Sample records for argillo-carbonated sedimentary series

  1. Organic geochemistry of the Callovo-Oxfordian argillo-carbonated sedimentary series of the East of the Paris basin and of England. Variabilities and paleo-environmental implications; Geochimie organique des series argilo-carbonatees du Callovo-Oxfordien de l'Est du bassin de Paris et d'Angleterre: Variabilites et implications paleoenvironnementales

    Energy Technology Data Exchange (ETDEWEB)

    Hautevelle, Y


    The Callovo-Oxfordian clay-stones from the East of the Paris basin are studied by ANDRA in order to test the feasibility of a possible storage of radioactive waste. The molecular analysis of their organic matter indicates that they can be considered as homogenous from their organic content point of view because they are characterized by only one molecular facies. However, the transition to the surrounding limestones is underlined by a major evolution of the molecular facies indicating a change and an increase of the variability of the deposition and diagenesis conditions. The evolution of the distribution of the plant bio-markers indicates, at the end of the Lower Oxfordian, a paleo-floristic change characterized by the increase of the proportion of Pinaceae (a conifer family) or their forerunners on the London-Brabant massif. This paleo-floristic evolution reflects a paleo-climatic change characterized by the increase of aridity at the global scale. Other complementary results get on other sedimentary series of similar ages highlight the occurrence of a period of water anoxia during the Middle Callovian which certainly happened on the major part of the Western Europe. This event could be at the origin of the crisis of the carbonate production at the Dogger/Malm transition. On the other hand, an experimental technique based on artificial maturation of extant plants has been developed and will allow the acquisition of new palaeo-chemo-taxonomic data. These data will contribute to a better interpretation of plant bio-marker assemblages in terms of palaeo-floristic composition. (author)

  2. How much deviations in sampling sedimentary series do impact on the reconstruction of climatic cycles? (United States)

    Martinez, Mathieu; Kotov, Sergey; De Vleeschouwer, David; Pas, Damien; Pälike, Heiko


    Spectral analyses have become a key tool for detecting climatic cycles (like orbital forcing) in sedimentary series. Most of spectral analyses (like Fourier Transforms and derivative, MTM…) require a constant sample step. However, this is rarely achieved when collecting rock samples in outcrops or cores. Uncertainties in the sample positions distort the sedimentary series, which reduces the power spectrum of the short periods, like precession cycles. Here, we provide a tool for assessing how much a distortion in the sampling pattern impacts on the spectral power of a sedimentary series, with special focus on the Milankovitch band. We then assess how precise should be the control of a sample position as well as the required density of samples per precession cycle for reliably assess the spectral power in the whole Milankovitch band. Sample distances are randomised using gamma models to simulate distortions of the sedimentary series. Such approach allows the stratigraphic order of samples to be maintained as well as to parameterise the mean and the variance of the dispersion of the sample distances. We tested this sample distance randomisation on two published geological datasets that have been sampled at different steps. The spectra of the non-distorted and distorted series were calculated using the Lomb-Scargle and the Multi-Taper Method. When randomising sample diatances with an uncertainty of 5% of the mean sample step, all frequencies above ~1/3 of the Nyquist frequency are significantly reduced. At 10% and 15% uncertainty, all frequencies above respectively ~1/5 and ~1/6 of the Nyquist frequency are affected. This test illustrates that a precise stratigraphic control on the sample position as well as collecting at least 6-10 samples per precession cycle are required to reliably estimate the power spectrum in the whole Milankovitch band.

  3. Testing the impact of stratigraphic uncertainty on spectral analyses of sedimentary series (United States)

    Martinez, Mathieu; Kotov, Sergey; De Vleeschouwer, David; Pas, Damien; Pälike, Heiko


    Spectral analysis is a key tool for identifying periodic patterns in sedimentary sequences, including astronomically related orbital signals. While most spectral analysis methods require equally spaced samples, this condition is rarely achieved either in the field or when sampling sediment core. Here, we propose a method to assess the impact of the uncertainty or error made in the measurement of the sample stratigraphic position on the resulting power spectra. We apply a Monte Carlo procedure to randomise the sample steps of depth series using a gamma distribution. Such a distribution preserves the stratigraphic order of samples and allows controlling the average and the variance of the distribution of sample distances after randomisation. We apply the Monte Carlo procedure on two geological datasets and find that gamma distribution of sample distances completely smooths the spectrum at high frequencies and decreases the power and significance levels of the spectral peaks in an important proportion of the spectrum. At 5 % of stratigraphic uncertainty, a small portion of the spectrum is completely smoothed. Taking at least three samples per thinnest cycle of interest should allow this cycle to be still observed in the spectrum, while taking at least four samples per thinnest cycle of interest should allow its significance levels to be preserved in the spectrum. At 10 and 15 % uncertainty, these thresholds increase, and taking at least four samples per thinnest cycle of interest should allow the targeted cycles to be still observed in the spectrum. In addition, taking at least 10 samples per thinnest cycle of interest should allow their significance levels to be preserved. For robust applications of the power spectrum in further studies, we suggest providing a strong control of the measurement of the sample position. A density of 10 samples per putative precession cycle is a safe sampling density for preserving spectral power and significance level in the


    Institute of Scientific and Technical Information of China (English)


    20160899 Chen Ji(School of Energy Resources,China University of Geosciences(Beijing),Beijing 100083,China);Jiang Zaixing Sedimentary Facies Characteristics and Palaeoenvironment of Jurassic Yangye Forma-

  5. Upper Permian Series Tidal Flat Facies Sedimentary Characteristics in Panxian, Guizhou%贵州盘县晚二叠世潮坪相沉积特征

    Institute of Scientific and Technical Information of China (English)

    王先超; 范士彦; 邵玉宝; 王怀勐


    Through analysis of data from Upper Permian boreholes in Panxian, Guizhou has identified the tidal flat sediments are main-ly terrigenous clastic sediments, on the bases of sedimentary petrological, sedimentological, paleontological and historic geological, as well as sedimentary geochemical indicators can be subdivided into five microfacies of sand flat, mixed flat, mud flat, peat flat and tidal creek. The analysis considered that tidal flat sediments have developed regressive type prograding sequence with sediment grain size finer as a whole, better sorted, developed tidal bedding. In mixed flat, mud flat and peat flat microfacies, mudstone geochemical parame-ters of V/(V+Ni)、Sr/Ba、U/Th、V/Cr、Ni/Co、Ceanom indicated each microfacies sedimentary water body oxygen deficit-oxygen poor-oxidi-zation state, oxygen poor-oxidization state and deoxidization-oxygen poor-oxygen deficit-oxidization state, thus tally with geological settings.%通过对贵州盘县上二叠统钻井资料的研究分析,基于沉积岩石学、沉积学、古生物地史学及沉积地球化学等相标志识别出潮坪沉积以陆源碎屑沉积为主,可细分为砂坪、混合坪、泥坪、泥炭坪和潮沟等5种微相。分析认为:潮坪沉积发育海退型进积层序,沉积物粒度整体较细,分选性较好,发育潮汐层理;混合坪、泥坪、泥炭坪微相泥岩中V/(V+Ni)、Sr/Ba、U/Th、V/Cr、Ni/Co、Ceanom等地球化学参数指示了各微相沉积水体的缺氧-贫氧-氧化状态、贫氧-氧化状态和还原-贫氧-缺氧-氧化状态,与地质背景吻合性好。

  6. 缅甸某区块始新统沉积相对储层的控制作用分析%On How the Eocene Series Sedimentary Facies in the Studied Area in Burma Affect Reservoirs' Quality

    Institute of Scientific and Technical Information of China (English)

    王进; 王海鹏; 曾庆立


    The targeted area under research situated in the middle of Irrawaddy Basin, Burma, is a favorable place for oil gas exploration. By studying the characteristics of reservoirs in different sedimentary fades of Eocene series in the researched area, this paper points out that the underwater distributary channels are the best reservoir development microfacies followed by distributary channels, braided channel and river mouth bars while natural levees and splay sand bodies have low reservoir quality which unveils the fact that sedimentary fades do influence the development of reservoirs to some extent.%研究区位于缅甸伊洛瓦底盆地中部,是油气勘探的有利地区。通过对研究区始新统不同沉积相带储层特征研究,认为水下分流河道为最有利的储层发育微相;分流河道、辫状河道、河口坝次之;天然堤、决口扇砂体的储层性质相对较差,反映了沉积相对储层的发育特征有一定的控制作用。

  7. Evolution of Sedimentary Rocks (United States)

    Veizer, J.; MacKenzie, F. T.


    For almost a century, it has been recognized that the present-day thickness and areal extent of Phanerozoic sedimentary strata increase progressively with decreasing geologic age. This pattern has been interpreted either as reflecting an increase in the rate of sedimentation toward the present (Barrell, 1917; Schuchert, 1931; Ronov, 1976) or as resulting from better preservation of the younger part of the geologic record ( Gilluly, 1949; Gregor, 1968; Garrels and Mackenzie, 1971a; Veizer and Jansen, 1979, 1985).Study of the rocks themselves led to similarly opposing conclusions. The observed secular (=age) variations in relative proportions of lithological types and in chemistry of sedimentary rocks (Daly, 1909; Vinogradov et al., 1952; Nanz, 1953; Engel, 1963; Strakhov, 1964, 1969; Ronov, 1964, 1982) were mostly given an evolutionary interpretation. An opposing, uniformitarian, approach was proposed by Garrels and Mackenzie (1971a). For most isotopes, the consensus favors deviations from the present-day steady state as the likely cause of secular trends.This chapter attempts to show that recycling and evolution are not opposing, but complementary, concepts. It will concentrate on the lithological and chemical attributes of sediments, but not deal with the evolution of sedimentary mineral deposits (Veizer et al., 1989) and of life ( Sepkoski, 1989), both well amenable to the outlined conceptual treatment. The chapter relies heavily on Veizer (1988a) for the sections dealing with general recycling concepts, on Veizer (2003) for the discussion of isotopic evolution of seawater, and on Morse and Mackenzie (1990) and Mackenzie and Morse (1992) for discussion of carbonate rock recycling and environmental attributes.

  8. Member 1 of Yongji Formation (Ey1) sedimentary characteristics and its origin analysis in Yitong Graben

    Institute of Scientific and Technical Information of China (English)


    Ey1 has the unique desultory-weak or gap seismic reflection structure as its one of the most important characteristics. It is very important to clarify sedimentary characteristics and its origin for Yitong Graben and its sedimentary facies and tectonic evolution. On the basis of the research of core analyses, well logging data analyses, sedimentary facies analyses and seismic reflection structure analyses, the authors have concluded the sedimentary characteristics of Ey1, and have carried out Ey1 sedimentary environments and its origin. The result shows that Ey1 desultory-weak or gap seismic reflection may be a series of small scale secondary sediment fans superimposition.

  9. Sedimentary condensation and authigenesis (United States)

    Föllmi, Karl


    Most marine authigenic minerals form in sediments, which are subjected to condensation. Condensation processes lead to the formation of well individualized, extremely thin ( 100ky), and which experienced authigenesis and the precipitation of glaucony, verdine, phosphate, iron and manganese oxyhydroxides, iron sulfide, carbonate and/or silica. They usually show complex internal stratigraphies, which result from an interplay of sediment accumulation, halts in sedimentation, sediment winnowing, erosion, reworking and bypass. They may include amalgamated faunas of different origin and age. Hardgrounds may be part of condensed beds and may embody strongly condensed beds by themselves. Sedimentary condensation is the result of a hydrodynamically active depositional regime, in which sediment accumulation, winnowing, erosion, reworking and bypass are processes, which alternate as a function of changes in the location and intensity of currents, and/or as the result of episodic high-energy events engendered by storms and gravity flow. Sedimentary condensation has been and still is a widespread phenomenon in past and present-day oceans. The present-day distribution of glaucony and verdine-rich sediments on shelves and upper slopes, phosphate-rich sediments and phosphorite on outer shelves and upper slopes, ferromanganese crusts on slopes, seamounts and submarine plateaus, and ferromanganese nodules on abyssal seafloors is a good indication of the importance of condensation processes today. In the past, we may add the occurrence of oolitic ironstone, carbonate hardgrounds, and eventually also silica layers in banded iron formations as indicators of the importance of condensation processes. Besides their economic value, condensed sediments are useful both as a carrier of geochemical proxies of paleoceanographic and paleoenvironmental change, as well as the product of episodes of paleoceanographic and paleoenvironmental change themselves.

  10. Quantitative characterisation of sedimentary grains (United States)

    Tunwal, Mohit; Mulchrone, Kieran F.; Meere, Patrick A.


    Analysis of sedimentary texture helps in determining the formation, transportation and deposition processes of sedimentary rocks. Grain size analysis is traditionally quantitative, whereas grain shape analysis is largely qualitative. A semi-automated approach to quantitatively analyse shape and size of sand sized sedimentary 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 Basin, 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 sedimentary environments.

  11. Sedimentary pyrite formation: An update (United States)

    Berner, Robert A.


    Sedimentary pyrite formation during early diagenesis is a major process for controlling the oxygen level of the atmosphere and the sulfate concentration in seawater over geologic time. The amount of pyrite that may form in a sediment is limited by the rates of supply of decomposable organic matter, dissolved sulfate, and reactive detrital iron minerals. Organic matter appears to be the major control on pyrite formation in normal (non-euxinic) terrigenous marine sediments where dissolved sulfate and iron minerals are abundant. By contrast, pyrite formation in non-marine, freshwater sediments is severely limited by low concentrations of sulfate and this characteristic can be used to distinguish ancient organic-rich fresh water shales from marine shales. Under marine euxinic conditions sufficient H 2S is produced that the dominant control on pyrite formation is the availability of reactive iron minerals. Calculations, based on a sulfur isotope model, indicate that over Phanerozoic time the worldwide average organic carbon-to-pyrite sulfur ratio of sedimentary rocks has varied considerably. High C/S ratios during Permo-Carboniferous time can be explained by a shift of major organic deposition from the oceans to the land which resulted in the formation of vast coal swamps at that time. Low C/S ratios, compared to today, during the early Paleozoic can be explained in terms of a greater abundance of euxinic basins combined with deposition of a more reactive type of organic matter in the remaining oxygenated portions of the ocean. The latter could have been due to lower oceanic oxygen levels and/or a lack of transportation of refractory terrestrial organic matter to the marine environment due to the absence of vascular land plants at that time.

  12. Geodynamic evolution of early Mesozoic sedimentary basins in eastern Australia (United States)

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


    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.

  13. Elastic Properties of Sedimentary Rocks (United States)

    Melendez Martinez, Jaime

    Sedimentary rocks are an important research topic since such rocks are associated to sources of ground water as well as oil, gas, and mineral reservoirs. In this work, elastic and physical properties of a variety of sedimentary samples that include glacial sediments, carbonates, shales, one evaporite, and one argillite from a variety of locations are investigated. Assuming vertical transverse isotropy, ultrasonic compressional- and shear-waves (at 1 MHz central frequency) were measured as a function of confining pressure on all samples with the exception of glacial samples which were tested assuming isotropy. Tensile strength tests (Brazilian test) were also carried out on selected glacial samples and, in addition, static-train measurements were conducted on shales and argillite samples. Lithological and textural features of samples were obtained through thin section techniques, scanning electron microscopy images and micro-tomography images. X-ray diffraction and X-Ray fluorescence provided the mineralogical oxides content information. Porosity, density, and pore structure were studied by using a mercury intrusion porosimeter and a helium pycnometer. The wide range of porosities of the studied samples (ranging from a minimum of 1% for shales to a maximum 45% for some glacial sediments) influence the measured velocities since high porosity sample shows an noticeable velocity increment as confining pressure increases as a consequence of closure of microcracks and pores, unlike low porosity samples where increment is quasi-lineal. Implementation of Gassmann's relation to ultrasonic velocities obtained from glacial samples has negligible impact on them when assuming water saturated samples, which suggests that state of saturation it is no so important in defining such velocities and instead they are mainly frame-controlled. On the other hand, velocities measured on carbonate and evaporite samples show that samples are at best weak anisotropic, thus the intrinsic

  14. Correspondence Between Astronomical Periods and Sedimentary Cycles

    Institute of Scientific and Technical Information of China (English)

    Cheng Rihui; You Haitao


    It is shown from detailed study that there are some genetic relationships between outer events of celestial bodies and inner geological events of the earth, such as some kinds of correspondences between astronomical periods and sedimentary cycles. The time spans of movement periods of the solar system around the center of the galaxy and cross the plain of the galaxy, the periods of the earth orbit (Milankovitch period) and periods of sunspot are coincided with that of respective sedimentary cycles. It is suggested that the gravity and magnetic changes of the earth leading up to the global climatic and sea level changes are the dynamics of sedimentary cycles.

  15. Layer Formation in Sedimentary Fingering Convection

    CERN Document Server

    Reali, J F; Alsinan, A; Meiburg, E


    When particles settle through a stable temperature or salinity gradient they can drive an instability known as sedimentary fingering convection. This phenomenon is thought to occur beneath sediment-rich river plumes in lakes and oceans, in the context of marine snow where decaying organic materials serve as the suspended particles, or in the atmosphere in the presence of aerosols or volcanic ash. Laboratory experiments of Houk and Green (1973) and Green (1987) have shown sedimentary fingering convection to be similar to the more commonly known thermohaline fingering convection in many ways. Here, we study the phenomenon using 3D direct numerical simulations. We find evidence for layer formation in sedimentary fingering convection in regions of parameter space where it does not occur for non-sedimentary systems. This is due to two complementary effects. Sedimentation affects the turbulent fluxes and broadens the region of parameter space unstable to the $\\gamma$-instability (Radko 2003) to include systems at l...

  16. The Multiple Factors and Multiple Stages Involved in Sedimentary Ore Genesis

    Institute of Scientific and Technical Information of China (English)

    叶连俊; 陈其英


    Sedimentary mineral deposits cannot be formed by any kind of simple chemical reactions,but are products of a complex multi-episodic process depending on multiple factors,The whole process is governed by a combination of sedimentary,geochemical,biogeochemical,organic geochemical,paleoclimatical,mechanical agents as well as by the properties of relevant earth crust segment and its structural making up and tectonic mobility A Sedimentary ore deposit is nothing but a special kind of sedimentary facies,characterized by definite sedimentary assemblages,Different genetic types of ore deposit and different ore associations characterize different sedimentary assemblages in different ore-forming belts.Crustal movement,including orogenic,epeirogenic and,oparticularly eustatic events,controls the formation and distribution of all kinds of sedimentary mineral deposits,most of which occur within the transgression front in the lower part of marine transpressive series.Mineral deposits of economic importance cannot be precipitated directly from sea water,but are products of terrestrial imbibition,biological enrichment and pore water concentration instead,Deposits formed above the wave base in the inner continental shelf under strong dynamic condition of sea water are often large and predominantly clastic in texture with commercial grade.Below the wave base in the outer continental shelf environment,where it is more or less dynamically stagnant and oxygen-deficient,the resulted in dustrial ore deposits are mostly of diagenetic or strata-bound type,formed through deep-burying diagenesis.The theory of multi-factor and multi-episodic metallogenesis includes three major aspects:the ore-forming process,the sedimentary environment and the geological background.The study of the forma tion process itself and the sources of ore-forming elements would provide useful clues to further prospectiong Whereas,invstigations of the sedimentary environments should shed light on the spacial

  17. Tectonic and sedimentary evolution of Bransfield Basin, Antarctica

    Energy Technology Data Exchange (ETDEWEB)

    Jeffers, J.D.; Thomas, M.A.; Anderson, J.B.


    The Bransfield basin is the youngest and best developed of a series of extensional marginal basins on the Pacific margin of the Antarctic Peninsular. Marine geophysical data collected over five seasons show that the back arc is segmented laterally into three subbasins separated by transform zones. These subbasins differ in width, depth, structural style, and seisimicity and are correlated with three different age segments of subducted sea floor. The distribution of principal sedimentary environments, identified from high-resolution seismic reflection data, and their associated lithofacies, seen in piston cores and surface sediment samples, is controlled largely by the tectonic segmentation of the basins. Terrigenous sediments prograde into the basin from the continent side, whereas sediment gravity-flow processes deliver volcaniclastic material from the arc to slope-base aprons and to fan lobes at the outlets of fiords. Organic-rich muds fill the deep basin; their proximity to submarine volcanic centers produces thermogenic hydrocarbons. Understanding the recent tectonic and sedimentary evolution of the Bransfield basin may help refine interpretations of the older deformed marginal basin sequences of southern South America, the Scotia Arc, and the Antarctic Peninsula.

  18. Sedimentary Environments Offshore Norway - Palaeozoic to Recent

    Energy Technology Data Exchange (ETDEWEB)

    Martinsen, Ole J.; Dreyer, Tom [eds.


    The report includes the extended abstracts from the conference, 71 in number. The presentations discuss the sedimentary characteristics of the North Sea area and the the methods used in the research, a thorough knowledge of which is important for economic exploration of the oil and gas resources of the North Sea.

  19. Sedimentary porphyrins: Correlations with biological precursors

    Energy Technology Data Exchange (ETDEWEB)

    Callot, H.J.; Ocampo, R.; Albrecht, P. (Universite Louis Pasteur, Strasbourg (France))

    Over the past 6 years several sedimentary porphyrins (petroporphyrins, geoporphyrins) were correlated for the first time with biological precursors specific for classes of organisms (algae, photosynthetic bacteria (Chlorobiaceae)). This article discusses the various examples of correlations and the methods that led to these conclusions (isolation of pure porphyrins, structure determination using spectroscopic techniques, total synthesis, isotope measurements).

  20. Geochemistry of Fine-grained Sediments and Sedimentary Rocks (United States)

    Sageman, B. B.; Lyons, T. W.


