quite broad, and comparisons to the predicted initial tritium value for the measured mean age, along with analysis of radiogenic 4Helium are used to de-convolute the mixed age. Results from the Los Angeles and Orange County <span class="hlt">Basins</span>, and Santa Clara Valley, will be presented. A <span class="hlt">large</span> volume of both imported and locally captured water is artificially recharged in these intensively managed <span class="hlt">basins</span>. An effective confining unit in the Santa Clara Valley <span class="hlt">basin</span> prevents widespread vertical transport of contaminants down to drinking water wells. In the southern California <span class="hlt">basins</span>, groundwater age and the frequency of occurrence of low-level VOCs are spatially correlated, with more recently recharged water likely to have VOC detections. 'Pre-modern' water is nearly always free of VOCs, except when a suspected 'short circuit', (e.g., loss of integrity in well casing) allows near surface contamination to reach 'old' water. Methyl-tertiary-Butyl Ether (MTBE) can be a useful time marker in groundwater <span class="hlt">basins</span>, with water recharged after the 1980's showing traces of MTBE. Water resource managers can use these vulnerability assessments to focus monitoring efforts, site new wells, plan land use, and evaluate remediation activities. This work was performed under the auspices of the U.S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015E%26PSL.432..187P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015E%26PSL.432..187P"><span><span class="hlt">Large</span> Carbonate Associated Sulfate isotopic variability between brachiopods, micrite, and other <span class="hlt">sedimentary</span> components in Late Ordovician strata</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Present, Theodore M.; Paris, Guillaume; Burke, Andrea; Fischer, Woodward W.; Adkins, Jess F.</p> <p>2015-12-01</p> <p>Carbonate Associated Sulfate (CAS) is trace sulfate incorporated into carbonate minerals during their precipitation. Its sulfur isotopic composition is often assumed to track that of seawater sulfate and inform global carbon and oxygen budgets through Earth's history. However, many CAS sulfur isotope records based on bulk-rock samples are noisy. To determine the source of bulk-rock CAS variability, we extracted CAS from different internal <span class="hlt">sedimentary</span> components micro-drilled from well-preserved Late Ordovician and early Silurian-age limestones from Anticosti Island, Quebec, Canada. Mixtures of these components, whose sulfur isotopic compositions vary by nearly 25‰, can explain the bulk-rock CAS range. <span class="hlt">Large</span> isotopic variability of <span class="hlt">sedimentary</span> micrite CAS (34S-depleted from seawater by up to 15‰) is consistent with pore fluid sulfide oxidation during early diagenesis. Specimens recrystallized during burial diagenesis have CAS 34S-enriched by up to 9‰ from Hirnantian seawater, consistent with microbial sulfate reduction in a confined aquifer. In contrast to the other variable components, brachiopods with well-preserved secondary-layer fibrous calcite-a phase independently known to be the best-preserved <span class="hlt">sedimentary</span> component in these strata-have a more homogeneous isotopic composition. These specimens indicate that seawater sulfate remained close to about 25‰ (V-CDT) through Hirnantian (end-Ordovician) events, including glaciation, mass extinction, carbon isotope excursion, and pyrite-sulfur isotope excursion. The textural relationships between our samples and their CAS isotope ratios highlight the role of diagenetic biogeochemical processes in setting the isotopic composition of CAS.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.9314M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.9314M"><span>Cosmogenic Nuclides 10Be-21Ne Burial Dating of Middle Miocene <span class="hlt">Sedimentary</span> Formation of the Hongliu Valley in Southern Ningxia <span class="hlt">Basin</span>: A Case of Isotopic Geochronology Study for the Cenozoic <span class="hlt">Sedimentary</span> Strata</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ma, Yan; Zhang, Huiping; Wang, Weitao; Pang, Jianzhang; Zheng, Dewen</p> <p>2016-04-01</p> <p>Chronology studies for the Cenozoic <span class="hlt">sedimentary</span> strata based on the magnetostratigraphy cannot afford the unique chronological sequences in the absence of absolute ages from biostratigraphy or volcanic ash chronology. In situ-produced cosmogenic nuclides provide a powerful tool for the sediment dating based on the time-dependent concentration ratio of two nuclides, which are produced in the same mineral but with different half-lives. Thereinto,10Be-26Al is the most widely used nuclide pairs, of which the available dating range spans the Plio-Pleistocene. But the coupling of 10Be with the stable nuclide 21Ne would significantly improve the burial dating range up to the middle Miocene, which is promising in revolutionizing the chronology study for the Late Cenozoic terrestrial <span class="hlt">sedimentary</span> sequences. We have applied 10Be-21Ne pair for dating the middle Miocene sediments of the Hongliu Valley in southern Ningxia <span class="hlt">basin</span>. Two major features of the sediments are involved in our study: (1) sediments originated from the steady erosion of the source area, and (2) the burial depth of our sample after deposition is time dependent due to the gradual accumulation of sediments into <span class="hlt">basin</span>. The post-burial nuclide production is estimated to be less than 3%, including the contribution by muon interactions, of the total nuclide concentrations measured in our sample. Our 10Be-21Ne analysis demonstrates the age of the burial sample is 12.4(+0.6/-0.4) Ma, and the erosion rate at the source area is 0.26±0.01 cm ka-1. The sample's burial age is consistent with the age constraint set by the Hongliugou Formation (16.7-5.4 Ma) which we collected the sample in. Vertebrate fossils of Platybelodon tongxinensis with an age between 12 and 15 Ma exhumated along with our sample further verifies the reliability of our dating results for the middle Miocene sediments.This study has shown the improved age range of cosmogenic-nuclide burial dating method by incorporating the stable nuclide 21Ne, and has</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001AGUSM...H31D01F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001AGUSM...H31D01F"><span>Anacostia River <span class="hlt">Basin</span>: <span class="hlt">Large</span>, Medium, and Small Lumps</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Feldman, A. D.; Dufour, A.; Dotson, H. W.</p> <p>2001-05-01</p> <p> constructed using the U.S. Army Corps of Engineers' Hydrologic Modeling System, HEC-HMS. HMS can simulate any-sized river <span class="hlt">basin</span> with unlimited subbasins and routing reaches. It can also simulate subbasin runoff on a gridded, semi-distributed basis. The Anacostia <span class="hlt">Basin</span> was analyzed in three levels of detail at each gauge: one subbasin, five-to-ten subbasins, and 20-to-30 subbasins. Those levels of detail serve three analysis purposes, respectively: flow-frequency at the gauge, flow frequencies at flood-damage centers in other locations, and flow frequencies throughout the <span class="hlt">basin</span> for local floodplain management. In addition to comparing simulation results for these different-sized lumps, a 4-km gridded representation of the <span class="hlt">basin</span> is compared to the <span class="hlt">large</span>, single-subbasin approach.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1818535T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1818535T"><span>Quantitative characterisation of <span class="hlt">sedimentary</span> grains</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tunwal, Mohit; Mulchrone, Kieran F.; Meere, Patrick A.</p> <p>2016-04-01</p> <p>Analysis of <span class="hlt">sedimentary</span> texture helps in determining the formation, transportation and deposition processes of <span class="hlt">sedimentary</span> rocks. Grain size analysis is traditionally quantitative, whereas grain shape analysis is <span class="hlt">largely</span> qualitative. A semi-automated approach to quantitatively analyse shape and size of sand sized <span class="hlt">sedimentary</span> grains is presented. Grain boundaries are manually traced from thin section microphotographs in the case of lithified samples and are automatically identified in the case of loose sediments. Shape and size paramters can then be estimated using a software package written on the Mathematica platform. While automated methodology already exists for loose sediment analysis, the available techniques for the case of lithified samples are limited to cases of high definition thin section microphotographs showing clear contrast between framework grains and matrix. Along with the size of grain, shape parameters such as roundness, angularity, circularity, irregularity and fractal dimension are measured. A new grain shape parameter developed using Fourier descriptors has also been developed. To test this new approach theoretical examples were analysed and produce high quality results supporting the accuracy of the algorithm. Furthermore sandstone samples from known aeolian and fluvial environments from the Dingle <span class="hlt">Basin</span>, County Kerry, Ireland were collected and analysed. Modern loose sediments from glacial till from County Cork, Ireland and aeolian sediments from Rajasthan, India have also been collected and analysed. A graphical summary of the data is presented and allows for quantitative distinction between samples extracted from different <span class="hlt">sedimentary</span> environments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMGP41A0985C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMGP41A0985C"><span>Detecting Light Hydrocarbon Microseepages and related Intra-<span class="hlt">sedimentary</span> Structures at the São Francisco <span class="hlt">Basin</span>, Brazil, using Airborne Geophysical Data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Curto, J. B.; Pires, A. C.; Silva, A.; Crosta, A. P.</p> <p>2011-12-01</p> <p>The use of indirect techniques for the detection of light hydrocarbons occurrences on the surface, named as microseepages, has been used to augment hydrocarbon exploration. Surveys developed for this type of application are normally targeted at mapping the effects that microseepages cause on the environment. In Brazil, most available airborne geophysical surveys were not appropriately designed for this type of application and, thus far they have been mostly used to define the main <span class="hlt">basin</span> structural features. Existing microseepages are known in Remanso do Fogo area (Minas Gerais State, Brazil), located in São Francisco <span class="hlt">Basin</span>, where the Quaternary <span class="hlt">sedimentary</span> cover made the identification of new occurrences and associated controlling structures quite difficult. This study investigates the spatial distribution of hydrocarbon related structures in shallower to intra-<span class="hlt">sedimentary</span> depths in the Remanso do Fogo area, using airborne magnetic and gamma-ray spectrometry data. These data were managed by the ANP (Brazilian Petroleum National Agency) and conducted by Lasa Engineering & Surveys in 2006. In the study area, data were acquired along north-south flight lines spaced 500 m apart and along orthogonal tie lines flown 4 Km apart at a terrain clearance of 100 m. The geophysical data were processed using techniques developed to suppress the influence of regional geological signatures. For the magnetic data, this study focuses on the enhancement of intra-<span class="hlt">sedimentary</span> structures and possible near surface accumulations of diagenetic magnetic minerals, provided by hydrocarbon related chemical reactions. The amplitude of the analytic signal, calculated with second order derivatives, combined with the total horizontal gradient of the subtraction between the 1200 and 400 meter upward continuations, illuminated the NW and EW magnetic lineaments, which are partially related to the microseepages and the drainage of the area. The distinction of near-surface and deeper signatures also</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JAESc.115...97D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JAESc.115...97D"><span>Spreading dynamics and <span class="hlt">sedimentary</span> process of the Southwest Sub-<span class="hlt">basin</span>, South China Sea: Constraints from multi-channel seismic data and IODP Expedition 349</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ding, Weiwei; Li, Jiabiao; Clift, Peter D.</p> <p>2016-01-01</p> <p>Neotectonic and <span class="hlt">sedimentary</span> processes in the South China Sea abyssal <span class="hlt">basin</span> are still debated because of the lack of drilling evidence to test competing models. In this study, we interpreted four multi-channel seismic profiles across the Southwest Sub-<span class="hlt">basin</span> (SWSB) and achieved stratigraphic correlation with new drilling data from Integrated Ocean Discovery Program (IODP) Expedition 349. Neogene sediments are divided into four stratigraphic units, each with distinctive seismic character. Sedimentation rate and lithology variations suggest climate-controlled sedimentation. In the late Miocene winter monsoon strength and increased aridity in the limited accumulation rates in the SWSB. Since the Pliocene summer monsoons and a variable glacial-interglacial climate since have enhanced accumulation rates. Terrigeneous sediments in the SWSB are most likely derived from the southwest. Three basement domains are classified with different <span class="hlt">sedimentary</span> architectures and basement structures, including hyper-stretched crust, exhumed subcontinental mantle, and steady state oceanic crust. The SWSB has an asymmetric geometry and experienced detachment faulting in the final stage of continental rifting and exhumation of continental mantle lithosphere. Mantle lithospheric breakup post-dates crustal separation, delaying the establishment of oceanic spreading and steady state crust production.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.1740D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.1740D"><span>Spreading Dynamics and <span class="hlt">Sedimentary</span> Process of the Southwest Sub-<span class="hlt">basin</span>, South China Sea: Constraints from multi-channel seismic data and IODP Expedition 349</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ding, Weiwei; Li, Jiabiao; Clift, Peter</p> <p>2016-04-01</p> <p>Neotectonic and <span class="hlt">sedimentary</span> processes in the South China Sea abyssal <span class="hlt">basin</span> are still debated because of the lack of drilling evidence to test competing models. In this study, we interpreted four multi-channel seismic profiles across the Southwest Sub-<span class="hlt">basin</span> (SWSB) and achieved stratigraphic correlation with new drilling data from Integrated Ocean Discovery Program (IODP) Expedition 349. Neogene sediments are divided into four stratigraphic units, each with distinctive seismic character. Sedimentation rate and lithology variations suggest climate-controlled sedimentation. In the late Miocene winter monsoon strength and increased aridity in the limited accumulation rates in the SWSB. Since the Pliocene summer monsoons and a variable glacial-interglacial climate since have enhanced accumulation rates. Terrigeneous sediments in the SWSB are most likely derived from the southwest. Three basement domains are classified with different <span class="hlt">sedimentary</span> architectures and basement structures, including hyper-stretched crust, exhumed subcontinental mantle, and steady state oceanic crust. The SWSB has an asymmetric geometry and experienced detachment faulting in the final stage of continental rifting and exhumation of continental mantle lithosphere. Mantle lithospheric breakup post-dates crustal separation, delaying the establishment of oceanic spreading and steady state crust production.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/20062587','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/20062587"><span>Structure of the lithosphere and Mesozoic <span class="hlt">sedimentary</span> <span class="hlt">basins</span> in western Liaoning, northern Liaoning, and Songliao, northeast China</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Xu, M.; Middleton, M.F.; Xue, L.F.; Wang, D.P.</p> <p>2000-03-01</p> <p>The western Liaoning, northern Liaoning, and Songliao areas represent three different tectonic units with different lithosphere thermal-mechanical properties in terms of composition, thickness of the thermal lithosphere, effective elastic thickness, depth of the detachment surface, and strength of the lithosphere. Western Liaoning is characterized by a thick lithosphere with high rigidity and strength, whereas Songliao and northern Liaoning are characterized by relatively thin lithosphere with low rigidity and strength. These differences controlled the development of distinct types of <span class="hlt">basins</span> under an extensional regime during the Early Cretaceous. The <span class="hlt">basins</span> in western Liaoning are controlled by faulting rather than by thermal subsidence. The Songliao <span class="hlt">basin</span> in controlled both by faulting and by thermal subsidence, and thus both syn- and post-rift sequences developed with the same thickness in the center of the <span class="hlt">basin</span>. In contrast, in northern Liaoning, the <span class="hlt">basins</span> are mainly controlled by faulting, and to a lesser extent by subsequent thermal subsidence. As a part of east China, where more than 93% of the proven oil reserves of China are distributed, the western Liaoning-northern Liaoning-Songliao area also has attracted considerable attention for this hydrocarbon potential. The Songliao <span class="hlt">basin</span> is proven to be the largest non-marine petroliferous <span class="hlt">basin</span> and one of the most important oil- and gas-producing <span class="hlt">basins</span> in China. In addition, the Tieling-Changtu <span class="hlt">basin</span> and the Zhezhong depression in northern Liaoning show some petroleum potential. In contrast, <span class="hlt">basins</span> in western Liaoning represent a limited prospect for oil and gas.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1611845S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1611845S"><span>Buried paleo-<span class="hlt">sedimentary</span> <span class="hlt">basins</span> in the north-eastern Black Sea-Azov Sea area and tectonic implications (DOBRE-2)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Starostenko, Vitaly; Stephenson, Randell; Janik, Tomasz; Tolkunov, Anatoly</p> <p>2014-05-01</p> <p>A number of independent but inter-related projects carried out under the auspices of various national and international programmes in Ukraine including DARIUS were aimed at imaging the upper lithosphere, crustal and <span class="hlt">sedimentary</span> <span class="hlt">basin</span> architecture in the north-eastern Black Sea, southern Crimea and Kerch peninsulas and the Azov Sea. This region marks the transition from relatively undisturbed Precambrian European cratonic crust and lithosphere north of the Azov Sea to areas of significant Phanerozoic tectonics and <span class="hlt">basin</span> development, in both extensional as well as compressional environments, to the south, including the eastern Black Sea rift, which is the main <span class="hlt">sedimentary</span> <span class="hlt">basin</span> of the study area. The wide-angle reflection and refraction (WARR) profile DOBRE-2, a Ukrainian national project with international participation (see below), overlapping some 115 km of the southern end of the DOBREfraction'99 profile (that crosses the intracratonic Donbas Foldbelt) in the north and running to the eastern Black Sea <span class="hlt">basin</span> in the south, utilised on- and offshore recording and energy sources. It maps crustal velocity structure across the craton margin and documents, among other things, that the Moho deepens from 40 km to ~47 km to the southwest below the Azov Sea and Crimean-Caucasus deformed zone. A regional CDP seismic profile coincident with DOBRE-2, crossing the Azov Sea, Kerch Peninsula and the north-eastern Black Sea southwest to the Ukraine-Turkey border, acquired by Ukrgeofisika (the Ukrainian national geophysical company) reveals in its inferred structural relationships the ages of Cretaceous and younger extensional and subsequent <span class="hlt">basin</span> inversion tectonic events as well as the 2D geometry of basement displacement associated with post mid-Eocene inversion. A direct comparison of the results of the WARR velocity model and the near-vertical reflection structural image has been made by converting the former into the time domain. The results dramatically demonstrate that</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1994Tecto..13..917K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1994Tecto..13..917K"><span>Paleomagnetism of baked <span class="hlt">sedimentary</span> rocks in the Newark and Culpeper <span class="hlt">basins</span>: Evidence for the J1 cusp and significant Late Triassic apparent polar wander from the Mesozoic <span class="hlt">basins</span> of North America</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kodama, Kenneth P.; Cioppa, Maria T.; Sherwood, Elizabeth; Warnock, Andrew C.</p> <p>1994-08-01</p> <p>A paleomagnetic study of 14 sites in the baked <span class="hlt">sedimentary</span> rocks of the Newark <span class="hlt">basin</span> Passaic Formation in southeastern Pennsylvania reveals two types of magnetic behavior. Dark gray-colored, baked <span class="hlt">sedimentary</span> rocks have peak unblocking temperatures of 640°C, high magnetic intensities, and shallow, normal polarity, northeasterly directions. Light gray-colored rocks have peak unblocking temperatures of less than 580°C, low magnetic intensities, and intermediate inclination, normal polarity, northwesterly directions. The low unblocking temperature magnetizations are secondary magnetizations which have declinations similar to but are shallower than the B remagnetization observed by Witte and Kent (1991) throughout the Newark <span class="hlt">basin</span>. The discrepancy may be due to "underprinting" by an unresolved primary magnetization. The low unblocking temperature magnetization was probably acquired by growth of secondary magnetite during a hydrothermal event, as postulated by Sutter (1988), based on geochronologic data. The high unblocking temperature magnetization is significantly prefolding. Both the low-peak unblocking temperature magnetization and the high-peak unblocking temperature magnetization suggest a 15° counterclockwise block rotation of the Sassamansville syncline. If this rotation is removed from the high unblocking temperature sites collected around the fold, a stronger passage of the fold test results. Six sites were also collected from baked sediments and one site from diabase in northern Virginia's Culpeper <span class="hlt">basin</span>, since Sutter's geochronological work indicated that the intrusives in the Culpeper <span class="hlt">basin</span> are coeval to the Newark <span class="hlt">basin</span> intrusives. Virtual geomagnetic poles (VGPs), based on the tilt-corrected, high-temperature Newark <span class="hlt">basin</span> magnetizations, were compared with the VGPs calculated from the site means of a high-temperature magnetization isolated from baked <span class="hlt">sedimentary</span> rocks in the Culpeper <span class="hlt">basin</span> and to the magnetizations reported by Raymond (1982) from dikes</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20080030212','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20080030212"><span>Mars Crustal Dichotomy: <span class="hlt">Large</span> Lowland Impact <span class="hlt">Basins</span> may have Formed in Pre-Thinned Crust</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Frey, H. V.</p> <p>2008-01-01</p> <p>Crater retention ages of <span class="hlt">large</span> impact <span class="hlt">basins</span> on Mars suggest most formed in a relatively short time, perhaps in less than 200 million years. <span class="hlt">Large</span> <span class="hlt">basins</span> in the lowlands have thinner central regions than similar size <span class="hlt">basins</span> in the highlands. <span class="hlt">Large</span> lowland impact <span class="hlt">basins</span>, which we previously suggested might explain the low topography and thin crust of the northern part of Mars, may have formed in crust already thinned by yet earlier processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoJI.204....1S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoJI.204....1S"><span>Seismic velocities within the <span class="hlt">sedimentary</span> succession of the Canada <span class="hlt">Basin</span> and southern Alpha-Mendeleev Ridge, Arctic Ocean: evidence for accelerated porosity reduction?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shimeld, John; Li, Qingmou; Chian, Deping; Lebedeva-Ivanova, Nina; Jackson, Ruth; Mosher, David; Hutchinson, Deborah</p> <p>2016-01-01</p> <p>The Canada <span class="hlt">Basin</span> and the southern Alpha-Mendeleev ridge complex underlie a significant proportion of the Arctic Ocean, but the geology of this undrilled and mostly ice-covered frontier is poorly known. New information is encoded in seismic wide-angle reflections and refractions recorded with expendable sonobuoys between 2007 and 2011. Velocity-depth samples within the <span class="hlt">sedimentary</span> succession are extracted from published analyses for 142 of these records obtained at irregularly spaced stations across an area of 1.9E + 06 km2. The samples are modelled at regional, subregional and station-specific scales using an exponential function of inverse velocity versus depth with regionally representative parameters determined through numerical regression. With this approach, smooth, non-oscillatory velocity-depth profiles can be generated for any desired location in the study area, even where the measurement density is low. Practical application is demonstrated with a map of <span class="hlt">sedimentary</span> thickness, derived from seismic reflection horizons interpreted in the time domain and depth converted using the velocity-depth profiles for each seismic trace. A thickness of 12-13 km is present beneath both the upper Mackenzie fan and the middle slope off of Alaska, but the <span class="hlt">sedimentary</span> prism thins more gradually outboard of the latter region. Mapping of the observed-to-predicted velocities reveals coherent geospatial trends associated with five subregions: the Mackenzie fan; the continental slopes beyond the Mackenzie fan; the abyssal plain; the southwestern Canada <span class="hlt">Basin</span>; and, the Alpha-Mendeleev magnetic domain. Comparison of the subregional velocity-depth models with published borehole data, and interpretation of the station-specific best-fitting model parameters, suggests that sandstone is not a predominant lithology in any of the five subregions. However, the bulk sand-to-shale ratio likely increases towards the Mackenzie fan, and the model for this subregion compares favourably with</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70176638','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70176638"><span>Seismic velocities within the <span class="hlt">sedimentary</span> succession of the Canada <span class="hlt">Basin</span> and southern Alpha-Mendeleev Ridge, Arctic Ocean: evidence for accelerated porosity reduction?</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Shimeld, John; Li, Qingmou; Chian, Deping; Lebedeva-Ivanova, Nina; Jackson, Ruth; Mosher, David; Hutchinson, Deborah R.</p> <p>2016-01-01</p> <p>The Canada <span class="hlt">Basin</span> and the southern Alpha-Mendeleev ridge complex underlie a significant proportion of the Arctic Ocean, but the geology of this undrilled and mostly ice-covered frontier is poorly known. New information is encoded in seismic wide-angle reflections and refractions recorded with expendable sonobuoys between 2007 and 2011. Velocity–depth samples within the <span class="hlt">sedimentary</span> succession are extracted from published analyses for 142 of these records obtained at irregularly spaced stations across an area of 1.9E + 06 km2. The samples are modelled at regional, subregional and station-specific scales using an exponential function of inverse velocity versus depth with regionally representative parameters determined through numerical regression. With this approach, smooth, non-oscillatory velocity–depth profiles can be generated for any desired location in the study area, even where the measurement density is low. Practical application is demonstrated with a map of <span class="hlt">sedimentary</span> thickness, derived from seismic reflection horizons interpreted in the time domain and depth converted using the velocity–depth profiles for each seismic trace. A thickness of 12–13 km is present beneath both the upper Mackenzie fan and the middle slope off of Alaska, but the <span class="hlt">sedimentary</span> prism thins more gradually outboard of the latter region. Mapping of the observed-to-predicted velocities reveals coherent geospatial trends associated with five subregions: the Mackenzie fan; the continental slopes beyond the Mackenzie fan; the abyssal plain; the southwestern Canada <span class="hlt">Basin</span>; and, the Alpha-Mendeleev magnetic domain. Comparison of the subregional velocity–depth models with published borehole data, and interpretation of the station-specific best-fitting model parameters, suggests that sandstone is not a predominant lithology in any of the five subregions. However, the bulk sand-to-shale ratio likely increases towards the Mackenzie fan, and the model for this subregion compares</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26658165','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26658165"><span>1.8 Billion Years of Detrital Zircon Recycling Calibrates a Refractory Part of Earth's <span class="hlt">Sedimentary</span> Cycle.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hadlari, Thomas; Swindles, Graeme T; Galloway, Jennifer M; Bell, Kimberley M; Sulphur, Kyle C; Heaman, Larry M; Beranek, Luke P; Fallas, Karen M</p> <p>2015-01-01</p> <p>Detrital zircon studies are providing new insights on the evolution of <span class="hlt">sedimentary</span> <span class="hlt">basins</span> but the role of <span class="hlt">sedimentary</span> recycling remains <span class="hlt">largely</span> undefined. In a broad region of northwestern North America, this contribution traces the pathway of detrital zircon sand grains from Proterozoic sandstones through Phanerozoic strata and argues for multi-stage <span class="hlt">sedimentary</span> recycling over more than a billion years. As a test of our hypothesis, integrated palynology and detrital zircon provenance provides clear evidence for erosion of Carboniferous strata in the northern Cordillera as a sediment source for Upper Cretaceous strata. Our results help to calibrate Earth's <span class="hlt">sedimentary</span> cycle by showing that recycling dominates <span class="hlt">sedimentary</span> provenance for the refractory mineral zircon.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.T31A2141L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.T31A2141L"><span>We are in need of sampling the <span class="hlt">sedimentary</span> cover and bedrock in the Amerasia <span class="hlt">Basin</span>. (Suggested site locations in the Makarov <span class="hlt">Basin</span>, the Mendeleev and Lomonosov ridges and adjacent areas.)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lebedeva-Ivanova, N. N.</p> <p>2010-12-01</p> <p>The Amerasia <span class="hlt">Basin</span> has a complex origin; alone, the geophysical data can support very different hypotheses. For understanding the tectonic evolution of the <span class="hlt">Basin</span> and origin of the ridges and troughs it is important to collect geological samples. Based on analyzed seismic data (NP-28 and 26, HOTRAX, Arctic-2000 and TransArctic) over the Makarov <span class="hlt">Basin</span>, the Mendeleev and Lomonosov ridges and adjacent areas, numbers of key drill sites are proposed. All proposed sites in combinations with other geophysical research of the area are fit well with most of the Site Survey Data Requirements (IODP) for a drilling site. Bedrock samples from key locations are especially needed, with full video or photo documentation of the sampling for avoiding later debates about whether bedrock or ice-drift was collected. Due to close locations to a sea bottom, bedrock can be sampled by gravity piston-cores or shallow drilling. Full stratigraphic sections though the Cenozoic and older <span class="hlt">sedimentary</span> successions are needed at other proposed key locations for understanding the tectonic evolution of the Amerasia <span class="hlt">Basin</span>. The depositional environment of the key reflections related to Cenozoic shallow water environments, as recorded in the ACEX drillholes, needs to be investigated in other locations. We will then be able to define better the nature of particular morphological features and construct more reliable tectonic models of the Amerasia <span class="hlt">Basin</span>, in general.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1177424','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1177424"><span>CO<sub>2</sub> Saline Storage Demonstration in Colorado <span class="hlt">Sedimentary</span> <span class="hlt">Basins</span>. Applied Studies in Reservoir Assessment and Dynamic Processes Affecting Industrial Operations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Nummedal, Dag; Doran, Kevin; Sitchler, Alexis; McCray, John; Mouzakis, Katherine; Glossner, Andy; Mandernack, Kevin; Gutierrez, Marte; Pranter, Matthew; Rybowiak, Chris</p> <p>2012-09-30</p> <p>This multitask research project was conducted in anticipation of a possible future increase in industrial efforts at CO<sub>2</sub> storage in Colorado <span class="hlt">sedimentary</span> <span class="hlt">basins</span>. Colorado is already the home to the oldest Rocky Mountain CO<sub>2</sub> storage site, the Rangely Oil Field, where CO<sub>2</sub>-EOR has been underway since the 1980s. The Colorado Geological Survey has evaluated storage options statewide, and as part of the SW Carbon Sequestration Partnership the Survey, is deeply engaged in and committed to suitable underground CO<sub>2</sub> storage. As a more sustainable energy industry is becoming a global priority, it is imperative to explore the range of technical options available to reduce emissions from fossil fuels. One such option is to store at least some emitted CO<sub>2</sub> underground. In this NETL-sponsored CO<sub>2</sub> sequestration project, the Colorado School of Mines and our partners at the University of Colorado have focused on a set of the major fundamental science and engineering issues surrounding geomechanics, mineralogy, geochemistry and reservoir architecture of possible CO<sub>2</sub> storage sites (not limited to Colorado). Those are the central themes of this final report and reported below in Tasks 2, 3, 4, and 6. Closely related to these reservoir geoscience issues are also legal, environmental and public acceptance concerns about pore space accessibility—as a precondition for CO<sub>2</sub> storage. These are addressed in Tasks 1, 5 and 7. Some debates about the future course of the energy industry can become acrimonius. It is true that the physics of combustion of hydrocarbons makes it impossible for fossil energy to attain a carbon footprint anywhere nearly as low as that of renewables. However, there are many offsetting benefits, not the least that fossil energy is still plentiful, it has a global and highly advanced distribution system in place, and the footprint that the fossil energy infrastructure occupies is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.B23B1270B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.B23B1270B"><span>Assessing the Impact of Floodplains in <span class="hlt">Sedimentary</span> Transport in the Amazon <span class="hlt">Basin</span> Using the Chemistry of Riverine Suspended Load and Bedload</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bouchez, J.; Gaillardet, J.</p> <p>2007-12-01</p> <p><span class="hlt">Large</span> rivers integrate over time and space the geologic events affecting their catchment. But, as dynamic systems, they also have their own characteristic time-scale. <span class="hlt">Large</span> rivers such as the Amazon are thus likely to record important geologic events such as glacial-interglacial alternance or tectonic uplift. It has been demonstrated by several independent methods that most of the Earth's largest rivers are not eroding at steady-state, exporting amounts of material different from what has been inferred from chemical, geomorphological and tectonic studies. Floodplains can act as major sediments export filters, and could be one of the systems making rivers not to erode continents at steady-state. Nevertheless, the exact impact on riverine <span class="hlt">sedimentary</span> storage and transfer, as well on weathering, are still a matter of debate. To assess the impact of floodplains, we propose a simple model for the Amazon <span class="hlt">basin</span> main rivers (Amazon, Madeira and Solimões), based on the inversion of data on total and elemental riverine fluxes. This inversion method has been widely used (e.g. in Gaillardet et al., 1999) to solve geochemical issues. From the assumption of an equilibrium between erosion in the Andes, floodplain deposition/erosion, and export by the river, a set of equations is obtained and inverted, the most <span class="hlt">largely</span> unknown parameters being deposition/erosion in floodplains and the bedload export flux. The inversion method will allow to better constrain these fluxes. A priori values are needed for all the parameters of the equations, as well as for their uncertainties. Particulate and elemental fluxes are estimated through integration of particulate concentration and composition, and water velocity and composition, over the water column of the rivers near their mouth. The chemical composition of the floodplain river sediments is constrained by the litterature (e.g. by Martinelli et al., 1993) and by correlations obtained on analyzed suspended sediments and bedload sands of the</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JGeo...77..158G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JGeo...77..158G"><span>Tectono-<span class="hlt">sedimentary</span> evolution of the peripheral <span class="hlt">basins</span> of the Alboran Sea in the arc of Gibraltar during the latest Messinian-Pliocene</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Guerra-Merchán, Antonio; Serrano, Francisco; Hlila, Rachid; El Kadiri, Khalil; Sanz de Galdeano, Carlos; Garcés, Miguel</p> <p>2014-07-01</p> <p>In the peripheral <span class="hlt">basins</span> of the Alboran Sea, five stratigraphic units (latest Messinian-Pliocene) separated by discontinuities and representing transgressive-regressive cycles have been recognized. The first unit (LM) is latest Messinian in age and precisely characterizes the Lago-Mare event at the end of the Messinian Salinity Crisis, i.e. just before the opening of the Strait of Gibraltar at the beginning of the Pliocene. The three following units (Pl-1, Pl-2 and Pl-3) are Zanclean in age, whereas the last one (Pl-4) is Piacenzian. These four Pliocene units consist of alluvial, deltaic, and littoral deposits in the marginal areas, changing to open marine deposits with planktonic components in the <span class="hlt">basinal</span> areas, although their extension varies in each <span class="hlt">basin</span>. Regionally, these units do not necessarily stack in a single stratigraphic succession because of tectonics that controlled their hosting <span class="hlt">basins</span>. Thus, the LM and Pl-1 units occur only in the Malaga and Estepona-Marbella <span class="hlt">basins</span>, revealing that the onset of the sedimentation after the Messinian evaporitic stage and the Pliocene transgression was not a single and synchronous event in the western Alboran Sea. Moreover, the Pl-3 and Pl-4 units do not appear in all <span class="hlt">basins</span>, so that the subsequent continentalization process of these Alboran peripheral areas during the Pliocene was also diachronous. The <span class="hlt">sedimentary</span> evolution of the peripheral <span class="hlt">basins</span> was controlled mainly by tectonics. During the latest Messinian-early Pliocene, the sedimentation took place in a context marked by a NNW-SSE compression and ENE-WSW perpendicular tension. The onset of the sedimentation (LM and Pl-1 units) could be linked to preexisting E-W faults that mark part of the borders of the Malaga <span class="hlt">basin</span> and the Estepona-Marbella sector. During the deposition of the Pl-2 unit, the movements of E-W, NW-SE, and NE-SW normal faults determined a continuous subsidence in several <span class="hlt">basins</span>, resulting in the accumulation of thick clastic marine sequences (i</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AGUSM.H42C..03M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AGUSM.H42C..03M"><span><span class="hlt">Large</span>-scale <span class="hlt">Sedimentary</span> Structures and Contaminant Transport: an Example from Cape Cod, Massachusetts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mulligan, A.; Uchupi, E.</p> <p>2002-05-01</p> <p>A review of 289 borehole logs collected across Cape Cod reveals that two <span class="hlt">large</span> glacial lakes once covered the peninsula. The older lake, which existed about 19,000 years ago, covered the east-west portion of Cape Cod and deposited clay, silt, and very fine sand across the area. The southern dam of this lake ultimately failed and <span class="hlt">large</span> drainage channels were carved into the surface of the glaciolacustrine sediments. These eroded lake deposits were subsequently buried by the outwash plains of sand and gravel that make up the surficial geology of today. One of the major drainage channels in the lake deposit surface is located below the Massachusetts Military Reservation (MMR), a 34 square mile facility with >10 known groundwater contaminant plumes. We will present preliminary evidence that the buried paleochannel is exerting a strong control on the transport of several plumes at MMR and thus are critical stratigraphic structures that must be understood and delineated. Although fine-grained sediments are described in borehole logs from the MMR, infering the origin and significance of these deposits is made difficult by local-scale heterogeneities. The existence of the proglacial lake and the extensive, deep drainage channels are only apparent from investigating borehole data across a larger scale. This work illustrates the importance of characterizing the stratigraphic framework beyond the confines of a specific contamination site and further shows the controls that paleochannels filled with high permeability sediments can exert on flow and transport.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/7013219','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/7013219"><span>Application of the Glossifungites ichnofacies to the recognition of sequence stratigraphic boundaries: Examples from the Cretaceous of the Western Canada <span class="hlt">sedimentary</span> <span class="hlt">basin</span>, Alberta, Canada</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Maceachern, J.A.; Pemberton, S.G.; Raychaudhuri, I.; Vossler, S. )</p> <p>1991-03-01</p> <p>The Glossifungites ichnofacies is a substrate-controlled assemblage of trace fossils, characterized by sharp-walled, unlined, passively filled, vertical to subvertical domichnia, excavated into semiconsolidated (firmground) substrates. In Cretaceous siliciclastic rocks of the Western Canada <span class="hlt">sedimentary</span> <span class="hlt">basin</span>, the assemblage is dominated by the ichnogenera Diplocraterion, Skolithos, Arenicolites, Thalassinoides, and Rhizocorallium. The Glossifungites assemblage demarcates discontinuity surfaces that reflect pauses in sedimentation accompanied by erosion. Colonization of erosionally exhumed substrates and excavation of domiciles occur predominantly within marine to marginal marine settings. In the subsurface of Alberta, several of these discontinuity surfaces correspond to important sequence stratigraphic boundaries. Caution must be employed when applying these discontinuity surfaces to regional stratigraphic problems. These surfaces can also develop in response to autocyclic processes including tidal channel migration and episodic storm erosion. Consequently, the sequence stratigraphic significance of Glossifungites-demarcated discontinuity surfaces can only be resolved through detailed regional mapping.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70155921','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70155921"><span>Tectonic and <span class="hlt">sedimentary</span> linkages between the Belt-Purcell <span class="hlt">basin</span> and southwestern Laurentia during the Mesoproterozoic ca. 1.60-1.40 Ga</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Jones, James V.; Dainel, Christohper G; Doe, Michael F</p> <p>2015-01-01</p> <p>Mesoproterozoic <span class="hlt">sedimentary</span> <span class="hlt">basins</span> in western North America provide key constraints on pre-Rodinia craton positions and interactions along the western rifted margin of Laurentia. One such <span class="hlt">basin</span>, the Belt-Purcell <span class="hlt">basin</span>, extends from southern Idaho into southern British Columbia and contains a >18-km-thick succession of siliciclastic sediment deposited ca. 1.47–1.40 Ga. The ca. 1.47–1.45 Ga lower part of the succession contains abundant distinctive non-Laurentian 1.61–1.50 Ga detrital zircon populations derived from exotic cratonic sources. Contemporaneous metasedimentary successions in the southwestern United States–the Trampas and Yankee Joe <span class="hlt">basins</span> in Arizona and New Mexico–also contain abundant 1.61–1.50 Ga detrital zircons. Similarities in depositional age and distinctive non-Laurentian detrital zircon populations suggest that both the Belt-Purcell and southwestern successions record <span class="hlt">sedimentary</span> and tectonic linkages between western Laurentia and one or more cratons including North Australia, South Australia, and (or) East Antarctica. At ca. 1.45 Ga, both the Belt-Purcell and southwest successions underwent major sedimentological changes, with a pronounced shift to Laurentian provenance and the disappearance of the 1.61–1.50 Ga detrital zircon. Upper Belt-Purcell strata contain strongly unimodal ca. 1.73 Ga detrital zircon age populations that match the detrital zircon signature of Paleoproterozoic metasedimentary rocks of the Yavapai province to the south and southeast. We propose that the shift at ca. 1.45 Ga records the onset of orogenesis in southern Laurentia coeval with rifting along its northwestern margin. Bedrock uplift associated with orogenesis and widespread, coeval magmatism caused extensive exhumation and erosion of the Yavapai province ca. 1.45–1.36 Ga, providing a voluminous and areally extensive sediment source–with suitable zircon ages–during upper Belt deposition. This model provides a comprehensive and integrated view of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000CoMP..139..748L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000CoMP..139..748L"><span>Melt inclusions in detrital spinel from the SE Alps (Italy-Slovenia): a new approach to provenance studies of <span class="hlt">sedimentary</span> <span class="hlt">basins</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lenaz, Davide; Kamenetsky, Vadim S.; Crawford, Anthony J.; Princivalle, Francesco</p> <p></p> <p>Detrital spinel is a widespread heavy mineral in sandstones from the Maastrichtian-Middle Eocene <span class="hlt">sedimentary</span> <span class="hlt">basins</span> in the SE Alps. Chemistry of detrital spinels from the Claut/Clauzetto and Julian <span class="hlt">Basins</span> (N Italy and NW Slovenia) is used to constrain petrological and geochemical affinities and tectonic provenance of the source rocks. In addition, we have analysed melt inclusion compositions in the detrital volcanic spinels to better constrain the nature of their parental magmas. This is the first study of melt inclusions in detrital spinels. Two principal compositional groups of detrital spinels are recognised based on their TiO2 and Fe2+/Fe3+; one derived from peridotites, the other from basaltic volcanics. Peridotitic spinels are more abundant and have TiO2<0.2wt% and high Cr/Cr+Al (40-90), characteristic of suprasubduction zone harzburgites. Significant chemical variations among volcanic spinels (TiO2 up to 3wt%, Al2O3 12-44wt%) suggest multiple sources, with geochemically distinct characteristics, including MORB-type and backarc <span class="hlt">basin</span> basalts, subduction-related magmas and tholeiites produced during early continental rifting. Compositions of homogenised melt inclusions in spinels with TiO2>0.2 better distinguish the differences between the compositions of their host spinels and help to further clarify the geodynamic provenance of extrusive source rocks. Several compositional groups of melt inclusions have been recognised and represent diverse magmatism of marginal <span class="hlt">basins</span>, including MORB- and subduction-related geochemical types, as well as magmas characteristic of early continental rifting. These results, combined with the data on regional ophiolitic complexes and tectonic reconstructions favour the Internal Dinarides of Yugoslavia as a possible source area for the SE Alps sediments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFMPP11B1311Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFMPP11B1311Z"><span><span class="hlt">Sedimentary</span> environments for the massive formation of the lacustrine organic rich petroleum source rocks of late Cretaceous from Songliao <span class="hlt">Basin</span>, China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhiguang, S.</p> <p>2009-12-01</p> <p>Songliao <span class="hlt">Basin</span> is the major oil-bearing and production <span class="hlt">basin</span> in China and containing two major sets of excellent organic matter rich source rocks developed during the two related short periods of later Cretaceous time. For a long time, these source rocks were considered unquestionably being formed under fresh or brackish lacustrine environment. However, increasing evidence and studies suggest that this may be not the case anymore, as possible marine transgression and much high salinity lacustrine environment has been suggested or implied from a number of recent studies for Songliao <span class="hlt">Basin</span>. Here, we show our recent extensive organic geochemical studies carried out on the core samples of Nenjiang formation from a newly drilled scientific exploration well of No. 1 in Songliao <span class="hlt">Basin</span>. The overall evidence of organic matter and biomarkers suggest that: 1) the main source rocks were likely formed under a much saline(even mesosaline) lacustrine environment, as the existence of a number high saline related biomarkers and their ratios such Pr/Ph, MTTCI, α-MTTC/δ-MTTC, α-MTTC /γ-MTTC, Gammacerane/C30hop are in favor of a mesosaline to saline environments; 2) during the major source rocks formation periods, a photic zone oxygen depletion and stratified water column was suggested by the strong occurrence of a series of aryl isoprenoids and Isorenieratane; 3) a general mild to strong reduced <span class="hlt">sedimentary</span> environments were concluded from the consistent of a number of index. Fig 1 Correlation between MTTCI vs Pr/Ph ratios with indication of salinity fields (after SCHWARK et al., 1998)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SedG..344..175T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SedG..344..175T"><span><span class="hlt">Sedimentary</span> record of seismic events in the Eocene Green River Formation and its implications for regional tectonics on lake evolution (Bridger <span class="hlt">Basin</span>, Wyoming)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Törő, Balázs; Pratt, Brian R.</p> <p>2016-10-01</p> <p>Outcrops and cores from the top of the lacustrine Tipton Member and the base of the Wilkins Peak Member ( 51.5 Ma) of the Eocene Green River Formation, Bridger <span class="hlt">Basin</span> in southwestern Wyoming yield a wide variety of <span class="hlt">sedimentary</span> deformation features many of which are laterally extensive for more than 50 km. They include various types of folds, load structures, pinch-and-swell structures, microfaults, breccias and <span class="hlt">sedimentary</span> dikes. In most cases deformation is represented by hybrid brittle-ductile structures exhibiting lateral variation in deformation style. These occur in low-energy, profundal organic-rich carbonate mudstones (oil shales), trona beds, tuffs, and profundal to sublittoral silty carbonate deposited in paleolake Gosiute. The deformation is not specific to the depositional environment because <span class="hlt">sedimentary</span> units stratigraphically higher with similar facies show no deformation. The studied interval lacks any evidence for possible trigger mechanisms intrinsic to the depositional environment, such as strong wave action, rapid sediment loading, evaporite dissolution and collapse, or desiccation, so 'endogenic' causes are ruled out. Thus, the deformation features are interpreted as seismites, and change in deformation style and inferred increase in intensity towards the south suggest that the earthquakes were sourced from the nearby Uinta Fault System. The 22 levels exhibiting seismites recognized in cores indicate earthquakes with minimum magnitudes between 6 and 7, minimum epicentral intensity (MCS) of 9, and varying recurrence intervals in the seismic history of the Uinta Fault System, with a mean apparent recurrence period of 8.1 k.y. using average sedimentation rates and dated tuffs; in detail, however, there are two noticeably active periods followed by relative quiescence. The stratigraphic position of these deformed intervals also marks the transition between two distinct stages in lake evolution, from the balanced-filled Tipton Member to the overlying</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JAfES..95...77C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JAfES..95...77C"><span>Stratigraphic architecture and forcing processes of the late Neogene Miradouro da Lua <span class="hlt">sedimentary</span> prism, Cuanza <span class="hlt">Basin</span>, Angola</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cauxeiro, C.; Durand, J.; Lopez, M.</p> <p>2014-07-01</p> <p>The Miradouro da Lua cliffs, which are 60 km south of Luanda, record the building and uplift of the late Neogene Palaeo-Cuanza delta. The detailed study of the <span class="hlt">sedimentary</span> architecture and stacking pattern permitted separation of the pile into five depositional units bounded by erosional surfaces and characterised by separate facies associations (genetic sequences = units in this paper). At the base of the series, aeolian deposits (Unit 1) mark the development of a possible coastal desert during the late Miocene aridification. The major Pliocene sea-level rise (Transgressive Systems Tract) led to the drowning of the continental platform into a discrete shoreface-foreshore sequence (Unit 2), followed by an expanded deltaic sequence (Unit 3) that represents the main outcrop of the area. The <span class="hlt">sedimentary</span> fabric of this prograding wedge during the Highstand Systems Tract reveals laterally stacked pluri-hectometic mouth bars built by the abrupt switching of a bird-foot delta during the Pliocene highstand. The clinoforms are deeply incised by submarine gullies filled both by periodic river-driven turbidite and tidal currents (Unit 4) during the coeval growing of the delta. The topset of the prograding wedge and associated gullies infill is truncated by an overall erosional unconformity that marks the widespread development of an extensive braid-delta system (Unit 5) during the lower Pleistocene sea-level drop (Lowstand Systems Tract). The last 6 m of the Braid-delta unit is overprinted by a ferallitic profile, forming the surface of the plateau and indicating long-term subaerial exposure and weathering processes consistent with the maximum warming of the middle to late Pleistocene interglacial periods. The successive abrupt shifts of the depositional systems through the <span class="hlt">sedimentary</span> pile indicate a high-amplitude sea level amplified by major coastal uplifts and the reorganisation of the fluvial network. In this context, the palaeo-Cuanza prograding wedge signals the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUSMGP41A..09E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUSMGP41A..09E"><span>Magnetic susceptibility and cyclostratigraphy of upper Jurassic marly formations (ANDRA, underground research laboratory, Bure, Eastern Paris <span class="hlt">Basin</span>): Record of Milankovitch cycles, <span class="hlt">sedimentary</span> gaps, and implications for regional correlation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Emilia, H.; Bruno, G.; Pierre-Yves, C.; Slah, B.; Pascal, E.; Linda, H.; Christian, R.</p> <p>2006-05-01</p> <p>This study integrates research conducted by ANDRA at the Underground Research Laboratory of Bure (Meuse, France) to investigate the feasibility of a deep geological waste repository in clay for high-level and long-lived intermediate-level radioactive waste. The aim of this study is to detect possible <span class="hlt">sedimentary</span> gaps in the upper Callovian-lower Oxfordian homogeneous marly formation where the laboratory is located, and to estimate the duration of stages and biostratigraphic zonation by comparison with a <span class="hlt">basin</span> sequence from the southeast of France that is presumed to have accumulated continuously. The search for hiatuses was made using a high resolution cyclostratigraphic approach based on the study of magnetic susceptibility (MS) fluctuations. Four ANDRA boreholes (EST 342, EST 322, EST 103 and EST 312) oriented on a SW-NE transect (40 kilometers) were analyzed. Magnetic susceptibility measurements were made on core samples with a Bartington Instruments MS2E1 sensor every 4 centimeters. Sedimentological data suggest that variations of the clay content influence the long term evolution of MS. The high frequency variations in MS were subjected to spectral analysis. Composite cycles of 0.5, 1 and 2.5 m thickness were recognized on the basis of frequency ratio and correspond to the frequency ratio of orbital Milankovitch cycles. The duration of the Mariae ammonite zone in the Paris <span class="hlt">Basin</span> was estimated by counting the cycles, to be between 2.4 and 2.6 My ± 0.3 ky (borehole EST 322 & EST 103). The amplitude spectrum shows (1) sedimentation rate variations in particular in the lower Oxfordian and (2) interruptions in cycle evolution correlated to sequential limits. We interpret these zones as short condensed levels. The same methods were applied to sections from the southeast of France (Aspres-sur-Buëch, Thuoux), and the Mariae ammonite zone estimated to be between 2.3 and 2.8 My of age. By comparison of this biostratigraphic zone between the two studied regions</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5970559','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5970559"><span>Tectono-<span class="hlt">sedimentary</span> evolution of southern part of Benue Trough: from an asymmetric <span class="hlt">basin</span> in middle Albian to an infilled <span class="hlt">basin</span> in mid-Cenomanian</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ojoh, K.A.; Popoff, M.