    , 1981; Berner et al., 1983; Kump et al., 2000), with a shifting emphasis toward sophisticated characterization of the linkages among solid Earth, oceans, biosphere, cryosphere, atmosphere, and climate, mediated by short- and long-term biogeochemical cycles. As a result, one of the primary objectives of current geological inquiry is improved understanding of the interconnectedness and associated feedback among the cycles of carbon, nitrogen, phosphorous, oxygen, and sulfur, and their relationship to the history of Earth's climate. This "Earth System" approach involves uniformitarian extrapolations of knowledge gained from modern environments to proxy-based interpretations of environmental change recorded in ancient strata. The strength of modern data lies with direct observations of pathways and products of physical, chemical, and biological processes, but available time-series are short relative to the response times of many of the biogeochemical systems under study. By contrast, stratigraphically constrained geological data offer time-series that encompass a much fuller range of system response. But with the enhanced breadth of temporal resolution and signal amplitude provided by ancient sedimentary records comes a caveat - we must account for the blurring of primary paleo-environmental signals by preservational artifacts and understand that proxy calibrations are extended from the modern world into a nonsubstantively uniformitarian geological past.Fortunately, detrital sedimentary rocks preserve records of multiple proxies (dependent and independent) that illuminate the processes and conditions of sediment formation, transport, deposition, and burial. An integrated multiproxy approach offers an effective tool for deconvolving the history of biogeochemical cycling of, among other things, carbon and sulfur, and for understanding the range of associated paleo-environmental conditions (e.g., levels of atmospheric oxygen and carbon dioxide, oceanic paleoredox, and

  1. Fourier series

    CERN Document Server

    Tolstov, Georgi P


    Richard A. Silverman's series of translations of outstanding Russian textbooks and monographs is well-known to people in the fields of mathematics, physics, and engineering. The present book is another excellent text from this series, a valuable addition to the English-language literature on Fourier series.This edition is organized into nine well-defined chapters: Trigonometric Fourier Series, Orthogonal Systems, Convergence of Trigonometric Fourier Series, Trigonometric Series with Decreasing Coefficients, Operations on Fourier Series, Summation of Trigonometric Fourier Series, Double Fourie

  2. Understanding and modeling the sedimentary system


    Hay, William W


    The sedimentary system involves processes that weather rocks and reduce them to soluble and fine-grained particulate components that can be transported. deposited, and transformed back into rock. !Jost of the processes can be observed today, but the present is an unusual episode in our planet's history. We live in a brief warm interglacial epi sode in an interval usually characterized by large mid-and high-latitude icc sheets and a much lower sea level. To com...


    Directory of Open Access Journals (Sweden)

    G. I. Leychenkov


    Full Text Available In early February 2012, the drill hole at the Vostok Station encountered theLakeVostokwater. This step is important to study the lake composition including possible microbial life and to model subglacial environments however, the next ambitious target of the Vostok Drilling Project is sampling of bottom sediments, which contain the unique record of ice sheet evolution and environmental changes in centralAntarcticafor millions of years. In this connection, the forecast of sedimentary succession based on existing geophysical data, study of mineral inclusions in the accretion ice cores and tectonic models is important task. Interpretation of Airborne geophysical data suggests thatLakeVostokis the part of spacious rift system, which exists at least from Cretaceous. Reflection and refraction seismic experiments conducted in the southern part ofLakeVostokshow very thin (200–300 m stratified sedimentary cover overlying crystalline basement with velocity of 6.0–6.2 km/s. At present, deposition in southernLakeVostokis absent and similar conditions occurred likely at least last3 m.y. when ice sheet aboveLakeVostokchanged insignificantly. It can be also inferred that from the Late Miocene the rate of deposition inLakeVostokwas extremely low and so the most of sedimentary section is older being possibly of Oligocene to early to middle Miocene age when ice sheet oscillated and deposition was more vigorous. If so, the sampling of upper few meters of this condensed section is very informative in terms of history of Antarctic glaciation. Small thickness of sedimentary cover raises a question about existence of lake (rift depression during preglacial and early glacial times.

  4. Sedimentary input of trace metals from the Chukchi Shelf (United States)

    Aguilar-Islas, A. M.; Seguré, M.; Rember, R.; Nishino, S.


    The distribution of trace metals in the Arctic Ocean has implications for their global cycles, yet until recently few trace metal observations were available from this rapidly changing ocean. Profiles of dissolved Fe from recent Japanese field efforts in the Western Canada Basin (2008, 2010) indicate the broad Chukchi Shelf as a source of Fe to the halocline of the Western Canada Basin. Here we present dissolved and particulate data for crustal (Al, Mn, Fe) and non-crustal elements (Co, Cu, Zn) from the productive Chukchi Sea to characterize the sedimentary input of these metals to shelf waters contributing to the halocline layer of the Canada Basin. Water column profiles were collected in late summer 2013 onboard the R/V Mirai at 10 stations from the Bering Strait to the slope, and at a time-series (10 days) station located over the outer shelf. A narrow and variable (5-10 m) benthic boundary layer was sampled at the time-series station with highly elevated dissolved and suspended particulate metal concentrations. High metal concentrations were also observed in the subsurface at a station over Barrow Canyon where mixing is enhanced. Reactivity of suspended particulate metals was determined by the leachable vs. refractory fractions. Metal concentrations were determined by ICP-MS. Trace metal transport from the shelf to the interior will be discussed in context with shelf mechanisms contributing to this export, and to expected future changes in the Arctic Ocean.

  5. Estimation of sedimentary proxy records together with associated uncertainty

    Directory of Open Access Journals (Sweden)

    B. Goswami


    Full Text Available Sedimentary proxy records constitute a significant portion of the recorded evidence that allow us to investigate paleoclimatic conditions and variability. However, uncertainties in the dating of proxy archives limit our ability to fix the timing of past events and interpret proxy record inter-comparisons. While there are various age-modeling approaches to improve the estimation of the age-depth relations of archives, relatively less focus has been given to the propagation of the age (and radiocarbon calibration uncertainties into the final proxy record. We present a generic Bayesian framework to estimate proxy records along with their associated uncertainty starting with the radiometric age-depth and proxy-depth measurements, and a radiometric calibration curve if required. We provide analytical expressions for the posterior proxy probability distributions at any given calendar age, from which the expected proxy values and their uncertainty can be estimated. We illustrate our method using two synthetic datasets and then use it to construct the proxy records for groundwater inflow and surface erosion from Lonar lake in central India. Our analysis reveals interrelations between the uncertainty of the proxy record over time and the variance of proxy along the depth of the archive. For the Lonar lake proxies, we show that, rather than the age uncertainties, it is the proxy variance combined with calibration uncertainty that accounts for most of the final uncertainty. We represent the proxy records as probability distributions on a precise, error-free time scale that makes further time series analyses and inter-comparison of proxies relatively simpler and clearer. Our approach provides a coherent understanding of age uncertainties within sedimentary proxy records that involve radiometric dating. It can be potentially used within existing age modeling structures to bring forth a reliable and consistent framework for proxy record estimation.

  6. Technical Note: n-Alkane lipid biomarkers in loess: post-sedimentary or syn-sedimentary?

    Directory of Open Access Journals (Sweden)

    D. Faust


    Full Text Available There is an ongoing discussion whether n-alkane biomarkers – and organic matter (OM from loess in general – reflect a syn-sedimentary paleoenvironmental and paleoclimate signal or whether they are significantly a post-sedimentary feature contaminated by root-derived OM. We present first radiocarbon data for the n-alkane fraction of lipid extracts and for the first time luminescence ages for the Middle to Late Weichselian loess-paleosol sequence of Gleina in Saxony, Germany. Comparison of these biomarker ages with sedimentation ages as assessed by optically stimulated luminescence (OSL dating shows that one n-alkane sample features a syn-sedimentary age (14C: 29.2 ± 1.4 kyr cal BP versus OSL: 27.3 ± 3.0 kyr. By contrast, the 14C ages derived from the other n-alkane samples are clearly younger (20.3 ± 0.7 kyr cal BP, 22.1 ± 0.7 kyr cal BP and 29.8 ± 1.4 kyr cal BP than the corresponding OSL ages (26.6 ± 3.1 kyr, 32.0 ± 3.5 kyr and 45.6 ± 5.3 kyr. This finding suggests that a post-sedimentary n-alkane contamination presumably by roots has occurred. In order to estimate the post-sedimentary n-alkane contamination more quantitatively, we applied a 14C mass balance calculation based on the measured pMC (percent modern carbon values, the calculated syn-sedimentary pMC values and pMC values suspected to reflect likely time points of post-sedimentary contamination (current, modern, 3 kyr, 6 kyr and 9 kyr. Accordingly, current and modern root-contamination would account for up to 7%, a 3 kyr old root-contamination for up to 10%, and an Early and Middle Holocene root-contamination for up to 20% of the total sedimentary n-alkane pool. We acknowledge and encourage that these first radiocarbon results need further confirmation both from other loess-paleosol sequences and for different biomarkers, e.g. carboxylic acids or alcohols as further lipid biomarkers.

  7. Sedimentological study of the Meirama Tertiary basin - an example of a sedimentary basin over a strike-slip fault

    Energy Technology Data Exchange (ETDEWEB)

    Monge Ganuzas, C.


    The sedimentary basin of Meirama (Coruna, N.W. Spain), is developed over a strike slip fault of regional extent, whose movements controlled in the past the character and sedimentation processes there and determined the basin morphology and the deformation suffered by the sediments. The sedimentary register at Meirama is represented by one essentially lignitiferous unit and three other terrigenous-detrital. The nature and facies shown by the sediments are not constant within one unit and depend fundamentally on the source area for each unit, either the metasediments of Ordes (Ordenes) Serie (S-Se marginal basin) or the granodiorite of Xalo unit (N-NW marginal basin).

  8. The sedimentary structure of linear sand dunes (United States)

    Bristow; Bailey; Lancaster


    Linear sand dunes--dunes that extend parallel to each other rather than in star-like or crescentic forms--are the most abundant type of desert sand dune. But because their development and their internal structure are poorly understood, they are rarely recognized in the rock record. Models of linear dune development have not been able to take into account the sub-surface structure of existing dunes, but have relied instead either on the extrapolation of short-term measurements of winds and sediment transport or on observations of near-surface internal sedimentary structures. From such studies, it has not been clear if linear dunes can migrate laterally. Here we present images produced by ground penetrating radar showing the three-dimensional sedimentary structure of a linear dune in the Namib sand sea, where some of the world's largest linear dunes are situated. These profiles show clear evidence for lateral migration in a linear dune. Moreover, the migration of a sinuous crest-line along the dune produces divergent sets of cross-stratification, which can become stacked as the dune height increases, and large linear dunes can support superimposed dunes that produce stacked sets of trough cross-stratification. These clear structural signatures of linear dunes should facilitate their recognition in geological records.

  9. Geothermal resources of California sedimentary basins (United States)

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


    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 (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.

  10. Time Series


    Gil-Alana, L.A.; Moreno, A; Pérez-de-Gracia, F. (Fernando)


    The last 20 years have witnessed a considerable increase in the use of time series techniques in econometrics. The articles in this important set have been chosen to illustrate the main themes in time series work as it relates to econometrics. The editor has written a new concise introduction to accompany the articles. Sections covered include: Ad Hoc Forecasting Procedures, ARIMA Modelling, Structural Time Series Models, Unit Roots, Detrending and Non-stationarity, Seasonality, Seasonal Adju...

  11. Ancient sedimentary environments and their subsurface diagnosis, third edition

    Energy Technology Data Exchange (ETDEWEB)

    Selley, R.C.


    All the worlds coal, most of its petroleum, and many ore deposits occur within sedimentary rocks (sandstones, limestones and shales). The distribution of these minerals is closely related to the sedimentary environment of the host rock. For example, an oil field trapped in an old beach sand will be elongated parallel to the basin margin, while a bed of coal within an abandoned river channel will trend into the basin. This book shows how to diagnose the depositional environments of sedimentary rocks and indicates how this knowledge may be applied to the search for petroleum, coal and sedimentary ore deposits. The first edition of this book appeared in 1970. It was primarily concerned with the interpretation of sedimentary environments from outcrop, from an aesthetic stance, with no thought of vulgar commercial application. The second edition (1977) reflected the author's experience in the oil industry and included sections on the use of geophysical well logs in subsurface facies analysis. In recent years the field that is loosely termed seismic stratigraphy developed, where sedimentary concepts are applied to the interpretation of seismic data. Today seismic surveys may delineate channels, deltas, reefs, submarine fans, and other deposits. The thrid edition contains sections on the seismic characteristics of the various sedimentary facies, and the sections on metalliferous sedimentary deposits and recent environments have been expanded.

  12. A Method for Determining Sedimentary Micro-Facies Belts Automatically

    Institute of Scientific and Technical Information of China (English)

    Linfu Xue; Qitai Mei; Quan Sun


    It is important to understand the distribution of sedimentary facies, especially the distribution of sand body that is the key for oil production and exploration. The secondary oil recovery requires analyzing a great deal of data accumulated within decades of oil field development. At many cases sedimentary micro-facies maps need to be reconstructed and redrawn frequently, which is time-consuming and heavy. This paper presents an integrated approach for determining the distribution of sedimentary micro-facies, tracing the micro-facies boundary, and drawing the map of sedimentary micro-facies belts automatically by computer technique. The approach is based on the division and correlation of strata of multiple wells as well as analysis of sedimentary facies. The approach includes transform, gridding, interpolation, superposing, searching boundary and drawing the map of sedimentary facies belts, and employs the spatial interpolation method and "worm" interpolation method to determine the distribution of sedimentary micro-facies including sand ribbon and/or sand blanket. The computer software developed on the basis of the above principle provides a tool for quick visualization and understanding the distribution of sedimentary micro-facies and reservoir. Satisfied results have been achieveed by applying the technique to the Putaohua Oil Field in Songliao Basin, China.

  13. Sedimentary charateristics and hydrocarbon accumulation in Northeast Sichuan basin

    Institute of Scientific and Technical Information of China (English)

    Jianming LI; Xiling WU; Rufeng LI; Liangjie TANG; Lei LI


    Northeast Sichuan basin is a Mesozoic-Cenozoic basin in the northern margin of the Yangtze plate which has a complex tectonic background and hydrocarbon accumulation history.By means of the analysis method of wave processes,major cycles of sedimentary wave process in this basin have been studied.The results show that there are five-order cycles corresponding to 760,220,100,35 and 20 Ma respectively,two first-order sedimentary cycles (220 Ma) and four secondorder sedimentary cycles (100 Ma).The authors find that the second-order sedimentary cycles are well matched with reservoir formation cycles through studying the relationship between second-order sedimentary cycles and reservoir formation cycles,and divide three reservoir formation cycles in this basin.

  14. Chart Series (United States)

    U.S. Department of Health & Human Services — The Centers for Medicare and Medicaid Services (CMS) offers several different Chart Series with data on beneficiary health status, spending, operations, and quality...

  15. Sedimentary environment indicators: Benzothiazole and its derivatives

    Institute of Scientific and Technical Information of China (English)


    Benzothiazoles distributional characteristics of crude oils and non-hydrocarbon fractions of source rocks in Mangya depression of the Qaidam Basin, Lunnan oil field in the Tarim Basin, Kelamayi oil field in the Junggar Basin and the Tulufan Basin oil field were analyzed. It was found that the distributions of benzothiazole are remarkable diversity in different sedimentary environmental oils. The swamp crude oils contain high quantity of benzothiazole and relatively high quantity of alkylthio-benzothiazole and 2(3H)-benzothiazolone. But the quantity of the 2,2′-dithiobis- ben-zothiazole is relatively low. The abundance of benzothiazole and 2,2′-dithiobis-benzothiazole are relatively high in semi-brackish water lacustrine crude oils, but the quantity of alkylthio-benzothiazole and 2(3H)-benzothiazolone are rela-tively low. The benzothiazoles belong to weak acid and mild base compound, and their stabilization conditions relate to their environmental medium. The nitrogenous bases are in favor of alkalescence environment, while weak acid nitroge-nous compounds are the main stable products under the weak acid environment. Benzothiazoles have great signifi-cance in identifying the oil- and gas-formed environment and the geochemistry study of non-hydrocarbon fraction in the future.

  16. Sedimentary Geothermal Feasibility Study: October 2016

    Energy Technology Data Exchange (ETDEWEB)

    Augustine, Chad [National Renewable Energy Lab. (NREL), Golden, CO (United States); Zerpa, Luis [Colorado School of Mines, Golden, CO (United States)


    The objective of this project is to analyze the feasibility of commercial geothermal projects using numerical reservoir simulation, considering a sedimentary reservoir with low permeability that requires productivity enhancement. A commercial thermal reservoir simulator (STARS, from Computer Modeling Group, CMG) is used in this work for numerical modeling. In the first stage of this project (FY14), a hypothetical numerical reservoir model was developed, and validated against an analytical solution. The following model parameters were considered to obtain an acceptable match between the numerical and analytical solutions: grid block size, time step and reservoir areal dimensions; the latter related to boundary effects on the numerical solution. Systematic model runs showed that insufficient grid sizing generates numerical dispersion that causes the numerical model to underestimate the thermal breakthrough time compared to the analytic model. As grid sizing is decreased, the model results converge on a solution. Likewise, insufficient reservoir model area introduces boundary effects in the numerical solution that cause the model results to differ from the analytical solution.

  17. 京津晋冀寒武系第三统鲕粒灰岩特征及其环境意义%The Third Series of Cambrian Oolitic Limestones and Their Sedimentary Environment in Beijing,Tianjin,Shanxi and Hebei Provinces,North China

    Institute of Scientific and Technical Information of China (English)

    赵鹏沄; 刘波; 秦善


    The study area,geographically including Beijing,Tianjin,Shanxi and Hebei Provinces,is the main part of the North China Plate.Based on the study of outcrop and thin section observation,the distribution pattern of oolitic limestone and its ooid characteristics are presented.Olitic limestones were widely distributed in the area during the Third Series of Cambrian.Generally,the oolitic limestone elevates in strata gradually from east to west,which indicates that the oolitic limestone is diachronous.Huge oolitic shoals distribute along a western ward bulging belt from north to south,and mainly are composed of concentric ooids.In west of the belt,the thickness of the oolitic limestone decreases rapidly,and the oolitic limestone mainly is composed of radial ooids.In east of the belt,the oolitic limestone thins gradually,with majority grains of concentric ooids.The marine transgression during the Third Epoch of Cambrian took place from east to west on the North China Plate.In this background,the inner ramp ooid shoals developed in the central belt of the study area,with open sea in the east and shoal back tidal flat in the west.%京津晋冀地区是华北板块的主体,该区寒武系第三统以鲕粒灰岩的广泛发育为特点。通过野外露头剖面和室内薄片观察,对研究区鲕粒灰岩空间展布和鲕粒类型进行了详细研究。鲕粒灰岩从东到西出现的层位逐渐抬高,具有明显的穿时性。大型鲕滩呈向西凸出的弧形带状分布,鲕滩带主体由同心鲕鲕粒灰岩组成,鲕滩带西侧鲕粒灰岩厚度迅速减小,鲕粒以放射鲕居多,鲕滩带东侧鲕粒灰岩厚度逐渐减小,鲕粒以同心鲕占绝对优势。寒武纪第三世海侵方向是由东向西,在研究区中部发育内缓坡的鲕粒滩环境,西部为滩后潮坪环境,东部为开阔海环境。

  18. Archaen to Recent aeolian sand systems and their sedimentary record

    DEFF Research Database (Denmark)

    Rodríguez-López, Juan Pedro; Clemmensen, Lars B; Lancaster, Nick


    The sedimentary record of aeolian sand systems extends from the Archean to the Quaternary, yet current understanding of aeolian sedimentary processes and product remains limited. Most preserved aeolian successions represent inland sand-sea or dunefield (erg) deposits, whereas coastal systems...... are primarily known from the Cenozoic. The complexity of aeolian sedimentary processes and facies variability are under-represented and excessively simplified in current facies models, which are not sufficiently refined to reliably account for the complexity inherent in bedform morphology and migratory...... behaviour, and therefore cannot be used to consistently account for and predict the nature of the preserved sedimentary record in terms of formative processes. Archean and Neoproterozoic aeolian successions remain poorly constrained. Palaeozoic ergs developed and accumulated in relation...

  19. Quantitative Analogue Experimental Sequence Stratigraphy : Modelling landscape evolution and sequence stratigraphy of river-shelf sedimentary systems by quantitative analogue experiments

    NARCIS (Netherlands)

    Heijst, Maximiliaan Wilhelmus Ignatius Maria van


    This thesis reports a series of flume tank experiments that were conducted to model the stratigraphic evolution of river-delta systems. Chapter 1 introduces the river-delta sedimentary system that is subject of modelling. The chapter also includes an overview of previous research and the summary and

  20. Alteration of Sedimentary Clasts in Martian Meteorite Northwest Africa 7034 (United States)

    McCubbin, F. M.; Tartese, R.; Santos, A. R.; Domokos, G.; Muttik, N.; Szabo, T.; Vazquez, J.; Boyce, J. W.; Keller, L. P.; Jerolmack, D. J.; Anand, M.; Moser, D. E.; Delhaye, T.; Shearer, C. K.; Agee, C. B.


    The martian meteorite Northwest Africa (NWA) 7034 and pairings represent the first brecciated hand sample available for study from the martian surface [1]. Detailed investigations of NWA 7034 have revealed substantial lithologic diversity among the clasts [2-3], making NWA 7034 a polymict breccia. NWA 7034 consists of igneous clasts, impact-melt clasts, and "sedimentary" clasts represented by prior generations of brecciated material. In the present study we conduct a detailed textural and geochemical analysis of the sedimentary clasts.

  1. Geophysical methods for the study of sedimentary cycles

    Institute of Scientific and Technical Information of China (English)

    Xu Jingling; Liu Luofu; Wang Guiwen; Shen Jinsong; Zhang Chunhua


    We present the wavelet depth-frequency analysis and variable-scale frequency cycle analysis methods to study sedimentary cycles. The spectrum analysis, variable-scale frequency cycle analysis, and wavelet depth-frequency analysis methods are mainly discussed to distinguish sedimentary cycles of different levels. The spectrum analysis method established the relationship between the spectrum characteristics and the thickness and number of sedimentary cycles. Both the variable-scale frequency cycle analysis and the wavelet depth-frequency analysis are based on the wavelet transform. The variable-scale frequency cycle analysis is used to obtain the relationship between the periodic changes of frequency in different scales and sedimentary cycles, and the wavelet depth-frequency analysis is used to obtain the relationship between migration changes of frequency energy clusters and sedimentary cycles. We designed a software system to process actual logging data from the Changqing Oilfieid to analyze the sedimentary cycles, which verified the effectiveness of the three methods, and good results were obtained.