</p> <p>1989-03-01</p> <p>Before the opening of the Equatorial domain of the South Atlantic, the initiation and installation of most intracontinental <span class="hlt">basins</span> within Gondwanaland took place before the Albian in northeastern Brazil and west Africa. The first pronounced marine incursion in the southern part of the Benue Trough was in the middle Albian. Subsidence was localized in the deep asymmetrical middle Albian <span class="hlt">basin</span>. The latter, combined with a lowstand marine ingression in the southern Benue Trough and the progressive rifting-drifting of Africa and South America, engendered an unstable, tectonically active, over-supplied <span class="hlt">basin</span> characterized by megaslumps and turbidites. During the late Albian, differential subsidence installed a stable platform with organic-rich fossiliferous black shales and littoral deposits contemporaneous with a highstand of sea level and the interconnection of the Central and South Atlantic oceans in the proto Gulf of Guinea. Volcanosedimentary tendencies have been documented from the littoral deposits, and pyroclastics containing molluscan fragments in the southern Benue Trough have also been attributed to the upper Albian. The high rate of subsidence during the Albian became very slow in the Cenomanian. It corresponds to a period of eustatic fall of sea level during the early and middle Cenomanian with high clastic influx into the <span class="hlt">basin</span>. The middle Cenomanian is characterized as the period of an infilled <span class="hlt">basin</span> with subaerial-submarine erosional surface (unconformity type 2) in the southern Benue Trough. This may be attributed to the global character of the Cenomanian lowstand of sea level.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20080026258&hterms=aeroespacial&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Daeroespacial','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20080026258&hterms=aeroespacial&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Daeroespacial"><span>The Rio Tinto <span class="hlt">Basin</span>, Spain: Mineralogy, <span class="hlt">Sedimentary</span> Geobiology, and Implications for Interpretation of Outcrop Rocks at Meridiani Planum, Mars</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fernandez-Remolar, David C.; Morris, Richard V.; Gruener, John E.; Amils, Ricardo; Knoll, Andrew H.</p> <p>2005-01-01</p> <p>Exploration by the NASA rover Opportunity has revealed sulfate- and hematite-rich <span class="hlt">sedimentary</span> rocks exposed in craters and other surface features of Meridiani Planum, Mars. Modern, Holocene, and Plio-Pleistocene deposits of the Rio Tinto, southwestern Spain, provide at least a partial environmental analog to Meridiani Planum rocks, facilitating our understanding of Meridiani mineral precipitation and diagenesis, while informing considerations of martian astrobiology. Oxidation, thought to be biologically mediated, of pyritic ore bodies by groundwaters in the source area of the Rio Tinto generates headwaters enriched in sulfuric acid and ferric iron. Seasonal evaporation of river water drives precipitation of hydronium jarosite and schwertmannite, while (Mg,Al,Fe(sup 3+))-copiapite, coquimbite, gypsum, and other sulfate minerals precipitate nearby as efflorescences where locally variable source waters are brought to the surface by capillary action. During the wet season, hydrolysis of sulfate salts results in the precipitation of nanophase goethite. Holocene and Plio-Pleistocene terraces show increasing goethite crystallinity and then replacement of goethite with hematite through time. Hematite in Meridiani spherules also formed during diagenesis, although whether these replaced precursor goethite or precipitated directly from groundwaters is not known. The retention of jarosite and other soluble sulfate salts suggests that water limited the diagenesis of Meridiani rocks. Diverse prokaryotic and eukaryotic microorganisms inhabit acidic and seasonally dry Rio Tinto environments. Organic matter does not persist in Rio Tinto sediments, but biosignatures imparted to <span class="hlt">sedimentary</span> rocks as macroscopic textures of coated microbial streamers, surface blisters formed by biogenic gas, and microfossils preserved as casts and molds in iron oxides help to shape strategies for astrobiological investigation of Meridiani outcrops.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..1211527E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..1211527E"><span>Effects of neotectonic and <span class="hlt">sedimentary</span> processes on the seafloor geomorphology of the Tekirdag <span class="hlt">Basin</span> of the western Marmara Sea (Turkey)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ergin, Mustafa; Yigit-Faridfathi, Füsun</p> <p>2010-05-01</p> <p>This study forms part of a project (TUBITAK YDABCAG 101Y071) with the main purpose of investigation of late Quaternary slope stability, sediment mass movements and turbidite formations in the tectonically active Tekirdag <span class="hlt">Basin</span> and its margins from the western Marmara Sea. The results were also intended to relate to the major earthquakes and sea-level changes. During this project, in 2001 aboard the former R/V MTA Sismik-1, a total of 100 km seismic reflection profiles were obtained along three tracklines representing from shelf to slope to deep <span class="hlt">basin</span> environments. A multichannel airgun seismic system and well-known methods and principles of seismic stratigraphy was used for interpretations. At 11 sites from 29 to 1111 m water depths gravity sediment cores were taken having 100 to 359 cm recoveries and textural and structural characteristics were determined using standard petrographic methods. The NEE-SWW directed seismic profile (TKD-01) which runs parallel to the North Anatolian Fault zone displayed syntectonic sedimentation with negative flower structure that increased in thickness toward the Ganos Fault and pinched out in the east. ENE section of this profile also bears structures of underwater landslides with slump facies. Seismic profile TKD-02 which crosses the Tekirdag <span class="hlt">Basin</span> in WNW-ESE direction most likely displays major 3 fault segments of the NAF zone. Many faults and syntectonic sedimentation structure can be recognized on this profile. A morphological feature of a sediment wedge or former lowstand delta at the present shelf edge can be related to the effects of last sea-level change. Mounded and chaotic seismic reflection configurations which indicate channel and slope-front fill as well as slump facies are thought to reflect submarine slides and slumps. Other morphological features such as incised submarine valleys or channels running E-W direction are also present on this profile. The seismic profile (TKD-03) runs from NNW to SSE across the <span class="hlt">basin</span> and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.6142G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.6142G"><span>Single-well tracer test sensitivity w. r. to hydrofrac and matrix parameters (case study for the Horstberg site in the N-German <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span>)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ghergut, I.; Behrens, H.; Holzbecher, E.; Jung, R.; Sauter, M.; Tischner, T.</p> <p>2012-04-01</p> <p>At the geothermal pilot site Horstberg in the N-German <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span>, a complex field experiment program was conducted (2003-2007) by the Federal Institute for Geosciences and Natural Resources (BGR) together with the Leibniz Institute for Applied Geosciences (GGA), aimed at evaluating the performance of innovative technologies for heat extraction, for direct use, from a single geothermal well[1],[2]. The envisaged single-well operation schemes comprised inter-layer circulation through a <span class="hlt">large</span>-area hydrofrac (whose successful creation could thus be demonstrated), and single-screen 'huff-puff' in suitable (stimulated) layers, seated in sandstone-claystone formations in 3-4 km depth, with temperatures exceeding 160 ° C. Relying on Horstberg tracer-test data, we analyze heat and solute tracer transport in three characteristic hydraulic settings: (A) single-screen, multi-layer push-pull, with spiking and sampling at lower well-screen in low-permeability sandstone layer ('Detfurth'), from which hydrofrac propagation (through several adjacent layers) was initiated; (B) single-screen, single-layer push-pull, with spiking and sampling at upper well-screen within a more permeable sandstone layer ('Solling'); (C) inter-layer vertical push through above-mentioned hydrofrac, with spiking at well-screen of A, and sampling at well-screen of B. Owing to drill-hole deviation, the hydraulically-induced frac will, in its vertical propagation, reach the upper sandstone layer in a certain horizontal distance X from the upper well-screen, whose value turns out to be the major controlling parameter for the system's thermal lifetime under operation scheme C (values of X below ~8 m leading to premature thermal breakthrough, with the minimum-target rate of fluid turnover; however, the injection pressure required for maintaining the target outflow rate will also increase with X, which renders scheme C uneconomical, or technically-infeasible, when X exceeds ~15 m). Tracer signals in C</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.B33D0547M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.B33D0547M"><span>Optimal Use of a dome shaped anticline structure for CO2 storage: A case study for the North German <span class="hlt">sedimentary</span> <span class="hlt">basin</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mitiku, A.; Bauer, S.</p> <p>2012-12-01</p> <p>Structural traps like anticline structures are preferred for carbon dioxide (CO2) sequestration in geological formations, as they limit the lateral spreading of CO2 and thus allow for a localized storage. A typical anticline structure located in the North German <span class="hlt">sedimentary</span> <span class="hlt">basin</span> has been used as a hypothetical but realistic storage site. This study assesses strategies for optimal storage of CO2 in dome shaped anticline structures in terms of well number, well location, well spacing and well alignment. It also analyzes the benefits of different injection strategies. The storage site is situated at a depth of about 3000 m and has an average thickness of 35 m. The model area used in this study is 29 km by 31 km wide and 2304 m thick. The ECLIPSE 300 compositional reservoir simulator with the CO2 STORE option has been used to carry out the numerical simulations. To control CO2 phase movement, the anticline spill point was used as indicator. 4.32 Mt of CO2 per year are injected for 50 years. Scenario simulations were conducted for the injection as well as for the post injection period until the CO2 phase stabilizes. CO2 plume development, pressure build up and the amount of CO2 either in dissolved, residually trapped or mobile form are determined for each scenario. The pressure increase for scenarios with horizontal wells is significantly lower than those with vertical wells, which allows for higher injection rates. However it is observed that the amount of mobile CO2 is slightly higher for horizontal well scenarios, due to the lower contact area between the CO2 phase and the resident brine. If the injection wells are located near the top of the anticline structure, CO2 will spread downward from the injection point and reaches the spill point soon, allowing for small amounts of stored CO2. Therefore the injection wells are positioned along one flank of the anticline structure, which allows a better rise of CO2 into the anticline formation. For equivalent total length</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6601984','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6601984"><span>Tectonic significance of <span class="hlt">large</span>-scale chaotic deposits in a Cretaceous fore-arc <span class="hlt">basin</span>: Valle Formation, Cedros Island (Mexico)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Smith, D.P.; Busby-Spera, C.J. )</p> <p>1990-05-01</p> <p>A mappable, deep-marine slide deposit (olistostrome) within medial-Cretaceous fore-arc <span class="hlt">basin</span> strata (Valle Formation), located on Cedros Island, Baja California Norte, records the initiation of intrabasinal faulting. Studies of both modern and ancient olistostromes show that olistostromes can form in all physiographic provinces (including shelf and abyssal plain) and tectonic settings of the marine environment. A variety of triggering mechanisms have been suggested for olistostromes, including tectonism, sea level changes, diapirism, rapid sedimentation that overloads steep slopes, migration of gas hydrates, or combinations of the above. The olistostrome in the Valle Formation ranges in thickness from 0 to at least 180 m, and extends areally for at least 34 km{sup 2}. It can be divided into two parts. The basal 30-40 m contains <span class="hlt">large</span> (up to 8 m) angular blocks (allolistoliths) derived from the Jurassic substrate. The allolistoliths decrease in abundance upsection, whereas internally coherent intraformational slide blocks (endolistoliths), which reach tens of meters in width, increase. Beds composing the endolistoliths are alternating mudstone and sandstone turbidites that were deposited on a tectonically stable <span class="hlt">basin</span> plain or rise setting before catastrophic failure of the <span class="hlt">sedimentary</span> pile produced the olistostrome. Intrabasinal faulting is invoked as a cause of the sediment failure because of the presence of allolistoliths, which must have been shed into the <span class="hlt">basin</span> from uplifted( ) <span class="hlt">basin</span> floor scarps. Allolistoliths occur sporadically throughout at least 400 m of coarse-clastic sediment gravity-flow deposits that cap the olistostrome, suggesting that intrabasinal faulting continued to affect the <span class="hlt">basin</span> long after the olistrostrome formed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.T51E2954M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.T51E2954M"><span>Tectono-<span class="hlt">sedimentary</span> evolution of the Permian-Triassic extension event in the Zagros <span class="hlt">basin</span> (Iran): results from analogue modelling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Madani-kivi, M.; Zulauf, G.</p> <p>2015-12-01</p> <p>Since the 1970s, the largest oil and gas reservoirs have been discovered in the Permian-Early Triassic formationsin Saudi Arabia. Thus, this time period is important for the discovery of new oil reserves in Iran. The Arabian passivecontinental margin has undergone lithospheric extension during the Permian-Triassic, which led to the formation of theNeo-Tethys. The aim of this paper is to describe the development of the continental rift <span class="hlt">basin</span> in the Zagros region basedon the tectono-sedimentological evolution. We have studied well-log data to specify the distribution of synrift depositsin the Zagros and have related this information to the modelling. Environmental changes indicated by various sedimentarysequences, from a siliciclastic <span class="hlt">basin</span> to a carbonate platform setting, are described. The Cambrian Hormuz salt, whichoverlies the metamorphosed Precambrian basement, becomes effective as a basal detachment layer influencing the styleof overburden deformation during the Permian-Triassic extension event. We have investigated the formation of variousstructures linked to the presence or absence of the Hormuz layer by analogue modelling and relating these structures to theLate Palaeozoic sedimentation. Based on results of the analogue modelling, we argue that the basal detachment layer (Hormuzseries) has contributed to the various structural styles of the extensional <span class="hlt">basin</span> development in the Fars domain and theLorestan domain.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.C43C0562P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.C43C0562P"><span>Marine <span class="hlt">sedimentary</span> provenance evidence for massive discharges of icebergs from the Aurora and Wilkes sub-glacial <span class="hlt">basins</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pierce, E. L.; Williams, T.; van de Flierdt, T.; Hemming, S. R.; Brachfeld, S. A.; Goldstein, S. L.</p> <p>2010-12-01</p> <p>Understanding the evolution of the East Antarctic Ice Sheet (EAIS) is a fundamental goal in the field of paleoclimate today. Given the current and projected state of global warming, it is important to know how an ice sheet that holds over 50 m of sea-level has behaved under warmer conditions in the past. Despite the fact that over 98% of the East Antarctica continent is covered by thick (2.1 km on average) ice, the chronological characterization of glaciogenic detrital hornblende grains has been proven an excellent provenance tool in the investigation of the source areas for ice rafted detritus around Antarctica (Roy et al., 2007, Chem. Geo.). A circum-Antarctica core-top survey of Ar-Ar ages in hornblende grains demonstrates that East Antarctica can be simply divided into several sectors that correspond to modern ice divides and published geochronological evidence from sparse outcrops around the margins of the continent. Williams et al., (2010, EPSL) found evidence in ice rafted detritus layers in ODP Site 1165 from the Wilde drift off Prydz Bay for <span class="hlt">large</span> discharges of icebergs from the Adélie and Wilkes Land coasts occurring during the late Miocene and early Pliocene. Sourcing from the Adélie and Wilkes Land coasts requires iceberg transport more than 1500 km around the Antarctic perimeter, and this is therefore evidence for massive discharges of icebergs from these sectors. In the Aurora and Wilkes <span class="hlt">Basins</span> in these sectors, the ice sheet is grounded well below sea level, and is therefore thought to be potentially unstable under warmer conditions. Such long distant transport of sediments with distinctive sources is reminiscent of Heinrich Events in the North Atlantic. A model often invoked as the cause of these events is the collapse and retreat of ice-streams, which leads to massive discharges of icebergs, laden with sediment, into the ocean. The importance of this interpretation, if true, has led us to make more detailed studies of Quaternary sediments from</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.4118G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.4118G"><span>Investigating traces of early life in the oldest tectono-<span class="hlt">sedimentary</span> <span class="hlt">basin</span> of the 3.5 - 3.1 Ga Barberton greenstone belt, South Africa</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grosch, Eugene</p> <p>2014-05-01</p> <p> temperature and redox conditions surrounding the candidate titanite biotextures. New carbon stable isotope data from pillow cores and rims are presented. U-Pb dating of the alteration in the pillow metabasites determined by laser-ablation ICP-MS, places new constraints on the timing of alteration locally in parts of the pillow lava sequence. A U-Pb detrital zircon provenance study of clastic sediments in the Noisy formation that unconformably overlies the Hooggenoeg pillow lavas, provides evidence for the earliest tectono-<span class="hlt">sedimentary</span> <span class="hlt">basin</span> in the BGB at ca. 3.432 Ga (Grosch et al., 2011). Petrological characterization of altered and deformed mafic-ultramafic rocks of the structurally overlying Kromberg type-section indicates a mid-Archean convergent margin setting at 3.23 Ga, similar to modern-day ophiolite terrains. On the basis of SIMS sulfur isotope data, it is proposed that sulfur-metabolizing bacteria and possibly methanogenic microbes may have thrived in the shallow-marine subsurface of this tectono-<span class="hlt">sedimentary</span> <span class="hlt">basin</span> as early as ca. 3.432 Ga (Grosch & Mcloughlin, 2013). Collectively, the new field mapping and petrological data allows for a better understanding of the early geologic evolution of the Barberton greenstone belt and the potential habitats that may once have been available for early life. The candidate titanite biotextures are thus placed in better metamorphic and geological context. As such their syngenicity and biogenicity are evaluated particularly in light of an early 'bioalteration' subseafloor model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015QSRv..108...76K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015QSRv..108...76K"><span><span class="hlt">Sedimentary</span> response to Milankovitch-type climatic oscillations and formation of sediment undulations: evidence from a shallow-shelf setting at Gela <span class="hlt">Basin</span> on the Sicilian continental margin</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kuhlmann, Jannis; Asioli, Alessandra; Trincardi, Fabio; Klügel, Andreas; Huhn, Katrin</p> <p>2015-01-01</p> <p>A multi-proxy chronological framework along with sequence-stratigraphic interpretations unveils composite Milankovitch cyclicity in the <span class="hlt">sedimentary</span> records of the Last Glacial-Interglacial cycle at NE Gela <span class="hlt">Basin</span> on the Sicilian continental margin. Chronostratigraphic data (including foraminifera-based eco-biostratigraphy and δ18O records, tephrochronological markers and 14C AMS radiometric datings) was derived from the shallow-shelf drill sites GeoB14403 (54.6 m recovery) and GeoB14414 (27.5 m), collected with both gravity and drilled MeBo cores in 193 m and 146 m water depth, respectively. The recovered intervals record Marine Isotope Stages and Substages (MIS) from MIS 5 to MIS 1, thus comprising major stratigraphic parts of the progradational deposits that form the last 100-ka depositional sequence. Calibration of shelf <span class="hlt">sedimentary</span> units with borehole stratigraphies indicates the impact of higher-frequency (20-ka) sea level cycles punctuating this 100-ka cycle. This becomes most evident in the alternation of thick interstadial highstand (HST) wedges and thinner glacial forced-regression (FSST) units mirroring seaward shifts in coastal progradation. Albeit their relatively short-lived depositional phase, these subordinate HST units form the bulk of the 100-ka depositional sequence. Two mechanisms are proposed that likely account for enhanced sediment accumulation ratios (SAR) of up to 200 cm/ka during these intervals: (1) intensified activity of deep and intermediate Levantine Intermediate Water (LIW) associated to the drowning of Mediterranean shelves, and (2) amplified sediment flux along the flooded shelf in response to hyperpycnal plumes that generate through extreme precipitation events during overall arid conditions. Equally, the latter mechanism is thought to be at the origin of undulated features resolved in the acoustic records of MIS 5 Interstadials, which bear a striking resemblance to modern equivalents forming on late-Holocene prodeltas of other</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22506708','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22506708"><span>Major factors affecting in situ biodegradation rates of jet-fuel during <span class="hlt">large</span>-scale biosparging project in <span class="hlt">sedimentary</span> bedrock.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Machackova, Jirina; Wittlingerova, Zdena; Vlk, Kvetoslav; Zima, Jaroslav</p> <p>2012-01-01</p> <p>Biodegradation of petroleum hydrocarbons (TPH), mainly jet fuel, had taken place at the former Soviet Army air base in the Czech Republic. The remediation of <span class="hlt">large</span>-scale petroleum contamination of soil and groundwater has provided valuable information about biosparging efficiency in the sandstone <span class="hlt">sedimentary</span> bedrock. In 1997 petroleum contamination was found to be present in soil and groundwater across an area of 28 hectares, divided for the clean-up purpose into smaller clean-up fields (several hectares). The total estimated quantity of TPH released to the environment was about 7,000 metric tons. Biosparging was applied as an innovative clean-up technology at the site and was operated over a 10-year period (1997-2008). Importance of a variety of factors that affect bacterial activity in unsaturated and saturated zones was widely studied on the site and influence of natural and technological factors on clean-up efficiency in heavily contaminates areas of clean-up fields (initial contaminant mass 111-452 metric ton/ha) was evaluated. Long-term monitoring of the groundwater temperature has shown seasonal rises and falls of temperature which have caused a fluctuation in biodegradation activity during clean-up. By contrast, an overall rise of average groundwater temperature was observed in the clean-up fields, most probably as a result of the biological activity during the clean-up process. The significant rise of biodegradation rates, observed after air sparging intensification, and strong linear correlation between the air injection rates and biodegradation activities have shown that the air injection rate is the principal factor in biodegradation efficiency in heavily contaminated areas. It has a far more important role for achieving a biodegradation activity than the contamination content which appeared to have had only a slight effect after the removal of about 75% of initial contamination.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130013633','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130013633"><span><span class="hlt">Large</span> Impact <span class="hlt">Basins</span> on Mercury: Global Distribution, Characteristics, and Modification History from MESSENGER Orbital Data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fassett, Caleb I.; Head, James W.; Baker, David M. H.; Zuber, Maria T.; Neumann, Gregory A.; Solomon, Sean C.; Klimczak, Christian; Strom, Robert G.; Chapman, Clark R.; Prockter, Louise M.; Phillips, Roger J.; Oberst, Juergen; Preusker, Frank</p> <p>2012-01-01</p> <p>The formation of <span class="hlt">large</span> impact <span class="hlt">basins</span> (diameter D greater than or equal to 300 km) was an important process in the early evolution of Mercury and influenced the planet's topography, stratigraphy, and crustal structure. We catalog and characterize this <span class="hlt">basin</span> population on Mercury from global observations by the MESSENGER spacecraft, and we use the new data to evaluate <span class="hlt">basins</span> suggested on the basis of the Mariner 10 flybys. Forty-two certain or probable impact <span class="hlt">basins</span> are recognized a few additional <span class="hlt">basins</span> that may have been degraded to the point of ambiguity are plausible on the basis of new data but are classified as uncertain. The spatial density of <span class="hlt">large</span> <span class="hlt">basins</span> (D greater than or equal to 500 km) on Mercury is lower than that on the Moon. Morphological characteristics of <span class="hlt">basins</span> on Mercury suggest that on average they are more degraded than lunar <span class="hlt">basins</span>. These observations are consistent with more efficient modification, degradation, and obliteration of the largest <span class="hlt">basins</span> on Mercury than on the Moon. This distinction may be a result of differences in the <span class="hlt">basin</span> formation process (producing fewer rings), greater relaxation of topography after <span class="hlt">basin</span> formation (subduing relief), and/or higher rates of volcanism during the period of heavy bombardment on Mercury compared to the Moon (burying <span class="hlt">basin</span> rings and interiors).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JAESc..73..473K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JAESc..73..473K"><span>Tectonostratigraphy and depositional history of the Neoproterozoic volcano-<span class="hlt">sedimentary</span> sequences in Kid area, southeastern Sinai, Egypt: Implications for intra-arc to foreland <span class="hlt">basin</span> in the northern Arabian-Nubian Shield</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Khalaf, E. A.; Obeid, M. A.</p> <p>2013-09-01</p> <p>This paper presents a stratigraphic and <span class="hlt">sedimentary</span> study of Neoproterozoic successions of the South Sinai, at the northernmost segment of the Arabian-Nubian Shield (ANS), including the Kid complex. This complex is composed predominantly of thick volcano-<span class="hlt">sedimentary</span> successions representing different depositional and tectonic environments, followed by four deformational phases including folding and brittle faults (D1-D4). The whole Kid area is divisible from north to south into the lower, middle, and upper rock sequences. The higher metamorphic grade and extensive deformational styles of the lower sequence distinguishes them from the middle and upper sequences. Principal lithofacies in the lower sequence include thrust-imbricated tectonic slice of metasediments and metavolcanics, whereas the middle and upper sequences are made up of clastic sediments, intermediate-felsic lavas, volcaniclastics, and dike swarms. Two distinct Paleo- depositional environments are observed: deep-marine and alluvial fan regime. The former occurred mainly during the lower sequence, whereas the latter developed during the other two sequences. These alternations of depositional conditions in the volcano-<span class="hlt">sedimentary</span> deposits suggest that the Kid area may have formed under a transitional climate regime fluctuating gradually from warm and dry to warm and humid conditions. Geochemical and petrographical data, in conjunction with field relationships, suggest that the investigated volcano-<span class="hlt">sedimentary</span> rocks were built from detritus derived from a wide range of sources, ranging from Paleoproterozoic to Neoproterozoic continental crust. Deposition within the ancient Kid <span class="hlt">basin</span> reflects a complete <span class="hlt">basin</span> cycle from rifting and passive margin development, to intra-arc and foreland <span class="hlt">basin</span> development and, finally, <span class="hlt">basin</span> closure. The early phase of <span class="hlt">basin</span> evolution is similar to various <span class="hlt">basins</span> in the Taupo volcanics, whereas the later phases are similar to the Cordilleran-type foreland <span class="hlt">basin</span>. The</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997GeCoA..61.2409V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1997GeCoA..61.2409V"><span>A kinetic calculation method of homohopanoid maturation: Applications in the reconstruction of burial histories of <span class="hlt">sedimentary</span> <span class="hlt">basins</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>van Duin, Adri C. T.; Sinninghe Damsté, Jaap S.; Kodpmans, Martin P.; van de Graaf, Bastiaan; de Leeuw, Jan W.</p> <p>1997-06-01</p> <p>Hydrous pyrolysis, performed at relatively low temperatures, of an immature marl yielded artificial maturation data on changes in homohopane isomer compositions. At higher temperatures enhanced amounts of 17α,21β(H)- and 17β,21α-hopanes over 17β,21β(H)-hopanes are observed. The amounts of 22S epimers increase relative to those of their 22R counterparts with increasing temperature. These experimental data, as well as <span class="hlt">sedimentary</span> data on homohopane concentrations, have been reproduced using a kinetic calculation method, based on the thermodynamic stabilities determined by molecular mechanics calculation, using a full isomerization scheme rather than a single direct chiral isomerization step. We need to caution, however, that agreement between the predictions from a theoretical scheme and quantitative measurements is not an unequivocal proof for the chosen kinetic model. Good reproduction of the maturation data was obtained even for those obtained at the highest pyrolysis temperatures, at which significant destruction of hopane isomers was apparent. These results indicate that the kinetic calculation method can be used to model diagenetic and catagenetic reactions affecting biomarker ratios in sediments. Further computer simulations indicate that hopane-hopane interconversion reactions probably only have a minor influence on hopane isomer ratios.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1810990V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1810990V"><span>Hydrogen isotopes on organic compounds express <span class="hlt">large</span> hydrological changes in the Mio-Pliocene of the Dacian <span class="hlt">Basin</span> (Romania)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vasiliev, Iuliana; Reichart, Gert-Jan; Krijgsman, Wout</p> <p>2016-04-01</p> <p>During the late Miocene to Pliocene (˜11 to 3 Ma) <span class="hlt">large</span> part of the southern Eurasian interior was covered by the Eastern Paratethys epicontinental sea. The western most part of the Eastern Paratethys was occupied by the Dacian <span class="hlt">Basin</span>, in the foredeep of the Carpathians. The active subsidence in the front of the Carpathians led to the fast accumulation of up to 10 km think <span class="hlt">sedimentary</span> load in the Dacian <span class="hlt">Basin</span>, all during the latest Miocene and Pliocene. These deposits are now tilted and well exposed along river section in the Carpathian Foredeep. Here we are reconstructing the <span class="hlt">large</span>-scale changes of hydrologic budget in the Dacian <span class="hlt">Basin</span> area over a long time interval (8 to 2.5 Ma). The sampled Rîmnicu S\\varat Valley section covers the Messinian salinity crisis interval, times when the adjacent Mediterranean <span class="hlt">basin</span> suffered severe restrictions of its connections to the Ocean and, subsequently was flooded by the Atlantic at the beginning of Pliocene. We are using compound-specific hydrogen isotopic composition (δD) measured on n-alkanes produced by plant waxes. We focus our analysis on long-chained δDn-alkanes (n-C27 to n-C33) derived from the vascular plant waxes. The saturated hydrocarbon fraction of the extractable organic matter identified in the a-polar fraction of Rîmnicu S\\varat Valley is dominated by a homologous series of n-alkanes ranging from n-C16 to n-C35. The long-chain (>C25), predominantly odd-carbon number homologues are prevailing which is typical for terrestrial higher plant derived n-alkanes, indicating an important terrestrial organic matter input. The ˜ 60 ‰ amplitude of changes for seven consecutive sampled levels measured from both δDn-C17-21 and δDn-C27-31 can be majorly explained by significant changes in the stable hydrogen isotope ratios characterizing the Dacian <span class="hlt">basin</span> waters and the meteoric waters reaching the Dacian <span class="hlt">Basin</span>. This indicates that the hydrological regime in Dacian paleo-<span class="hlt">basin</span> has significantly varied, with heaviest</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.6661S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.6661S"><span><span class="hlt">Large</span>-scale avulsion of the late Quaternary Sutlej river in the NW Indo-Gangetic foreland <span class="hlt">basin</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Singh, Ajit; Gupta, Sanjeev; Sinha, Rajiv; Carter, Andrew; Thomsen, Kristina J.; Mark, Darren F.; Buylaert, Jan-Pieter; Mason, Philippa J.; Murray, Andrew S.; Jain, Mayank; Paul, Debajyoti</p> <p>2015-04-01</p> <p>River avulsions are important processes in the spatial evolution of river systems in tectonically active <span class="hlt">sedimentary</span> <span class="hlt">basins</span> as they govern <span class="hlt">large</span>-scale patterns of sediment routing. However, the pattern and timing of avulsions in <span class="hlt">large</span> river systems are poorly documented and not well understood. Here we document late Quaternary paleo-river channel changes in the Indo-Gangetic <span class="hlt">basin</span> of northwest India. Using a combination of satellite remote sensing and detailed sediment coring, we analyse the <span class="hlt">large</span>-scale planform geometry, and detailed <span class="hlt">sedimentary</span> and stratigraphic nature of a major fluvial <span class="hlt">sedimentary</span> deposit in the shallow subsurface. This sediment body records aggradation of multiple fluvial channel fills. Satellite remote sensing analysis indicates the trace of the buried channel complex and demonstrates that it exists in region of the Himalayan foreland where no major rivers are currently present. Thus it records the former drainage pathway of a major river, which has since been diverted. We use optically stimulated luminescence dating techniques to develop an age model for the stratigraphic succession and hence constrain the timing of river channel existence and diversion. Provenance analysis based on U-Pb dating of detrital zircons and detrital mica Ar-Ar ages indicate sediment sources in the Higher Himalayan Crystalline and Lesser Himalayan Crystalline Series indicating that this paleo-river channel system formed a major perennial river derived from the main body of the Himalaya. Specifically we are able to fingerprint bedrock sources in the catchment of the present-day Sutlej river indicating that the paleo-fluvial system represents the former course of the Sutlej river prior to a major nodal avulsion to its present day course. Our results indicate that on geologically relatively short time-scales, we observe dramatic along strike shifts in the location of major Himalayan rivers. Our sediment records when combined with high-resolution dating and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.H31A0760A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.H31A0760A"><span>Role of the <span class="hlt">sedimentary</span> structure of the urban vadose zone (URVAZO) on the transfer of heavy metals of an urban stormwater <span class="hlt">basin</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Angulo-Jaramillo, R.; Winiarski, T.; Goutaland, D.; Lassabatere, L.</p> <p>2009-12-01</p> <p>Stormwater infiltration <span class="hlt">basins</span> have become a common alternative practice to traditional stormwater pipe networks in urban areas. They are often built in permeable subsurface soils (Urban Vadose Zone, URVAZO), such as alluvial deposits. These <span class="hlt">sedimentary</span> deposits are highly heterogeneous and generate preferential flow paths that may cause either rapid or non-uniform transport of contaminants at great depths. The understanding of how subsurface vadose zone heterogeneities transfer contaminant and fluid flow to the aquifer still remains a challenge in urban hydrology. Indeed, urban stormwater may contain pollutants that can contaminate either soil or groundwater. The aim of this study is to evaluate the role of the lithological heterogeneity of a glaciofluvial deposit underlying an urban infiltration <span class="hlt">basin</span> on the link between water flow and heavy metals retention. A trench wall (14m length x 3m depth) was exposed by excavating the glaciofluvial formation. By a hydrogeophysical approach based on a <span class="hlt">sedimentary</span> structural units and in situ hydraulic characterization (Beerkan tests), a realistic hydrostratigraphic 2D model was defined. The trench was sampled on nine vertical sections of 1.5m length, with ten samples per vertical section following each lithofacies. A total of 90 samples were analyzed. Coarse (mechanical sieving) and fine (laser diffraction) particle size distribution analysis, as well as the concentration of three replicates of Pb, Cu, Zn and organic matter (OM) was measured for each sample. The principal component analysis shows a strong correlation between metal concentration and the lithofacies. This hydrostratigraphic model was implemented in the finite element program Hydrus2D. The soil heterogeneity exerts an impact on the heterogeneity of the water content field under slightly saturated conditions, as they induce capillary barrier effects. These capillary barrier effects may generate water accumulation in some lithofacies overlying matrix</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.3164P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.3164P"><span>Induced seismicity and CO2 leakage through fault zones during <span class="hlt">large</span>-scale underground injection in a multilayered <span class="hlt">sedimentary</span> system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pio Rinaldi, Antonio; Rutqvist, Jonny; Jeanne, Pierre; Cappa, Frederic; Guglielmi, Yves</p> <p>2014-05-01</p> <p>Overpressure caused by the direct injection of CO2 into a deep <span class="hlt">sedimentary</span> system may produce changes in the state of stress, as well as, have an impact on the sealing capabilities of the targeted system. The importance of geomechanics including the potential for reactivating faults associated with <span class="hlt">large</span>-scale geologic carbon sequestration operations has recently become more widely recognized. However, not withstanding the potential for triggering notable (felt) seismic events, the potential for buoyancy-driven CO2 to reach potable groundwater and the ground surface is more important from safety and storage-efficiency perspectives. In this context, this work extends previous studies on the geomechanical modeling of fault responses during underground carbon dioxide injection, focusing on both short- and long-term integrity of the sealing caprock, and hence of potential leakage of either brine or CO2 to shallow groundwater aquifers during active injection. The first part of this work aims to study the fault responses during underground carbon dioxide injection, focusing on the short-term (5 years) integrity of the CO2 repository, and hence on the potential leakage of CO2 to shallow groundwater aquifers. Increased pore pressure can alter the stress distribution on a fault/fracture zone, which may produce changes in the permeability related to the elastic and/or plastic strain (or stress) during single (or multiple) shear ruptures. We account for stress/strain-dependent permeability and study the leakage through the fault zone as its permeability changes along with strain and stress variations. We analyze several scenarios related to the injected amount of CO2 (and hence related to potential overpressure) involving both involving minor and major faults, and analyze the profile risks of leakage for different stress/strain permeability coupling functions, as well as increasing the complexity of the system in terms of hydromechanical heterogeneities. We conclude that</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ExG....47..170L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ExG....47..170L"><span>Helicopter AFMAG (ZTEM) EM and magnetic results over <span class="hlt">sedimentary</span> exhalative (SEDEX) lead-zinc deposits at Howard's Pass in Selwyn <span class="hlt">Basin</span>, Yukon</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Legault, Jean M.; Latrous, Ali; Zhao, Shengkai; Bournas, Nasreddine; Plastow, Geoffrey C.; Xue, Gabriel Guang</p> <p>2016-01-01</p> <p>In 2008, a regional scale 24,675 line-km survey covering a 25,000 km2 area (1 km line spacing) was flown in the Selwyn <span class="hlt">Basin</span>. The survey footprint straddles east-central Yukon and overlaps into the western North-west Territories. In March 2013, Yukon Geological Survey purchased the survey data and, in November 2013, released the data publicly. The Selwyn <span class="hlt">Basin</span> area is prospective for <span class="hlt">sedimentary</span> exhalative (SEDEX)-style Pb-Zn-Ag mineralisation and the z-axis tipper electromagnetic (ZTEM) survey data provide insights into regional structures and plutons in the region. The survey overflew the Howard's Pass SEDEX deposits at the south-eastern edge of the Selwyn <span class="hlt">Basin</span> survey area that hosts a ~250 million tonne resource with ~4.5% Zn and ~1.5% Pb. Airborne geophysics has not been extensively used in SEDEX exploration of the Selwyn <span class="hlt">Basin</span> and the ZTEM survey is one of the few publicly available airborne audio-frequency magnetic (AFMAG) EM-magnetic datasets that offer the opportunity to study the deposit response at Howard's Pass in close detail. Rock physical properties indicate that the lowest resistivities are associated with the Road River Group that contains the Pb-Zn mineralised horizon at Howard's Pass, but also include graphitic shales in the same formation. Major NW-SE to ESE and minor NNW-SSE linear conductive trends correlate with known regional geologic, structural and inferred mineral trends that were previously not visible in magnetic results. At the deposit scale, a thin NW-SE trending conductive lineament extends along the > 37-km-long `Zinc Corridor' horizon at Howard's Pass, but must include both the Pb-Zn sulphide mineralisation deposit horizon as well as the surrounding graphitic black shales. 2D and 3D ZTEM inversions reveal zones of enhanced conductivity along strike and at depth that appear to correlate with the clustering of Pb-Zn deposits, which had not been previously noticed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=PIA05022&hterms=Sedimentary+rocks&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DSedimentary%2Brocks','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=PIA05022&hterms=Sedimentary+rocks&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DSedimentary%2Brocks"><span>Terby <span class="hlt">Sedimentary</span> Rocks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2004-01-01</p> <p><p/> 27 December 2003 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows layered <span class="hlt">sedimentary</span> rock outcrops in Terby Crater, located near 27.7oS, 285.4oW. The layered sediments in Terby are several kilometers thick, attesting to a long history of deposition in this ancient <span class="hlt">basin</span>. The picture covers an area 3 km (1.9 mi) wide. Sunlight illuminates the scene from the upper left.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..1212433H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..1212433H"><span>The Moroccan Turbidite System: a modern example of a multi-<span class="hlt">basin</span> mixed siliciclastic-volcaniclastic deep-water <span class="hlt">sedimentary</span> system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hunt, James; Wynn, Russell; Talling, Peter</p> <p>2010-05-01</p> <p>The Moroccan Turbidite System encompasses three interconnected depocentres: Agadir <span class="hlt">Basin</span>, Seine Abyssal Plain and Madeira Abyssal Plain (Wynn et al. 2002). Both siliciclastic and volcaniclastic turbidites are discovered within these <span class="hlt">basins</span> using piston coring, but have been found to behave differently according to their source and site of entry. The Agadir <span class="hlt">Basin</span> is fed directly by the Agadir Canyon, which is the primary source for siliciclastic shelf-edged derived turbidity currents. The Agadir <span class="hlt">Basin</span> also represents a proximal site of deposition for volcaniclastic turbidites derived directly from Madeira, Tenerife, Las Palma and El Hierro. Though these mixed deposits are also found in the Seine and Madeira Abyssal Plains, the focus of this presentation will be the Agadir <span class="hlt">Basin</span>. Focusing this study is primarily because it removes the added complexity of these flows passing through the regions interconnecting the <span class="hlt">basins</span>, but also because of the higher quality of coring completed in the Agadir <span class="hlt">Basin</span>. Siliciclastic turbidty currents here are affected by both grain-size bypass and flow transformations owing to sensitive interactions with topography (Talling et al. 2007). These deposits form tabular sheets through the centre of the <span class="hlt">basin</span>, with bypass within the Madeira Channel System and recommencing deposition in the distal Madeira Abyssal Plain. Volcaniclastic deposits vary in their behaviour since they travel up-gradient through the Agadir <span class="hlt">Basin</span>, with the deposit architectures not only affected by topographic interactions but with the characteristics of the landslide failures that generated them. <span class="hlt">Large</span> scale volcaniclastic turbidites, such as those from Tenerife and El Hierro, exhibit a vertically stacked sand facies relating to the failure mechanism at source. This facies architecture is maintained >400km away from source in the Agadir <span class="hlt">Basin</span>. In comparison smaller flank failures generate localised turbidite lobes feeding off small aprons, which have been found to be</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GGG....17.1164C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GGG....17.1164C"><span>Stabilization of <span class="hlt">large</span> drainage <span class="hlt">basins</span> over geological time scales: Cenozoic West Africa, hot spot swell growth, and the Niger River</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chardon, Dominique; Grimaud, Jean-Louis; Rouby, Delphine; Beauvais, Anicet; Christophoul, Frédéric</p> <p>2016-03-01</p> <p>Reconstructing the evolving geometry of <span class="hlt">large</span> river catchments over geological time scales is crucial to constraining yields to <span class="hlt">sedimentary</span> <span class="hlt">basins</span>. In the case of Africa, it should further help deciphering the response of <span class="hlt">large</span> cratonic sediment routing systems to Cenozoic growth of the <span class="hlt">basin</span>-and-swell topography of the continent. Mapping of dated and regionally correlated lateritic paleolandscape remnants complemented by onshore sedimentological archives allows the reconstruction of two physiographic configurations of West Africa in the Paleogene. Those reconstructions show that the geometry of the drainage is stabilized by the late early Oligocene (29 Ma) and probably by the end of the Eocene (34 Ma), allowing to effectively link the inland morphoclimatic record to offshore sedimentation since that time, particularly in the case of the Niger catchment—delta system. Mid-Eocene paleogeography reveals the antiquity of the Senegambia catchment back to at least 45 Ma and suggests that a marginal upwarp forming a continental divide preexisted early Oligocene connection of the Niger and Volta catchments to the Equatorial Atlantic Ocean. Such a drainage rearrangement was primarily enhanced by the topographic growth of the Hoggar hot spot swell and caused a stratigraphic turnover along the Equatorial margin of West Africa.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25004850','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25004850"><span>The depositional setting of the Late Quaternary <span class="hlt">sedimentary</span> fill in southern Bannu <span class="hlt">basin</span>, Northwest Himalayan fold and thrust belt, Pakistan.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Farid, Asam; Khalid, Perveiz; Jadoon, Khan Zaib; Jouini, Mohammed Soufiane</p> <p>2014-10-01</p> <p>Geostatistical variogram and inversion techniques combined with modern visualization tools have made it possible to re-model one-dimensional electrical resistivity data into two-dimensional (2D) models of the near subsurface. The resultant models are capable of extending the original interpretation of the data to depict alluvium layers as individual lithological units within the 2D space. By tuning the variogram parameters used in this approach, it is then possible to visualize individual lithofacies and geomorphological features for these lithologic units. The study re-examines an electrical resistivity dataset collected as part of a groundwater study in an area of the Bannu <span class="hlt">basin</span> in Pakistan. Additional lithological logs from boreholes throughout the area have been combined with the existing resistivity data for calibration. Tectonic activity during the Himalayan orogeny uplifted and generated significant faulting in the rocks resulting in the formation of a depression which subsequently has been filled with clay-silt and dirty sand facies typical of lacustrine and flood plain environments. Streams arising from adjacent mountains have reworked these facies which have been eroded and replaced by gravel-sand facies along channels. It is concluded that the sediments have been deposited as prograding fan shaped bodies, flood plain, and lacustrine deposits. Clay-silt facies mark the locations of paleo depressions or lake environments, which have changed position over time due to local tectonic activity and sedimentation. The Lakki plain alluvial system has thus formed as a result of local tectonic activity with fluvial erosion and deposition characterized by coarse sediments with high electrical resistivities near the mountain ranges and fine sediments with medium to low electrical resistivities towards the <span class="hlt">basin</span> center.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMGP13A1279L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMGP13A1279L"><span>Three-dimensional Magnetotelluric Inversion and Model Validation with Potential Field Data and Seismics for the Central Portion of Parana <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span> in Brazil</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>La Terra, E. F.; Fontes, S. L.; Taveira, D. T.; Miquelutti, L. G.</p> <p>2015-12-01</p> <p>The Paraná <span class="hlt">basin</span>, on the central-south region of the South American Plate, is one of the biggest South American intracratonic <span class="hlt">basins</span>. It is composed by Paleozoic and Mesozoic sediments, which were covered by the enormous Cretaceous flood basalts, associated with the rifting of Gondwana and the opening of the South Atlantic Ocean. Its depocenter region, with a maximum estimated depth of just over 7000 m, was crossed by three magnetotelluric - MT profiles proposed by the Brazilian Petroleum Agency (ANP) aimed at better characterizing its geological structure, as the seismic images are very poor. The data include about 350 MT broadband soundings spanning from 1000 Hz down to 2,000 s. The MT data were processed using robust techniques and remote reference. Static shift observed in some stations were corrected based on Transient Electromagnetic - TEM measurements at each site. These models were integrated to existent gravity, magnetic and seismic data for a more comprehensive interpretation of the region. A pilot 3D model has also been constructed on a crustal scale covering the study area using four frequencies per decade in the 3D inversion scheme proposed by Siripunvaraporn et al. (2005). The inversion scheme produced a reliable model and the observations were adequately reproduced, with observed fitting particularly better for the deeper structures related to basement compared to the 2D results. The main features in the conductivity model correspond to known geological features. These included the conductivity structures obtained for the upper crust, i.e. the <span class="hlt">sedimentary</span> sequences, underlain by more resistive material, assumed to be basement. Local resistive features in the near-surface are associated to volcanic basalts covering the sediments. Some highly resistivity horizontal and vertical bodies were associated to volcanic intrusion like dikes and sills. We observed depressions on basement consistent with half-graben structures possibly filled with sandstones.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMOS51D..07L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMOS51D..07L"><span>Comparison between Borehole Geophysical Observations and <span class="hlt">Sedimentary</span> Facies for Three Long Cores Recovered from the Ulleung <span class="hlt">Basin</span>, Korea: Insights into the Distribution of Gas Hydrate</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lim, H.; Lee, S.; Bahk, J.</p> <p>2010-12-01</p> <p>In late 2007, a logging-while-drilling (LWD) operation was performed as part of gas hydrate study at five sites in the Ulleung <span class="hlt">Basin</span>, east of Korea. Of those five sites, long sediment cores were also recovered at three sites (UBGH-4, 9, and 10), allowing us to compare borehole observation results with characteristics of sediment in the cores. In this study, we analyzed the resistivity log and resistivity image recorded using GVR-SONIC-ADN MD200 to see if there exists any meaningful relationship between the borehole data and <span class="hlt">sedimentary</span> facies described in the cores. The presence of fracture zones and their orientation were also estimated from the resistivity images. Site UBGH-4 shows little evidence of disintegrated mud (DITM), an important source of gas hydrate. No notable changes could be seen in the resistivity log or image at this site. On the other hand, at Site UBGH-9, several peaks in resistivity values and numerous fractures are found at 70-150 mbsf. This depth interval matches with DITM found in the cores. At UBGH-10, DITM facies are found below 175 mbsf, but unfortunately due to error in resistivity and image data, it is unclear as to whether this depth coincides with the location of abundant gas hydrate or not. In summary, the argument that massive gas hydrates generally occur in the mud sections with ample fractures could not be thoroughly tested except for Site UBGH-9 where the two features do correlate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017Tectp.698...79C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017Tectp.698...79C"><span>Finite-frequency P-wave tomography of the Western Canada <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span>: Implications for the lithospheric evolution in Western Laurentia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Yunfeng; Gu, Yu Jeffrey; Hung, Shu-Huei</p> <p>2017-02-01</p> <p>The lithosphere beneath the Western Canada <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span> has potentially undergone Precambrian subduction and collisional orogenesis, resulting in a complex network of crustal domains. To improve the understanding of its evolutionary history, we combine data from the USArray and three regional networks to invert for P-wave velocities of the upper mantle using finite-frequency tomography. Our model reveals distinct, vertically continuous high (> 1%) velocity perturbations at depths above 200 km beneath the Precambrian Buffalo Head Terrane, Hearne craton and Medicine Hat Block, which sharply contrasts with those beneath the Canadian Rockies (<- 1%) at comparable depths. The P velocity increases from - 0.5% above 70 km depth to 1.5% at 330 km depth beneath southern Alberta, which provides compelling evidence for a deep, structurally complex Hearne craton. In comparison, the lithosphere is substantially thinner beneath the adjacent Buffalo Head Terrane (160 km) and Medicine Hat Block (200 km). These findings are consistent with earlier theories of tectonic assembly in this region, which featured distinct Archean and Proterozoic plate convergences between the Hearne craton and its neighboring domains. The highly variable, bimodally distributed craton thicknesses may also reflect different lithospheric destruction processes beneath the western margin of Laurentia.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.V13D2643P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.V13D2643P"><span>Geochemistry of Devonian and Carboniferous of <span class="hlt">sedimentary</span> rocks in the Tsetserleg terrane, Hangay-Hentey <span class="hlt">basin</span>, central Mongolia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Purevjav, N.; Roser, B.</p> <p>2011-12-01</p> <p>The Hangay-Hentey <span class="hlt">basin</span> forms part of the Central Asian Orogen Belt in central Mongolia. Contrasting hypotheses have been proposed explain its origin, and its tectonic evolution and provenance are controversial. Many studies to date have been based on geological evidence and only limited petrographic and geochemical analysis is available. The Hangay-Hentey <span class="hlt">basin</span> is divided into seven terranes, of which the Tsetserleg terrane is one. The Tsetserleg terrane consists of siliceous- clastic sediments deposited in a turbidite environment. It is divided into the Middle Devonian Erdenetsogt Formation (sandstone, siltstone, shale and jasper), Middle-Upper Devonian Tsetserleg Formation (sandstone and siltstone), and the Lower Carboniferous Jargalant Formation (finer grained sandstone and mudstone) Sandstone petrography and major and trace element geochemistry of mudstones and sandstones has been used in attempt to constrain some aspects of provenance, tectonic setting and weathering of these Devonian and Carboniferous sediments. The Devonian sandstones are moderately sorted, and composed of sub-angular to sub-rounded quartz, plagioclase, microcline and rock fragments, and a few grains of chlorite and mica. Volcanic (dacite and rhyolite) lithics dominant the lithic population (Lv/L >0.90), and QFL values suggest deposition in an undissected to transitional arc environment. Geochemically the sandstones immature and are classed as wackes, while the mudstones are classed as shales. Major and trace element concentrations of 94 sandstones and mudstones indicate both the Devonian and Carboniferous sediments in the Tsetserleg terrane were mainly derived from felsic sources, although more intermediate detritus dominates in some samples. Major element data suggests deposition probably occurred in an Active Continental Margin setting (ACM), but scatter into the ARC field means an evolved continental island arc (CIA) setting or back arc environment is also possible. Chemical Index of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013CG.....56..131C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013CG.....56..131C"><span>MODTOHAFSD — A GUI based JAVA code for gravity analysis of strike limited <span class="hlt">sedimentary</span> <span class="hlt">basins</span> by means of growing bodies with exponential density contrast-depth variation: A space domain approach</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chakravarthi, V.; Sastry, S. Rajeswara; Ramamma, B.