  2. Recording of climate and diagenesis through sedimentary DNA and fossil pigments at Laguna Potrok Aike, Argentina (United States)

    Vuillemin, Aurèle; Ariztegui, Daniel; Leavitt, Peter R.; Bunting, Lynda; The Pasado Science Team


    Aquatic sediments record past climatic conditions while providing a wide range of ecological niches for microorganisms. In theory, benthic microbial community composition should depend on environmental features and geochemical conditions of surrounding sediments, as well as ontogeny of the subsurface environment as sediment degraded. In principle, DNA in sediments should be composed of ancient and extant microbial elements persisting at different degrees of preservation, although to date few studies have quantified the relative influence of each factor in regulating final composition of total sedimentary DNA assemblage. Here geomicrobiological and phylogenetic analyses of a Patagonian maar lake were used to indicate that the different sedimentary microbial assemblages derive from specific lacustrine regimes during defined climatic periods. Two climatic intervals (Mid-Holocene, 5 ka BP; Last Glacial Maximum, 25 ka BP) whose sediments harbored active microbial populations were sampled for a comparative environmental study based on fossil pigments and 16S rRNA gene sequences. The genetic assemblage recovered from the Holocene record revealed a microbial community displaying metabolic complementarities that allowed prolonged degradation of organic matter to methane. The series of Archaea identified throughout the Holocene record indicated an age-related stratification of these populations brought on by environmental selection during early diagenesis. These characteristics were associated with sediments resulting from endorheic lake conditions and stable pelagic regime, high evaporative stress and concomitant high algal productivity. In contrast, sulphate-reducing bacteria and lithotrophic Archaea were predominant in sediments dated from the Last Glacial Maximum, in which pelagic clays alternated with fine volcanic material characteristic of a lake level highstand and freshwater conditions, but reduced water column productivity. Comparison of sedimentary DNA composition

  3. Exposures series


    Stimson, Blake


    Reaktion Books’ Exposures series, edited by Peter Hamilton and Mark Haworth-Booth, is comprised of 13 volumes and counting, each less than 200 pages with 80 high-quality illustrations in color and black and white. Currently available titles include Photography and Australia, Photography and Spirit, Photography and Cinema, Photography and Literature, Photography and Flight, Photography and Egypt, Photography and Science, Photography and Africa, Photography and Italy, Photography and the USA, P...


    Energy Technology Data Exchange (ETDEWEB)

    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


    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

  5. Folding and faulting of strain-hardening sedimentary rocks (United States)

    Johnson, A.M.


    The question of whether single- or multi-layers of sedimentary rocks will fault or fold when subjected to layer-parallel shortening is investigated by means of the theory of elastic-plastic, strain-hardening materials, which should closely describe the properties of sedimentary rocks at high levels in the Earth's crust. The most attractive feature of the theory is that folding and faulting, intimately related in nature, are different responses of the same idealized material to different conditions. When single-layers of sedimentary rock behave much as strain-hardening materials they are unlikely to fold, rather they tend to fault, because contrasts in elasticity and strength properties of sedimentary rocks are low. Amplifications of folds in such materials are negligible whether contacts between layer and media are bonded or free to slip for single layers of dolomite, limestone, sandstone, or siltstone in media of shale. Multilayers of these same rocks fault rather than fold if contacts are bonded, but they fold readily if contacts between layers are frictionless, or have low yield strengths, for example due to high pore-water pressure. Faults may accompany the folds, occurring where compression is increased in cores of folds. Where there is predominant reverse faulting in sedimentary sequences, there probably were few structural units. ?? 1980.

  6. Coastal lagoons and beach ridges as complementary sedimentary archives for the reconstruction of Holocene relative sea-level changes

    DEFF Research Database (Denmark)

    Sander, Lasse; Hede, Mikkel Ulfeldt; Fruergaard, Mikkel


    , Denmark. The reconstruction of the initial mid-Holocene sea-level rise is based on the sedimentary infill from topography-confined coastal lagoons (Sander et al., Boreas, 2015b). Sea-level index points over the mid- to late Holocene period of sea-level stability and fall are retrieved from the internal......Coastal lagoons and beach ridges are genetically independent, though non-continuous, sedimentary archives. We here combine the results from two recently published studies in order to produce an 8000-year-long record of Holocene relative sea-level changes on the island of Samsø, southern Kattegat...... proximate occurrence of coastal lagoons and beach ridges allows us to produce seamless time series of relative sea-level changes from field sites in SW Scandinavia and in similar coastal environments....

  7. Applications of Natural Radiation-Induced Paramagnetic Defects in Quartz to Exploration in Sedimentary Basins

    Institute of Scientific and Technical Information of China (English)

    Pan Y M; Botis S; Nokhrin S


    Quartz grains in contact with uranium-bearing minerals or fluids are characterized by natural radiation-induced paramagnetic defects (e. G. , oxygen vacancy centers, silicon vacancy centers, and peroxy radicals), which are amenable to study by electron paramagnetic resonance (EPR) spectroscopy.These natural radiation-induced paramagnetic defects, except for the oxygen vacancy centers, in quartz are concentrated in narrow bands penetrated by α particles: (1) in halos around U- and Th-bearing mineral inclusions and (2) in outer rims or along fractures. The second type of occurrence provides information about uranium mineralization or remobilization (I. E. , sources of uranium, timing of mineralization or remobilization, pathways of uranium-bearing fluids). It can also be used to evaluate sedimentary basins for potential of uranium mineralization. In particular, the peroxy radicals are stable up to 800℃and, therefore, are useful for evaluating metasedimentary rocks (e. G. , Paleoproterozoic metasedimentary sequences in the central zone of the North China craton). EPR study of the Changcheng Series can focus on quartz from the sediment-basement unconformity and faults to determine the presence and types of natural radiation-induced paramagnetic defects, with which to identify and prioritize uranium anomalies. Other potential applications of natural radiation-induced paramagnetic defects in quartz include uranium-bearing hydrocarbon deposits in sedimentary basins. For example, the Junggar, Ordos, and Tarim basins in northwestern China all contain important oil and natural gas fields and are well known for elevated uranium concentrations, including economic sandstone-hosted uranium deposits. Therefore,systematic studies on the distribution of natural radiation-induced paramagnetic defects in quartz from host sedimentary sequences are expected to provide information about the migration of oil and natural gas in those basins.

  8. Building a Bridge to Deep Time: Sedimentary Systems Across Timescales (United States)

    Romans, B.; Castelltort, S.; Covault, J. A.; Walsh, J. P.


    It is increasingly important to understand the complex and interdependent processes associated with sediment production, transport, and deposition at timescales relevant to civilization (annual to millennial). However, predicting the response of sedimentary systems to global environmental change across a range of timescales remains a significant challenge. For example, a significant increase in global average temperature at the Paleocene-Eocene boundary (55.8 Ma) is interpreted to have occurred over millennial timescales; however, the specific response of sedimentary systems (e.g., timing and magnitude of sediment flux variability in river systems) to that forcing is debated. Thus, using such environmental perturbations recorded in sedimentary archives as analogs for ongoing/future global change requires improved approaches to bridging across time. Additionally, the ability to bridge timescales is critical for addressing other questions about sedimentary system behavior, including signal propagation and signal versus ';noise' in the record. The geologic record provides information that can be used to develop a comprehensive understanding of process-response behavior at multiple timescales. The geomorphic ';snapshot' of present-day erosional and depositional landscapes can be examined to reconstruct the history of processes that created the observable configurations. Direct measurement and monitoring of active processes are used to constrain conceptual and numerical models and develop sedimentary system theory. But real-time observations of active Earth-surface processes are limited to the very recent, and how such processes integrate over longer timescales to transform into strata remains unknown. At longer timescales (>106 yr), the stratigraphic record is the only vestige of ancient sedimentary systems. Stratigraphic successions contain a complex record of sediment deposition and preservation, as well as the detrital material that originated in long since denuded

  9. Prediction of thermal conductivity of sedimentary rocks from well logs

    DEFF Research Database (Denmark)

    Fuchs, Sven; Förster, Andrea


    . A common procedure in the latter approach is the use of empirical relations between TC and different petrophysical properties. Although numerous prediction equations were developed in the past five decades, none of these seem to be universally applicable for all major types of sedimentary rocks (clastics...... parameters (i.e. thermal conductivity, density, hydrogen index, sonic interval transit time, gamma-ray response, photoelectric factor) of artificial mineral assemblages consisting 15 rock-forming minerals that are used in different combinations to typify sedimentary rocks. The predictive capacity of the new...

  10. Diagenesis of sedimentary phosphorite deposits in Djebel Onk basin, Algeria

    DEFF Research Database (Denmark)

    Redjehimi, Hacène; Friis, Henrik; Boutaleb, Abdelhak

    Phosphate rocks are important economic natural resources. The sedimentary succession of Djebel Onk, which is characterised by the deposition of phosphatic formations of Late Palaeocene - Early Eocene age (Upper Thanetian-Lower Ypresian), range in age from Upper Cretaceous (Maastrichtian) to the E......Phosphate rocks are important economic natural resources. The sedimentary succession of Djebel Onk, which is characterised by the deposition of phosphatic formations of Late Palaeocene - Early Eocene age (Upper Thanetian-Lower Ypresian), range in age from Upper Cretaceous (Maastrichtian...

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

    Energy Technology Data Exchange (ETDEWEB)

    Goso, C.; Santa Ana, H. de (Administracion Nacional de Combustibles, Alcohol y Portland (Uruguay))


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

  12. Natural Radioactivity Measurements and Radiation Dose Estimation in Some Sedimentary Rock Samples in Turkey

    Directory of Open Access Journals (Sweden)

    I. Akkurt


    Full Text Available The natural radioactivity existed since creation of the universe due to the long life time of some radionuclides. This natural radioactivity is caused by γ-radiation originating from the uranium and thorium series and 40K. In this study, the gamma radiation has been measured to determine natural radioactivity of 238U, 232Th, and 40K in collected sedimentary rock samples in different places of Turkey. The measurements have been performed using γ-ray spectrometer containing NaI(Tl detector and multichannel analyser (MCA. Absorbed dose rate (D, annual effective dose (AED, radium equivalent activities (Raeq, external hazard index (Hex, and internal hazard index (Hin associated with the natural radionuclide were calculated to assess the radiation hazard of the natural radioactivity in the sedimentary rock samples. The average values of absorbed dose rate in air (D, annual effective dose (AED, radium equivalent activity (Raeq, external hazard index (Hex, and internal hazard index (Hin were calculated and these were 45.425 nGy/h, 0.056 mSv/y, 99.014 Bq/kg, 0.267, and 0.361, respectively.

  13. High resolution model studies of transport of sedimentary material in the south-western Baltic (United States)

    Seifert, Torsten; Fennel, Wolfgang; Kuhrts, Christiane


    The paper presents high resolution model simulations of transport, deposition and resuspension of sedimentary material in the south-western Baltic, based on an upgrade of the sediment transport model described in the work of Kuhrts et al. [Kuhrts, C., Fennel, W., Seifert, T., 2004. Model studies of transport of sedimentary material in the Western Baltic. Journal of Marine Systems 52, 167.]. In the western Baltic, a grid spacing of at least 1 nautical mile is required to resolve the shallow and narrow bathymetry and the associated current patterns. A series of experimental model simulations is carried out with forcing data for the year 1993, which include a sequence of storms in January. Compared to earlier model versions, a more detailed description of potential deposition areas can be provided. The study quantifies the influence of enhanced bottom roughness caused by biological structures, like mussels and worm holes, provides estimates of the regional erosion risks for fine grained sediments, and analyses scenarios of the settling and spreading of material at dumping sites. Although the effects of changed bottom roughness, as derived from more detailed, re-classified sea floor data, are relatively small, the sediment transport and deposition patterns are clearly affected by the variation of the sea bed properties.

  14. The Behaviour of Fracture Growth in Sedimentary Rocks: A Numerical Study Based on Hydraulic Fracturing Processes

    Directory of Open Access Journals (Sweden)

    Lianchong Li


    Full Text Available To capture the hydraulic fractures in heterogeneous and layered rocks, a numerical code that can consider the coupled effects of fluid flow, damage, and stress field in rocks is presented. Based on the characteristics of a typical thin and inter-bedded sedimentary reservoir, China, a series of simulations on the hydraulic fracturing are performed. In the simulations, three points, i.e., (1 confining stresses, representing the effect of in situ stresses, (2 strength of the interfaces, and (3 material properties of the layers on either side of the interface, are crucial in fracturing across interfaces between two adjacent rock layers. Numerical results show that the hydrofracture propagation within a layered sequence of sedimentary rocks is controlled by changing in situ stresses, interface properties, and lithologies. The path of the hydraulic fracture is characterized by numerous deflections, branchings, and terminations. Four types of potential interaction, i.e., penetration, arrest, T-shaped branching, and offset, between a hydrofracture and an interface within the layered rocks are formed. Discontinuous composite fracture segments resulting from out-of-plane growth of fractures provide a less permeable path for fluids, gas, and oil than a continuous planar composite fracture, which are one of the sources of the high treating pressures and reduced fracture volume.

  15. Identification of thick sedimentary plains north of Hellas (United States)

    Salese, Francesco; Mangold, Nicolas; Ansan, Veronique; Carter, John; Ody, Anouck; Poulet, François; Ori, Gian Gabriele


    Understanding the origin and timing of intercrater plains is crucial to understand the Martian history in relation with endogenic and/or exogenic cycles. Intercrater plains north of Hellas basin on Mars are thought to have hosted different sedimentary environments during the Late Noachian/Early Hesperian, and they offer a well-preserved insight into the regional geological history of Mars. Our new geologic mapping of the intercrater plains north of Hellas Basin is based on the rich data set from MRO and Mars Express and provides new insights into the region's geological history. These findings appear to constrain the interpretation of the nature and age of intercrater plains in this region, although we acknowledge that for example the source of the sedimentary deposits must be subject to further analysis. The northern part of Hellas basin displays topographically flat area, which was characterized during the Late Noachian by sedimentary deposition and later, in the Late Hesperian, by fissural volcanism. The map and crater retention ages enable us to interpret the geologic history of the region. The stratigraphically lower unit is represented by crustal outcrops. Across most of the region, the sedimentary unit covers the basement and is eroded into mesas, erosional windows and perched by fresh craters. Intercrater plains' sedimentary deposits north of Hellas display horizontal light-toned layered rich in Fe/Mg-phyllosilicates and local crossbedding stratification. The Noachian sedimentary deposits of the intercrater plains north of Hellas are locally covered by Hesperian lava flows, showing that intercrater plains are sedimentary and volcanic in origin. We found different erosional (regional and local) surfaces, at HiRISE scale inside sediments due to local erosional windows and at CTX scale we found two important regional erosional surfaces. The oldest between crustal outcrops and sediments, which is likely Middle Noachian in age and the youngest between sediments


    Directory of Open Access Journals (Sweden)

    I. A. Larionov


    Full Text Available The results of investigations of the deformation process in the near surface sedimentary rocks, which has been carried out in a seismically active region of Kamchatka peninsular since 2007,are presented. The peculiarity of the experiments on the registration of geodeformations is the application of a laser deformograph-interferometer constructed according to the Michelson interferometer scheme.

  17. Stability of IRSL signals from sedimentary K-feldspar samples

    DEFF Research Database (Denmark)

    Thomsen, Kristina Jørkov; Murray, A.S.; Jain, Mayank


    for potassium-rich sedimentary feldspars. We show that the natural post-IR IRSL (pIRIR) signal from a 3.6 Ma old sample is in apparent saturation on a laboratory generated dose response curve, i.e. it does not show detectable fading in nature although a low fading rate is observed on laboratory time scales. We...

  18. Sedimentary exhalative (sedex) zinc-lead-silver deposit model (United States)

    Emsbo, Poul; Seal, Robert R.; Breit, George N.; Diehl, Sharon F.; Shah, Anjana K.


    This report draws on previous syntheses and basic research studies of sedimentary exhalative (sedex) deposits to arrive at the defining criteria, both descriptive and genetic, for sedex-type deposits. Studies of the tectonic, sedimentary, and fluid evolution of modern and ancient sedimentary basins have also been used to select defining criteria. The focus here is on the geologic characteristics of sedex deposit-hosting basins that contain greater than 10 million metric tons of zinc and lead. The enormous size of sedex deposits strongly suggests that basin-scale geologic processes are involved in their formation. It follows that mass balance constraints of basinal processes can provide a conceptual underpinning for the evaluation of potential ore-forming mechanisms and the identification of geologic indicators for ore potential in specific sedimentary basins. Empirical data and a genetic understanding of the physicochemical, geologic, and mass balance conditions required for each of these elements are used to establish a hierarchy of quantifiable geologic criteria that can be used in U.S. Geological Survey national assessments.  In addition, this report also provides a comprehensive evaluation of environmental considerations associated with the mining of sedex deposits.

  19. Evidence for a small bacterial contribution to sedimentary organic carbon

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Hartgers, W.A.; Requejo, A.G.; Allan, J.; Hayes, J.M.; Leeuw, J.W. de


    Because their molecular signatures are often prominent in extracts of sediments, bacteria are thought to be important contributors to petroleum source beds. It has been shown recently, however, that abundances of biomarkers do not always reflect relative contributions to sedimentary organic carbon (

  20. DCP Series

    Directory of Open Access Journals (Sweden)

    Philip Stearns


    Full Text Available Photo essay. A collection of Images produced by intentionally corrupting the circuitry of a Kodak DC280 2 MP digitalcamera. By rewiring the electronics of a digital camera, glitched images are produced in a manner that parallels chemically processing unexposed film or photographic paper to produce photographic images without exposure to light. The DCP Series of Digital Images are direct visualizations of data generated by a digital camera as it takes a picture. Electronic processes associated with the normal operations of the camera, which are usually taken for granted, are revealed through an act of intervention. The camera is turned inside­out through complexes of short­circuits, selected by the artist, transforming the camera from a picture taking device to a data capturing device that renders raw data (electronic signals as images. In essence, these images are snap­shots of electronic signals dancing through the camera's circuits, manually rerouted, written directly to the on­board memory device. Rather than seeing images of the world through a lens, we catch a glimpse of what the camera sees when it is forced to peer inside its own mind.

  1. Sedimentary-volcanic tuffs formed during the early Middle Triassic volcanic event in Guizhou Province and their stratigraphic significance

    Institute of Scientific and Technical Information of China (English)

    XIAO Jiafei; HU Ruizhong


    The sedimentary-volcanic tuff (locally called "green-bean rock") formed during the early Middle Triassic volcanic event in Guizhou Province is characterized as being thin, stable, widespread, short in forming time and predominantly green in color. The green-bean rock is a perfect indicator for stratigraphic division. Its petrographic and geochemical features are unique, and it is composed mainly of glassy fragments and subordinately of crystal fragments and volcanic ash balls. Analysis of the major and trace elements and rare-earth elements (REE), as well as the related diagrams, permits us to believe that the green-bean rock is acidic volcanic material of the calc-alkaline series formed in the Indosinian orogenic belt on the Sino-Vietnam border, which was atmospherically transported to the tectonically stable areas and then deposited as sedimentary-volcanic rocks there. According to the age of green-bean rock, it is deduced that the boundary age of the Middle-Lower Triassic overlain by the sedimentary-volcanic tuff is about 247 Ma.

  2. Sedimentary responses to sub-aerial felsic volcanism from the Late Devonian-Early Carboniferous northern Macalister Synclinorium, southeastern Australia (United States)

    O'Halloran, G. J.; Gaul, A. J.


    Active sub-aerial volcanism has the capability to rapidly alter both the topographic and drainage characteristics of a landscape, and thus fundamentally influence resulting sedimentary facies. Relationships between sedimentation and volcanism are explored in this paper, via an investigation of the stratigraphy and early depositional history of the Upper Devonian volcano-sedimentary units of the northern Macalister Synclinorium, east-central Victoria. Complex interfingering relationships exist between sub-aerial felsic volcanic successions (Rose River Volcanics) and alluvial, fluvial and lacustrine sedimentary units (the Bindaree and Howitt Spur Formations). A depositional model is presented for these units, in which the Rose River Volcanics, an outflow (ignimbritic plateau) facies of the Tolmie caldera complex to the north, co-existed with a series of volcaniclastic alluvial fans and freshwater lakes. A dacitic volcanic centre (Refrigerator Gap Dacite) appears to have developed somewhat separately to the south, in the Jamieson River area. These lower successions of the northern Macalister Synclinorium record an episode of sedimentation in close proximity to an active felsic volcanic terrain, and in a landscape of significant topographic relief. The conglomerates of the Bindaree Formation, in particular, record the supply of abundant felsic volcanic detritus via high-gradient proximal alluvial stream systems. Comparisons can be made with sedimentological processes operating during deposition of overlying sedimentary successions, where influences by primary volcanic activity were less important. Well defined channel geometry successions and a diversification in clast and grain types within these younger units indicate ongoing headward erosion into metasedimentary basement rocks, and deposition within lower-gradient, higher-order stream systems.

  3. Sedimentary Petrology: from Sorby to the globalization of Sedimentary Geology; La Petrologia Sedimentaria: desde Sorby a la globalizacion de la Geologia Sedimentaria

    Energy Technology Data Exchange (ETDEWEB)

    Alonso-Zarza, A. M.


    We describe here the most important milestones and contributions to Sedimentary Petrology compared to other geological disciplines. We define the main aim of our study and the scientific and economic interests involved in Sedimentary Petrology. The body of the paper focuses upon the historical development of this discipline from Henry Sorby's initial work until the present day. The major milestones in its history include: 1) initial descriptive works; 2) experimental studies; 3) the establishment of the different classifications of sedimentary rocks; 4) studies into facies and sedimentary environments; 5) advances in the study of diagenetic processes and their role in hydrocarbon prospection; and 6) the development of Sedimentary Geochemistry. Relationships and coincidences with Sedimentology are discussed. We go on to look at the advances that have taken place over the last 30 years, in which the study of sedimentary rocks is necessarily included in the wider field of Sedimentary Geology as a logical result of the proposal of global models of a changing Earth in which Sedimentary Geology plays a significant part. Finally we mention the notable contributions of Spanish sedimentary petrologists to this whole field of science. (Author) 120 refs.

  4. Organic sedimentary deposits in Titan's dry lakebeds: Probable evaporite (United States)

    Barnes, J.W.; Bow, J.; Schwartz, J.; Brown, R.H.; Soderblom, J.M.; Hayes, A.G.; Vixie, G.; Le, Mouelic S.; Rodriguez, S.; Sotin, C.; Jaumann, R.; Stephan, K.; Soderblom, L.A.; Clark, R.N.; Buratti, B.J.; Baines, K.H.; Nicholson, P.D.