</p> <p>2013-07-01</p> <p>Based on the principles of modeling and inversion, two interpretation methods are developed in the space domain along with a GUI based JAVA code, MODTOHAFSD, to analyze the gravity anomalies of strike limited <span class="hlt">sedimentary</span> <span class="hlt">basins</span> using a prescribed exponential density contrast-depth function. A stack of vertical prisms all having equal widths, but each one possesses its own limited strike length and thickness, describes the structure of a <span class="hlt">sedimentary</span> <span class="hlt">basin</span> above the basement complex. The thicknesses of prisms represent the depths to the basement and are the unknown parameters to be estimated from the observed gravity anomalies. Forward modeling is realized in the space domain using a combination of analytical and numerical approaches. The algorithm estimates the initial depths of a <span class="hlt">sedimentary</span> <span class="hlt">basin</span> and improves them, iteratively, based on the differences between the observed and modeled gravity anomalies within the specified convergence criteria. The present code, works on Model-View-Controller (MVC) pattern, reads the Bouguer gravity anomalies, constructs/modifies regional gravity background in an interactive approach, estimates residual gravity anomalies and performs automatic modeling or inversion based on user specification for basement topography. Besides generating output in both ASCII and graphical forms, the code displays (i) the changes in the depth structure, (ii) nature of fit between the observed and modeled gravity anomalies, (iii) changes in misfit, and (iv) variation of density contrast with iteration in animated forms. The code is used to analyze both synthetic and real field gravity anomalies. The proposed technique yielded information that is consistent with the assumed parameters in case of synthetic structure and with available drilling depths in case of field example. The advantage of the code is that it can be used to analyze the gravity anomalies of <span class="hlt">sedimentary</span> <span class="hlt">basins</span> even when the profile along which the interpretation is intended fails to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3977438','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3977438"><span>Evaluation of Groundwater Recharge Estimates in a Partially Metamorphosed <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span> in a Tropical Environment: Application of Natural Tracers</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Oteng Mensah, Felix; Alo, Clement</p> <p>2014-01-01</p> <p>This study tests the representativeness of groundwater recharge estimates through the chloride mass balance (CMB) method in a tropical environment. The representativeness of recharge estimates using this methodology is tested using evaporation estimates from isotope data, the general spatial distribution of the potential field, and the topographical variations in the area. This study suggests that annual groundwater recharge rates in the area ranges between 0.9% and 21% of annual precipitation. These estimates are consistent with evaporation rates computed from stable isotope data of groundwater and surface water in the Voltaian <span class="hlt">Basin</span>. Moreover, estimates of groundwater recharge through numerical model calibration in other parts of the terrain appear to be consistent with the current data in this study. A spatial distribution of groundwater recharge in the area based on the estimated data takes a pattern akin to the spatial pattern of distribution of the hydraulic head, the local topography, and geology of the terrain. This suggests that the estimates at least qualitatively predicts the local recharge and discharge locations in the terrain. PMID:24772021</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016HydJ...24.1029M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016HydJ...24.1029M"><span>The origin of groundwater arsenic and fluorine in a volcanic <span class="hlt">sedimentary</span> <span class="hlt">basin</span> in central Mexico: a hydrochemistry hypothesis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Morales-Arredondo, Iván; Rodríguez, Ramiro; Armienta, Maria Aurora; Villanueva-Estrada, Ruth Esther</p> <p>2016-06-01</p> <p>A groundwater sampling campaign was carried out in the summer of 2013 in a low-temperature geothermal system located in Juventino Rosas (JR) municipality, Guanajuato State, Mexico. This groundwater presents high concentrations of As and F- and high Rn counts, mainly in wells with relatively higher temperature. The chemistry of major elements was interpreted with different methods, like Piper and D'Amore diagrams. These diagrams allowed for classification of four groundwater types located in three hydrogeological environments. The aquifers are hosted mainly in alluvial-lacustrine sediments and volcanic rocks in interaction with fault and fracture systems. The subsidence, faults and fractures observed in the study area can act as preferential channels for recharge and also for the transport of deep fluids to the surface, especially in the <span class="hlt">basin</span> plain. The formation of a piezometric dome and the observed hydrochemical behavior of groundwater suggest a possible origin of the As and F-. Geochemical processes occurring during water-rock interaction are related to high concentrations of As and F-. High temperatures and alteration processes (like rock weathering) induce dissolution of As and F--bearing minerals, increasing the content of these elements in groundwater.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..1411401C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..1411401C"><span>Pedo-<span class="hlt">sedimentary</span> record of human-environment interaction in ditches and waterlogged depressions on tableland (roman and early medieval period) : micromorphological cases studies from Marne-la-Vallée area (Paris <span class="hlt">Basin</span>, France)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cammas, C.; Blanchard, J.; Broutin, P.; Berga, A.</p> <p>2012-04-01</p> <p>On lœss derived soils located on the Stampien plateau from the Paris <span class="hlt">Basin</span> (France), archaeological anthroposols and ancient cultivated soils are only preserved in very few places. Recent archaeological excavations showed the presence of a pattern of roman ditches and waterlogged depressions (« mares ») under the actual cultivated horizon (Ap). This presence strongly suggests extensive past agricultural practices and water management. An original system of ditches was found Near Marne-la-Vallée (France). It is composed of two parts, one being <span class="hlt">large</span> ditches characterized by flat bottom and sometimes water layered deposits, called « fossés collecteurs » by the archaeologists, and the orher being smaller ditches with colluvial deposits. Our objectives was to use archaeological and micromorphological studies in order to study i) the agricultural function of these ditches and depressions, ii) their evolution with time. Observations conducted on the infilling of a « fossé collecteur » at Bussy-Saint-Georges suggest that it was not part of a drainage system, but that it was a linear water controlled system, with a ramp in one part, and a <span class="hlt">basin</span> or a tank in another, and that it was used for others anthropic activities. In the same area, a <span class="hlt">large</span> waterlogged depression was studied, and micromorphological analysis helped to elucidate its pedo-<span class="hlt">sedimentary</span> formation processes. At the bottom, massive silty clayey matrix retained water. Thin layers composed of silt and clay (indicating low energy flows and decantation), sometimes impregnated and hardened by iron, alternated with silty deposit (indicating higher ernergy water layered deposits). The thin, non porous and iron impregnated crusts helped to raise the depression level, as well as, most likely the water table during roman period, maintaining waterlogging conditions. At the beginning of the early medival period, a slightly peaty event was discriminated. Higher in the profile, in more redoxic conditions</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhDT.......174B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhDT.......174B"><span>Analysis of Quaternary faults and associated deformation of <span class="hlt">sedimentary</span> <span class="hlt">basin</span> fill: Inner continental borderland of southern California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bennett, Jonathan Thomas</p> <p></p> <p>The San Andreas fault system is distributed across strike hundreds of kilometers in southern California. This transform system includes offshore faults along the shelf, slope and adjacent <span class="hlt">basin</span>, comprising part of the Inner California Continental Borderland. Previously, offshore faults have been interpreted as being discontinuous, or certain faults have been interpreted as thrusts between Long Beach and San Diego. Our work, based on ˜3000 kilometers of deep-penetration industry multi-channel seismic reflection data (MCS) as well as high resolution U.S. Geological Survey reflection profiles indicate that many of the offshore faults are more geometrically continuous than previously reported including Newport-Inglewood(NI)-San Mateo-Carlsbad(SMC), and Coronado Bank Detachment(CBD)-Descanso faults. We interpret a ˜18 km wide right step over from the NI-SMC positive flower structure in the north to the CBD-Descanso negative flower structure in the south adjacent to San Diego. These digital fault and stratigraphic interpretations were gridded and depth converted for modeling displacement and its direction on the San Mateo-Carlsbad fault. Stratigraphic interpretations of reflection profiles included the ca. 1.8 Ma top Lower Pico (TLP), which was correlated from wells located offshore Long Beach. Four younger Quaternary unconformities (Q1,Q2,Q3,Q4) are interpreted through much of the study area. We correlate the Q horizons to corehole data in Los Angeles harbor and constrain their ages: Q1 is 160-300; ka Q2 is 300 ka; Q3 300-450 ka; and Q4 ˜600 ka. These ages are several times older than the stratigraphic age model published by Covault and Romans (2009) and an order of magnitude older for the top Lower Pico horizon. Fault slip rates modeled using our new ages would be correspondingly slower than would be the case using the previous ages. We estimate an average right-lateral slip rate of ˜0.44mm/yr since 1.8 Ma on the San Mateo-Carlsbad, which had been published as a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.9825P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.9825P"><span>The Patagonian Orocline: Paleomagnetic evidence of a <span class="hlt">large</span> counter-clockwise rotation during the closure of the Rocas Verdes <span class="hlt">basin</span>.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Poblete, Fernando; Roperch, Pierrick; Herve, Francisco; Ramirez, Cristobal; Arriagada, Cesar</p> <p>2014-05-01</p> <p> (53°-54.5°S), paleomagnetic results indicate a counterclockwise rotation of ~15° after 60 Ma. AMS results show a good correlation between magnetic lineations and the strikes of structures of the fold and thrust belt except near the Magallanes Fagnano fault zone. On the other hand, the magnetic lineations in both intrusive and <span class="hlt">sedimentary</span> rocks along the Beagle Channel are mainly vertical suggesting compressive deformation during pluton emplacement at ~90 Ma along the Beagle channel fault. In summary, the formation of the Patagonian Orocline occurred in two stages during a period of convergence and collision of the Antarctic Peninsula with Patagonia. The first stage is associated with <span class="hlt">large</span> counterclockwise rotations and closure of the Rocas Verdes <span class="hlt">basin</span> during the late Cretaceous. The second stage corresponds to the formation of the curved, mainly non-rotational Magallanes fold and thrust belt during the Tertiary. Funding for this study was provided by CONICYT Project ACT-105 and CONICYT/IRD scholarships to F. Poblete.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.P31E1736M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.P31E1736M"><span>Stress-enhanced magma ascent at the margins of <span class="hlt">large</span> impact <span class="hlt">basins</span> in the solar system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McGovern, P. J.; Powell, K.; Kramer, G. Y.; Litherland, M.</p> <p>2011-12-01</p> <p><span class="hlt">Large</span> impact <span class="hlt">basins</span> are a prime example of an external influence on planetary evolution. However, the resulting <span class="hlt">basin</span> environment can exert strong control on subsequent internal processes of a planet, e.g., volcanism. We argue that the state of lithospheric stress created by initial <span class="hlt">basin</span>-filling magmatism creates favorable environments for magma ascent in annular zones around <span class="hlt">basins</span>. After initial increments of <span class="hlt">basin</span>-filling magmatism, flexural response of the lithosphere creates upper lithosphere compression beneath the load, thereby inhibiting further magma ascent and favoring formation of a complex of horizontally propagating intrusions (sills) that may contribute to observed mascon gravity anomalies [1]. Observed flows from <span class="hlt">basin</span> margins have been attributed to mid-lithosphere outward magma transport to the flexural arch, where extensional upper lithosphere stresses again allow ascent [2]. However, a more direct and powerful ascent mechanism involves a favorable combination of extensional membrane stresses (important for wide loads) and upward-increasing extensional flexural stresses (positive "tectonic stress gradient" [3]) at <span class="hlt">basin</span> margins to drive magma ascent in vertical dikes directly from mantle melt zones to the surface. Moon: The substantial negative buoyancy of dense (Ti-rich) magmas identified in Tranquillitatis and Procellarum mare units could be counteracted by stresses related to Serenitatis and Imbrium loading, respectively. Further, proposed lunar shield volcanoes [4] are all located on the margins of these <span class="hlt">basins</span>, consistent with enhanced magma ascent. Exposures of olivine (as detected by the SELENE Spectral Profiler) in <span class="hlt">basin</span>-ringing zones have been attributed to impact transport of deep crustal or mantle material [5]. However, an examination of higher-resolution spectral data from Chandrayaan-1's M^3 at the Crisium <span class="hlt">basin</span> reveals additional <span class="hlt">basin</span>-rim olivine exposures, including several clearly associated with magmatic transport of olivine as</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.6357L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.6357L"><span>Mapping the geothermal potential of fault zones in the <span class="hlt">sedimentary</span> <span class="hlt">basins</span> of the Belgian and Netherlands border region.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Loveless, Sian; Pluymaekers, Maarten; Lagrou, David; Laenen, Ben; Doornenbal, Hans; De Boever, Eva</p> <p>2014-05-01</p> <p>Faults often determine the success or failure of low enthalpy geothermal projects. This is due to their prevalence throughout the subsurface and capacity to behave as significant fluid flow pathways or baffles (or both simultaneously). Here we present the methodology and results of an assessment of the capacity of faults in the Belgium and Netherlands border region to impact geothermal potential. This work was completed as part of a crossborder project in the European INTERREG Iva program Flanders-The Netherlands. The geothermal potential of reservoirs and fault zones was mapped across the Belgian provinces of Limburg and Antwerpen, and Dutch provinces of Limburg and Noord-Brabant. The Roer Valley Graben (RVG) and the Campine <span class="hlt">Basin</span> are the main structural elements within this region. The four most significant reservoir intervals were correlated across the border. These comprise Upper Cretaceous chalk, Lower Triassic sandstones, Upper Carboniferous sandstones and Lower Carboniferous limestones. Mapped faults cutting these intervals were also correlated. Regional-scale maps have been created indicating the likelihood of fault zones to improve geothermal potential in these intervals. The capacity of faults to improve geothermal potential was determined from factors known to increase or decrease fault permeability. Lithology was a primary consideration: Carbonate rocks tend to fracture along fault zones, creating breccia or joints, resulting in an increased permeability. Permeability can be further increased by karst processes, as evidenced at the Venlo geothermal project, Netherlands. Therefore areas with faults in the carbonate reservoirs were considered to have possible potential. Conversely, permeability is likely to decrease in the clastic reservoir units as cataclastic processes dominate. Such faults were not considered to have additional geothermal potential. The timing of fault activity was considered another key variable. Recently deformed faults are more</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMNH33B..06B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMNH33B..06B"><span>Data Assimilation of InSAR Surface Deformation Measurements for the Estimation of Reservoir Geomechanical Parameters in the Upper Adriatic <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span>, Italy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bau, D. A.; Alzraiee, A.; Ferronato, M.; Gambolati, G.; Teatini, P.</p> <p>2012-12-01</p> <p>In the last decades, extensive work has been conducted to estimate land subsidence due the development of deep gas reservoirs situated in the Upper Adriatic <span class="hlt">sedimentary</span> <span class="hlt">basin</span>, Italy. These modeling efforts have stemmed from the development finite-element (FE) coupled reservoir-geomechanical models that can simulate the deformation due to the change in pore pressure induced by hydrocarbon production from the geological formations. However, the application of these numerical models has often been limited by the uncertainty in the hydrogeological and poro-mechanical input parameters that are necessary to simulate the impact on ground surface levels of past and/or future gas-field development scenarios. Resolving these uncertainties is of paramount importance, particularly the Northern Adriatic region, given the low elevation above the mean sea level observed along most of the coastline and in the areas surrounding the Venice Lagoon. In this work, we present a state-of-the-art data assimilation (DA) framework to incorporate measurements of displacement of the land surface obtained using Satellite Interferometric Synthetic Aperture Radar (InSAR) techniques into the response of geomechanical simulation models. In Northern Italy, InSAR measurement campaigns have been carried out over a depleted gas reservoir, referred to as "Lombardia", located at a depth of about 1200 m in the <span class="hlt">sedimentary</span> <span class="hlt">basin</span> of the Po River plain. In the last years, this reservoir has been used for underground gas storage and recovery (GSR). Because of the pore pressure periodical alternation produced by GSR, reservoir formations have undergone loading/unloading cycles, experiencing effective stress changes that have induced periodical variation of ground surface levels. Over the Lombardia reservoir, the pattern, magnitude and timing of time-laps land displacements both in the vertical and in the East-West directions have been acquired from 2003 until 2008. The availability of these data opens new</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12.6502Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12.6502Q"><span>Biomarker characterization of the record of the OAE1a (early Aptian) in Betic and Cantabrian <span class="hlt">basins</span> (Spain)-<span class="hlt">Sedimentary</span> implications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Quijano, María. Luisa; Castro, José Manuel; Pancost, Richard D.; de Gea, Ginés. A.; Najarro, María.; Aguado, Roque; Rosales, Idoia; Martín-Chivelet, Javier</p> <p>2010-05-01</p> <p>Molecular analyses of <span class="hlt">sedimentary</span> organic matter are powerful tools in assessing the origin of organic matter and its thermal maturity as well as constraining ancient environmental conditions, such as as marine productivity, anoxia in bottom waters or the photic zone and sea surface temperatures. This communication presents the study of four sections recording the OAE1a (early Aptian) in Spain, which are located in two broad <span class="hlt">basins</span> respectively located in the South and the North of Iberia: the Southern Iberian Palaeomargin (Carbonero - CAB, La Frontera - XF and Cau - CAU sections) and the Cantabrian <span class="hlt">Basin</span> (Puente Nansa - PN section). These sections represent depositional settings ranging from platform (CAU, PN) to pelagic environments (CAB, XF). C-isotope profiles and biostratigraphic data are used to define the interval corresponding to the OAE 1a. Here we focus on the biomarker composition of the organic-rich facies, and the integration of these data with the sedimentology, stratigraphy and paleogeography. The study has been based mainly upon the analysis of samples with Gas Chromatography-Mass Spectrometry (GCMS). Four main groups of compounds are present in all sections: n-alkanes, isoprenoids, hopanes and steranes. n-Alkanes and isoprenoids (pristane and phytane) are dominant in most samples. To facilitate interpretation of these distributions, we have calculated the TAR (terrestrial aquatic ratio derived from the ratio of long to short chain compounds) and also the OEP (odd over even predominance of n-alkanes). The ratio of pristane to phytane and various isoprenoid/n-alkanes ratios have also been calculated. The hopanes are represented by a range of C27 to C35 components, with the specific isomers varying amongst the sections due to differences in thermal maturity. Steranes occur as a range of C27, C28 and C29 isomers, whereas diasteranes only occur in the most thermally mature section (CAB). Other compounds of interest include gammacerane and dinosterane</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70019657','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70019657"><span>Spatial analysis of temperature (BHT/DST) data and consequences for heat-flow determination in <span class="hlt">sedimentary</span> <span class="hlt">basins</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Forster, A.; Merriam, D.F.; Davis, J.C.</p> <p>1997-01-01</p> <p><span class="hlt">Large</span> numbers of bottom-hole temperatures (BHTs) and temperatures measured during drill-stem tests (DSTs) are available in areas explored for hydrocarbons, but their usefulness for estimating geothermal gradients and heat-flow density is limited. We investigated a <span class="hlt">large</span> data set of BHT and DST measurements taken in boreholes in the American Midcontinent, a geologically uniform stable cratonic area, and propose an empirical correction for BHTs based on relationships between BHTs, DSTs, and thermal logs. This empirical correction is compared with similar approaches determined for other areas. The data were analyzed by multivariate statistics prior to the BHT correction to identify anomalous measurements and quantify external influences. Spatial patterns in temperature measurements for major stratigraphic units outline relations to regional structure. Comparision of temperature and structure trend-surface residuals reveals a relationship between temperature highs and local structure highs. The anticlines, developed by continuous but intermittent movement of basement fault blocks in the Late Paleozoic, are subtle features having closures of 10-30 m and contain relatively small hydrocarbon reservoirs. The temperature anomalies of the order of 5-7??C may reflect fluids moving upward along fractures and faults, rather than changes in thermal conductivity resulting from different pore fluids.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70033417','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70033417"><span>Spatial analysis of temperature (BHT/DST) data and consequences for heat-flow determination in <span class="hlt">sedimentary</span> <span class="hlt">basins</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Forster, A.; Merriam, D.F.; Davis, J.C.</p> <p>1997-01-01</p> <p><span class="hlt">Large</span> numbers of bottom-hole temperatures (BHTs) and temperatures measured during drill-stem tests (DSTs) are available in areas explored for hydrocarbons, but their usefulness for estimating geothermal gradients and heat-flow density is limited. We investigated a <span class="hlt">large</span> data set of BHT and DST measurements taken in boreholes in the American Midcontinent, a geologically uniform stable cratonic area, and propose an empirical correction for BHTs based on relationships between BHTs, DSTs, and thermal logs. This empirical correction is compared with similar approaches determined for other areas. The data were analyzed by multivariate statistics prior to the BHT correction to identify anomalous measurements and quantify external influences. Spatial patterns in temperature measurements for major stratigraphic units outline relations to regional structure. Comparision of temperature and structure trend-surface residuals reveals a relationship between temperature highs and local structure highs. The anticlines, developed by continuous but intermittent movement of basement fault blocks in the Late Paleozoic, are subtle features having closures of 10-30 m and contain relatively small hydrocarbon reservoirs. The temperature anomalies of the order of 5-7 ??C may reflect fluids moving upward along fractures and faults, rather than changes in thermal conductivity resulting from different pore fluids. ?? Springer-Verlag 1997.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/7036330','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/7036330"><span>Late Pleistocene-Holocene acceleration of uplift rate in southwest Erromango Island, Southern Vanuatu, South Pacific: relation to the growth of the Vanuatuan Mid <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Neef, G.; Hendy, C.</p> <p>1988-07-01</p> <p>Late Quaternary and Holocene raised coral reefs are well developed in southwestern Erromango Island, which lies in the frontal arc area of the Vanuatuan Island Arc. Eight uranium series ages and one /sup 14/C age from samples from coral reefs at three localities range in age from 4800 B.P. to about 320,000 B.P. Six of the samples dated are from the Matiwo Point area. Here the youngest reef has given a /sup 230/Th//sup 234/U age of 4800 B.P. and a slightly older reef, 4.3 m higher in elevation, has a /sup 14/C age of 5270 B.P. Inland of a cliff the youngest three of four northeastward-tilted raised reefs have given /sup 230/Th//sup 234/U ages ranging from 104,000 B.P. to about 320,000 B.P. These data indicate accelerating uplift rates for southwest Erromango: during the periods 320,000-133,000 B.P., 133,000-6000 B.P., and 6000 - 0 B.P. average uplift rates were 0.33 mm/yr, 0.65 mm/yr, and about 1 mm/yr respectively. These data are interpreted to indicate the growth of the Mid <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span>, which lies within the frontal and volcanic arc part of the island arc complex. This increase in uplift/eastward-tilting could represent a Quaternary-Late Pleistocene increase in the subduction rate of the Australian Plate beneath Erromango.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.2918O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.2918O"><span>Intermediate crust (IC); its construction at continent edges, distinctive epeirogenic behaviour and identification as <span class="hlt">sedimentary</span> <span class="hlt">basins</span> within continents: new light on pre-oceanic plate motions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Osmaston, Miles F.</p> <p>2014-05-01</p> <p>Introduction. The plate tectonics paradigm currently posits that the Earth has only two kinds of crust - continental and oceanic - and that the former may be stretched to form <span class="hlt">sedimentary</span> <span class="hlt">basins</span> or the latter may be modified by arc or collision until it looks continental. But global analysis of the dynamics of actual plate motions for the past 150 Ma indicates [1 - 3] that continental tectospheres must be immensely thicker and rheologically stiffer than previously thought; almost certainly too thick to be stretched with the forces available. In the extreme case of cratons, these tectospheric keels evidently extend to 600 km or more [2, 3]. This thick-plate behaviour is attributable, not to cooling but to a petrological 'stiffening' effect, associated with a loss of water-weakening of the mineral crystals, which also applies to the hitherto supposedly mobile LVZ below MORs [4, 5]. The corresponding thick-plate version of the mid-ocean ridge (MOR) process [6 - 8], replacing the divergent mantle flow model, has a deep, narrow wall-accreting axial crack which not only provides the seismic anisotropy beneath the flanks but also brings two outstanding additional benefits:- (i) why, at medium to fast spreading rates, MOR axes become straight and orthogonally segmented [6], (ii) not being driven by body forces, it can achieve the sudden jumps of axis, spreading-rate and direction widely present in the ocean-floor record. Furthermore, as we will illustrate, the crack walls push themselves apart at depth by a thermodynamic mechanism, so the plates are not being pulled apart. So the presence of this process at a continental edge would not imply the application of extensional force to the margin. Intermediate Crust (IC). In seeking to resolve the paradox that superficially extensional structures are often seen at margins we will first consider how this MOR process would be affected by the heavy concurrent sedimentation to be expected when splitting a mature continent. I reason</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1983JGR....88..569Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1983JGR....88..569Y"><span><span class="hlt">Large</span>-scale Quaternary detachments in Ventura <span class="hlt">Basin</span>, southern California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yeats, Robert S.