    We report the discovery of organic sedimentary deposits at the bottom of dry lakebeds near Titan's north pole in observations from the Cassini Visual and Infrared Mapping Spectrometer (VIMS). We show evidence that the deposits are evaporitic, making Titan just the third known planetary body with evaporitic processes after Earth and Mars, and is the first that uses a solvent other than water. ?? 2011 Elsevier Inc.

  5. Preliminary catalog of the sedimentary basins of the United States (United States)

    Coleman, James L.; Cahan, Steven M.


    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.

  6. Favorability for uranium in tertiary sedimentary rocks, southwestern Montana

    Energy Technology Data Exchange (ETDEWEB)

    Wopat, M A; Curry, W E; Robins, J W; Marjaniemi, D K


    Tertiary sedimentary rocks in the basins of southwestern Montana were studied to determine their favorability for potential uranium resources. Uranium in the Tertiary sedimentary rocks was probably derived from the Boulder batholith and from silicic volcanic material. The batholith contains numerous uranium occurrences and is the most favorable plutonic source for uranium in the study area. Subjective favorability categories of good, moderate, and poor, based on the number and type of favorable criteria present, were used to classify the rock sequences studied. Rocks judged to have good favorability for uranium deposits are (1) Eocene and Oligocene strata and undifferentiated Tertiary rocks in the western Three Forks basin and (2) Oligocene rocks in the Helena basin. Rocks having moderate favorability consist of (1) Eocene and Oligocene strata in the Jefferson River, Beaverhead River, and lower Ruby River basins, (2) Oligocene rocks in the Townsend and Clarkston basins, (3) Miocene and Pliocene rocks in the Upper Ruby River basin, and (4) all Tertiary sedimentary formations in the eastern Three Forks basin, and in the Grasshopper Creek, Horse Prairie, Medicine Lodge Creek, Big Sheep Creek, Deer Lodge, Big Hole River, and Bull Creek basins. The following have poor favorability: (1) the Beaverhead Conglomerate in the Red Rock and Centennial basins, (2) Eocene and Oligocene rocks in the Upper Ruby River basin, (3) Miocene and Pliocene rocks in the Townsend, Clarkston, Smith River, and Divide Creek basins, (4) Miocene through Pleistocene rocks in the Jefferson River, Beaverhead River, and Lower Ruby River basins, and (5) all Tertiary sedimentary rocks in the Boulder River, Sage Creek, Muddy Creek, Madison River, Flint Creek, Gold Creek, and Bitterroot basins.

  7. Analysis of the Behavior of Sedimentary Rocks Under Impact Loading (United States)

    Millon, Oliver; Ruiz-Ripoll, Maria Luisa; Hoerth, Tobias


    In multiple engineering fields such as rock drilling or building constructions or extreme events like earthquakes or impacts, the dynamic properties of rock play an important role. A way to model these events and define measures to minimize the damage derived from these events is created by means of numerical analysis. Hence, the knowledge of the dynamic material behavior is essential for studying the effects of such a loading scenario. Solid geological materials, from the family of the sedimentary rocks, have been analyzed under quasi-static loads. However, there is a lack of knowledge when high strain rate loadings are involved. Within this context, the paper focuses on the experimental characterization of two sedimentary rocks, sandstone and limestone, under impact loading using the Hopkinson-Bar spallation and compression tests. The analysis encompasses the determination of the tensile and compressive properties as well as the comparison between the quasi-static and dynamic behavior (dynamic increase factors). The paper fills the gap of information existing about dynamic behavior of sedimentary rocks under strain rates between 100 and 5.2 × 102 s-1. Furthermore, the fragmentation under different strain rates is investigated and conclusions with respect to energy absorption capacity are drawn.

  8. Decoupled sedimentary records of combustion: Causes and implications (United States)

    Hanke, Ulrich M.; Eglinton, Timothy I.; Braun, Ana L. L.; Reddy, Christopher M.; Wiedemeier, Daniel B.; Schmidt, Michael W. I.


    Pyrogenic carbon (PyC) is a collective term for carbon-rich residues comprised of a continuum of products arising from biomass burning and fossil-fuel combustion. PyC is ubiquitous in the environment where it can be transported by wind and water before being deposited in aquatic sediments. We compare results from four different methods used to trace PyC that were applied to a high-temporal resolution sedimentary record in order to constrain changes in PyC concentrations and fluxes over the past ~250 years. We find markedly discordant records for different PyC tracers, particularly during the preindustrial age, implying different origins and modes of supply of sedimentary PyC. In addition to providing new insights into the composition of sedimentary combustion products, this study reveals that elucidation of past combustion processes and development of accurate budgets of PyC production and deposition on local to regional scales requires careful consideration of both source characteristics and transport processes.

  9. DOE workshop: Sedimentary systems, aqueous and organic geochemistry

    Energy Technology Data Exchange (ETDEWEB)


    A DOE workshop on sedimentary systems, aqueous and organic geochemistry was held July 15-16, 1993 at Lawrence Berkeley Laboratory. Papers were organized into several sections: Fundamental Properties, containing papers on the thermodynamics of brines, minerals and aqueous electrolyte solutions; Geochemical Transport, covering 3-D imaging of drill core samples, hydrothermal geochemistry, chemical interactions in hydrocarbon reservoirs, fluid flow model application, among others; Rock-Water Interactions, with presentations on stable isotope systematics of fluid/rock interaction, fluid flow and petotectonic evolution, grain boundary transport, sulfur incorporation, tracers in geologic reservoirs, geothermal controls on oil-reservoir evolution, and mineral hydrolysis kinetics; Organic Geochemistry covered new methods for constraining time of hydrocarbon migration, kinetic models of petroleum formation, mudstones in burial diagenesis, compound-specific carbon isotope analysis of petroleums, stability of natural gas, sulfur in sedimentary organic matter, organic geochemistry of deep ocean sediments, direct speciation of metal by optical spectroscopies; and lastly, Sedimentary Systems, covering sequence stratigraphy, seismic reflectors and diagenetic changes in carbonates, geochemistry and origin of regional dolomites, and evidence of large comet or asteroid impacts at extinction boundaries.

  10. Sequence associations of sedimentary facies in continental basins and their applications to palaeogeographic mapping

    Institute of Scientific and Technical Information of China (English)

    TANG Hua-feng; CHENG Ri-hui; KONG Qing-ying; BAI Yun-feng; YU Ming-feng


    According to the characteristics of sedimentary facies and their vertical associations, sequence association of sedimentary facies can be divided into 2 types and 28 subtypes. The first type (type A) is a sedimentary sequence without volcanic rocks, including 18 subtypes. The second type (type B) is a volcanogenic succession including 10 subtypes.Each subtype may reflect certain filling condition under certain sedimentary environment. Time and space distribution of different types of sequence associations can reflect tectonics that controlled the basin evolution, sedimentary environments and palaeogeography.

  11. Processing of thermal parameters for the assessment of geothermal potential of sedimentary basins (United States)

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


    having two or more temperature measurements at a single depth we selected 18 wells with BHTs recorded at te larger than 3.5 hours; the time span between two measurements varies from 1 to 21 hours. In total 71 couples of BHT-te data are available; the mud circulation time is lower or equal to 4.5 hours. Corrections require the knowledge of thermal parameters. We attempted to remedy the existing deficiency of thermal conductivity data of sedimentary rocks with a series of laboratory measurements on several core samples recovered from wells. Moreover, we developed a model for calculating the thermal conductivity of the rock matrix as a function of mineral composition based on the fabric theory and experimental thermal conductivity data. As the conductivity of clay minerals, which are present in most formations, is poorly defined, we applied an inverse approach, in which mineral conductivities are calculated one by one, on condition that the sample bulk thermal conductivity, the porosity and the amount of each mineral phase are known. Analyses show that formation equilibrium temperatures computed with the Horner method are consistent with those obtained by means of the Cooper and Jones method, which gives on average temperatures lower than 2 C only for shut-in times geothermal gradient is 21.5 mK/m in the Apenninic buried arc area and 25.2 mK/m in the South Piedmont Basin-Pedealpine homocline area. The problem with the Horner method is that it implicitly assumes no physical property contrast between circulating mud and formation, and that the borehole is infinitesimally thin, i.e. it acts as a line source. This has been criticized by many authors. The accuracy of the predicted temperatures depends on the reliability and accuracy of BHT, shut-in time and mud circulation time, and the error increases with the decrease of the shut-in time. On the ot

  12. Chlorine isotope behavior during prograde metamorphism of sedimentary rocks (United States)

    Selverstone, Jane; Sharp, Zachary D.


    Chlorine stable isotope compositions of two sedimentary sequences and their metamorphic equivalents were measured in order to study fractionation effects during prograde metamorphism and devolatilization. Protoliths (n = 25) were collected from a 50 m section of Triassic fluvial and playa-lake strata and Jurassic (Liassic) marine black shales in a well-characterized quarry. Low greenschist to middle amphibolite facies equivalents (n > 80) were collected from the Glarus Alps, Urseren Zone, and Lucomagno region. Bulk δ37Cl values are constant within individual sedimentary layers, but vary from -2.0 to + 2.4 ‰ in Triassic rocks and from -3.0 to 0‰ in the black shales. Dolomitic and gypsiferous samples have positive δ37Cl values, but marls and shales are isotopically negative. Bulk Cl contents show only small declines during the earliest stages of metamorphism. Metamorphic equivalents of the Triassic and Liassic protoliths record the same overall ranges in δ37Cl as their protoliths. Samples with highly correlated bulk compositions but different metamorphic grade show no statistically significant difference in δ37Cl. These data lead to the following conclusions: (1) Terrestrial and marine sedimentary rocks display large primary heterogeneities in chlorine isotope composition. As a result, an unambiguous "sedimentary signature" does not exist in the chlorine stable isotope system. (2) No isotopic fractionation is discernable during metamorphic devolatilization, even at low temperatures. Alpine-style metamorphism thus has little to no effect on bulk chlorine isotopic compositions, despite significant devolatilization. (3) Cl is largely retained in the rocks during devolatilization, contrary to the normally assumed hydrophilic behavior of chlorine. Continuous release of mixed-volatile C-O-H fluids likely affected Cl partitioning between fluid and minerals and allowed chlorine to remain in the rocks. (4) There is no evidence for fluid communication across (meta)sedimentary

  13. Magnetostratigraphy of the middle-upper Jurassic sedimentary sequences at Yanshiping, Qiangtang Basin, China (United States)

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


    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.

  14. In situ NMR analysis of fluids contained in sedimentary rock (United States)

    de Swiet TM; Tomaselli; Hurlimann; Pines


    Limitations of resolution and absorption in standard chemical spectroscopic techniques have made it difficult to study fluids in sedimentary rocks. In this paper, we show that a chemical characterization of pore fluids may be obtained in situ by magic angle spinning (MAS) nuclear magnetic resonance (NMR), which is normally used for solid samples. 1H MAS-NMR spectra of water and crude oil in Berea sandstone show sufficient chemical shift resolution for a straightforward determination of the oil/water ratio. Copyright 1998 Academic Press.

  15. Mineral composition of sedimentary matter in the Caspian Sea (United States)

    Lukashin, V. N.; Lisitzin, A. P.; Dara, O. M.; Kozina, N. V.; Klyuvitkin, A. A.; Novigatsky, A. N.


    Data on the mineral composition of sedimentary matter and its fluxes in the sediment system of the Caspian Sea are presented. River runoff, aerosols, particulate matter from sediment traps, and the upper layer (0-1 cm) of bottom sediments are considered. The contents of detrital minerals (quartz, albite, and K-feldspar), clay minerals (illite, chlorite, and kaolinite), and carbonates (calcite, Mg-calcite, dolomite, aragonite, and rhodochrosite) are determined. Gypsum was found in bottom sediments but is absent in the other object of the sediment system.

  16. The impact of sedimentary coatings on the diagenetic Nd flux (United States)

    Abbott, April N.; Haley, Brian A.; McManus, James


    Because ocean circulation impacts global heat transport, understanding the relationship between deep ocean circulation and climate is important for predicting the ocean's role in climate change. A common approach to reconstruct ocean circulation patterns employs the neodymium isotope compositions of authigenic phases recovered from marine sediments. In this approach, mild chemical extractions of these phases is thought to yield information regarding the εNd of the bottom waters that are in contact with the underlying sediment package. However, recent pore fluid studies present evidence for neodymium cycling within the upper portions of the marine sediment package that drives a significant benthic flux of neodymium to the ocean. This internal sedimentary cycling has the potential to obfuscate any relationship between the neodymium signature recovered from the authigenic coating and the overlying neodymium signature of the seawater. For this manuscript, we present sedimentary leach results from three sites on the Oregon margin in the northeast Pacific Ocean. Our goal is to examine the potential mechanisms controlling the exchange of Nd between the sedimentary package and the overlying water column, as well as the relationship between the εNd composition of authigenic sedimentary coatings and that of the pore fluid. In our comparison of the neodymium concentrations and isotope compositions from the total sediment, sediment leachates, and pore fluid we find that the leachable components account for about half of the total solid-phase Nd, therefore representing a significant reservoir of reactive Nd within the sediment package. Based on these and other data, we propose that sediment diagenesis determines the εNd of the pore fluid, which in turn controls the εNd of the bottom water. Consistent with this notion, despite having 1 to 2 orders of magnitude greater Nd concentration than the bottom water, the pore fluid is still <0.001% of the total Nd reservoir in the

  17. Isolation of Geobacter species from diverse sedimentary environments (United States)

    Coaxes, J.D.; Phillips, E.J.P.; Lonergan, D.J.; Jenter, H.; Lovley, D.R.


    In an attempt to better understand the microorganisms responsible for Fe(III) reduction in sedimentary environments, Fe(III)-reducing microorganisms were enriched for and isolated from freshwater aquatic sediments, a pristine deep aquifer, and a petroleum-contaminated shallow aquifer. Enrichments were initiated with acetate or toluene as the electron donor and Fe(III) as the electron acceptor. Isolations were made with acetate or benzoate. Five new strains which could obtain energy for growth by dissimilatory Fe(III) reduction were isolated. All five isolates are gram- negative strict anaerobes which grow with acetate as the electron donor and Fe(III) as the electron acceptor. Analysis of the 16S rRNA sequence of the isolated organisms demonstrated that they all belonged to the genus Geobacter in the delta subdivision of the Proteobacteria. Unlike the type strain, Geobacter metallireducens, three of the five isolates could use H2 as an electron donor fur Fe(III) reduction. The deep subsurface isolate is the first Fe(III) reducer shown to completely oxidize lactate to carbon dioxide, while one of the freshwater sediment isolates is only the second Fe(III) reducer known that can oxidize toluene. The isolation of these organisms demonstrates that Geobacter species are widely distributed in a diversity of sedimentary environments in which Fe(III) reduction is an important process.

  18. Bottom-trawling along submarine canyons impacts deep sedimentary regimes (United States)

    Paradis, Sarah; Puig, Pere; Masqué, Pere; Juan-Díaz, Xènia; Martín, Jacobo; Palanques, Albert


    Many studies highlight that fish trawling activities cause seafloor erosion, but the assessment of the remobilization of surface sediments and its relocation is still not well documented. These impacts were examined along the flanks and axes of three headless submarine canyons incised on the Barcelona continental margin, where trawling fleets have been operating for decades. Trawled grounds along canyon flanks presented eroded and highly reworked surface sediments resulting from the passage of heavy trawling gear. Sedimentation rates on the upper canyon axes tripled and quadrupled its natural (i.e. pre-industrialization) values after a substantial increase in total horsepower of the operating trawling fleets between 1960 s and 1970 s. These impacts affected the upper canyon reaches next to fishing grounds, where sediment resuspended by trawling can be transported towards the canyon axes. This study highlights that bottom trawling has the capacity to alter natural sedimentary environments by promoting sediment-starved canyon flanks, and by enhancing sedimentation rates along the contiguous axes, independently of canyons’ morphology. Considering the global mechanisation and offshore expansion of bottom trawling fisheries since the mid-20th century, these sedimentary alterations may occur in many trawled canyons worldwide, with further ecological impacts on the trophic status of these non-resilient benthic communities. PMID:28233856

  19. Phanerozoic Sedimentary Corg:P Ratios and Paleocean Ventilation (United States)

    Algeo, T. J.


    Phosphorus is probably the major limiting nutrient on marine primary productivity at geological timescales, although other elements (e.g., N, Fe) can be transiently biolimiting. It has been inferred that remineralization of organic P and upwelling of nutrient-rich deepwaters have the potential to stimulate primary productivity, and that measurements of sedimentary (C:P)org ratios in ancient sediments can yield insights on nutrient fluxes and productivity levels in paleoceans. However, recent work has shown that (1) sedimentary (C:P)org ratios exceed the Redfield ratio (106:1) in most environments as a result of preferential bacterial destruction of labile P-bearing compounds, and (2) the inorganic P fractions associated with Fe-bound and authigenic phosphate phases in anoxic sediments are largely of organic derivation, representing remineralized P that has been fixed through redox-related processes. These insights suggest that the most useful measure of nutrient regeneration is the nondetrital P fraction of sediments, a variable that is rarely determined but that can be adequately proxied by total P in anoxic facies, in which the detrital P fraction is typically small. In this study, Corg:P ratios were determined for 60 anoxic facies of Cambrian through Recent age. The Recent facies yield a mean Corg:P of 65±25, values similar to those for most anoxic facies of Mississippian and younger age. In contrast, many Cambrian-Devonian anoxic facies yield substantially higher Corg:P ratios, with the highest values (>400) in the Middle-Upper Cambrian and Middle-Upper Devonian. For the Phanerozoic as a whole, the logarithmic mean Corg:P ratio declines by a factor of four, from ~260:1 in the Cambrian to 65:1 in the Recent, a statistically robust result. Given the importance of redox controls on sedimentary P retention at a local scale, this pattern can be interpreted as a record of benthic redox conditions through time, i.e., paleocean ventilation. Although Recent anoxic

  20. Summation of series

    CERN Document Server

    Jolley, LB W


    Over 1,100 common series, all grouped for easy reference. Arranged by category, these series include arithmetical and geometrical progressions, powers and products of natural numbers, figurate and polygonal numbers, inverse natural numbers, exponential and logarithmic series, binomials, simple inverse products, factorials, trigonometrical and hyperbolic expansions, and additional series. 1961 edition.

  1. {sup 210}Pb dating of sediments from the central and the northern Adriatic Sea: The deposition and preservation of sedimentary organic carbon

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, T.; Fowler, S.; Miquel, J.C.; La Rosa, J.


    A central goal of the ELNA project is to assess the carbon assimilation capacity of the Northern Adriatic Sea. This requires fundamental quantitative information on budgets and sinks of organic carbon. Any change in carbon production in the water column should be reflected in the underlying sediments. Moreover, the fraction of particulate organic carbon reaching the sea floor which is subsequently preserved in the sediment will be strongly coupled to sediment accumulation and mixing. In this study a series of box cores were collected in order to characterize a hypothetical eutrophication gradient extending from the Po River outflow region in the north down to the shallow meso-Adriatic depression (Jabuka Pit). The main tasks assigned to IAEA-MEL were to provide {sup 210}Pb derived sedimentation and dry-mass accumulation rates and to examine the possible correlations between sedimentary processes, the deposition and preservation of sedimentary organic carbon and pelagic primary productivity.

  2. Geochemistry of dispersed sedimentary matter and its fluxes in the water column of the Caspian Sea (United States)

    Lukashin, V. N.; Lisitzin, A. P.


    The first data on the chemical composition of dispersed matter from sedimentary traps are reported. The suspended components of sedimentary matter (amorphous silica, organic matter, carbonates, and lithogenic material, as well as Fe, Mn, and minor elements) are considered. As a result, it is shown that the intraannual variability in vertical fluxes of sedimentary matter is characterized by a seasonal increase in spring and autumn. The high fluxes of the components of sedimentary matter on the northern and southern slopes of the Derbent Basin in winter are explained by precipitation of material from the nepheloid layer that forms over the contour current.

  3. Sedimentary dynamics along the west coast of Bohai Bay, China, during the twentieth century

    DEFF Research Database (Denmark)

    Wang, Fu; Wang, Huang; Zong, Y.


    from the sediment cores, the chronology of the sediment sequences was established, from which the sedimentary history of the tidal flats was reconstructed. Results inform spatial and temporal variations in sedimentation rate along the Tianjin coast, from which sedimentary dynamics can be deduced. Two...... in this study. This study highlights the usefulness of applying both 210Pb and 137Cs dating methods. These dating methods, together with detailed sedimentary analysis, can provide valuable sedimentary evidence of coastal change and natural and human causes of change....

  4. Series editorial: Network and Service Management Series

    NARCIS (Netherlands)

    Pavlou, George; Pras, Aiko


    This is the ninth issue of the series on Network and Service Management, which is typically published twice a year. It was originally published in April and October, but since last year it is published in July and December. The series provides articles on the latest developments in this well establi

  5. Series editorial: Network and Service Management Series

    NARCIS (Netherlands)

    Pavlou, George; Pras, Aiko


    This is the 11th issue of the series on Network and Service Management, which is typically published twice a year. It was originally published in April and October but since last year it is published in July and December. The series provides articles on the latest developments in this well-establish

  6. Hydrogeologic framework of fractured sedimentary rock, Newark Basin, New Jersey (United States)

    Lacombe, Pierre J.; Burton, William C.


    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

  7. Hydraulic jumps within pyroclastic density currents and their sedimentary record (United States)

    Douillet, G.; Mueller, S.; Kueppers, U.; Dingwell, D. B.