</p> <p>1983-01-01</p> <p>The Ventura <span class="hlt">basin</span> is an east-north-east trending trough in the California Transverse Ranges which records major Quaternary detachment faulting at three levels. The earliest thrusting occurred along weak siltstone interbeds in a sequence dominated by competent <span class="hlt">basin</span>-plain turbidite sandstone. Because sedimentation continued during thrusting, the age, rate, and direction of thrusting can be worked out. Faulting began 1.3 m.y. ago and ceased 0.65 m.y. ago, with a maximum slip rate of 2.8 mm/yr to the southeast. The fault set moved up a 45° ramp and ended as a blind thrust. The ramp had topographic expression on the seafloor, diverting turbidites around the ramp and preserving ash beds along with other hemipelagic sediments on its crest. Following the end of deposition 0.2 m.y. ago, the competent <span class="hlt">basin</span>-plain turbidites underwent flexural slip folding over an incompetent Miocene sequence dominated by shale; underlying competent Paleogene strata were not folded. The south flank of the Ventura Avenue anticline tilted at 3.4 μrad/yr, the anticlinal crest rose at a rate of 15-16 mm/yr decelerating to 4.3-5.2 mm/yr, and the anticline and an adjacent syncline shortened at a rate of 20 mm/yr. The high rate of folding in the Ventura Avenue oil field resulted in overpressured sandstone reservoirs and oil-water interfaces which have not had time to reach gravity equilibrium. The Red Mountain, San Cayetano, and Santa Susana faults mark the surface expression of a seismically active midcrustal detachment which produced convergence across the Ventura <span class="hlt">basin</span> at rates as high as 23 mm/yr. Total convergence across the eastern San Cayetano fault near Fillmore is 11,600±2000 m in the last million years.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.H32D..02S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.H32D..02S"><span>Multicomponent CO2-Brine Simulations of Fluid and Heat Transfer in <span class="hlt">Sedimentary-Basin</span> Geothermal Systems: Expanding Geothermal Energy Opportunities</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Saar, M. O.; Randolph, J. B.</p> <p>2011-12-01</p> <p>In a carbon dioxide plume geothermal (CPG) system, carbon dioxide (CO2) is pumped into existing high-permeability geologic formations that are overlain by a low-permeability caprock. The resulting CO2 plume <span class="hlt">largely</span> displaces native formation fluid and is heated by the natural in-situ heat and background geothermal heat flux. A portion of the heated CO2 is piped to the surface to produce power and/or to provide heat for direct use before being returned to the geologic reservoir. Non-recoverable CO2 in the subsurface is geologically sequestered, serving as a CO2 sink. As such, this approach results in a geothermal power plant with a negative carbon footprint. We present results of calculations concerning geothermal power plant efficiencies and energy production rates in both traditional reservoir-based systems and engineered geothermal systems (EGS) when CO2, rather than water, is used as the subsurface working fluid. While our previous studies have examined geologic systems with established CO2 plumes, we focus here on multicomponent (CO2 + brine) systems. Numerical simulations (e.g., Randolph and Saar, Geophysical Research Letters, 2011) indicate that CPG systems provide several times the heat energy recovery of similar water-based systems. Furthermore, the CPG method results in higher geothermal heat extraction efficiencies than both water- and CO2-based EGS. Therefore, CPG should further extend the applicability of geothermal energy utilization to regions with subsurface temperatures and heat flow rates that are even lower than those that may be added due to switching from water- to CO2-based EGS. Finally, simulations at present suggest that multicomponent effects - e.g., buoyant flow as CO2 rises over denser brine - may enhance heat extraction in CPG systems compared to traditional water-based geothermal approaches.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011SedG..241...40V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011SedG..241...40V"><span>Ichnological trends along an open-water transect across a <span class="hlt">large</span> marginal-marine epicontinental <span class="hlt">basin</span>, the modern Baltic Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Virtasalo, Joonas J.; Bonsdorff, Erik; Moros, Matthias; Kabel, Karoline; Kotilainen, Aarno T.; Ryabchuk, Daria; Kallonen, Aki; Hämäläinen, Keijo</p> <p>2011-11-01</p> <p>Late Holocene sediments in the Baltic Sea provide an opportunity to study lateral changes in the assemblages of identifiable biogenic <span class="hlt">sedimentary</span> structures (ichnofossils) in a <span class="hlt">large</span>, high-latitude semi-enclosed sea with instrumentally determined gradients in biodiversity and environmental factors such as salinity and oxygen availability. Integrated sedimentological and ichnological analysis is carried out on 6 long cores collected along an open-sea, declining salinity transect across the <span class="hlt">basin</span>. Muddy sediments in euhaline (Kattegat) and polyhaline (Mecklenburg Bight) sites are characterized by the archetypal Cruziana Ichnofacies, portrayed by subsurface deposit-feeding structures ( Scolicia and Planolites), surface deposit-feeding structures ( Skolithos), and structures that reflect both these feeding strategies ( Palaeophycus, Arenicolites/ Polykladichnus and unnamed biodeformational structures produced by bivalves). The ichnofossils are tiered to 3 levels. The Cruziana Ichnofacies is impoverished in the higher mesohaline Arkona <span class="hlt">Basin</span> and even more so with declining salinity farther inland. The deepest, oxygen-restricted study sites (Gotland Deep and the western Gulf of Finland) below a permanent halocline are characterized by very small and shallow deposit-feeding structures ( Planolites and rare flat Arenicolites/ Polykladichnus), and poorly developed tiering. The nearly freshwater eastern Gulf of Finland is characterized by the Cenozoic archetypal Mermia Ichnofacies, dominated by narrow and shallow subsurface and surface deposit-feeding structures ( Planolites and flat Arenicolites/ Polykladichnus). <span class="hlt">Large</span> Planolites (3-7 mm in diameter) at this site are untypical of Mermia Ichnofacies assemblages. These results confirm the earlier observations that marine forms dominate brackish-water ichnoassemblages, with the ichnofossil size and diversity decreasing with declining salinity. The results also confirm the predicted decreases in the ichnofossil size and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6815111','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6815111"><span>Buried-euxenic-<span class="hlt">basin</span> model sets Tarim <span class="hlt">basin</span> potential</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hsu, K.J. )</p> <p>1994-11-28</p> <p>The Tarim <span class="hlt">basin</span> is the largest of the three <span class="hlt">large</span> <span class="hlt">sedimentary</span> <span class="hlt">basins</span> 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-<span class="hlt">basin</span> model, should be upper Paleozoic and lower Mesozoic reservoirs trapping oil and gas condensates from lower Paleozoic source beds. The paper describes the <span class="hlt">basin</span> and gives a historical perspective of exploration activities and discoveries. It then explains how this <span class="hlt">basin</span> can be interpreted by the buried-euxenic-<span class="hlt">basin</span> model. The buried-euxenic-<span class="hlt">basin</span> model postulates four stages of geologic evolution: (1) Sinian and early Paleozoic platform sedimentation on relic arcs and deep-marine sedimentation in back-arc <span class="hlt">basins</span> in Xinjiang; (2) Late Paleozoic foreland-<span class="hlt">basin</span> sedimentation in north Tarim; (3) Mesozoic and Paleogene continental deposition, subsidence under <span class="hlt">sedimentary</span> load; and (4) Neogene pull-apart <span class="hlt">basin</span>, wrench faulting and extension.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMPP53A2317S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMPP53A2317S"><span>An Assessment of the Influence of Orbital Forcing on Late Pliocene Global Sea-Level Using a Shallow-Marine <span class="hlt">Sedimentary</span> Record from the Wanganui <span class="hlt">Basin</span>, New Zealand.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sefton, J.; Naish, T.; Mckay, R. M.; Turner, G. M.; Morgans, H. E. G.; Seward, D.; Alloway, B.</p> <p>2015-12-01</p> <p>Classical Milankovitch Theory suggests variance in the orbital cycles of precession (21 kyr) and obliquity (41 kyr) should have a profound influence on insolation and ice volume. However, the globally-integrated ice volume proxy record (benthic δ18O) during the Late Pliocene (3.0-2.6 Ma) is dominated by obliquity-paced cycles, and lacks a significant precession component. A number of hypotheses have been proposed to explain this phenomenon, but paleoclimate records independent of the benthic δ18O record are required to test these. The Wanganui <span class="hlt">Basin</span>, New Zealand, contains a shallow-marine Neogene <span class="hlt">sedimentary</span> succession that is widely recognised as an important site for examining sea-level/ice volume changes at orbital frequencies. Here, we present a record of paleobathymetric changes at an orbital resolution from the Late Pliocene Mangaweka Mudstone outcrop succession. Modern analogue-calibrated water-depth proxies of grainsize and benthic foraminifera census data were used to evaluate paleobathymetric changes. An integrated magneto-, bio- and tephrostratigraphy was developed that constrains the outcrop succession to between ~3.0 Ma and 2.58 Ma. Nine distinct cycles spanning ~400,000 years are identified in the grainsize and benthic foraminifera assemblages. Within the uncertainty of the age model, the Mangaweka Mudstone grainsize cycles can be matched one-for-one to the δ18O cycles, as they display a similar pattern of frequency and amplitude. The frequency of these cycles (and the corresponding interval in the δ18O record) are dominated by the 41 kyr year obliquity cycle, but with a subordinate eccentricity component. Therefore, the fluctuations in the grainsize and benthic foraminifera proxies likely represent an indirect response to global sea-level fluctuations via their effect on continental shelf sediment transport mechanisms. The implications for the orbital theory of the ice ages are that during the Late Pliocene, global ice volume changes responded</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.T11A2872G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.T11A2872G"><span>From Isostasy to Proterozoic Underplating: New Inferences from Crustal Thickness and Vp/Vs Ratio beneath the Western Canada <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gu, Y. J.; Chen, Y.</p> <p>2015-12-01</p> <p>The rapid expansion of regional broadband seismic arrays in Alberta provides an unprecedented opportunity to map the subsurface seismic structure. In this study, we compute the P-to-S receiver functions from 5 regional seismic networks and 62 stations to determine the crustal properties beneath southern-central Alberta, a boundary zone between the Mesozoic Canadian Cordillera and the Precambrian craton(s). The optimal Moho depth and Vp/Vs ratio at each receiver are determined by tracing the direct P, converted (Pms) and reverberated (PpPms and PpSms+PsPms) phases through a three-dimensional shear velocity model. The resulting Moho depth-Vp/Vs ratio (H-K) image shows more coherent stacking amplitudes than the traditional H-K method. The map of Moho depth shows an increase of crustal thickness from an average of 41 km in Precambrian domains to ~50 km beneath the foothills of the Rocky Mountains, which indicates a strong crustal gradient across the craton-domain boundary in the Western Canada <span class="hlt">Sedimentary</span> <span class="hlt">Basin</span> (WCSB). The surface elevations along the foreland belt of the Rockies are isostatically compensated by a thickened crustal root, which is consistent with thick-skinned deformation likely sustained during the Laramide phase of the Farallon subduction. To the west of the foreland belt, however, a relatively thin crust with an average thickness of ~36 km is mapped beneath the extreme topography of southern Canadian Rockies. The lack of a deep crustal root is inconsistent with the Airy isostasy model, implying very high temperatures beneath the Cordillera upper mantle. Ratios of average crustal velocities (Vp/Vs) vary from 1.61 to 1.91 across the study region. The smallest values are observed near the northern Snowbird Tectonic Zone (STZ) and Taltson magmatic arc, which suggest a felsic crust resulted from crustal thickening and melting during the early Proterozoic. On the other hand, the Vp/Vs ratio shows the highest value (~1.9) in the vicinity of the Vulcan</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=PIA03090&hterms=Sedimentary+rocks&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DSedimentary%2Brocks','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=PIA03090&hterms=Sedimentary+rocks&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DSedimentary%2Brocks"><span><span class="hlt">Sedimentary</span> Rocks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2005-01-01</p> <p><p/> 6 November 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows outcrops of <span class="hlt">sedimentary</span> rocks in a crater located just north of the Sinus Meridiani region. Perhaps the crater was once the site of a martian lake. <p/> <i>Location near</i>: 2.9oN, 359.0oW <i>Image width</i>: width: 3 km (1.9 mi) <i>Illumination from</i>: lower left <i>Season</i>: Northern Autumn</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=PIA04592&hterms=Sedimentary+rocks&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DSedimentary%2Brocks','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=PIA04592&hterms=Sedimentary+rocks&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DSedimentary%2Brocks"><span>Schiaparelli <span class="hlt">Sedimentary</span> Rocks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2003-01-01</p> <p>MGS MOC Release No. MOC2-403, 26 June 2003<p/>Some of the most important high resolution imaging results of the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) experiment center on discoveries about the presence and nature of the <span class="hlt">sedimentary</span> rock record on Mars. This old meteor impact crater in northwestern Schiaparelli <span class="hlt">Basin</span> exhibits a spectacular view of layered, <span class="hlt">sedimentary</span> rock. The 2.3 kilometer (1.4 miles) wide crater may have once been completely filled with sediment; the material was later eroded to its present form. Dozens of layers of similar thickness and physical properties are now expressed in a wedding cake-like stack in the middle of the crater. Sunlight illuminating the scene from the left shows that the circle, or mesa top, at the middle of the crater stands higher than the other stair-stepped layers. The uniform physical properties and bedding of these layers might indicate that they were originally deposited in a lake (it is possible that the crater was at the bottom of a much larger lake, filling Schiaparelli <span class="hlt">Basin</span>); alternatively, the layers were deposited by settling out of the atmosphere in a dry environment. This picture was acquired on June 3, 2003, and is located near 0.9oS, 346.2oW.<p/></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.5123H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.5123H"><span>A <span class="hlt">large</span> channel system in the western the Riiser Larsen Sea, East Antarctica: Paleoceanographic and <span class="hlt">sedimentary</span> aspects</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hass, H. Christian; Klages, Johann P.; Kuhn, Gerhard; Forwick, Matthias</p> <p>2016-04-01</p> <p>We investigated seafloor morphology and <span class="hlt">sedimentary</span> processes at the continental margin in the western Riiser Larsen Sea, Antarctica, to reconstruct processes of channel/levee development, and to evaluate the influence of climate through the past 5 marine isotope stages on these processes. Shallow seismic (parametric subbottom profiler) investigations reveal that channels and associated levees form the principal morphological structures in the western Riiser Larsen Sea. The channels are up to several kilometers wide and hundreds of meters deep. They stretch from the upper continental slope towards the Enderby Abyssal Plain. Sediment cores (taken from levee tops) reveal increased amounts of sand and coarser silt during warmer climate phases (MIS 1, 3, 5). The sand is mainly composed of planktic foraminifers and IRD, both suggesting seasonally open waters (interglacials). The carbonate-free sortable silt mean grain size suggests increased bottom current speed during the warmer climate phases. We postulate, that the occurrence of coastal polynyas and strong sea-ice formation through katabatic winds promote the formation of cold waters and brines. These are channeled on the continental slope and intensify turbidity currents that occur on the steep slopes. Alternatively, the newly formed dense waters can be taken up by westward flowing contour currents and thus support the formation of turbidity currents. It is suggested that either process supports downslope sediment transport and levee growth during warm climate phases. Under cold climates a permanent ice cover is suggested at least for the positions of the sediment cores (seasonally open waters today). These reveal significantly IRD and carbonate-depleted sediments during the cold climate phases. Hence, polynyas may have formed further to the north over deeper waters. The volume of the cooled-down waters and brines was likely smaller and probably not able to reach the sea floor due to mixing with upwelling warmer</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1815555S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1815555S"><span>Bridging the gap between small and <span class="hlt">large</span> scale sediment budgets? - A scaling challenge in the Upper Rhone <span class="hlt">Basin</span>, Switzerland</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schoch, Anna; Blöthe, Jan; Hoffmann, Thomas; Schrott, Lothar</p> <p>2016-04-01</p> <p>A <span class="hlt">large</span> number of sediment budgets have been compiled on different temporal and spatial scales in alpine regions. Detailed sediment budgets based on the quantification of a number of sediment storages (e.g. talus cones, moraine deposits) exist only for a few small scale drainage <span class="hlt">basins</span> (up to 10² km²). In contrast, <span class="hlt">large</span> scale sediment budgets (> 10³ km²) consider only long term sediment sinks such as valley fills and lakes. Until now, these studies often neglect small scale sediment storages in the headwaters. However, the significance of these sediment storages have been reported. A quantitative verification whether headwaters function as sediment source regions is lacking. Despite substantial transport energy in mountain environments due to steep gradients and high relief, sediment flux in <span class="hlt">large</span> river systems is frequently disconnected from alpine headwaters. This leads to significant storage of coarse-grained sediment along the flow path from rockwall source regions to <span class="hlt">large</span> <span class="hlt">sedimentary</span> sinks in major alpine valleys. To improve the knowledge on sediment budgets in <span class="hlt">large</span> scale alpine catchments and to bridge the gap between small and <span class="hlt">large</span> scale sediment budgets, we apply a multi-method approach comprising investigations on different spatial scales in the Upper Rhone <span class="hlt">Basin</span> (URB). The URB is the largest inneralpine <span class="hlt">basin</span> in the European Alps with a size of > 5400 km². It is a closed system with Lake Geneva acting as an ultimate sediment sink for suspended and clastic sediment. We examine the spatial pattern and volumes of sediment storages as well as the morphometry on the local and catchment-wide scale. We mapped sediment storages and bedrock in five sub-regions of the study area (Goms, Lötschen valley, Val d'Illiez, Vallée de la Liène, Turtmann valley) in the field and from high-resolution remote sensing imagery to investigate the spatial distribution of different sediment storage types (e.g. talus deposits, debris flow cones, alluvial fans). These sub</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70034382','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70034382"><span>Controls on <span class="hlt">large</span> landslide distribution and implications for the geomorphic evolution of the southern interior Columbia River <span class="hlt">basin</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Safran, E.B.; Anderson, S.W.; Mills-Novoa, M.; House, P.K.; Ely, L.</p> <p>2011-01-01</p> <p><span class="hlt">Large</span> landslides (>0.1 km2) are important agents of geomorphic change. While most common in rugged mountain ranges, <span class="hlt">large</span> landslides can also be widespread in relatively low-relief (several 100 m) terrain, where their distribution has been relatively little studied. A fuller understanding of the role of <span class="hlt">large</span> landslides in landscape evolution requires addressing this gap, since the distribution of <span class="hlt">large</span> landslides may affect broad regions through interactions with channel processes, and since the dominant controls on landslide distribution might be expected to vary with tectonic setting. We documented >400 landslides between 0.1 and ~40 km2 across ~140,000 km2 of eastern Oregon, in the semiarid, southern interior Columbia River <span class="hlt">basin</span>. The mapped landslides cluster in a NW-SE-trending band that is 50-100 km wide. Landslides predominantly occur where even modest local relief (~100 m) exists near key contacts between weak <span class="hlt">sedimentary</span> or volcaniclastic rock and coherent cap rock. Fault density exerts no control on landslide distribution, while ~10% of mapped landslides cluster within 3-10 km of mapped fold axes. Landslide occurrence is curtailed to the NE by thick packages of coherent basalt and to the SW by limited local relief. Our results suggest that future mass movements will localize in areas stratigraphically preconditioned for landsliding by a geologic history of fluviolacustrine and volcaniclastic sedimentation and episodic capping by coherent lava flows. In such areas, episodic landsliding may persist for hundreds of thousands of years or more, producing valley wall slopes of ~7??-13?? and impacting local channels with an evolving array of mass movement styles. ?? 2011 Geological Society of America.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009ESF....16..288W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009ESF....16..288W"><span>Description of Cretaceous <span class="hlt">Sedimentary</span> Sequence of the Second and Third Member of the Qingshankou Formation Recovered by CCSD-SK-Is Borehole in Songliao <span class="hlt">Basin</span>: Lithostratigraphy, <span class="hlt">Sedimentary</span> Facies and Cyclic Stratigraphy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Pujun; Gao, Youfeng; Cheng, Rihui; Wang, Guodong; Wu, Heyong; Wan, Xiaoqiao; Yang, Gansheng; Wang, Zhongxing</p> <p></p> <p>The second and third member of the Qingshankou Formation recovered by CCSD-SK-Is borehole (China Cretaceous Continental Scientific Drilling-SongkeI-the south borehole) is 415.61 m long and 100% of cores recovery. The age of the member corresponds approximately to the Coniacian. The sequence and process of lithology-lithofacies and cyclic stratigraphy were revealed by a detailed core description. 12 rock types and 2 kinds of <span class="hlt">sedimentary</span> subfacies including semi-deep lake and shallow lake were recognized from the drilling core of the second and third member of the Qingshankou Formation. 10 <span class="hlt">sedimentary</span> microfacies are present, including dolomite, marl, limestone, oil shale, semi-deep lake turbidite, volcanic ash, seismite, semi-deep lake mudstone, shallow lake mudstone, and shallow lake turbidite microfacies. The second and third member of the Qingshankou Formation represents 422 meter-scale cycles (sixth-order cycle), 130 fifth-order cycles, 21 fourth-order cycles, and one third-order cycles. The special lithologies, such as mudstone, seismite, dolomite, volcanic ash, and so on are important to researches on source rocks and lacustrine event sediments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70028055','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70028055"><span>Gas-water-rock interactions in Frio Formation following CO2 injection: Implications for the storage of greenhouse gases in <span class="hlt">sedimentary</span> <span class="hlt">basins</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Kharaka, Yousif K.; Cole, David R.; Hovorka, Susan D.; Gunter, W.D.; Knauss, Kevin G.; Freifeild, Barry M.</p> <p>2006-01-01</p> <p>To investigate the potential for the geologic storage of CO2 in saline <span class="hlt">sedimentary</span> aquifers, 1600 t of CO2 were injected at 1500 m depth into a 24-m-thick sandstone section of the Frio Formation, a regional brine and oil reservoir in the U.S. Gulf Coast. Fluid samples obtained from the injection and observation wells before CO2 injection showed a Na-Ca-Cl–type brine with 93,000 mg/L total dissolved solids (TDS) at near saturation with CH4 at reservoir conditions. Following CO2 breakthrough, samples showed sharp drops in pH (6.5–5.7), pronounced increases in alkalinity (100–3000 mg/L as HCO3) and Fe (30–1100 mg/L), and significant shifts in the isotopic compositions of H2O, dissolved inorganic carbon (DIC), and CH4. Geochemical modeling indicates that brine pH would have dropped lower but for the buffering by dissolution of carbonate and iron oxyhydroxides. This rapid dissolution of carbonate and other minerals could ultimately create pathways in the rock seals or well cements for CO2 and brine leakage. Dissolution of minerals, especially iron oxyhydroxides, could mobilize toxic trace metals and, where residual oil or suitable organics are present, the injected CO2 could also mobilize toxic organic compounds. Environmental impacts could be major if <span class="hlt">large</span> brine volumes with mobilized toxic metals and organics migrated into potable groundwater. The δ18O values for brine and CO2 samples indicate that supercritical CO2 comprises ∼50% of pore-fluid volume ∼6 mo after the end of injection. Postinjection sampling, coupled with geochemical modeling, indicates that the brine gradually will return to its preinjection composition.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JSAES..64...94R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JSAES..64...94R"><span>Multi-method provenance model for early Paleozoic <span class="hlt">sedimentary</span> <span class="hlt">basins</span> of southern Peru and northern Bolivia (13°-18°S)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Reimann Zumsprekel, Cornelia R.; Bahlburg, Heinrich; Carlotto, Victor; Boekhout, Flora; Berndt, Jasper; Lopez, Shirley</p> <p>2015-12-01</p> <p>In early Paleozoic time the Peru-Bolivia Trough at the South American Gondwana margin accommodated <span class="hlt">large</span> volumes of siliciclastic detritus of hitherto <span class="hlt">largely</span> unknown provenance. A multi-method provenance study of framework components, heavy minerals and whole rock geochemistry of Ordovician to Devonian formations of southern Peru and northern Bolivia reveals the predominant contribution from upper crustal sources. Main heavy minerals include zircon, tourmaline, rutile, apatite, garnet, epidote, monazite, and titanite and are strongly biased diagenetically towards the stable phases. Electron microprobe single grain analysis of tourmaline and rutile indicate that detrital tourmalines were derived mainly from metasedimentary, and subordinately, from granitic sources. Cr/Nb ratios in rutiles point to a metamafic derivation for 20-40% of grains, the remainder originating in felsic lithologies. Zr in rutile thermometry indicates a provenance from relatively high-grade metamorphic rocks transformed at temperatures between 500 °C and 900 °C, with clusters at c. 600 °C, 700 °C and 800 °C. U-Pb geochronological analysis of rutiles was <span class="hlt">largely</span> unsuccessful due to high concentrations of common Pb. Three ages could be obtained and fall between 525 and 545 Ma, probably linking this detritus to the hidden Neoproterozoic orogen in what are now Cordillera Oriental and Sierras Subandinas. The most notable feature of the whole rock geochemical data is a high Cr content in the majority of samples, which otherwise have a composition similar to weathered upper continental crust. The elevated Cr contents indicates that ophiolitic rocks were either exposed to erosion abundantly in the source areas or had previously supplied significant volumes of detritus to intermittent sediment storage systems now eroded into the studied <span class="hlt">sedimentary</span> rocks. Potential source candidates include the Ordovician metamorphic Tapo Ultramafic Complex in the Cordillera Oriental of central Peru, and the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S43B2786P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S43B2786P"><span>An Integrated Approach for the <span class="hlt">Large</span>-Scale Simulation of <span class="hlt">Sedimentary</span> <span class="hlt">Basins</span> to Study Seismic Wave Amplification</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Poursartip, B.</p> <p>2015-12-01</p> <p>Seismic hazard assessment to predict the behavior of infrastructures subjected to earthquake relies on ground motion numerical simulation because the analytical solution of seismic waves is limited to only a few simple geometries. Recent advances in numerical methods and computer architectures make it ever more practical to reliably and quickly obtain the near-surface response to seismic events. The key motivation stems from the need to access the performance of sensitive components of the civil infrastructure (nuclear power plants, bridges, lifelines, etc), when subjected to realistic scenarios of seismic events. We discuss an integrated approach that deploys best-practice tools for simulating seismic events in arbitrarily heterogeneous formations, while also accounting for topography. Specifically, we describe an explicit forward wave solver based on a hybrid formulation that couples a single-field formulation for the computational domain with an unsplit mixed-field formulation for Perfectly-Matched-Layers (PMLs and/or M-PMLs) used to limit the computational domain. Due to the material heterogeneity and the contrasting discretization needs it imposes, an adaptive time solver is adopted. We use a Runge-Kutta-Fehlberg time-marching scheme that adjusts optimally the time step such that the local truncation error rests below a predefined tolerance. We use spectral elements for spatial discretization, and the Domain Reduction Method in accordance with double couple method to allow for the efficient prescription of the input seismic motion. Of particular interest to this development is the study of the effects idealized topographic features have on the surface motion when compared against motion results that are based on a flat-surface assumption. We discuss the components of the integrated approach we followed, and report the results of parametric studies in two and three dimensions, for various idealized topographic features, which show motion amplification that depends, as expected, on the relation between the topographic feature's characteristics and the dominant wavelength. Lastly, we report results involving three-dimensional simulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010E%26PSL.297...57L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010E%26PSL.297...57L"><span>Application of the authigenic 10Be/ 9Be dating method to continental sediments: Reconstruction of the Mio-Pleistocene <span class="hlt">sedimentary</span> sequence in the early hominid fossiliferous areas of the northern Chad <span class="hlt">Basin</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lebatard, Anne-Elisabeth; Bourlès, Didier L.; Braucher, Régis; Arnold, Maurice; Duringer, Philippe; Jolivet, Marc; Moussa, Abderamane; Deschamps, Pierre; Roquin, Claude; Carcaillet, Julien; Schuster, Mathieu; Lihoreau, Fabrice; Likius, Andossa; Mackaye, Hassan Taisso; Vignaud, Patrick; Brunet, Michel</p> <p>2010-08-01</p> <p>The concentrations of atmospheric cosmogenic 10Be normalized to the solubilized fraction of its stable isotope 9Be have been measured in the authigenic phase leached from silicated continental sediments deposited since the upper Miocene in the northern Chad <span class="hlt">Basin</span>. This method is validated by the systematic congruence with the biochronological estimations based on the fossil mammal evolutive degree of faunal assemblages. The fifty-five authigenic 10Be/ 9Be ages obtained along 12 logs distributed along two West-East cross sections that encompass best representative Mio-Pliocene outcrops including paleontological sites show a systematic stratigraphic decrease when considering all studied <span class="hlt">sedimentary</span> facies extending from the Pleistocene up to 8 Ma and allow performing geologic correlations otherwise impossible in the studied area. The resulting global sequence evidences and temporally specifies the succession of the main paleoenvironments that have developed in this region since the Miocene. Under the special conditions encountered in the northern Chad <span class="hlt">Basin</span>, this study demonstrates that the authigenic 10Be/ 9Be ratio may be used as a dating tool of continental <span class="hlt">sedimentary</span> deposits from 1 to 8 Ma. The half-life of 10Be theoretically allowing dating up to 14 Ma, it may have fundamental implications on important field research such as paleoclimatology and, through the dating of fossiliferous deposits in paleontology and paleoanthropology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015IJEaS.104..123L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015IJEaS.104..123L"><span>The volcano-<span class="hlt">sedimentary</span> evolution of a post-Variscan intramontane <span class="hlt">basin</span> in the Swiss Alps (Glarus Verrucano) as revealed by zircon U-Pb age dating and Hf isotope geochemistry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Letsch, Dominik; Winkler, Wilfried; von Quadt, Albrecht; Gallhofer, Daniela</p> <p>2015-01-01</p> <p>The Late Palaeozoic Glarus Verrucano <span class="hlt">basin</span> (GVB, Glarus Alps, eastern Switzerland) formed as an intramontane graben in the aftermath of the Variscan orogeny. Its fill, the Glarus Verrucano, consists of immature alluvial fan and playa lake deposits with intercalated bimodal volcanics (basalts and rhyolites). Despite its importance for local and regional geology, no modern sedimentologic or stratigraphic studies on the GVB exist. By means of sedimentologic and geochronologic studies, we reconstruct the volcano-<span class="hlt">sedimentary</span> evolution of the GVB: it developed at the Carboniferous/Permian boundary and experienced a first (bimodal) volcanic phase around 285 Ma. For the same time, indications for temporarily humid climate in the otherwise rather arid Early Permian are demonstrated (e.g. pyrite-bearing sandstones). During the Middle and Early Late Permian, increasing aridity is indicated by playa deposits, fanglomerates and subaerial ignimbrites, which mark a second (silicic) volcanic phase at 268 Ma. The detrital zircon age spectra are dominated by Late Variscan ages and thus demonstrate that older <span class="hlt">sedimentary</span> and metamorphic rocks once forming the Variscan nappe edifice were already mostly eroded at that time. Finally, some larger-scale speculations are given which could indicate a causal connection between the widespread tectono-magmatic Mid-Permian Episode and the local development of the Glarus Verrucano <span class="hlt">basin</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMPP41B1357A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMPP41B1357A"><span>Changes in Holocene Climate, Fire and Vegetation from the Northeastern Great <span class="hlt">Basin</span>: A 13,500 Year <span class="hlt">Sedimentary</span> Record from Swan Lake, ID.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Anderson, L.; Wahl, D.; Miller, D. M.; Rosario, J. J.; Presnetsova, L.</p> <p>2014-12-01</p> <p>Precipitation patterns in the western US are characterized by a north-south dipole, typically manifesting as wet conditions in the northwest and a dry southwest. This pattern is, in <span class="hlt">large</span> part, determined by the strength and position of the Pacific subtropical jet, which is responsible for the generation and trajectory of winter storms that provide the majority of annual moisture. Modern climate variability on interannual/decadal timescales results in latitudinal shifts in the boundary between the wet-north/dry-south; strong ENSO activity typically results in drying in the north and increased precipitation in the south. Previous paleoclimate work in the Great <span class="hlt">Basin</span> has shown coherence in the timing of major climatic shifts in the Holocene, yet past spatial variability of the dipole remains little studied. Here we present new data from a site that lies within the transition zone of the precipitation dipole. Swan Lake, located in southeastern Idaho along the northeast edge of the Great <span class="hlt">Basin</span>, was formed in the spillway channel created by the catastrophic flooding of Lake Bonneville ~14,500 yrs BP. This study seeks to provide insight into the timing and magnitude of late-glacial and Holocene climate variability in the northeastern Great <span class="hlt">Basin</span> in order to better understand past spatial variability of precipitation patterns. Charcoal, pollen and sedimentological data from a 7.65 m sediment core from Swan Lake are used to reconstruct fire history and vegetation change in the area. Age control is provided by 15 AMS radiocarbon determinations. Results are placed in the context of regional paleoclimate studies. These data build on earlier work by Bright (1966) who reported on pollen, macrofossils and sedimentology from Swan Lake, as well as characterizing the modern vegetation biomes within this area and the climate conditions necessary for their occurrence. Our preliminary data suggest dramatic reduction in fire frequency coinciding with results from nearby studies that</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4682852','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4682852"><span>1.8 Billion Years of Detrital Zircon Recycling Calibrates a Refractory Part of Earth’s <span class="hlt">Sedimentary</span> Cycle</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hadlari, Thomas; Swindles, Graeme T.; Galloway, Jennifer M.; Bell, Kimberley M.; Sulphur, Kyle C.; Heaman, Larry M.; Beranek, Luke P.; Fallas, Karen M.</p> <p>2015-01-01</p> <p>Detrital zircon studies are providing new insights on the evolution of <span class="hlt">sedimentary</span> <span class="hlt">basins</span> but the role of <span class="hlt">sedimentary</span> recycling remains <span class="hlt">largely</span> undefined. In a broad region of northwestern North America, this contribution traces the pathway of detrital zircon sand grains from Proterozoic sandstones through Phanerozoic strata and argues for multi-stage <span class="hlt">sedimentary</span> recycling over more than a billion years. As a test of our hypothesis, integrated palynology and detrital zircon provenance provides clear evidence for erosion of Carboniferous strata in the northern Cordillera as a sediment source for Upper Cretaceous strata. Our results help to calibrate Earth's <span class="hlt">sedimentary</span> cycle by showing that recycling dominates <span class="hlt">sedimentary</span> provenance for the refractory mineral zircon. PMID:26658165</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6649837','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6649837"><span><span class="hlt">Large</span>-scale diabase intrusion in the Durham Triassic <span class="hlt">Basin</span> of North Carolina: geophysics and geochemistry</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bolich, R.E.; Bevis, M.G.; Won, I.J.; Fodor, R.V.</p> <p>1985-01-01</p> <p>Gravity and magnetic data obtained from the Durham Triassic <span class="hlt">Basin</span> of North Carolina reveal pronounced positive gravity and magnetic anomalies of 10 milligals and 300 gammas, respectively, along the western border of the <span class="hlt">basin</span>. In the vicinity of these anomalies, diabase outcrops, some with chilled margins and others with flow features, occur sporadically, but have a combined area of about 100 sq. km. Two-dimensional modeling of the gravity data indicates that the diabase body accounts for the gravity anomaly as a semi-continuous subsurface intrusion. The intrusive body is greater than 250 m thick near the western border of the <span class="hlt">basin</span>, but thins to about 100 m near the center of the <span class="hlt">basin</span>. Geochemical data for samples recovered from 4 air-drill sites at one diabase outcrop in Butner, North Carolina yield high MgO concentrations, and low FeO, K2O, and TiO2. The geophysical and geochemical data are consistent with an uncontaminated basaltic magma ascending along a major fissure or fissures and into the <span class="hlt">basin</span>. In the <span class="hlt">basin</span>, the diabase encountered unlithified sediments, resulting in both intrusive and extrusive forms. Although similar chemical compositions for Mesozoic North American dikes have been reported, this is the first indication of an intrusive body of such a <span class="hlt">large</span> extent and primitive chemical composition.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24243265','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24243265"><span>Spatial variability of sediment ecotoxicity in a <span class="hlt">large</span> storm water detention <span class="hlt">basin</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Merchan, Carolina Gonzalez; Perrodin, Yves; Barraud, Sylvie; Sébastian, Christel; Becouze-Lareure, Céline; Bazin, Christine; Kouyi, Gislain Lipeme</p> <p>2014-04-01</p> <p>Detention <span class="hlt">basins</span> are valuable facilities for urban storm water management, from both the standpoint of flood control and the trapping of pollutants. Studies performed on storm water have shown that suspended solids often constitute the main vector of pollutants (heavy metals, polycyclic aromatic hydrocarbon (PAH), etc.). In order to characterise the ecotoxicity of urban sediments from storm water detention <span class="hlt">basins</span>, the sediments accumulated over a 6-year period were sampled at five different points through the surface of a <span class="hlt">large</span> detention <span class="hlt">basin</span> localised in the east of Lyon, France. A specific ecotoxicological test battery was implemented on the solid phase (raw sediment) and the liquid phase (interstitial water of sediments). The results of the study validated the method formulated for the ecotoxicological characterization of urban sediments. They show that the ecotoxicological effect of the sediments over the <span class="hlt">basin</span> is heterogeneous and greater in areas often flooded. They also show the relationship between, on one hand, the physical and chemical characteristics of the sediments and, on the other hand, their ecotoxicity. Lastly, they contribute to a better understanding of the dynamics of the pollution close to the bottom of detention <span class="hlt">basins</span>, which can be useful for improving their design. The results of this research raise particularly the issue of using oil separators on the surface of detention <span class="hlt">basins</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016OcDyn..66..549C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016OcDyn..66..549C"><span>Response of <span class="hlt">large</span>-scale coastal <span class="hlt">basins</span> to wind forcing: influence of topography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Wen L.; Roos, Pieter C.; Schuttelaars, Henk M.; Kumar, Mohit; Zitman, Tjerk J.; M. H. Hulscher, Suzanne J.</p> <p>2016-04-01</p> <p>Because wind is one of the main forcings in storm surge, we present an idealised process-based model to study the influence of topographic variations on the frequency response of <span class="hlt">large</span>-scale coastal <span class="hlt">basins</span> subject to time-periodic wind forcing. Coastal <span class="hlt">basins</span> are represented by a semi-enclosed rectangular inner region forced by wind. It is connected to an outer region (represented as an infinitely long channel) without wind forcing, which allows waves to freely propagate outward. The model solves the three-dimensional linearised shallow water equations on the f plane, forced by a spatially uniform wind field that has an arbitrary angle with respect to the along-<span class="hlt">basin</span> direction. Turbulence is represented using a spatially uniform vertical eddy viscosity, combined with a partial slip condition at the bed. The surface elevation amplitudes, and hence the vertical profiles of the velocity, are obtained using the finite element method (FEM), extended to account for the connection to the outer region. The results are then evaluated in terms of the elevation amplitude averaged over the <span class="hlt">basin</span>'s landward end, as a function of the wind forcing frequency. In general, the results point out that adding topographic elements in the inner region (such as a topographic step, a linearly sloping bed or a parabolic cross-<span class="hlt">basin</span> profile), causes the resonance peaks to shift in the frequency domain, through their effect on local wave speed. The Coriolis effect causes the resonance peaks associated with cross-<span class="hlt">basin</span> modes (which without rotation only appear in the response to cross-<span class="hlt">basin</span> wind) to emerge also in the response to along-<span class="hlt">basin</span> wind and vice versa.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19890008964','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19890008964"><span>Martian sediments and <span class="hlt">sedimentary</span> rocks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Markun, C. D.</p> <p>1988-01-01</p> <p>Martian sediments and <span class="hlt">sedimentary</span> rocks, clastic and nonclastic, should represent a high priority target in any future return-sample mission. The discovery of such materials and their subsequent analysis in terrestrial laboratories, would greatly increase the understanding of the Martian paleoclimate. The formation of Martian clastic <span class="hlt">sedimentary</span> rocks, under either present, low-pressure, xeric conditions or a postulated, high-pressure, hydric environment, depends upon the existence of a supply of particles, various cementing agents and depositional <span class="hlt">basins</span>. A very high resolution (mm-cm range) photographic reconnaissance of these areas would produce a quantum jump in the understanding of Martian geological history. Sampling would be confined to more horizontal (recent) surfaces. Exploration techniques are suggested for various hypothetical Martian <span class="hlt">sedimentary</span> rocks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002Geomo..42..117L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002Geomo..42..117L"><span>The Barranco de Tirajana <span class="hlt">basin</span>, Gran Canaria (Spain). A major erosive landform caused by <span class="hlt">large</span> landslides</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lomoschitz, Alejandro; Meco, Joaquín.; Corominas, Jordi</p> <p>2002-01-01</p> <p>The Barranco de Tirajana (BdT), located on the island of Gran Canaria (Spain), has some specific features that differentiate it from the ravines of other volcanic islands in the Atlantic Ocean. The origin of this unusually wide upper <span class="hlt">basin</span> (35 km 2) has been under discussion over the last century although its erosional origin is nowadays widely accepted. The purpose of this paper is to describe the landslide deposits that appear at the bottom of the <span class="hlt">basin</span> and to assess their role in the geomorphological evolution of the <span class="hlt">basin</span>. We suggest that the BdT <span class="hlt">basin</span> is a major erosional landform initiated by important ravine incision and widened by a <span class="hlt">large</span> number of landslides. There are 28 <span class="hlt">large</span> landslides within the BdT <span class="hlt">basin</span>. The main movements were of rock-slide and debris-slide types, affecting 70% and 25% of the total area, respectively. In addition, modes of displacement were predominantly translational (rock-, debris-, and earth-slides) consisting of 89% of the total, compared to rotations and flows that constitute only 11%. Three main periods of landslide activity have been established in the development of the BdT <span class="hlt">basin</span>, using geomorphological criteria. Period I includes ancient movements that could have started at about 0.6 Ma or even 2.7 Ma ago and are considered as abandoned landslides. Period II corresponds to old landslides considered as dormant, which occurred within the Middle-Upper Pleistocene. Finally, period III includes recent Upper Pleistocene landslides and Holocene landslides that are still active. We suggest that interglacials in the Canary Islands and NW Africa included humid and wet episodes that could account for the occurrence of periods of landslide activity in the BdT <span class="hlt">basin</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ThApC.tmp..205Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ThApC.tmp..205Z"><span>The influence of <span class="hlt">large</span>-scale climate phenomena on precipitation in the Ordos <span class="hlt">Basin</span>, China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhong, Yu; Lei, Liyuan; Liu, Youcun; Hao, Yonghong; Zou, Chris; Zhan, Hongbin</p> <p>2016-09-01</p> <p><span class="hlt">Large</span>-scale atmospheric circulations significantly affect regional precipitation patterns. However, it is not well known whether and how these phenomena affect regional precipitation distribution in northern China. This paper reported the individual and coupled effects of El Niño-Southern Oscillation (ENSO), Indian summer monsoon (ISM), Pacific Decadal Oscillation (PDO), and Atlantic Multidecadal Oscillation (AMO) on annual precipitation for the Ordos <span class="hlt">Basin</span>, an arid and semi-arid <span class="hlt">basin</span>, currently with major industries of coal, fossil oil, natural gas, and halite in north central China. Our results showed that ENSO and ISM exerted substantial impact on annual precipitation while the impact of PDO and AMO was relatively limited. There were 24 and 15 out of 33 stations showing significant differences (p < 0.1) in annual precipitation (from 1950 to 2013) for ENSO and ISM, respectively. The median precipitation across the <span class="hlt">basin</span> during El Niño years was 21.49 % higher than that during La Niña years and 17.28 % higher during the positive phase of ISM years compared to the negative phase of the ISM years. The impacts of ENSO and ISM on precipitation were enhanced during a PDO cold phase but weakened in a PDO warm phase. The impact of ENSO was still enhanced by an AMO warm phase. The effects of climatic phenomena on precipitation showed a strong spatial difference in the Ordos <span class="hlt">Basin</span>. The impact of ENSO was mostly evident around the edges of the <span class="hlt">basin</span> while the impact of ISM decreases from south to north. The deserts (i.e., Hobq Desert and Mu Us Sandy Land) in the center of the <span class="hlt">basin</span> were less affected by these <span class="hlt">large</span>-scale climatic phenomena. An improved understanding of such relationships would be helpful in water resource planning and disaster management for the Ordos <span class="hlt">Basin</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMGP51A1311H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMGP51A1311H"><span>Origin of Strong Lunar Magnetic Anomalies: More Detailed Mapping in Regions Antipodal to Young <span class="hlt">Large</span> <span class="hlt">Basins</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hood, L. L.; Richmond, N.; Spudis, P.</p> <p>2012-12-01</p> <p>Previous work has found evidence that the largest concentrations of strong lunar crustal magnetic fields are in regions antipodal to four young <span class="hlt">large</span> lunar <span class="hlt">basins</span>: Orientale, Imbrium, Crisium, and Serenitatis (Mitchell et al., Icarus, 2008; and references therein). A preliminary model for the production of lunar <span class="hlt">basin</span> antipodal magnetic signatures has been developed (Hood and Artemieva, Icarus, 2008; Gattacceca et al., EPSL, 2010). The model involves shock magnetization of crustal materials in the presence of a transient magnetic field amplified by the expanding ionized vapor-melt cloud as it converges in the antipodal region. The model does not exclude a core dynamo; any ambient magnetic field (external solar wind or internal core dynamo) can be amplified in the antipodal zone. In this paper, we report further efforts to map in more detail Lunar Prospector magnetometer data in regions antipodal to young lunar <span class="hlt">basins</span>. In addition to the four <span class="hlt">basins</span> identified above, we also consider the polar Schrodinger <span class="hlt">basin</span>, which is one of the three youngest lunar <span class="hlt">basins</span> and which has not been previously considered in this context. We apply a direct mapping method (see Hood, Icarus, 2011 for details) to produce more complete maps of lunar magnetic anomalies at low altitudes over the central far side and over the north polar region. We also consider geologic data and spacecraft imagery to identify unusual modified terrain, which may be indicative of shock modification in the same <span class="hlt">basin</span> antipodal zones. Previous work indicates the existence of such terrain antipodal to Imbrium, Orientale, and Serenitatis, as well as antipodal to the Caloris <span class="hlt">basin</span> on Mercury. Results first confirm the concentrations of anomalies antipodal to Orientale, Imbrium, Crisium, and Orientale, and the occurrence of modified terrain in three of the four <span class="hlt">basin</span> antipode zones (see, e.g., Richmond et al., JGR, 2005). In addition, we report here evidence for a <span class="hlt">large</span> concentration of anomalies that is centered</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.3335B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.3335B"><span>Vegetation recovery assessment following <span class="hlt">large</span> wildfires in the Mediterranean <span class="hlt">Basin</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bastos, A.; Gouveia, C. M.; Trigo, R. M.; DaCamara, C. C.</p> <p>2012-04-01</p> <p>Mediterranean ecosystems have evolved along with fire, adapting to quick recovering following wildfire events. However, vegetation species respond differently to the changes in fire regimes that have been observed in the past decades in the Mediterranean. These changes, which occurred mainly due to socio-economic and climatic changes, led to dramatic modifications of landscape composition and structure (Malkinson et al., 2011). Post-fire vegetation recovery depends on environmental factors such as landscape features and climatic variables and on specific plant traits; however it also depends on the differentiated response of each species to the characteristics of fire regimes, such as recurrence, severity and extent. The complexity of the interactions between these factors emphasizes the importance of assessing quantitatively post-fire recovery as well as the role of driving factors of regeneration over different regions in the Mediterranean. In 2006, Spain experienced the fire season with larger fires, restricted to a relatively small region of the province of Galicia, that represents more than 60% of total burned area of this fire season (92000ha out of 148827 ha). The 2007 fire season in Greece was remarkably severe, registering the highest value of burnt area (225734 ha) since 1980. Finally, in 2010 a very <span class="hlt">large</span> wildfire of about 5000 ha occurred in Mount Carmel, Israel, with major social and environmental impacts. The work relies on monthly NDVI data from SPOT/VEGETATION at 1km spatial resolution over the period from September 1998 - August 2011 for Spain, Greece and Israel. Here we have applied the same sequential methodology developed at our laboratory, starting by the identification of very <span class="hlt">large</span> burnt scars by means of a spatial cluster analysis followed by the application of the monoparametric model (Gouveia et al., 2010; Bastos et al., 2011) in order to study post-fire vegetation dynamics. Post-fire recovery times were estimated for burnt scars from each</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JAfES..99..307K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JAfES..99..307K"><span>Physical volcanology, geochemistry and <span class="hlt">basin</span> evolution of the Ediacaran volcano-<span class="hlt">sedimentary</span> succession in the Bas Draâ inlier (Ouarzazate Supergroup, Western Anti-Atlas, Morocco)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Karaoui, Brahim; Breitkreuz, Christoph; Mahmoudi, Abdelkader; Youbi, Nasrrddine</p> <p>2014-11-01</p> <p>New geologic mapping, lithofacies and granulometric analysis, and geochemistry from the volcano-<span class="hlt">sedimentary</span> successions of the central part of the Bas Draâ inlier, Western Anti-Atlas, constrain the Ediacaran Ouarzazate Supergroup evolution during the post-collisional stage of the Pan-African orogeny. Volcanosedimentary facies analysis is the key aspect of the present contribution. We distinguished sixteen terrestrial volcanosedimentary lithofacies in the Bas Draâ succession (BDS), which reaches a total thickness of 2000 m. BDS evolution can be grouped into four units (Aouinet Aït Oussa I to IV, AO I-AO IV). The earliest volcanic activity produced rhyolitic ignimbrite sheets (AO I), which had been considered as lava flows by previous workers, and which were presumably related to caldera system(s). During AO II, a complex of high-silica andesitic and rhyolitic lavas formed, punctuated by the explosive eruption of a high-temperature silica-rich magma leading to the formation of parataxitic ignimbrite. AO III consists of basalt and andesite lava fields and small explosive, in parts phreatomagmatic volcanic vents. It is dissected by fluvial systems depositing external non-volcanic and local volcanic debris. BDS evolution terminated with the formation of a <span class="hlt">large</span> SiO2-rich lava dome complex (AO IV), accompanied by small basalt effusive event. Volcanosedimentary facies analysis infers that the BDS evolved in a continental extensional setting developing in a low topography under humid paleoclimatic conditions. Alteration textures are dominated by a piemontite-calcite-albite-quartz (+ iron oxides) assemblage. Chemical analysis of BDS volcanic and subvolcanic rocks belongs to high-k calc-alkaline and alkali-calcic to alkaline magmatic trend typical for a post-collision setting. Trace elements spidergrams show a pattern typical for subduction-related suites of orogenic belts. REE patterns show moderate enrichment in LREE relative to flat HREE, with strong negative Eu</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5865273','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5865273"><span>Parana <span class="hlt">basin</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>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.