    This contribution presents a complete and comprehensive formulation of the hydraulic jump phenomenon and reviews sedimentary structures that may be associated with them. Beginning from the general fluid phenomenon, we then focus on examples from pyroclastic density currents in order to infer dynamic parameters on the parent flows. A hydraulic jump is a fluid dynamics phenomenon that corresponds to the sudden increase of the thickness of a flow accompanied by a decrease of its velocity and/or density. A hydraulic jump is the expression of the transition of the flow from two different flow regimes: supercritical to subcritical. This entrains a change in the energy balance between kinetic energy and gravity potential energy. Recently, the terms of 'pneumatic jumps' have been used for similar phenomenon driven within a gas phase, and granular jumps for dense granular flows. It is thought that such strong changes in the flow conditions may leave characteristic structures in the sedimentary record. Indeed, the main variables influencing the sedimentation rate are the flow velocity, particle concentration and turbulence level, all of them strongly affected by a hydraulic jump. Structures deposited by hydraulic/pneumatic jumps have been called cyclic steps and chute and pool structures. Chute and pools represent the record of a single supercritical to subcritical transition, whereas cyclic steps are produced by stable trains of hydraulic jumps and subsequent re-accelerations. Pyroclastic density currents (PDCs) are gas and pyroclasts flows. As such, they can be subjected to granular and pneumatic jumps and their deposit have often been interpreted as containing records of jumps. Steep sided truncations covered by lensoidal layers have been interpreted as the record of internal jumps within density stratified flows. Fines-depleted breccias at breaks in slope are thought to result from the enhanced turbulence at a jump of the entire flow. Sudden increases in thickness of

  8. Test of hyperelasticity in highly nonlinear solids: sedimentary rocks. (United States)

    D'Angelo, R M; Winkler, K W; Plona, T J; Landsberger, B J; Johnson, D L


    We report measurements of three-wave mixing amplitudes on systems whose third order elastic constants have also been measured by means of the elastoacoustic effect. Because attenuation and diffraction are an important aspect of our measurement technique we analyze our results using a modified Khoklhov-Zabolotskaya-Kuznetsov equation in the frequency domain. We find that the value of beta so deduced for polymethyl methacrylate agrees quite well with that predicted from the stress dependent sound speed measurements, establishing that polymethyl methacrylate may be considered as a hyperelastic solid. The beta values of sedimentary rocks, though they are typically 2 orders of magnitude larger than, e.g., polymethyl methacrylates, are still a factor 3-10 less than those predicted from the elastoacoustic effect.

  9. Multilayered aquifer modeling in the coastal sedimentary basin of Togo (United States)

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


    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.

  10. Sources of sedimentary humic substances: vascular plant debris (United States)

    Ertel, John R.; Hedges, John I.


    A modern Washington continental shelf sediment was fractionated densimetrically using either an organic solvent, CBrCl 3, or aqueous ZnCl 2. The resulting low density materials (extraction of fresh and naturally degraded vascular plant materials reveals that significant levels of humic and fulvic acids are obtained using classical extraction techniques. Approximately 1-2% of the carbon from fresh woods and 10-25% from leaves and bark were isolated as humic acids and 2-4 times those levels as fulvic acids. A highly degraded hardwood yielded up to 44% of its carbon as humic and fulvic acids. The humic acids from fresh plants are generally enriched in lignin components relative to carbohydrates and recognizable biochemicals account for up to 50% of the total carbon. Humic and fulvic acids extracted directly from sedimentary plant debris could be responsible for a major fraction of the biochemical component of humic substances.

  11. Paleomagnetic studies on sedimentary Jurassic rocks from southern Bulgaria (United States)

    Kruczyk, J.; Kaḑziałko-Hofmokl, M.; Nozharov, P.; Petkov, N.; Nachev, I.

    Paleomagnetic investigations were performed on Jurassic sediments sampled in the mobile area of Bulgaria comprising Srednogorie, Kreiste and Stranja. The main carriers of magnetic properties of rocks studied are pigmentary haematite and goethite of post-sedimentary origin. The characteristic component of natural remanence (CARM), isolated by means of analysis of demagnetization procedure is secondary, and was acquired after the main tectonic event that took place in this area during the Upper Cretaceous. The CARM directions before tectonic correction are close to the results for Upper Cretaceous magmatic rocks from Srednogorie. The mean CARM direction and the corresponding polar position obtained for the whole region studied are compared with reference data for the Eurasian Platform. The difference between the reference and our data implies anticlockwise rotation of southern Bulgaria relative to Eurasia by ˜ 10-20° and a northward tilt of the region under study by ˜ 10-15° after acquisition of CARM.

  12. Research into surface wave phenomena in sedimentary basins (United States)

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


    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.

  13. A seismic network to investigate the sedimentary hosted hydrothermal Lusi system (United States)

    Javad Fallahi, Mohammad; Mazzini, Adriano; Lupi, Matteo; Obermann, Anne; Karyono, Karyono


    The 29th of May 2006 marked the beginning of the sedimentary hosted hydrothermal Lusi system. During the last 10 years we witnessed numerous alterations of the Lusi system behavior that coincide with the frequent seismic and volcanic activity occurring in the region. In order to monitor the effect that the seismicity and the activity of the volcanic arc have on Lusi, we deployed a ad hoc seismic network. This temporary network consist of 10 broadband and 21 short period stations and is currently operating around the Arjuno-Welirang volcanic complex, along the Watukosek fault system and around Lusi, in the East Java basin since January 2015. We exploit this dataset to investigate surface wave and shear wave velocity structure of the upper-crust beneath the Arjuno-Welirang-Lusi complex in the framework of the Lusi Lab project (ERC grant n° 308126). Rayleigh and Love waves travelling between each station-pair are extracted by cross-correlating long time series of ambient noise data recorded at the stations. Group and phase velocity dispersion curves are obtained by time-frequency analysis of cross-correlation functions, and are tomographically inverted to provide 2D velocity maps corresponding to different sampling depths. 3D shear wave velocity structure is then acquired by inverting the group velocity maps.

  14. Predicting the transport properties of sedimentary rocks from microstructure

    Energy Technology Data Exchange (ETDEWEB)

    Schlueter, Erika M. [Univ. of California, Berkeley, CA (United States)


    Understanding transport properties of sedimentary rocks, including permeability, relative permeability, and electrical conductivity, is of great importance for petroleum engineering, waste isolation, environmental restoration, and other applications. These transport properties axe controlled to a great extent by the pore structure. How pore geometry, topology, and the physics and chemistry of mineral-fluid and fluid-fluid interactions affect the flow of fluids through consolidated/partially consolidated porous media are investigated analytically and experimentally. Hydraulic and electrical conductivity of sedimentary rocks are predicted from the microscopic geometry of the pore space. Cross-sectional areas and perimeters of individual pores are estimated from two-dimensional scanning electron microscope (SEM) photomicrographs of rock sections. Results, using Berea, Boise, Massilon, and Saint-Gilles sandstones show close agreement between the predicted and measured permeabilities. Good to fair agreement is found in the case of electrical conductivity. In particular, good agreement is found for a poorly cemented rock such as Saint-Gilles sandstone, whereas the agreement is not very good for well-cemented rocks. The possible reasons for this are investigated. The surface conductance contribution of clay minerals to the overall electrical conductivity is assessed. The effect of partial hydrocarbon saturation on overall rock conductivity, and on the Archie saturation exponent, is discussed. The region of validity of the well-known Kozeny-Carman permeability formulae for consolidated porous media and their relationship to the microscopic spatial variations of channel dimensions are established. It is found that the permeabilities predicted by the Kozeny-Carman equations are valid within a factor of three of the observed values methods.

  15. Tectonic and sedimentary evolution of the Luna field area, Italy

    Energy Technology Data Exchange (ETDEWEB)

    Roveri, M. (AGIP S.A., Milan (Italy))


    The Luna gas field is located near Crotone (Calabria region, southern Italy) in a shallow-water/onshore area. It was discovered and put into production during the early 1970s. Up to now it has produced 19 {times} 10{sup 9} sm{sup 3} of gas; its productivity (50 {times} 10{sup 6} sm{sup 3}/y) has remained virtually unaltered since the beginning. The field is located on the axial culmination of a thrust-related anticline of the Apennine postcollisional thrust belt; it can be roughly subdivided into two areas characterized by different stratigraphic contexts. In the northern and central parts of the field is a structural trap. Reservoir rocks are Serravallian to Tortonian deep marine resedimented conglomerates and sandstones. These deposits represent part of the infill of a middle-upper Miocene foredeep. Reservoir rocks are now thrusted, eroded, and unconformably overlain by lower Pliocene shales, which are the most important seal in this part of the field. In the southern part of the field is a combination trap. Reservoir rocks are upper Tortonian shallow-water sandstones. They lap onto a Tortonian unconformity related to a tectonic phase which split the previous foredeep into minor piggyback basins. The upper Tortonian sandstones are overlain and sealed by Messinian shales and evaporites. Tectonosedimentary evolution of the area and, consequently, areal distribution and geometry of sedimentary bodies - both potential reservoirs and seals - have been reconstructed using a sequence stratigraphy approach. The sedimentary record has been informally subdivided into five main depositional sequences bounded by unconformities or their correlative conformities; classic facies analysis and petrophysical, seismic, and biostratigraphic data have been utilized to define the internal characteristics of each sequence.

  16. Modeling of the nonlinear resonant response in sedimentary rocks

    Energy Technology Data Exchange (ETDEWEB)

    Ten Cate, James A [Los Alamos National Laboratory; Shankland, Thomas J [Los Alamos National Laboratory; Vakhnenko, Vyacheslav O [NON LANL; Vakhnenko, Oleksiy [NON LANL


    We suggest a model for describing a wide class of nonlinear and hysteretic effects in sedimentary rocks at longitudinal bar resonance. In particular, we explain: hysteretic behaviour of a resonance curve on both its upward and downward slopes; linear softening of resonant frequency with increase of driving level; gradual (almost logarithmic) recovery of resonant frequency after large dynamical strains; and temporal relaxation of response amplitude at fixed frequency. Starting with a suggested model, we predict the dynamical realization of end-point memory in resonating bar experiments with a cyclic frequency protocol. These theoretical findings were confirmed experimentally at Los Alamos National Laboratory. Sedimentary rocks, particularly sandstones, are distinguished by their grain structure in which each grain is much harder than the intergrain cementation material. The peculiarities of grain and pore structures give rise to a variety of remarkable nonlinear mechanical properties demonstrated by rocks, both at quasistatic and alternating dynamic loading. Thus, the hysteresis earlier established for the stress-strain relation in samples subjected to quasistatic loading-unloading cycles has also been discovered for the relation between acceleration amplitude and driving frequency in bar-shaped samples subjected to an alternating external drive that is frequency-swept through resonance. At strong drive levels there is an unusual, almost linear decrease of resonant frequency with strain amplitude, and there are long-term relaxation phenomena such as nearly logarithmic recovery (increase) of resonant frequency after the large conditioning drive has been removed. In this report we present a short sketch of a model for explaining numerous experimental observations seen in forced longitudinal oscillations of sandstone bars. According to our theory a broad set of experimental data can be understood as various aspects of the same internally consistent pattern. Furthermore

  17. PUMa - modelling the groundwater flow in Baltic Sedimentary Basin (United States)

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


    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/ Project web-site:

  18. Astronomical forcing and geochronological application of sedimentary cycles in the Mediterranean Pliocene-Pleistocene

    NARCIS (Netherlands)

    Hilgen, F.J.


    A new, astronomically calibrated time scale is presented for the Mediterranean Pliocene based on the correlation of sedimentary cycles to astronomical curves which describe the quasi-periodic variations in the Earth's orbit during the last 5.5 Ma. These sedimentary cycles are found in a continuous d

  19. Stratigraphic Correlation of Middle Triassic Sequences among Different Paleogeographic Sedimentary Facies in South China

    Institute of Scientific and Technical Information of China (English)


    Affected by the Indosinian movement, the sediments in the main part of South China, Yangtzeplatform, started to transform from marine to continental during the Middle Triassic. In the meantime, a noticeable paleogeographic and sedimentary facies differentiation occurred in the marginal regions of the platforms and produced completely different lithologic and paleontologicsequences in various paleogeographic gradients and sedimentary facies areas, which brought about the difficulties for the stratigraphic correlation based on the traditional stratigraphies. This paper proposes to use some characteristic environmental events as the markers of the stratigraphic corre lation across various paleogeographic sedimentary facies, considering that some distinctive regionalenvironmental events should have affected at the same time on the entire basin or the connectedsedimentary regions and produced some closely related sedimentary records in the stratigraphic sequences though the affected intensity and recorded pattern might be different among the regions.The change of violent relative sea level (generally water depth) and the alteration of tectonic activity summarized from the dynamic mechanism of sedimentation are the best markers of environmental events for stratigraphic correlation. Based on the analysis and recognition of some significantenvironmental events at the typical stratigraphic sequences from various paleogeographic sedimentary facies and combined with the consideration of the variations in expressed form and strength fthe events among different paleogeographic gradients and sedimentary facies, the stratigraphic sequences from different sedimentary facies can be easily correlated directly. Furthermore, the evolutionary history of the whole sedimentary basin can be clearly established.

  20. Age and sedimentary record of inland eolian sediments in Lithuania, NE European Sand Belt

    DEFF Research Database (Denmark)

    Kalińska-Nartiša, Edyta; Thiel, Christine; Nartišs, Maris


    in any detail. The sedimentary structural-textural features are investigated and a chronology was derived using optically stimulated luminescence on both quartz and feldspar. The sedimentary structures and the rounding and surface characteristics of the quartz grains argue for a predominance of eolian...

  1. Well-log based prediction of temperature models in the exploration of sedimentary settings

    DEFF Research Database (Denmark)

    Fuchs, Sven; Förster, Andrea; Wonik, Thomas

    ) developed for matrix TC of sedimentary rocks. The equations resulted from a statistical analysis of an artificial set of mineral assemblages (consisting of 15 rock-forming minerals) typical for the different types of sedimentary rocks. The matrix TC was transformed into bulk TC by using a well-log derived...

  2. The sedimentary dynamics in natural and human-influenced delta channel belts

    NARCIS (Netherlands)

    Hobo, N.


    This study investigates the increased anthropogenic influence on the within-channel belt sedimentary dynamics in the Rhine delta. To make this investigation, the sedimentary dynamics within the life-cycle of a single channel belt were reconstructed for three key periods of increasing human impact, w

  3. Sedimentary process control on carbon isotope composition of sedimentary organic matter in an ancient shallow-water shelf succession (United States)

    Davies, S. J.; Leng, M. J.; Macquaker, J. H. S.; Hawkins, K.


    Source and delivery mechanisms of organic matter are rarely considered when interpreting changing δ13C through sedimentary successions even though isotope excursions are widely used to identify and correlate global perturbations in the carbon cycle. Combining detailed sedimentology and geochemistry we demonstrate how organic carbon abundance and δ13C values from sedimentary organic matter from Carboniferous-aged mudstones are influenced by the proportion of terrestrial versus water column-derived organic matter. Silt-bearing clay-rich shelf mudstones that were deposited by erosive density flows are characterized by 1.8-2.4% organic carbon and highδ13C values (averaging -22.9 ± 0.3‰, n = 12). Typically these mudstones contain significant volumes of terrestrial plant-derived material. In contrast, clay-rich lenticular mudstones, with a marine macrofauna, are the products of the transport of mud fragments, eroded from pre-existing water-rich shelfal muds, when shorelines were distant and biological productivity in the water column was high. Higher organic carbon (2.1-5.2%) and lowerδ13C values (averaging -24.3 ± 0.5‰, n = 11) characterize these mudstones and are interpreted to reflect a greater contribution by (isotopically more negative) amorphous organic matter derived from marine algae. Differences in δ13C between terrestrial and marine organic matter allow the changing proportions from different sources to be tracked through this succession. Combining δ13C values with zirconium (measured from whole rock), here used as a proxy for detrital silt input, provides a novel approach to distinguishing mudstone provenance and ultimately using δ13C to identify oil-prone organic matter in potential source rocks. These results have important implications for using bulk organic matter to identify and characterize global C-isotope excursions.

  4. Sedimentary architecture and depositional evolution of the Quaternary coastal plain of Maricá, Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    André Luiz Carvalho da Silva

    Full Text Available The coastal geomorphology of Maricá (Rio de Janeiro state is characterized by a large lagoon and by two sandy barriers that confine a series of small isolated chain-like lagoons. Data collected from ground-penetrating radar and boreholes from the central coastal plain of Maricá provided information on the sedimentary architecture and evolution of this area in the Quaternary. Six lithological units were identified comprising three depositional sequences limited by erosional surfaces, related to barrier-lagoon systems that migrated onshore, offshore, and longshore, giving rise to a sedimentary deposit 25 m thick or more. The data reveal a retrograding barrier overlying a basal mud unit which rests in unconformity upon Precambrian basement, thus characterizing an important Pleistocene transgression. A second Pleistocene barrier of 45,000 cal years BP migrated over a lagoonal mud unit (48,000-45,000 cal years BP reaching over the previous barrier. A progradational phase followed due to a fall of sea level. A long interval of erosion of the barrier created an unconformity that represents the Pleistocene-Holocene boundary. A beachrock in nearby Itaipuaçu, 100 m offshore from the present-day beach, dated as 8,500 cal years BP marks the onset of Holocene sedimentation due to gradually rising sea level, which continued until at about 5,000 years ago. This promoted the retrogradation of the barrier-lagoon system. A brief episode of progradation is observed as a series of paleobeach scarps. Today's rising sea level is causing the retrogradation of the barrier.

  5. A Lower Rhine flood chronology based on the sedimentary record of an abandoned channel fill (United States)

    Toonen, W. H. J.; Winkels, T. G.; Prins, M. A.; de Groot, L. V.; Bunnik, F. P. M.; Cohen, K. M.


    The Bienener Altrhein is an abandoned channel of the Lower Rhine (Germany). Following a late 16th century abandonment event, the channel was disconnected from the main stream and the oxbow lake gradually filled with 8 meters of flood deposits. This process still continues today. During annual floods, a limited proportion of overbank discharge is routed across the oxbow lake. Large floods produce individual flood layers, which are visually recognized in the sedimentary sequence. Based on the sedimentary characteristics of these event layers, we created a ~450-year flood chronology for the Lower Rhine. Laser-diffraction grain size measurements were used to assess relative flood magnitudes for individual flood event layers. Continuous sampling at a ~2 cm interval provided a high-resolution record, resolving the record at an annual scale. Standard descriptive techniques (e.g., mean grain size, 95th percentile, % sand) and the more advanced 'end member modelling' were applied to zoom in on the coarse particle bins in the grain size distributions, which are indicative of higher flow velocities. The most recent part of the record was equated to modern discharge measurements. This allows to establish relations between deposited grain size characteristics in the abandoned channel and flood magnitudes in the main river. This relation can also be applied on flood event layers from previous centuries, for which only water level measurements and historical descriptions exist. This makes this method relevant to expand data series used in flood frequency analysis from 100 years to more than 400 years. To date event-layers in the rapidly accumulated sequence, we created an age-depth model that uses organic content variations to tune sedimentation rates between the known basal and top ages. No suitable identifiable organic material for radiocarbon dating was found in the cores. Instead, palynological results (introduction of agricultural species) and palaeomagnetic secular

  6. The control of syndepositional faulting on the Eogene sedimentary basin fills of the Dongying and Zhanhua sags,Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    LIN Changsong; ZHENG Herong; REN Jianye; LIU Jingyan; Qiu Yigang


    The Dongying and Zhanhua sags are the major hydrocarbon exploration and production subbasins in the Bohai Bay Basin. Integrated analysis of the sedimentary basin fills has shown that the syndepositional faults and their arrangement styles exerted an important influence on the development and distribution of the Eogene depositional systems. The sedimentary filling evolution of the subbasins reflects the general control of the episodic rifting process. The major long-term active normal faults formed a series of paleogeomorphic accident or slopebreak zones that commonly delineated the subsidiary palaeostructural units and the depositional facies tracts and constrained the general distribution of sedimentary facies zones. The central sag boundary fault slopebreak zones usually determined the distribution of the depocenters of terrestrial clastic depositional systems, particularly the Iowstand fans or deltaic depositional systems, and have proven to be the economically important targets for the exploration of subtle sandstone reservoirs. A variety of syndepositional fault arrangement patterns, including the parallel, en echelon, combo-like, broom-like fault systems and the fault overlap or transfer zones,have been recognized in the subbasins. They generated distinctive geomorphic features and exerted a direct influence on sediment dispersal and sandbody distribution during the Eogene synrift stage. It is the key for the prediction of depositional systems tracts and reservoir sandstones to investigate the activity and distribution of the fault slopebreak zones and reconstruct the structural paleogeomorphy in different basin filling stages of the basin evolution.

  7. Sedimentary Records of the Paleohurricane Activity in the Bahamas (United States)

    Wallace, E. J.; Donnelly, J. P.; Wiman, C.; Cashman, M.


    Hurricanes pose a threat to human lives and can cause significant destruction of coastal areas. This threat has become more pronounced with recent rises in sea level and coastal populations. Currently, there is a large degree of uncertainty surrounding future changes in tropical cyclone activity. This is due to the limitations of climate models as well as the scarcity and unreliability of the current observational record. With so much uncertainty surrounding the current projections of hurricane activity, it is crucial to establish a longer and more accurate historical record. This study uses sediment cores extracted from blueholes in the Bahamas to develop a record of intense hurricane landfalls in the region dating back more than a millennia. The collected cores were sectioned, split, and scanned on an X-ray fluorescence scanner to obtain a high resolution core profile of the sediments' elemental composition and to identify potential sedimentary structures. Age control of the samples was determined using radiocarbon dating, coarse fraction was measured every centimeter, and hurricane event bed frequency was established for each core. We assess the statistical significance of the patterns observed in the sedimentary record using a coupled ocean-atmosphere hurricane model to simulate storms representative of modern climatology. Cores extracted from two blue holes near South Andros Island provide approximately a 1600 year and a 600 year record respectively, with sedimentation rates exceeding 1 cm/year. Both records contain coarse grained event deposits that correlate with known historical intense hurricane strikes in the Bahamas within age uncertainties. The 1600 year record confirms previous hurricane reconstructions from the Caribbean indicating higher tropical cyclone activity from 500 to 1400 CE. In addition, these new high-resolution records indicate elevated intense hurricane activity in the 17th and 18th centuries CE, when activity is also elevated in lower

  8. Origin of sedimentary organic matter at the Northern Cascadia Margin (United States)

    Kaneko, M.; Naraoka, H.


    Gas hydrate in marine sediments may have important roles on global carbon cycle and climatic change. We examined origins of sedimentary organic matter and bacterial activity in deep and hydrate-bearing sediment cored in Site U1327 and U1328 at northern Cascadia Margin by IODP Exp311, using σ13C of total organic carbon (TOC), σ15N of total nitrogen (TN), σ34S of total sulfur (TS), and σ13C of biomarkers in hydrocarbon fraction. In both sites, TOC/TN ratios and σ13C of TOC values ranged from 5.5 to 18.0 and -25.7 to -21.5 ‰, respectively, suggesting that sedimentary organic matter is a mixture of terrestrial and marine sources. Long chain (n)-alkanes (C27, C29, and C30), known as biomarkers of terrestrial higher plant were most abundant components (up to ~50 μg/gCorg) through down to 300 mbsf, and their σ13C values (-34.3 to -28.7 ‰) reveal their C3 plant origin. In addition, very long-chain alkene (C37) occurred in some sediments, which suggests the blooming by coccolithophore in the past. σ34S of TS values at both sites show large variation between -30 to +20 ‰. Most of σ34S of TS values were less than present σ34S value of seawater sulfate (+20.3 ‰). This is attributable to isotope fractionation during microbial sulfate reduction. Crocetenes including one double bond occurred in deep sediments with higher σ13C values (-23 ‰) than the reported σ13C values (< ~ -100 ‰, Elvert et al, 2000), providing possibility of heterotrophic archaea using marine organic matter as a carbon source. Pentamethylicosane (PMI) was detected in relatively high concentrations at 249 mbsf at Site U1328 and its σ13C value was -46.4 ‰. This PMI could be chemoautotrophic archaea in origin such as methanogen. Diploptene was also detected in most sediments with the σ13C value of -37 to -35 ‰, probably being characteristic of chemoautotrophic bacteria.

  9. Glacially induced stresses in sedimentary rocks of northern Poland (United States)

    Trzeciak, Maciej; Dąbrowski, Marcin


    During the Pleistocene large continental ice sheets developed in Scandinavia and North America. Ice-loading caused bending of the lithosphere and outward flow in the mantle. Glacial loading is one of the most prominent tectono-mechanical event in the geological history of northern Poland. The Pomeranian region was subjected several times to a load equivalent of more than 1 km of rocks, which led to severe increase in both vertical and horizontal stresses in the upper crustal rocks. During deglaciation a rapid decrease in vertical stress is observed, which leads to destabilization of the crust - most recent postglacial faults scarps in northern Sweden indicate glacially induced earthquakes of magnitude ~Mw8. The presence of the ice-sheet altered as well the near-surface thermal structure - thermal gradient inversion is still observable in NW Poland. The glacially related processes might have left an important mark in the sedimentary cover of northern Poland, especially with regard to fracture reopening, changes in stress state, and damage development. In the present study, we model lithospheric bending caused by glacial load, but our point of interest lies in the overlying sediments. Typical glacial isostatic studies model the response of (visco-) elastic lithosphere over viscoelastic or viscous asthenosphere subjected to external loads. In our model, we introduce viscoelastic sedimentary layers at the top of this stack and examine the stress relaxation patterns therein. As a case study for our modelling, we used geological profiles from northern Poland, near locality of Wejherowo, which are considered to have unconventional gas potential. The Paleozoic profile of this area is dominated by almost 1 km thick Silurian-Ordovician shale deposits, which are interbedded with thin and strong limestone layers. This sequence is underlain by Cambrian shales and sandstones, and finally at ~3 km depth - Precambrian crystalline rocks. Above the Silurian there are approximately

  10. New Insights into the Sedimentary Dynamics along Carbonate Slopes (United States)

    Wunsch, Marco; Betzler, Christian; Lindhorst, Sebastian; Lüdmann, Thomas; Eberli, Gregor


    Hydroacoustic, sedimentological and seismic data of the leeward slope of Great Bahama Bank and the windward slope of the adjacent Cay Sal Bank provide new insights into carbonate platform slope sedimentation. Our study focuses on the diversity and complexity of the slope morphologies and sedimentary patterns which characterize the youngest high-frequency sequence, forming since the Last Glacial Maximum. It is shown that both carbonate platform slopes are dissected by furrows, gullies and channels which are genetically not related. Along the windward slope of Cay Sal Bank, toe of slope erosion, in conjunction with the local tectonic regime is responsible for channel incisions. Our data show that these channels were active during the regression after the last interglacial highstand of sea level. During this regression, downwelling transported platform sediment downslope, which was redistributed along the slope by contour currents. It is also shown that large mass transport complexes at the leeward slope of Great Bahama Bank formed during the last sea level lowstand, probably triggered by the release of pore-water pressure. These MTC created a complex slope morphology of gullies and scarps. These gullies act as a point source by confining the exported platform sediments during the present day sea level highstand.

  11. Sedimentary records of mercury stable isotopes in Lake Michigan

    Directory of Open Access Journals (Sweden)

    Runsheng Yin


    Full Text Available Abstract Mercury (Hg concentrations and Hg isotopic composition were investigated in three sediment cores in Lake Michigan (LM. Two cores were collected from Green Bay, a region heavily impacted by Hg contamination and one core from an offshore region of LM absent of direct point source Hg. Historical trends of Hg influxes suggest increased Hg deposition began in the 1890s in Green Bay and in the early 1800’s in offshore LM. Recently deposited sediment reflecting more anthropogenic influence shows similar δ202 Hg values (-1.0 to -0.5‰ for all three cores however, deep core sediments, reflecting pre-industrial eras, show much lower δ202Hg values (-1.7 to -1.2‰. Using a binary mixing model based on δ202Hg signatures, the proportion of anthropogenic Hg was estimated. Model output confirms that Green Bay is more contaminated by local point source than the offshore LM. An increase in positive Δ199Hg values (-0.02 to +0.27‰ was observed from inner Green Bay to the offshore of LM, which may indicate increased input of atmospheric Hg and decreased watershed inputs along this transect. Overall, this study suggests that sedimentary Hg isotopes maybe a useful tracer in understanding Hg sources and history of Hg contamination in large lakes.

  12. Late Cenozoic sedimentary and tectonic history of south Buton, Indonesia (United States)

    Fortuin, A. R.; De Smet, M. E. M.; Hadiwasastra, S.; Van Marle, L. J.; Troelstra, S. R.; Tjokrosapoetro, S.

    A description and interpretation are given of the Upper Cenozoic sedimentary record of south Buton. Various sections and outcrops were studied and sampled for their microfossil content, to provide age and paleobathymetrical data. Together with information from the literature, these data from the base for a geohistory analysis to evaluate the vertical motions. Deposition started some 11 Ma ago, after the main deformation of the island, which was related to the collision of a microplate carrying Buton, with the southeast arm of Sulawesi. Coarse and fine terrigenous debris accumulated in a rapidly subsiding foreland basin; subsidence may have exceeded 100 cm/ka. When the rate of subsidence decreased a late Miocene-early Pliocene period of quiet pelagic sedimentation followed. From the late Pliocene onwards (around 3.5 Ma BP) an overall uplift took place, with rates between 30-120 cm/ka. This drastic change is explained by the collision of Buton with a submerged microcontinent that presently forms the Tukang Besi platform, situated southeast of Buton, which interaction resulted in wrench type tectonics and a clockwise rotation of over 60° for south Buton.

  13. Land subsidence and hydrodynamic compaction of sedimentary basins

    Directory of Open Access Journals (Sweden)

    H. Kooi


    Full Text Available A one-dimensional model is used to investigate the relationship between land subsidence and compaction of basin sediments in response to sediment loading. Analysis of the model equations and numerical experiments demonstrate quasi-linear systems behaviour and show that rates of land subsidence due to compaction: (i can attain a significant fraction (>40% of the long-term sedimentation rate; (ii are hydrodynamically delayed with respect to sediment loading. The delay is controlled by a compaction response time τc that can reach values of 10-5-107 yr for thick shale sequences. Both the behaviour of single sediment layers and multiple-layer systems are analysed. Subsequently the model is applied to the coastal area of the Netherlands to illustrate that lateral variability in compaction-derived land subsidence in sedimentary basins largely reflects the spatial variability in both sediment loading and compaction response time. Typical rates of compaction-derived subsidence predicted by the model are of the order of 0.1 mm/yr but may reach values in excess of 1 mm/yr under favourable conditions.

  14. Igneous-sedimentary petroleum systems; Sistemas petroliferos igneo-sedimentares

    Energy Technology Data Exchange (ETDEWEB)

    Eiras, Jaime Fernandes [Para Univ., Belem, PA (Brazil)]. E-mail:; Wanderley Filho, Joaquim Ribeiro [PETROBRAS S.A., Manaus, AM (Brazil). Unidade de Negocios-BSOL]. E-mail:


    Igneous-sedimentary petroleum systems are mixed systems in which one or more essential elements or processes are related to magmatic events. Many examples worldwide are presented to show the importance of igneous rocks in the exploratory activities, as well as in the petroleum occurrence. Volcanic ash layers are of great importance in stratigraphic correlation and elucidation of structures, particularly when they occur in thick nonfossiliferous strata. They are also good indicators of turbidite deposition where turbidity currents are related to earthquakes generated by magmatic events. Unconventional reservoirs can be created by volcanic eruptions or intrusions, crystallization, reworking, and fracturing. Unaltered igneous rocks can seal vertically and laterally conventional reservoirs due to its excellent cap capacity. Abnormal thermal effect of igneous rocks can compensate the lack of overburden in shallow basins. Structural or combined traps can be formed due to intrusions, such as folded, faulted, and unconformity traps. Porosity can be either primary or secondary, or both. Primary porosity mainly consists of cavities produced by gas volatilization during eruption and cooling. Secondary porosity refers to those pores that result from hydrothermal alteration, recrystallization, and dissolution by groundwater, and tectonic stress. It includes intercrystalline pores formed by crystallization of various secondary minerals, dissolution pores, and tectonic fractures. New technologies of petroleum development and production are encouraging to search for oil and gas within igneous rocks, and new discoveries are expected. (author)

  15. Edge detection in gravity field of the Gheshm sedimentary basin

    Directory of Open Access Journals (Sweden)

    Ali Akbar Hosseini


    Full Text Available Edge detection and edge enhancement techniques play an essential role in interpreting potential field data. This paper describes the application of various edge detection techniques to gravity data in order to delineate the edges of subsurface structures. The edge detection methods comprise analytic signal, total horizontal derivative (THDR, theta angle, tilt angle, hyperbolic of tilt angle (HTA, normalised total horizontal gradient (TDX and normalised horizontal derivative (NTHD. The results showed that almost all filters delineated edges of anomalies successfully. However, the capability of these filters in edge detection decreased as the depth of sources increased. Of the edge enhancement filters, normalized standard deviation filter provided much better results in delineating deeper sources. The edge detection techniques were further applied on a real gravity data from the Gheshm sedimentary basin in the Persian Gulf in Iran. All filters specified a northeast-southwest structural trend. The THDR better outlined the structural morphology and trend. Moreover, it indicated the salt plugs much better than other filters. Analytic signal and THDR successfully enhanced the edges of the shorter wavelength residual structures. Normalized standard deviation (NSTD, TDX and hyperbolic of tilt angle (HTA filters highlighted the likely fault pattern and lineaments, with a dominant northeast-southwest structural trend. This case study shows that the edge detection techniques provides valuable information for geologists and petroleum engineers to outline the horizontal location of geological sources including salt plugs and stand out buried faults, contacts and other tectonic and geological features.

  16. Antarctic Cenozoic climate history from sedimentary records: ANDRILL and beyond. (United States)

    McKay, R M; Barrett, P J; Levy, R S; Naish, T R; Golledge, N R; Pyne, A


    Mounting evidence from models and geological data implies that the Antarctic Ice Sheet may behave in an unstable manner and retreat rapidly in response to a warming climate, which is a key factor motivating efforts to improve estimates of Antarctic ice volume contributions to future sea-level rise. Here, we review Antarctic cooling history since peak temperatures of the Middle Eocene Climatic Optimum (approx. 50 Ma) to provide a framework for future initiatives to recover sediment cores from subglacial lakes and sedimentary basins in Antarctica's continental interior. While the existing inventory of cores has yielded important insights into the biotic and climatic evolution of Antarctica, strata have numerous and often lengthy time breaks, providing a framework of 'snapshots' through time. Further cores, and more work on existing cores, are needed to reconcile Antarctic records with the more continuous 'far-field' records documenting the evolution of global ice volume and deep-sea temperature. To achieve this, we argue for an integrated portfolio of drilling and coring missions that encompasses existing methodologies using ship- and sea-ice-/ice-shelf-based drilling platforms as well as recently developed seafloor-based drilling and subglacial access systems. We conclude by reviewing key technological issues that will need to be overcome.

  17. Sedimentary environments of the Cenozoic sedimentary debris found in the moraines of the Grove Mountains, east Antarctica and its climatic implications

    Institute of Scientific and Technical Information of China (English)

    FANG Aimin; LIU Xiaohan; LEE Jong Ik; LI Xiaoli; HUANG Feixin


    During the field work of the 1998~1999's and 1999~2000's Chinese National Antarctic Research Expedition (CHNARE) in the Grove Mountains, east Antarctica, some Cenozoic sedimentary debris are found in two terminal moraine banks over the blue ice near Harding Mount in the center of this region. All the debris are of characteristics of glaciogenic diamicton and belong to the products of the glacial movements of the East Antarctic Ice Sheet. In this paper, the authors make a detailed study on the sedimentary environments of the sedimentary debris through petrologic, sedimentological, mineralogical, and geo-chemical methods. Characteristics of their sedimentary textures and structures, grain size distributions, quartz grains' surface textures and features, together with their geo-chemical compositions all show that these sedimentary rocks are a kind of subglacial lodgement tills which are deposited in the ice sheet frontal area by reactions of glacial movements and glaciogenic melt water. Their palaeoenvironmental implications in revealing the retreat history of East Antarctic Ice Sheet are discussed. The authors draw the conclusion from current study that the glacial frontal of the East Antarctica Ice Sheet might have been retreated to this area during the Pliocene Epoch, which represents a warm climate event accompanied by a large-scale ice sheet retreat in Antarctica at that time.

  18. Jasrouxite, a new Pb-Ag-As-Sb member of the lillianite homologous series from Jas Roux, Hautes Alpes, France

    DEFF Research Database (Denmark)

    Topa, Dan; Makovicky, Emil; Favreau, Georges


    The thallium-rich sulfosalt deposit of Jas Roux, situated in the Pelvoux Massif (Hautes-Alpes de´partement, France), occurs in a Triassic sedimentary series. Jasrouxite belongs to the early lead-containing stages of the Tl–As–Sb period of mineralization. It occurs in a silicified gangue, along wi...

  19. Series Transmission Line Transformer (United States)

    Buckles, Robert A.; Booth, Rex; Yen, Boris T.


    A series transmission line transformer is set forth which includes two or more of impedance matched sets of at least two transmissions lines such as shielded cables, connected in parallel at one end ans series at the other in a cascading fashion. The cables are wound about a magnetic core. The series transmission line transformer (STLT) which can provide for higher impedance ratios and bandwidths, which is scalable, and which is of simpler design and construction.

  20. Fourier Series Operating Package (United States)

    Charnow, Milton L.


    This report presents a computer program for multiplying, adding, differentiating, integrating, "barring" and scalarly multiplying "literal" Fourier series as such, and for extracting the coefficients of specified terms.

  1. Cenozoic uplift on the West Greenland margin: active sedimentary basins in quiet Archean terranes. (United States)

    Jess, Scott; Stephenson, Randell; Brown, Roderick


    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

  2. Sedimentary Characteristics and Paleoenvironmental Records of Zabuye Salt Lake, Tibetan Plateau, since 128 ka BP

    Institute of Scientific and Technical Information of China (English)


    This paper for the first time reveals high-resolution core records of Zabuye Salt Lake in the interior of the Qinghai-Tibet Plateau. According to 1346 samples taken continuously, relatively accurate 14C, U-series disequilibrium and ESR ages have been obtained, thus revealing that the lake core ages from 0 to 83.63 m of hole SZK02 are ~800 to over 128 ka. In the paper, the lake core sedimentary characteristics (including the lithologies and mineral assemblages) are analyzed in detail and correlated with ostracod assemblages Ⅰ to ⅩⅩ and sporopollen zones A to I, and on the basis of an integrated analysis of the δ18O values of authigenic calcium-magnesium carbonate and environmental proxies of minerals, sporopollen and microfossils in the lake core, a correlation has been made of oxygen isotope change between this lake core and the Greenland GISP2 and GRIP and Guliya ice cores, and the climate of Zabuye Salt Lake since 128 ka BP is divided into the last interglacial stage (including substages e, d, c, b and a) of oxygen isotope stage (OIS) 5, early glacial stadial of the last glacial stage of OIS 4, interglacial stadial of the last glacial stage of OIS 3, late glacial stadial of the last glacial stage or Last Glacial Maximum of OIS 2 and postglacial state of OIS 1; in addition, 6 Heinrich (H6-H1) events, Younger Dryas event and 8.2 ka BP cold event have been recognized.

  3. Molecular and spectroscopic analysis of non-hydrolyzable sedimentary organic matter from the St. Lawrence Estuary (United States)

    Ibrahim, M.; Simpson, A. J.; Gelinas, Y.


    Sediments are the ultimate long-term sink for organic carbon (OC) on Earth, thus playing an important role in the global cycles of O2 and CO2. Estuaries and river deltas are major conduits for terrestrial organic matter (OM) into marine systems, where it is mixed with locally produced OM and is eventually deposited and buried in the sediment bed. About 45% of global OC burial occurs along these river deltas and estuaries (Hedges and Keil, 1995), therefore it is of interest to follow OM deposition and preservation in these terrestrial to marine transition zones. We chemically fractionated bulk OM from a series of sediments from the St. Lawrence Estuary and Gulf into distinct reactivity classes. We define three such OM fractions based on pioneering work by Hedges and Keil (1995) who classified OM based on chemical reactivities: labile (degradable at similar rate under oxic and anoxic conditions), non-hydrolyzable (degraded primarily under oxic conditions), and refractory (preserved on long time scales independently of redox conditions). Here we present data on the elemental (C and N), isotopic (δ13C and δ15N) and spectroscopic (FTIR, HR-MAS 1H/13C NMR) characterization of the different fractions, focusing primarily on the non-hydrolyzable fraction because of its importance in the long-term burial of OC below the seafloor. We used mild oxidation methods (cupric oxide and ruthenium tetroxide oxidation) followed by chromatographic analysis of the oxidation products. Combining results from the bulk and molecular analytical techniques provides insights into the composition and cycling of non-hydrolyzable OM in transitional system, from which OM preservation can be better understood. Hedges, J. I., Keil, Richard G. (1995). "Sedimentary organic matter preservation: an assessment and speculative synthesis." Marine Chemistry 49(2-3): 81-115.

  4. High-resolution sedimentary records of heavy metals in Guangzhou section of the Pearl River, South China

    Institute of Scientific and Technical Information of China (English)


    The sedimentary feature and variation of heavy metals in ca. 100 years, especially in the last three decades, in the riverbed of Guangzhou section of the Pearl River were revealed by the sedimentary heavy metal fluxes and total organic carbon (TOC) in a 210Pb-dated sedimentary core. It is suggested that the historical changes of heavy metal contamination can be recorded by pollutant sedimentary fluxes rather than by their concentrations. The heavy metal contamination in the river section was divided into 6 sedimentary historical stages of 3 groups, which correspond to the economic development and regional urbanization process.

  5. 1.8 Billion Years of Detrital Zircon Recycling Calibrates a Refractory Part of Earth's Sedimentary Cycle. (United States)

    Hadlari, Thomas; Swindles, Graeme T; Galloway, Jennifer M; Bell, Kimberley M; Sulphur, Kyle C; Heaman, Larry M; Beranek, Luke P; Fallas, Karen M


    Detrital zircon studies are providing new insights on the evolution of sedimentary basins but the role of sedimentary recycling remains largely 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 sedimentary 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 sedimentary cycle by showing that recycling dominates sedimentary provenance for the refractory mineral zircon.

  6. Mass transport-related stratal disruption and sedimentary products (United States)

    Ogata, Kei; Mutti, Emiliano; Tinterri, Roberto


    is quite common in the sedimentary record though still poorly reported and understood. Mutti and Carminatti (oral presentation from Mutti et al., 2006) have suggested to call these deposits "blocky-flow deposits", i.e. the deposit of a complex flow that is similar to a debris flow, or hyper-concentrated flow, except that it carries also out-size coherent and internally deformed blocks (meters to hundreds of meters across) usually arranged in isolated slump folds. The origin of blocky flows is difficult to understand on presently available data, particularly because it involves the contemporary origin of coherent slide blocks and a plastic flow that carries them as floating elements over considerable run-out distances. The recognition of the above-mentioned characteristics should be a powerful tool to discriminate sedimentary and tectonic "chaotic" units within accretionary systems, and to distinguish submarine landslide deposits transported as catastrophic blocky flows (and therefore part of the broad family of sediment gravity flows) from those in which transport took place primarily along shear planes (i.e. slumps, coherent slides), also highlighting a possible continuum from slides to turbidity currents. The discussed examples fall into a broad category of submarine slide deposits ranging from laterally extensive carbonate megabreccias (lower-middle Eocene "megaturbidites" of the south-central Pyrenees), to mass transport deposits with a very complex internal geometry developed in a highly tectonically mobile basin (upper Eocene - lower Oligocene Ranzano Sandstone, northern Apennines). References: Mutti, E., Carminatti, M., Moreira, J.L.P. & Grassi, A.A. (2006) - Chaotic Deposits: examples from the Brazilian offshore and from outcrop studies in the Spanish Pyrenees and Northern Apennines, Italy. - A.A.P.G. Annual Meeting, April 9-12, Houston, Texas.

  7. Long-term sedimentary recycling of rare sulphur isotope anomalies. (United States)

    Reinhard, Christopher T; Planavsky, Noah J; Lyons, Timothy W


    The accumulation of substantial quantities of O2 in the atmosphere has come to control the chemistry and ecological structure of Earth's surface. Non-mass-dependent (NMD) sulphur isotope anomalies in the rock record are the central tool used to reconstruct the redox history of the early atmosphere. The generation and initial delivery of these anomalies to marine sediments requires low partial pressures of atmospheric O2 (p(O2); refs 2, 3), and the disappearance of NMD anomalies from the rock record 2.32 billion years ago is thought to have signalled a departure from persistently low atmospheric oxygen levels (less than about 10(-5) times the present atmospheric level) during approximately the first two billion years of Earth's history. Here we present a model study designed to describe the long-term surface recycling of crustal NMD anomalies, and show that the record of this geochemical signal is likely to display a 'crustal memory effect' following increases in atmospheric p(O2) above this threshold. Once NMD anomalies have been buried in the upper crust they are extremely resistant to removal, and can be erased only through successive cycles of weathering, dilution and burial on an oxygenated Earth surface. This recycling results in the residual incorporation of NMD anomalies into the sedimentary record long after synchronous atmospheric generation of the isotopic signal has ceased, with dynamic and measurable signals probably surviving for as long as 10-100 million years subsequent to an increase in atmospheric p(O2) to more than 10(-5) times the present atmospheric level. Our results can reconcile geochemical evidence for oxygen production and transient accumulation with the maintenance of NMD anomalies on the early Earth, and suggest that future work should investigate the notion that temporally continuous generation of new NMD sulphur isotope anomalies in the atmosphere was likely to have ceased long before their ultimate disappearance from the rock record.