</p> <p>1987-05-01</p> <p>The Parana <span class="hlt">basin</span> is a <span class="hlt">large</span> intracratonic <span class="hlt">basin</span> in South America, developed entirely on continental crust and filled with <span class="hlt">sedimentary</span> 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 <span class="hlt">basin</span>. Five major depositional sequences (Silurian, Devonian, Permo-Carboniferous, Triassic, Juro-Cretaceous) constitute the stratigraphic framework of the <span class="hlt">basin</span>. 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 <span class="hlt">basin</span> 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 <span class="hlt">basin</span> 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 <span class="hlt">basin</span>. 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).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JSAES..66...15F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JSAES..66...15F"><span>Palynological and <span class="hlt">sedimentary</span> analysis of the Igarapé Ipiranga and Querru 1 outcrops of the Itapecuru Formation (Lower Cretaceous, Parnaíba <span class="hlt">Basin</span>), Brazil</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ferreira, Neila N.; Ferreira, Elizabete P.; Ramos, Renato R. C.; Carvalho, Ismar S.</p> <p>2016-03-01</p> <p>The siliciclastic sediments of the Itapecuru Formation occur in a <span class="hlt">large</span> area of the Parnaíba <span class="hlt">Basin</span> and its deposits crop out along the Itapecuru River, in Maranhão State, northern Brazil. The palynological analysis of the Igarapé Ipiranga and Querru 1 outcrops strata yields a rich and diversified data. The presence of index-palynofloras in assemblages allows the identification of the Complicatisaccus cearensis Zone, of Late Aptian-Early Albian age. Terrestrial palynomorphs are abundant in the assemblages, being represented by bryophytes and pteridophytes, especially perisporate trilete spores (Crybelosporites and Perotrilites), and gymnosperms and angiosperms (Afropollis and Elaterosporites). The composition of palynological assemblages suggests the presence of moist soils for both outcrops. Acritarchs were recovered in the Querru 1 outcrop, which suggest a marine setting supporting a tidal flat environment indicated by facies associations. Furthermore, reworked Paleozoic palynomorphs were observed in the Querru 1 outcrop. The microflora from Igarapé Ipiranga outcrop suggests terrestrial environment corroborating with floodplain environment indicated by facies association.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=PIA07840&hterms=Sedimentary+rocks&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DSedimentary%2Brocks','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=PIA07840&hterms=Sedimentary+rocks&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DSedimentary%2Brocks"><span>Gale <span class="hlt">Sedimentary</span> Rocks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2005-01-01</p> <p><p/> 15 April 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows outcroppings of layered, <span class="hlt">sedimentary</span> rock in eastern Gale Crater. North-central Gale Crater is the site of a mound that is more than several kilometers thick and <span class="hlt">largely</span> composed of <span class="hlt">sedimentary</span> rocks that record a complex history of deposition and erosion. At one time, Gale Crater might have been completely filled and buried beneath the martian surface. <p/> <i>Location near</i>: 4.9oS, 221.6oW <i>Image width</i>: 3 km (1.9 mi) <i>Illumination from</i>: upper left <i>Season</i>: Southern Winter</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20817368','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20817368"><span>Depositional history of <span class="hlt">sedimentary</span> linear alkylbenzenes (LABs) in a <span class="hlt">large</span> South American industrial coastal area (Santos Estuary, Southeastern Brazil).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Martins, César C; Bícego, Márcia C; Mahiques, Michel M; Figueira, Rubens C L; Tessler, Moyses G; Montone, Rosalinda C</p> <p>2010-11-01</p> <p>This paper reports the reconstruction of the contamination history of a <span class="hlt">large</span> South American industrial coastal area (Santos Estuary, Brazil) using linear alkylbenzenes (LABs). Three sediment cores were dated by (137)Cs. Concentrations in surficial layers were comparable to the midrange concentrations reported for coastal sediments worldwide. LAB concentrations increased towards the surface, indicating increased waste discharges into the estuary in recent decades. The highest concentration values occurred in the early 1970s, a time of intense industrial activity and marked population growth. The decreased LAB concentration, in the late 1970s was assumed to be the result of the world oil crisis. Treatment of industrial effluents, which began in 1984, was represented by decreased LAB levels. Microbial degradation of LABs may be more intense in the industrial area sediments. The results show that industrial and domestic waste discharges are a historical problem in the area.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/127315','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/127315"><span>Pricaspian depression - the unique oil & gas-bearing <span class="hlt">basin</span> of the World</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Abdulin, A.A.; Daukeev, S.Z.; Votsalevsky, E.S.</p> <p>1995-08-01</p> <p>The Pricaspian depression is a unique oil and gas-bearing <span class="hlt">basin</span>. The total <span class="hlt">sedimentary</span> rock volume in the <span class="hlt">basin</span> is about 8 million km{sup 3}. More than 100 oil and gas fields have been discovered in the <span class="hlt">basin</span> including extremely <span class="hlt">large</span> fields, such as Tengiz, Astrakhan, and Karachaganak. The <span class="hlt">basin</span> is filled with Devonian to Neogene sediments, a very wide range in age for a single <span class="hlt">sedimentary</span> <span class="hlt">basin</span>. The range in age and composition of the rocks results in complex geology, complex conditions for producing oil and gas, and complex phase states of the hydrocarbons present. The <span class="hlt">basin</span> fill comprises the Paleozoic section below the Kungurian salt, the Kungurian and Kungurian to Permian salt-bearing section, and the upper Permian to Paleogene and Neogene <span class="hlt">sedimentary</span> complexes above the salt. The thick <span class="hlt">sedimentary</span> succession and specific oil and gas productivity are what make the Pricaspian <span class="hlt">basin</span> a unique <span class="hlt">sedimentary</span> <span class="hlt">basin</span>. The geologic structure and <span class="hlt">basin</span> evolution during the Paleozoic, details of sedimentation in the Devonian to Early Permian, initial salt deposition and the dynamic evolution of salt domes, hydrocarbon generation and accumulation zones, various trap types, field types, hydrodynamic regimes, and hydrochemical content of groundwater are discussed in the paper.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12.3090L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12.3090L"><span>Application of the authigenic 10Be/9Be dating method to continental sediments: reconstruction of the Mio-Pleistocene <span class="hlt">sedimentary</span> sequence in the early hominid fossiliferous areas of the northern Chad <span class="hlt">Basin</span>.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lebatard, Anne-Elisabeth; Bourlès, Didier L.; Arnold, Maurice; Duringer, Philippe; Schuster, Mathieu; Jolivet, Marc; Braucher, Régis; Taisso Mackaye, Hassan; Vignaud, Patrick; Brunet, Michel</p> <p>2010-05-01</p> <p>Concentrations of atmospheric cosmogenic nuclide 10Be measured using accelerator mass spectrometry (AMS) were normalized to the solubilised fraction of its stable isotope 9Be in the authigenic component leached from continental deposits in order to date siliceous sediments deposited since the upper Miocene in the Djurab Desert in the northern Chad <span class="hlt">Basin</span>. The demonstrated systematic strong agreement between the biochronological estimations and the calculated authigenic 10Be/9Be ages strongly suggests not only that the initial authigenic 10Be/9Be ratio can be constrained using appropriate Holocene deposits, but also that this ratio remained relatively constant over the studied time period (i.e. ~ 1 to 8 Ma). In addition, the validity of the calibration demonstrates that the <span class="hlt">sedimentary</span> levels deposited in the Chadian <span class="hlt">Basin</span> during wet periods accompanied by major lacustrine extension in an area otherwise characterized by a recurrent desert climate since at least 8 Ma have remained closed to gain or loss of beryllium other than by radioactive decay in spite of cycles of inundation and desiccation. Fifty-five new or revaluated (using the new published 10Be half-life) authigenic 10Be/9Be deposition ages were obtained along twelve logs distributed out of two West-East cross sections that encompass best representative Mio-Pliocene outcrops including paleontological localities. These authigenic 10Be/9Be deposition ages show a systematic stratigraphic decrease when considering all studied <span class="hlt">sedimentary</span> facies extending from the Pleistocene up to 8 Ma and allow performing geologic correlations otherwise impossible in the studied area. The resulting global sequence evidences and temporally specifies the succession of the main paleoenvironments that have developed in this region since the Miocene. Under the special conditions encountered in the northern Chad <span class="hlt">Basin</span>, this study demonstrates that the authigenic 10Be/9Be ratio may be used as a dating tool of continental <span class="hlt">sedimentary</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.3666R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.3666R"><span><span class="hlt">Sedimentary</span> profile from oxbow lake as an archive for past productivity and vegetation changes: a case study from Ganges <span class="hlt">basin</span>, West Bengal, India</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rakshit, Subhadeep; Ghosh, Sambit; Sanyal, Prasanta; Ambili, Anoop</p> <p>2015-04-01</p> <p>Isotope (δ13CSOM) and biomarker (lipid n-alkane) investigations has been carried out on three <span class="hlt">sedimentary</span> profiles (ca. 1.8 m depth) collected from Mohanpur, West Bengal, India with the aim of reconstructing paleovegetational and paleoproductivity changes. Satellite images reveal that the investigated sediments has been deposited in an oxbow lake setting of the river Ganges. The correlation of the three <span class="hlt">sedimentary</span> profiles has been achieved using lithological and isotopic (δ13CSOM) marker layers. The total organic carbon (TOC) content of the profile ranges from 0.9% to 0.1%. The isotopic analysis (δ13CSOM) shows values mostly fluctuating between -19.2o to -22o with a rapid excursions (~5) showing enriched δ13CSOMvalue (-14.2) observed at ca. 1.5 m depth. The biomarker studies of the profile reveals dominant preferences in short carbon chain (C14, C16, C18, C20) with a little preferences for higher chain (C29, C31, C33). Interestingly, n-alkanes at 1.5 m depth shows very high concentration in short chain n-alkanes. Since the lower chain n-alkane represents aquatic vegetation/productivity and higher chain indicates the terrestrial contribution, the data from the investigated <span class="hlt">sedimentary</span> profile shows contribution mostly from aquatic vegetation with a little contribution from terrestrial plants. This inference has been further corroborated by δ13CSOMvalues (-19.2o to -22) of the <span class="hlt">sedimentary</span> profile typical of mixed aquatic and terrestrial vegetation. Additionally, the enriched δ13CSOMvalue (-14.2) coupled with very high concentration of short chain n-alkanes at 1.5 m depth reveals intense lake eutrophication. The development of rigorous chronology and high resolution data set of additional analytical parameters (e.g., C/N, δ15N) will provide crucial paleoclimate data set from this unexplored setting of Indian summer monsoon domain.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5443329','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5443329"><span>Evolutionary mass-flow megaturbidites in interplate <span class="hlt">basin</span>: example of the North Pyrenean <span class="hlt">basin</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bourrouilh, R.</p> <p>1986-05-01</p> <p>The Cretaceous North Pyrenean interplate <span class="hlt">basin</span> develops in close relationship with the opening of the Bay of Biscay. The <span class="hlt">basin</span> margins and its gravity <span class="hlt">sedimentary</span> filling are related to differential movements of Iberian and European plates. Optimal climatic and morphologic conditions allow <span class="hlt">large</span> amounts of carbonates to be deposited on its margins, major factors provoked the <span class="hlt">sedimentary</span> and tectonic instability of the <span class="hlt">basin</span> shelf and slope, particularly by reactivating a deep, ancient fault network. These events generated a single event or a series of successive autosuspended mass flows, which differentiate into megaturbidites, spreading over <span class="hlt">large</span> areas of the <span class="hlt">basin</span> floor. This <span class="hlt">large</span> distribution of instantaneous evolutionary mass-flow megaturbidites, which pertain to the normal carbonate gravity sedimentation of the <span class="hlt">basin</span>, allows us to determine: (1) paleoenvironments such as areas of paleoslopes; (2) the <span class="hlt">sedimentary</span> and tectonic migration of the shelf break and of the <span class="hlt">basinal</span> depocenter, and the relation of migration to regional plate tectonics; (3) evolution of local areas of special interest (petroleum geology), or evolution of the interplate <span class="hlt">basin</span>, especially when it becomes a single trough (birth of first regional linear sequences); (4) interference of local centered transfer system (i.e., canyon fan or point slope fan) and regional linear transfer system (i.e., shelf break and slope).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1811976Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1811976Q"><span>The role of Natural Flood Management in managing floods in <span class="hlt">large</span> scale <span class="hlt">basins</span> during extreme events</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Quinn, Paul; Owen, Gareth; ODonnell, Greg; Nicholson, Alex; Hetherington, David</p> <p>2016-04-01</p> <p>There is a strong evidence database showing the negative impacts of land use intensification and soil degradation in NW European river <span class="hlt">basins</span> on hydrological response and to flood impact downstream. However, the ability to target zones of high runoff production and the extent to which we can manage flood risk using nature-based flood management solution are less known. A move to planting more trees and having less intense farmed landscapes is part of natural flood management (NFM) solutions and these methods suggest that flood risk can be managed in alternative and more holistic ways. So what local NFM management methods should be used, where in <span class="hlt">large</span> scale <span class="hlt">basin</span> should they be deployed and how does flow is propagate to any point downstream? Generally, how much intervention is needed and will it compromise food production systems? If we are observing record levels of rainfall and flow, for example during Storm Desmond in Dec 2015 in the North West of England, what other flood management options are really needed to complement our traditional defences in <span class="hlt">large</span> <span class="hlt">basins</span> for the future? In this paper we will show examples of NFM interventions in the UK that have impacted at local scale sites. We will demonstrate the impact of interventions at local, sub-catchment (meso-scale) and finally at the <span class="hlt">large</span> scale. These tools include observations, process based models and more generalised Flood Impact Models. Issues of synchronisation and the design level of protection will be debated. By reworking observed rainfall and discharge (runoff) for observed extreme events in the River Eden and River Tyne, during Storm Desmond, we will show how much flood protection is needed in <span class="hlt">large</span> scale <span class="hlt">basins</span>. The research will thus pose a number of key questions as to how floods may have to be managed in <span class="hlt">large</span> scale <span class="hlt">basins</span> in the future. We will seek to support a method of catchment systems engineering that holds water back across the whole landscape as a major opportunity to management water</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016HESS...20.2151K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016HESS...20.2151K"><span>A century-scale, human-induced ecohydrological evolution of wetlands of two <span class="hlt">large</span> river <span class="hlt">basins</span> in Australia (Murray) and China (Yangtze)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kattel, Giri R.; Dong, Xuhui; Yang, Xiangdong</p> <p>2016-06-01</p> <p>Recently, the provision of food and water resources of two of the world's largest river <span class="hlt">basins</span>, the Murray and the Yangtze, has been significantly altered through widespread landscape modification. Long-term <span class="hlt">sedimentary</span> archives, dating back for some centuries from wetlands of these river <span class="hlt">basins</span>, reveal that rapid, <span class="hlt">basin</span>-wide development has reduced the resilience of biological communities, resulting in considerable decline in ecosystem services, including water quality. <span class="hlt">Large</span>-scale human disturbance to river systems, due to river regulation during the mid-20th century, has transformed the hydrology of rivers and wetlands, causing widespread modification of aquatic biological communities. Changes to cladoceran zooplankton (water fleas) were used to assess the historical hydrology and ecology of three Murray and Yangtze river wetlands over the past century. Subfossil assemblages of cladocerans retrieved from sediment cores (94, 45, and 65 cm) of three wetlands: Kings Billabong (Murray), Zhangdu, and Liangzi lakes (Yangtze), showed strong responses to hydrological changes in the river after the mid-20th century. In particular, river regulation caused by construction of dams and weirs together with river channel modifications, has led to significant hydrological alterations. These hydrological disturbances were either (1) a prolonged inundation of wetlands or (2) reduced river flow, both of which caused variability in wetland depth. Inevitably, these phenomena have subsequently transformed the natural wetland habitats, leading to a switch in cladoceran assemblages to species preferring poor water quality, and in some cases to eutrophication. The quantitative and qualitative decline of wetland water conditions is indicative of reduced ecosystem services, and requires effective restoration measures for both river <span class="hlt">basins</span> which have been impacted by recent socioeconomic development and climate change.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006PApGe.163.2141H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006PApGe.163.2141H"><span>Fluid Pressure Variation in a <span class="hlt">Sedimentary</span> Geothermal Reservoir in the North German <span class="hlt">Basin</span>: Case Study Groß Schönebeck</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huenges, Ernst; Trautwein, Ute; Legarth, Björn; Zimmermann, Günter</p> <p>2006-10-01</p> <p>The Rotliegend of the North German <span class="hlt">basin</span> is the target reservoir of an interdisciplinary investigation program to develop a technology for the generation of geothermal electricity from low-enthalpy reservoirs. An in situ downhole laboratory was established in the 4.3 km deep well Groβ Schönebeck with the purpose of developing appropriate stimulation methods to increase permeability of deep aquifers by enhancing or creating secondary porosity and flow paths. The goal is to learn how to enhance the inflow performance of a well from a variety of rock types in low permeable geothermal reservoirs. A change in effective stress due to fluid pressure was observed to be one of the key parameters influencing flow properties both downhole and in laboratory experiments on reservoir rocks. Fluid pressure variation was induced using proppant-gel-frac techniques as well as waterfrac techniques in several different new experiments in the borehole. A pressure step test indicates generation and extension of multiple fractures with closure pressures between 6 and 8.4 MPa above formation pressure. In a 24-hour production test 859 m3 water was produced from depth indicating an increase of productivity in comparison with former tests. Different depth sections and transmissibility values were observed in the borehole depending on fluid pressure. In addition, laboratory experiments were performed on core samples from the sandstone reservoir under uniaxial strain conditions, i.e., no lateral strain, constant axial load. The experiments on the borehole and the laboratory scale were realized on the same rock types under comparable stress conditions with similar pore pressure variations. Nevertheless, stress dependences of permeability are not easy to compare from scale to scale. Laboratory investigations reflect permeability variations due to microstructural heterogeneities and the behavior in the borehole is dominated by the generation of connections to <span class="hlt">large</span>-scale structural patterns.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JAG...133...98K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JAG...133...98K"><span>A case study on pseudo 3-D Chirp sub-bottom profiler (SBP) survey for the detection of a fault trace in shallow <span class="hlt">sedimentary</span> layers at gas hydrate site in the Ulleung <span class="hlt">Basin</span>, East Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, Young-Jun; Koo, Nam-Hyung; Cheong, Snons; Kim, Jung-Ki; Chun, Jong-Hwa; Shin, Sung-Ryul; Riedel, Michael; Lee, Ho-Young</p> <p>2016-10-01</p> <p>A pseudo 3-D Chirp sub-bottom profiler (SBP) survey was conducted to define the extension of a fault that was previously identified on low-resolution 2-D seismic data with an emphasis on the shallow <span class="hlt">sedimentary</span> layers and to determine if the fault extends to the seafloor. The geophysical survey was conducted as part of an environmental impact assessment for a proposed gas hydrate production test in the Ulleung <span class="hlt">Basin</span>, East Sea. The Chirp SBP raw data were acquired over an area of 1 km × 1 km with an average line spacing of 20 m. To produce a 3-D Chirp SBP volume, we developed an optimal processing sequence that was divided into two steps. The first phase of 2-D data processing included a sweep signature estimation, correlation, deconvolution, swell effect correction, and migration. The second phase of 3-D data processing was composed of a bin design, bin gathering of the final processed 2-D data set, amplitude normalization, and residual statics correction. The 3-D Chirp SBP volume provides enhanced imaging especially due to the residual static processing using a moving average method and shows better continuity of the <span class="hlt">sedimentary</span> layers and consistency of the reflection events than the individual 2-D lines. Deformation of the seafloor as a result of the fault was detected, and the fault offset increases in the deeper <span class="hlt">sedimentary</span> layers. We also determined that the fault strikes northwest-southeast. However, the shallow sub-seafloor sediments have high porosities and therefore do not exhibit brittle fault-behavior but rather deform continuously due to fault movement.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19970002904','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19970002904"><span>The <span class="hlt">Large</span> Impact Process Inferred from the Geology of Lunar Multiring <span class="hlt">Basins</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Spudis, Paul D.</p> <p>1994-01-01</p> <p>The study of the geology of multiring impact <span class="hlt">basins</span> on the Moon over the past ten years has given us a rudimentary understanding of how these <span class="hlt">large</span> structures have formed and evolved on the Moon and other bodies. Two-ring <span class="hlt">basins</span> on the Moon begin to form at diameters of about 300 km; the transition diameter at which more than two rings appear is uncertain, but it appears to be between 400 and 500 km in diameter. Inner rings tend to be made up of clusters or aligned segments of massifs and are arranged into a crudely concentric pattern; scarp-like elements may or may not be present. Outer rings are much more scarp-like and massifs are rare to absent. <span class="hlt">Basins</span> display textured deposits, interpreted as ejecta, extending roughly an apparent <span class="hlt">basin</span> radius exterior to the main topographic rim. Ejecta may have various morphologies, ranging from wormy and hummocky deposits to knobby surfaces; the causes of these variations are not known, but may be related to the energy regime in which the ejecta are deposited. Outside the limits of the textured ejecta are found both fields of satellitic craters (secondaries) and light plains deposits. Impact melt sheets are observed on the floors of relatively unflooded <span class="hlt">basins</span>. Samples of impact melts from lunar <span class="hlt">basins</span> have basaltic major-element chemistry, characterized by K, rare-earth elements (REE), P, and other trace elements of varying concentration (KREEP); ages are between 3.8 and 3.9 Ga. These lithologies cannot be produced through the fusion of known pristine (plutonic) rock types, suggesting the occurrence of unknown lithologies within the Moon. These melts were probably generated at middle to lower crustal levels. Ejecta compositions, preservation of pre-<span class="hlt">basin</span> topography, and deposit morphologies all indicate that the excavation cavity of multiring <span class="hlt">basins</span> is between about 0.4 and 0.6 times the diameter of the apparent crater diameter. <span class="hlt">Basin</span> depths of excavation can be inferred from the composition of <span class="hlt">basin</span> ejecta. A variety of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AcGeo..64..398A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AcGeo..64..398A"><span>Comparison of Factorial Kriging Analysis Method and Upward Continuation Filter to Recognize Subsurface Structures — A Case Study: Gravity Data from a Hydrocarbon Field in the Southeast <span class="hlt">Sedimentary</span> <span class="hlt">Basins</span> of the East Vietnam Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Azad, Mohammad-Reza; Koneshloo, Mohammad; Kamakar Rouhani, Abolghasem; Aghajani, Hamid</p> <p>2016-04-01</p> <p>To interpret geophysical anomaly maps, it is necessary to filter out regional and sometimes noise components. Each measured value in a gravity survey consists of different components. Upward continuation (UC) is one of the most widely used filters. The shortcoming of this filter is not to consider the spatial structure of the data, and also the fact that the trial and error approach and expert's judgment are needed to adjust it. This study aims to compare the factorial kriging analysis (FKA) and UC filters for separation of local and regional anomalies in the gravity data of a hydrocarbon field in the southeast <span class="hlt">sedimentary</span> <span class="hlt">basins</span> of the East Vietnam Sea. As shown in this paper, FKA method permits to filter out all of the identified structures, while the UC filter does not possess this capability. Therefore, beside general and classic filtering methods, the FKA method can be used as a strong method in filtering spatial structures and anomaly component.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120008059','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120008059"><span>Improving the Inventory of <span class="hlt">Large</span> Lunar <span class="hlt">Basins</span>: Using Lola Data to Test Previous Candidates and Search for New Ones</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Frey, Herbert V.; Meyer, H. M.</p> <p>2012-01-01</p> <p>Topography and crustal thickness data from LOLA altimetry were used to test the validity of 98 candidate <span class="hlt">large</span> lunar <span class="hlt">basins</span> derived from photogeologic and earlier topographic and crustal thickness data, and to search for possible new candidates. We eliminate 23 previous candidates but find good evidence for 20 new candidates. The number of <span class="hlt">basins</span> > 300 km diameter on the Moon is almost certainly a factor 2 (maybe 3?) larger than the number of named features having <span class="hlt">basin</span>-like topography.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900028055&hterms=peat&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dpeat','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900028055&hterms=peat&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dpeat"><span>Detecting biotic and hydrogeochemical processes in <span class="hlt">large</span> peat <span class="hlt">basins</span> with Landsat TM imagery</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Glaser, Paul H.</p> <p>1989-01-01</p> <p>A survey was made of three <span class="hlt">large</span> peat <span class="hlt">basins</span> in boreal North America with Landsat TM imagery and field sampling. False-color composites composed of Bands 2, 3, and 4 are particularly effective in discriminating the major vegetation types and the important hydrogeochemical processes in these peatlands. This imagery indicates that the discharge o