  8. Correlating biodegradation to magnetization in oil bearing sedimentary rocks (United States)

    Emmerton, Stacey; Muxworthy, Adrian R.; Sephton, Mark A.; Aldana, Milagrosa; Costanzo-Alvarez, Vincenzo; Bayona, German; Williams, Wyn


    A relationship between hydrocarbons and their magnetic signatures has previously been alluded to but this is the first study to combine extensive geochemical and magnetic data of hydrocarbon-associated samples. We report a detailed study that identifies a connection between magnetic mineralogy and oil biodegradation within oil-bearing sedimentary units from Colombia, Canada Indonesia and the UK. Geochemical data reveal that all the oil samples are derived from mature type-II kerogens deposited in oxygen-poor environments. Biodegradation is evident to some extent in all samples and leads to a decrease in oil quality through the bacterially mediated conversion of aliphatic hydrocarbons to polar constituents. The percentage of oil components and the biodegradation state of the samples were compared to the magnetic susceptibility and magnetic mineralogy. A distinct decrease in magnetic susceptibility is correlated to decreasing oil quality and the amount of extractable organic matter present. Further magnetic characterization revealed that the high quality oils are dominated by pseudo-single domain grains of magnetite and the lower quality oils by larger pseudo-single domain to multidomain grains of magnetite and hematite. Hence, with decreasing oil quality there is a progressive dominance of multidomain magnetite as well as the appearance of hematite. It is concluded that biodegradation is a dual process, firstly, aliphatic hydrocarbons are removed thereby reducing oil quality and secondly, magnetic signatures are both created and destroyed. This complex relationship may explain why controversy has plagued previous attempts to resolve the connection between magnetics and hydrocarbon deposits. These findings reinforce the importance of bacteria within petroleum systems as well as providing a platform for the use of magnetization as a possible exploration tool to identify subsurface reservoirs and a novel proxy of hydrocarbon migration.

  9. Biogenic syngenetic pyrite from tuffaceous sedimentary RF3-V rocks (United States)

    Kozyreva, Irina; Nikulova, Natalia


    Biogenic framboidal pyrite was found in intraformational tuffaceous sedimentary gravelites, within basic volcanites (RF3-V) in Subpolar Urals (Sablya Ridge). Pyrite grains (Fe 44.07-44,33, S 50.22-53.31 wt. %) are composed of ball-like microconcretions, sometimes intergrown with crystals of pentagondodecahedron and cubic habit. The microconcretions (20 to 40 mcm) are roundish and composed of microcrystals, which end faces form spherical surface. The nuclei of the microconcretions are represented by frambohedrons 4-5 mcm in size, which are pyritized cells of sulphate-reducing colonial coccoid microfossils. The formation of the frambohedrons occurred synchronously to sedimentation in stagnant reducing environment at interaction of biogenic hydrogen sulphide with water-dissolved iron. The biogenic hydrogen sulphide is reduced by microorganisms in the conditions of free and unrestricted access of dissolved sulphate ions sourced from sulphur of fumarole gases. Iron came from washed-out basic volcanites. The growth of outer radial parts of microconcretions occurred during compaction of sediments in diagenetic stage. The quantity of dissolved sulphate and iron during pyrite formation exceeded possibilitites of bacterial "starters" which resulted in the formation of pyrites of other morphological varieties. This is confirmed by the accretion of concentric rays of the concretions and cubic microcrystals of pyrite in the aggregate grains. The formation of tuffaceous sediments occurred during temporary decrease of volcanic activity in a continuous linear water flow with stagnant areas composed of water-displaced pebbles from underlying metaterrigenous rocks (RF 1-2), which were exposed beyond the development area of volcanic strata, unchanged clasts of recent and synchronously formed basic and medium volcanites with participation of air-driven ashes and influence of volcanic gases in the presence of sulphate-reducing bacteria. The work is financially supported by the Program

  10. Rapid imbibition of water in fractures within unsaturated sedimentary rock (United States)

    Cheng, C.-L.; Perfect, E.; Donnelly, B.; Bilheux, H. Z.; Tremsin, A. S.; McKay, L. D.; DiStefano, V. H.; Cai, J. C.; Santodonato, L. J.


    The spontaneous imbibition of water and other liquids into gas-filled fractures in variably-saturated porous media is important in a variety of engineering and geological contexts. However, surprisingly few studies have investigated this phenomenon. We present a theoretical framework for predicting the 1-dimensional movement of water into air-filled fractures within a porous medium based on early-time capillary dynamics and spreading over the rough surfaces of fracture faces. The theory permits estimation of sorptivity values for the matrix and fracture zone, as well as a dispersion parameter which quantifies the extent of spreading of the wetting front. Quantitative data on spontaneous imbibition of water in unsaturated Berea sandstone cores were acquired to evaluate the proposed model. The cores with different permeability classes ranging from 50 to 500 mD and were fractured using the Brazilian method. Spontaneous imbibition in the fractured cores was measured by dynamic neutron radiography at the Neutron Imaging Prototype Facility (beam line CG-1D, HFIR), Oak Ridge National Laboratory. Water uptake into both the matrix and the fracture zone exhibited square-root-of-time behavior. The matrix sorptivities ranged from 2.9 to 4.6 mm s-0.5, and increased linearly as the permeability class increased. The sorptivities of the fracture zones ranged from 17.9 to 27.1 mm s-0.5, and increased linearly with increasing fracture aperture width. The dispersion coefficients ranged from 23.7 to 66.7 mm2 s-1 and increased linearly with increasing fracture aperture width and damage zone width. Both theory and observations indicate that fractures can significantly increase spontaneous imbibition in unsaturated sedimentary rock by capillary action and surface spreading on rough fracture faces. Fractures also increase the dispersion of the wetting front. Further research is needed to investigate this phenomenon in other natural and engineered porous media.

  11. Postglacial sedimentary infill of the Bricial peatland (Cantabrian Mountains, Spain) (United States)

    Correia, Antonio; Ruiz-Fernández, Jesús; Oliva, Marc; Fernández, Antonio; García-Hernández, Cristina; Gallinar, David


    Bricial is a peatland located in a glaciokarst depression of the Western Massif of the Picos de Europa (NW Spain). The depression is 425 m long and 245 m wide, and it is surrounded by moraines built during the stage of glacial expansion after the maximum advance within the Last Glaciation. In contrast to what happens in other karstic depressions existing in this massif (e.g. Comeya), the thickness and sedimentary infill of this depression is still unknown. With the purpose of better knowing the depression's structure, two electrical resistivity tomographies (ERT)s with different lengths across the Bricial depression were conducted along perpendicular directions; the shortest ERT was done in a NNE-SSW direction with an electrode spacing of 2 m and a total length of 78 m; the longest ERT was done in a WNW-ESE direction with a 5 m electrode spacing and a total length of 195 m. Both ERTs used 40 electrodes in a Wenner configuration. The two ERTs were done in such way that they intersected near an 8 m deep borehole drilled in the area in 2006. A two-dimensional electrical inversion software was used for inverting the apparent electrical resistivity data obtained during the field work into two-dimensional models of electrical resistivity of the ground. The models are a representation of the distribution of the electrical resistivity of the ground to depths of about 14 m along the shortest ERT and 35 m along the longest. In both geoelectrical models the electrical structure is approximately horizontal at the surface (i.e., between 3 to 5 m depth) and is more complex as depth increases. Low resistivity values prevail in most part of the profiles, which is consistent with the sedimentary sequence collected in the area. The 8 m long sedimentary sequence collected from Bricial consists of homogeneous organic-rich sediments. The base of the sequence was dated at 11,150 ± 900 cal yr BP. Taking into account the sedimentation rates and the data inferred from the electrical

  12. Evidence from carbon isotope measurements for diverse origins of sedimentary hydrocarbons (United States)

    Freeman, K. H.; Hayes, J. M.; Trendel, J. M.; Albrecht, P.


    The organic matter found in sedimentary rocks must derive from many sources; not only from ancient primary producers but also from consumers and secondary producers. In all of these organisms, isotope effects can affect the abundance and distribution of 13C in metabolites. Here, by using an improved form of a previously described technique in which the effluent of a gas chromatograph is continuously analysed isotopically, we report evidence of the diverse origins of sedimentary organic matter. The record of 13C abundances in sedimentary carbonate and total organic carbon can be interpreted in terms of variations in the global carbon cycle. Our results demonstrate, however, that isotope variations within sedimentary organic mixtures substantially exceed those observed between samples of total organic carbon. Resolution of isotope variations at the molecular level offers a new and convenient means of refining views both of localized palaeoenvironments and of control mechanisms within the global carbon cycle.

  13. Granulometric analyses of pelites using a sedigraph: Examples from a Volcano-sedimentary environment

    Digital Repository Service at National Institute of Oceanography (India)

    Mascarenhas, A

    This article presents granulometric data of pelites (less than 40 microns) of mixed composition from a volcano-sedimentary environment. The sedigraph serves as an useful tool in the analyses of silt-clay fraction of marine sediments. A cumulative...

  14. Elemental geochemistry of sedimentary rocks at Yellowknife Bay, Gale crater, Mars. (United States)

    McLennan, S M; Anderson, R B; Bell, J F; Bridges, J C; Calef, F; Campbell, J L; Clark, B C; Clegg, S; Conrad, P; Cousin, A; Des Marais, D J; Dromart, G; Dyar, M D; Edgar, L A; Ehlmann, B L; Fabre, C; Forni, O; Gasnault, O; Gellert, R; Gordon, S; Grant, J A; Grotzinger, J P; Gupta, S; Herkenhoff, K E; Hurowitz, J A; King, P L; Le Mouélic, S; Leshin, L A; Léveillé, R; Lewis, K W; Mangold, N; Maurice, S; Ming, D W; Morris, R V; Nachon, M; Newsom, H E; Ollila, A M; Perrett, G M; Rice, M S; Schmidt, M E; Schwenzer, S P; Stack, K; Stolper, E M; Sumner, D Y; Treiman, A H; VanBommel, S; Vaniman, D T; Vasavada, A; Wiens, R C; Yingst, R A


    Sedimentary rocks examined by the Curiosity rover at Yellowknife Bay, Mars, were derived from sources that evolved from an approximately average martian crustal composition to one influenced by alkaline basalts. No evidence of chemical weathering is preserved, indicating arid, possibly cold, paleoclimates and rapid erosion and deposition. The absence of predicted geochemical variations indicates that magnetite and phyllosilicates formed by diagenesis under low-temperature, circumneutral pH, rock-dominated aqueous conditions. Analyses of diagenetic features (including concretions, raised ridges, and fractures) at high spatial resolution indicate that they are composed of iron- and halogen-rich components, magnesium-iron-chlorine-rich components, and hydrated calcium sulfates, respectively. Composition of a cross-cutting dike-like feature is consistent with sedimentary intrusion. The geochemistry of these sedimentary rocks provides further evidence for diverse depositional and diagenetic sedimentary environments during the early history of Mars.

  15. Time Series Momentum

    DEFF Research Database (Denmark)

    Moskowitz, Tobias J.; Ooi, Yao Hua; Heje Pedersen, Lasse


    under-reaction and delayed over-reaction. A diversified portfolio of time series momentum strategies across all asset classes delivers substantial abnormal returns with little exposure to standard asset pricing factors and performs best during extreme markets. Examining the trading activities...... of speculators and hedgers, we find that speculators profit from time series momentum at the expense of hedgers....

  16. Seri Kinship Terminology. (United States)

    Moser, Mary B.; Marlett, Stephen A.

    The Seri language contains over 50 kinship terms and represents one of the most highly elaborated kinship systems described to date. This paper discusses Seri kinship terminology and centers around, but is not limited to, the set of obligatory possessed noun stems that are inflected with the following possessive prefixes": "hi-,""ma-," and "a-."…

  17. Fourier Series Optimization Opportunity (United States)

    Winkel, Brian


    This note discusses the introduction of Fourier series as an immediate application of optimization of a function of more than one variable. Specifically, it is shown how the study of Fourier series can be motivated to enrich a multivariable calculus class. This is done through discovery learning and use of technology wherein students build the…

  18. SERI Wind Energy Program

    Energy Technology Data Exchange (ETDEWEB)

    Noun, R. J.


    The SERI Wind Energy Program manages the areas or innovative research, wind systems analysis, and environmental compatibility for the U.S. Department of Energy. Since 1978, SERI wind program staff have conducted in-house aerodynamic and engineering analyses of novel concepts for wind energy conversion and have managed over 20 subcontracts to determine technical feasibility; the most promising of these concepts is the passive blade cyclic pitch control project. In the area of systems analysis, the SERI program has analyzed the impact of intermittent generation on the reliability of electric utility systems using standard utility planning models. SERI has also conducted methodology assessments. Environmental issues related to television interference and acoustic noise from large wind turbines have been addressed. SERI has identified the causes, effects, and potential control of acoustic noise emissions from large wind turbines.

  19. On the connectivity anisotropy in fluvial Hot Sedimentary Aquifers and its influence on geothermal doublet performance

    DEFF Research Database (Denmark)

    Willems, Cees J.L.; Nick, Hamid; Donselaar, Marinus E.


    This study finds that the geothermal doublet layout with respect to the paleo flow direction in fluvial sedimentary reservoirs could significantly affect pump energy losses. These losses can be reduced by up to 10% if a doublet well pair is oriented parallel to the paleo flow trend compared...... Cretaceous Nieuwerkerk Formation in the West Netherlands Basin. Finally, this study emphasizes the importance of detailed facies architecture modelling for the assessment of both risks and production strategies in Hot Sedimentary Aquifers....

  20. Sedimentary Characteristics and Reservoir Prediction of Paleogene in the East Part of Kuqa Foreland Basin

    Institute of Scientific and Technical Information of China (English)

    Yan Detian; Wang Hua; Wang Jiahao; Wang Qingchen


    Most of the Mesozoic and Cenozoic large-scale hydrocarbon-bearing basins in western China were formed in a similar foreland setting. Hydrocarbon exploration of the Kuqa foreland basin requires research into the sedimentary characteristics and filling evolution of the depositional sequences and their response to the basin process. Based on an analysis of outcrops, well logs and high resolution seismic data, the sedimentary system types and distribution characteristics of the Paleogene in the east part of Kuqa foreland basin were systematically studied. The results show that: ( 1 ) Three types of sedimentary systems are developed in the area: an oxidative salty wide shallow lacustrine system, a fan delta system and an evaporitic bordersea system. (2) The configuration and evolution of the depositional systems of the Paleogene in the Kuqa foreland basin were predominantly determined by foreland tectonism. Vertically, the Paleogene sedimentary sequence can be divided into three parts: the lower, middle and upper depositional system tracts. The lower and upper tracts commonly consist of progradational or aggradational sequences, while the middle part is usually comprised of a set of aggradational to transgressive third-order sequences. Laterally, the sedimentary systems in the east part of the Kuqa foreland basin spread from east to west as a whole, and the sedimentary facies obviously vary from south to north. The sand bodies of the delta front facies are excellent gas reservoirs, characterized by rather thick, extensive and continuous distribution, high porosity and permeability, and just a few barrier beds.

  1. Stratigraphic architecture and forcing processes of the late Neogene Miradouro da Lua sedimentary prism, Cuanza Basin, Angola (United States)

    Cauxeiro, C.; Durand, J.; Lopez, M.


    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 sedimentary 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 sedimentary 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 sedimentary 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

  2. The Death of the Dinosaurs: 27 Years Later (LBNL Summer Lecture Series)

    Energy Technology Data Exchange (ETDEWEB)

    Muller, Rich


    Summer Lecture Series 2006: Rich Muller, a Berkeley Lab physicist, discusses Nobel laureate Luis Alvarez and colleagues' 1979 discovery that an asteroid impact killed the dinosaurs. He also discusses what scientists have learned in the subsequent 27 years. Alvarez's team detected unusual amounts of iridium in sedimentary layers. They attributed the excess iridium to an impact from a large asteroid. His talk was presented June 30, 2006.

  3. Historical Climatology Series (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Historical Climatology Series (HCS) is a set of climate-related publications published by NOAA's National Climatic Data Center beginning in 1978. HCS is...

  4. Multivariate Time Series Search (United States)

    National Aeronautics and Space Administration — Multivariate Time-Series (MTS) are ubiquitous, and are generated in areas as disparate as sensor recordings in aerospace systems, music and video streams, medical...

  5. Long time series

    DEFF Research Database (Denmark)

    Hisdal, H.; Holmqvist, E.; Hyvärinen, V.;

    Awareness that emission of greenhouse gases will raise the global temperature and change the climate has led to studies trying to identify such changes in long-term climate and hydrologic time series. This report, written by the......Awareness that emission of greenhouse gases will raise the global temperature and change the climate has led to studies trying to identify such changes in long-term climate and hydrologic time series. This report, written by the...

  6. Simulations of hydraulic fracturing and leakage in sedimentary basins

    Energy Technology Data Exchange (ETDEWEB)

    Lothe, Ane Elisabeth


    Hydraulic fracturing and leakage of water through the caprock is described from sedimentary basin over geological time scale. Abnormal pressure accumulations reduce the effective stresses in the underground and trigger the initiation of hydraulic fractures. The major faults in the basin define these pressure compartments. In this Thesis, basin simulations of hydraulic fracturing and leakage have been carried out. A simulator (Pressim) is used to calculate pressure generation and dissipitation between the compartments. The flux between the compartments and not the flow within the compartments is modelled. The Griffith-Coulomb failure criterion determines initial failure at the top structures of overpressured compartments, whereas the frictional sliding criterion is used for reactivation along the same fractures. The minimum horizontal stress is determined from different formulas, and an empirical one seems to give good results compared to measured pressures and minimum horizontal stresses. Simulations have been carried out on two datasets; one covering the Halten Terrace area and one the Tune Field area in the northern North Sea. The timing of hydraulic fracturing and amount of leakage has been quantified in the studies from the Halten Terrace area. This is mainly controlled by the lateral fluid flow and the permeability of the major faults in the basin. Low fault permeability gives early failure, while high fault permeabilities results in no or late hydraulic fracturing and leakage from overpressured parts of the basin. In addition to varying the transmissibility of all faults in a basin, the transmissibility across individual faults can be varied. Increasing the transmissibility across faults is of major importance in overpressured to intermediately pressured areas. However, to obtain change in the flow, a certain pressure difference has to be the situation between the different compartments. The coefficient of internal friction and the coefficient of frictional

  7. Rivers on Titan - numerical modelling of sedimentary structures (United States)

    Misiura, Katarzyna; Czechowski, Leszek


    flow and of the sedimentation on Titan and on the Earth. Our preliminary results indicate that suspended load is the main way of transport in simulated Titan's conditions. We also indicate that braided rivers appears for larger range of slope on Titan (e.g. S=0.01-0.04) than on Earth (e.g. S=0.004-0.009). Also, for the same type of river, the grain size on Titan is at least 10 times larger than on Earth (1 cm for Titan versus 1 mm for the Earth). It is very interesting that on Titan braided rivers appear even for very little discharge (e.g. Q=30m3/s) and for very large grain size (e.g. 10 cm). In the future we plan the experimental modelling in sediment basin to confirm results from computer modelling. Acknowledgements We are very grateful to Yaoxin Zhang and Yafei Jia from National Center for Computational Hydroscience and Engineering for providing their program - CCHE2D. References [1] Misiura, K., Czechowski, L., 2015. Numerical modelling of sedimentary structures in rivers on Earth and Titan. Geological Quarterly, 59(3): 565-580. [2] Witek, P., Czechowski, L., 2015. Dynamical modeling of river deltas on Titan and Earth. Planet. Space. Sci., 105: 65-79.

  8. Late Quaternary sedimentary features of Bear Lake, Utah and Idaho (United States)

    Smoot, J.P.


    Bear Lake sediments were predominantly aragonite for most of the Holocene, reflecting a hydrologically closed lake fed by groundwater and small streams. During the late Pleistocene, the Bear River flowed into Bear Lake and the lake waters spilled back into the Bear River drainage. At that time, sediment deposition was dominated by siliciclastic sediment and calcite. Lake-level fluctuation during the Holocene and late Pleistocene produced three types of aragonite deposits in the central lake area that are differentiated primarily by grain size, sorting, and diatom assemblage. Lake-margin deposits during this period consisted of sandy deposits including well-developed shoreface deposits on margins adjacent to relatively steep gradient lake floors and thin, graded shell gravel on margins adjacent to very low gradient lake-floor areas. Throughout the period of aragonite deposition, episodic drops in lake level resulted in erosion of shallow-water deposits, which were redeposited into the deeper lake. These sediment-focusing episodes are recognized by mixing of different mineralogies and crystal habits and mixing of a range of diatom fauna into poorly sorted mud layers. Lake-level drops are also indicated by erosional gaps in the shallow-water records and the occurrence of shoreline deposits in areas now covered by as much as 30 m of water. Calcite precipitation occurred for a short interval of time during the Holocene in response to an influx of Bear River water ca. 8 ka. The Pleistocene sedimentary record of Bear Lake until ca. 18 ka is dominated by siliciclastic glacial fl our derived from glaciers in the Uinta Mountains. The Bear Lake deep-water siliciclastic deposits are thoroughly bioturbated, whereas shallow-water deposits transitional to deltas in the northern part of the basin are upward-coarsening sequences of laminated mud, silt, and sand. A major drop in lake level occurred ca. 18 ka, resulting in subaerial exposure of the lake floor in areas now covered by

  9. On Sums of Numerical Series and Fourier Series (United States)

    Pavao, H. Germano; de Oliveira, E. Capelas


    We discuss a class of trigonometric functions whose corresponding Fourier series, on a conveniently chosen interval, can be used to calculate several numerical series. Particular cases are presented and two recent results involving numerical series are recovered. (Contains 1 note.)

  10. Provenance of zircon of the lowermost sedimentary cover, Estonia, East-European Craton

    Directory of Open Access Journals (Sweden)

    Konsa, M.


    Full Text Available Bulk and accessory mineral composition of fresh and weathered crystalline rocks, and sedimentary deposits overlying the crystalline-sedimentary unconformity have been examined in core samples from 28 drill holes in Estonia. Before the Late Vendian to Early Cambrian regional subsidence and sedimentation, the region represented a flat plateau within the Svecofennian Domain. Palaeo-and Mesoproterozoic crystalline rocks, regardless their different initial mineral composition, subcrop under the Upper Vendian/Lower Cambrian sedimentary cover as usually intensely weathered rocks (saprolites composed of residual quartz, altered micas and prevailing clay minerals mainly of the kaolinite group. Thus, the bulk mineral composition of any basement crystalline rocks imparts no specific inherited rock-forming minerals into the covering sedimentary rocks. From the variety of accessory and opaque minerals of crystalline rocks, only zircon populations survived in saprolites. Crystalline rocks of different origin yield different zircons. Relationships between the zircon typology of the basement rocks having specific areas of distribution and the sedimentary rocks immediately overlying those crystalline rocks were the main subject of this study. The result is that siliciclastic sedimentary rocks covering weathered crystalline rocks only in places inherited zircons with typological features characteristic of specific basement areas. In northeastern Estonia, local lenses of the Oru Member (the earliest Upper Vendian sedimentary rocks in Estonia resembling the debris of weathered crystalline rocks yield accessory zircon which in a 1-2 m thick layer above the basement surface is similar to the zircons of the underlying weathering mantle of certain crystalline rocks. In the next unit, the Moldova Member, up to 43 m above the basement surface, a mixture of zircons resembling those of various local basement rocks has been found. Further upwards, in the Vendian and Lower

  11. Sedimentary Micro-phase Automatic Recognition Based on BP Neural Network

    Institute of Scientific and Technical Information of China (English)

    龚声蓉; 王朝晖


    In the process of geologic prospecting and development, it is important to forecast the distribution of gritstone, master the regulation of physical parameter in the reserves mass level. Especially, it is more important to recognize to rock phase and sedimentary circumstance. In the land level, the study of sedimentary phase and micro-phase is important to prospect and develop. In this paper, an automatic approach based on ANN (Artificial Neural Networks) is proposed to recognize sedimentary phase, the corresponding system is designed after the character of well general curves is considered. Different from the approach extracting feature parameters, the proposed approach can directly process the input curves. The proposed method consists of two steps: The first step is called learning. In this step, the system creates automatically sedimentary micro-phase features by learning from the standard sedimentary micro-phase patterns such as standard electric current phase curves of the well and standard resistance rate curves of the well. The second step is called recognition. In this step, based the results of the learning step, the system classifies automatically by comparing the standard pattern curves of the well to unknown pattern curves of the well. The experiment has demonstrated that the proposed approach is more effective than those approaches used previously.

  12. Modelling of reactive transport in a sedimentary basin affected by a glaciation/deglaciation event

    Energy Technology Data Exchange (ETDEWEB)

    Bea, S.A.; Mayer, U. [Univ. of British Columbia, Dept. of Earth and Ocean Sciences, Vancouver, BC (Canada); MacQuarrie, K.T.B. [Univ. of New Brunswick, Dept. of Civil Engineering, Fredericton, NB (Canada)


    Canada's plan for the long-term care of used nuclear fuel is containment and isolation in a Deep Geologic Repository (DGR) constructed in a suitable sedimentary or crystalline rock formation. In sedimentary basins fluid migration and geochemical conditions may be impacted by multiple interacting processes including density-dependent groundwater flow, solute transport, heat transfer, mechanical loading, and rock-water interactions. Understanding the interactions among these processes is important when assessing the long-term hydrodynamic and geochemical stability of sedimentary basins during glaciation/deglaciation events. To improve the capability to investigate these processes, an enhanced version of the reactive transport code MIN3P (i.e. MIN3P-NWMO) was developed and tested. The processes incorporated in the new model were evaluated by simulating reactive transport in a hypothetical sedimentary basin affected by a simplified glaciation scenario consisting of a single cycle of ice sheet advance and retreat. The simulations are used to provide an illustrative assessment of the hydrogeological and geochemical stability of this sedimentary basin over a time period of 32,500 years. The results suggest a high degree of geochemical stability. (author)

  13. Sedimentary characteristics of tide-dominated estuary in Donghetang Formation(Upper Devonian), central Tarim Basin

    Institute of Scientific and Technical Information of China (English)


    The Donghetang Formation (Upper Devonian) in central Tarim Basin has been thought an important oil and gas reservoir since the abundant oil and gas resources were found in the wells W16, W20, W34, and other fields. However, the sedimentary environment of the Donghetang Formation has been disputed because it suffered from both tidal and fluvial actions and there were not rich fossils in the sandstone. After the authors analyzed sedimentary features by means of drill cores, well logging data, paleosols, and with SEM obseruations, three kinds of sedimentary environments were distinguished: alluvial fan, tide-dominated estuary, and shelf. Particularly, the sedimentary features of tide-dominated estuary were studied in detail. Besides, the authors discussed sedimentary characteristics of the Donghetang Formation which was divided into two fourth-order sequences and five system tracts. At the same time, according to the forming process of five system tracts, the whole vertical evolution and lateral transition of tide-dominated estuary were illustrated clearly. Finally, the reservoir quality was evaluated based on porosity and permeability.

  14. In-situ Detection of Squalane in Sedimentary Organic Matter Using Monoclonal Antibodies (United States)

    Bailey, J. V.; Corsetti, F. A.; Moldowan, J. M.; Fago, F.; Caron, D.


    Sedimentary geolipids can serve as powerful tools for reconstructing ancient ecosystems, but only if investigators can demonstrate that the hydrocarbons are indigenous to their host rocks. The association of molecules with primary sedimentary fabrics could indicate a syngenetic relationship. However, traditional biomarker analyses require extraction from large quantities of powdered rock, confounding detailed spatial correlations. Biological studies commonly use antibodies as extremely sensitive molecular probes. When coupled with fluorescent labels, antibodies allow for the visual localization of molecules. Here we show that monoclonal antibodies that bind specifically to geolipid compounds can be used for in situ detection and labeling of such compounds in mineral-bound organic macerals. Monoclonal antibodies to squalene, produced for human health studies, also react with the geolipid, squalane. We show that squalene antibodies do not react with other common sedimentary hydrocarbons. We also show that squalane antibodies bind specifically to isolated organic-rich lamina in Eocene-age, squalane-containing rocks. These results suggest that squalane is confined to discrete organo-sedimentary fabrics within those rocks, providing evidence for its syngeneity. The chemical similarity of squalane to other sedimentary hydrocarbons hints at the potential for developing monoclonal antibodies to a variety of biomarkers that could then be localized in rocks, sediments, and extant cells.

  15. Rheumatoid Arthritis Educational Video Series (United States)

    ... Corner / Patient Webcasts / Rheumatoid Arthritis Educational Video Series Rheumatoid Arthritis Educational Video Series This series of five videos ... Your Arthritis Managing Chronic Pain and Depression in Arthritis Nutrition & Rheumatoid Arthritis Arthritis and Health-related Quality of Life ...

  16. Applied time series analysis

    CERN Document Server

    Woodward, Wayne A; Elliott, Alan C


    ""There is scarcely a standard technique that the reader will find left out … this book is highly recommended for those requiring a ready introduction to applicable methods in time series and serves as a useful resource for pedagogical purposes.""-International Statistical Review (2014), 82""Current time series theory for practice is well summarized in this book.""-Emmanuel Parzen, Texas A&M University""What an extraordinary range of topics covered, all very insightfully. I like [the authors'] innovations very much, such as the AR factor table.""-David Findley, U.S. Census Bureau (retired)""…

  17. Time series analysis

    CERN Document Server

    Madsen, Henrik


    ""In this book the author gives a detailed account of estimation, identification methodologies for univariate and multivariate stationary time-series models. The interesting aspect of this introductory book is that it contains several real data sets and the author made an effort to explain and motivate the methodology with real data. … this introductory book will be interesting and useful not only to undergraduate students in the UK universities but also to statisticians who are keen to learn time-series techniques and keen to apply them. I have no hesitation in recommending the book.""-Journa

  18. Research on 3D Distribution of Meandering River Sand Body Using Sedimentary Facies Method and 3D Geological Modeling

    Institute of Scientific and Technical Information of China (English)

    WU Jian; CAO Dai-yong


    Sedimentary facies study is an important method in describing the property and distribution of reservoir. 3D geological modeling is a powerful tool in 3D characterization of geological bodies. By combining the sedimentary facies study with 3D geological modeling to generate 3D sedimentary facies model, the 3D geometry and distribution feature of sand bodies can be more accurately characterized, particularly in 3D view. In Liuchu oilfield of Jizhong depression, the Ed2IV formation was recognized as meandering river deposition facies and five sedimentary facies were identified, which include point bar sand, levee, channel margin, abandoned channel and floodplain. All the 24 sand body facies in Ed2IV were mapped and the 3D sedimentary facies model established based on 2D facies maps. The result shows that the 3D sedimentary facies model is well matched for the research result of sedimentary facies. Being an extension of traditional sedimentary study, the 3D sedimentary facies model can be used to describe the 3D geometry and distribution orders of a single sand body more reliably and more accurately.

  19. Eutrophication signals in the sedimentary record of dinoflagellate cysts in coastal waters (United States)

    Dale, Barrie


    A brief review is presented of the current status of eutrophication signals from the sedimentary records of dinoflagellate cysts in coastal waters, particularly of NW Europe. There is a dearth of the multi-decadal time series data from plankton needed to document eutrophication, and the cysts may provide an alternative source of information. Two different eutrophication signals have been described so far from cyst records: 1) from the Oslofjord, comprising a marked increase in total cyst concentrations (interpreted as probably reflecting increased phytoplankton productivity), with Lingulodinium polyedrum cysts accounting for most of the increase (interpreted as a species particularly benefiting from added nutrients from cultural eutrophication in late summer when nutrients otherwise may be limiting); and 2) the heterotroph signal, from several other Norwegian fjords and Tokyo Bay, Japan, involving both cases of increased cyst concentrations and others with no particular increase, but with a marked proportional increase in cysts of heterotrophic species (interpreted as reflecting increased diatoms and possibly other prey for the heterotrophic dinoflagellates and/or more unfavourable conditions for autotrophs, e.g. from shading). These signals should be used critically, and there is a particular need to distinguish between eutrophication signals and climate signals that may be co-occurring at a given time. Work by various authors has generally supported the concept of these cyst-based signals since they were first published, including both further records from cored sediments from other parts of the world and studies relating cyst distributions in surface sediments to gradients of pollution and nutrients from sewage discharge. Recent, unpublished work by Dale and Sætre, linked cyst signals in cored sediments to the timing of collapse of local fisheries at different times within the past fifty years in four fjord systems along the Norwegian Skagerrak coast

  20. Geochemistry and diagenesis of Miocene lacustrine siliceous sedimentary and pyroclastic rocks, Mytilinii basin, Samos Island, Greece (United States)

    Stamatakis, M.G.; Hein, J.R.; Magganas, A.C.


    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 sedimentary 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

  1. Sedimentary environments of organic matter from Middle Permian source rocks in northern Xinjiang,China

    Institute of Scientific and Technical Information of China (English)

    MIAO Jianyu; KOU Hansheng; ZHOU Lifa; HAN Zhongyuan


    A systematic analysis of the inorganic and organic geochemistry of Middle Permian source rocks comprising carbonate rocks and mudstones was carried out, with samples collected from the outcrop and bore of the Junggar, Turpan and Ili basins in northern Xinjiang. This study confirmed that sedimentary parameters for an ancient water body, such as inorganic geochemistry and paleosalinity, have a close relation to the organic matter of source rocks. It is also disclosed that phytane predominance in the source rocks is mainly due to a reducing environment. Biomarkers, such as gammacerane and β-carotene, in the samples reflect a specific salinity in the sedimentary environments. Sedimentary zones with a strong reducing environment are more likely to produce deposits of primary organic matter, which will be buried and preserved contemporarily. Consequently, the source rocks are generally high in organic content and better in organic type than ordinary ones, and vice versa.

  2. Sedimentary basin analysis using airborne gravity data: a case study from the Bohai Bay Basin, China (United States)

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


    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.

  3. Sedimentary Mounds on Mars: Tracing Present-day Formation Processes into the Past (United States)

    Niles, P. B.; Michalski, J.; Edwards, C. S.


    High resolution photography and spectroscopy of the martian surface (MOC, HiRISE) from orbit has revolutionized our view of Mars with one and revealed spectacular views of finely layered sedimentary materials throughout the globe [1]. Some of these sedimentary deposits are 'mound' shaped and lie inside of craters (Fig 1). Crater mound deposits are found throughout the equatorial region, as well as ice-rich deposits found in craters in the north and south polar region [2-4]. Despite their wide geographical extent and varying volatile content, the 'mound' deposits have a large number of geomorphic and structural similarities that suggest they formed via equivalent processes. Thus, modern depositional processes of ice and dust can serve as an invaluable analog for interpreting the genesis of ancient sedimentary mound deposits.

  4. Ecosystem disturbances in Central European spruce forests: a multi-proxy integration of dendroecology and sedimentary records (United States)

    Clear, Jennifer; Chiverrell, Richard; Kunes, Petr; Svoboda, Miroslav; Boyle, John


    Disturbance dynamics in forest ecosystems shows signs of perturbation in the light of changing climate regimes with the frequency and intensity of events (e.g. pathogens in North America and Central Europe) amplified, becoming more frequent and severe. The montane Norway spruce (Picea abies) dominated forests of Central Europe are a niche habitat and environment; situated outside their natural boreal distribution (e.g. Fenno-Scandinavia). These communities are at or near their ecological limits and are vulnerable to both short term disturbances (e.g. fire, windstorm and pathogens) and longer-term environmental change (e.g. climate induced stress and changing disturbance patterns). Researches have linked negative impacts on spruce forest with both wind disturbance (wind-throw) and outbreaks of spruce bark beetle (Ips typographus), and there is growing evidence for co-association with wind damage enhancing pathogenic outbreaks. Examples include: in the Bohemian Forest (Czech Republic) the mid-1990s spruce bark beetle outbreak and the 2007 windstorm and subsequent bark beetle outbreak. In the High Tatra Mountains (Slovakia) there is a further co-association of forest disturbance with windstorms (2004 and 2014) and an ongoing bark beetle outbreak. The scale and severity of these recent outbreaks of spruce bark beetle are unprecedented in the historical forest records. Here, findings from ongoing research developing and integrating data from dendroecological, sedimentary palaeoecological and geochemical time series to develop a longer-term perspective on forest dynamics in these regions. Tree-ring series from plots or forest stands (>500) are used alongside lake (5) and forest hollow (3) sediments from the Czech and Slovak Republics to explore the local, regional and biogeographical scale of forest disturbances. Dendroecological data showing tree-ring gap recruitment and post-suppression growth release highlight frequent disturbance events focused on tree or forest

  5. Composition: Unity - Diversity series

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl


    Unity-Diversity series are open compositions to be realised by improvising musicians. See more about my composition practise in the entry "Composition - General Introduction". This work is licensed under a Creative Commons "by-nc" License. You may for non-commercial purposes use and distribute it...

  6. Discrimination. Opposing Viewpoints Series. (United States)

    Williams, Mary E., Ed.

    Books in the Opposing Viewpoints series challenge readers to question their own opinions and assumptions. By reading carefully balanced views, readers confront new ideas on the topic of interest. The Civil Rights Act of 1964, which prohibited job discrimination based on age, race, religion, gender, or national origin, provided the groundwork for…

  7. Visual time series analysis

    DEFF Research Database (Denmark)

    Fischer, Paul; Hilbert, Astrid


    commands, our application is select-and-click-driven. It allows to derive many different sequences of deviations for a given time series and to visualize them in different ways in order to judge their expressive power and to reuse the procedure found. For many transformations or model-ts, the user may...

  8. Parent's Journal. [Videotape Series]. (United States)


    Parent's Journal is a set of 16 videotapes for parents of prenatal, infant, and toddler-age children, created by the Alaska Native Home Base Video Project of the Tlingit and Haida Head Start Program. This series offers culturally relevant solutions to the challenges of parenting, drawing on the life stories and experiences of capable mothers and…

  9. Family Feathers. [Videotape Series]. (United States)


    Family Feathers is a set of 18 videotapes for parents of preschool children, created by the Alaska Native Home Base Video Project of the Tlingit and Haida Head Start Program. This series offers culturally relevant solutions to the challenges of parenting, drawing on practical advice from Tlingit and Haida parents, wisdom from elders, and some of…

  10. Little Herder Reading Series. (United States)

    Bureau of Indian Affairs (Dept. of Interior), Washington, DC.

    The Little Herder Reading Series is comprised of 4 volumes based on the life of a Navajo Indian girl. The books are written in English blank verse and describe many facets of Indian life. The volumes contain illustrations by Hoke Denetsosie which give a pictorial representation of the printed verse. The reading level is for the middle and upper…

  11. Characteristics of the Middle-Late Triassic sedimentary facies assemblages in the Songpan-Ruoergai area

    Institute of Scientific and Technical Information of China (English)

    YAN Zhen; YU Liangjun; LI Jiliang; BIAN Qiantao; WANG Zongqi; YANG Yongcheng


    The Middle-Late Triassic sedimentary rocks in the Songpan-Ruoergai area mainly consist of calcareous siltstone, muddy limestone, lithic arkose, feldspathic litharenite, mudstone, wormkalk, oolithic limestone, and conglomerate. Except for limestone bed increasing eastward longitudinally and vertically, the calcareous component of the sandstones increases obviously. Abundant benthic and plant fossils and their clasts occur within these rocks. The sedimentary structures predominately contain flaser, parallel, tabular, wavy,and herringbone cross beddings. These data coevally imply that the Middle-Late Triassic sediments deposited in the fluvial, lake and tide environments. Additionally, the rocks display graded, parallel, hummocky beddings, and sandy lamination, a feature characteristic of storm deposits.


    Institute of Scientific and Technical Information of China (English)


    Some polar coordinates are used to determine the domain and the ball of convergence of a multiple Taylor series. In this domain and in this ball the series converges,converges absolutely and converges uniformly on any compact set. Growth and other properties of the series may also be studied. For some random multiple Taylor series there are some corresponding properties.

  13. Aliphatic biomarkers and their signal from two hydrogeochemically differing sedimentary environments of the Tertiary Krepoljin Coal Basin (Serbia) (United States)

    Dević, Gordana J.; Popovic, Zoran


    The sediments of the coal-bearing series of the Tertiary Krepoljin Brown Coal Basin have been investigated and presented in this manuscript. The samples of the intercalated mixed sediments (pieces of coal in clays, sandstones and shales) originate from two hydrogeochemically differing sedimentary environments: the illite-montmorillonitic (IM), and the calcitic (Ct) environment. The characteristics of the early diagenetic processes which influenced the composition of the organic matter of this sediment were assessed by the statistical correlation analysis and multivariate principal component analysis. The precursor material of higher plants gymnosperms had a significant influence on the overall organic matter of mixed sediments in both hydrochemical environments. A weak effect of N/C ratios on the specific diagenetic transformations of hopanoid molecules is noticed in the samples of the calcite environment. Sterane maturation transformations are not marked as significant for the samples of mixed sediments by the component analysis. The samples of I-M environments show a strong inhibitory effect on the processes of diastereoisomerization.

  14. The stable hydrogen isotopic composition of sedimentary plant waxes as quantitative proxy for rainfall in the West African Sahel (United States)

    Niedermeyer, Eva M.; Forrest, Matthew; Beckmann, Britta; Sessions, Alex L.; Mulch, Andreas; Schefuß, Enno


    Various studies have demonstrated that the stable hydrogen isotopic composition (δD) of terrestrial leaf waxes tracks that of precipitation (δDprecip) both spatially across climate gradients and over a range of different timescales. Yet, reconstructed estimates of δDprecip and corresponding rainfall typically remain largely qualitative, due mainly to uncertainties in plant ecosystem net fractionation, relative humidity, and the stability of the amount effect through time. Here we present δD values of the C31n-alkane (δDwax) from a marine sediment core offshore the Northwest (NW) African Sahel covering the past 100 years and overlapping with the instrumental record of rainfall. We use this record to investigate whether accurate, quantitative estimates of past rainfall can be derived from our δDwax time series. We infer the composition of vegetation (C3/C4) within the continental catchment area by analysis of the stable carbon isotopic composition of the same compounds (δ13Cwax), calculated a net ecosystem fractionation factor, and corrected the δDwax time series accordingly to derive δDprecip. Using the present-day relationship between δDprecip and the amount of precipitation in the tropics, we derive quantitative estimates of past precipitation amounts. Our data show that (a) vegetation composition can be inferred from δ13Cwax, (b) the calculated net ecosystem fractionation represents a reasonable estimate, and (c) estimated total amounts of rainfall based on δDwax correspond to instrumental records of rainfall. Our study has important implications for future studies aiming to reconstruct rainfall based on δDwax; the combined data presented here demonstrate that it is feasible to infer absolute rainfall amounts from sedimentary δDwax in tandem with δ13Cwax in specific depositional settings.

  15. Series elastic actuators (United States)

    Williamson, Matthew M.


    This thesis presents the design, construction, control and evaluation of a novel for controlled actuator. Traditional force controlled actuators are designed from the premise that 'Stiffer is better'. This approach gives a high bandwidth system, prone to problems of contact instability, noise, and low power density. The actuator presented in this thesis is designed from the premise that 'Stiffness isn't everything'. The actuator, which incorporates a series elastic element, trades off achievable bandwidth for gains in stable, low noise force control, and protection against shock loads. This thesis reviews related work in robot force control, presents theoretical descriptions of the control and expected performance from a series elastic actuator, and describes the design of a test actuator constructed to gather performance data. Finally the performance of the system is evaluated by comparing the performance data to theoretical predictions.

  16. Causality between time series

    CERN Document Server

    Liang, X San


    Given two time series, can one tell, in a rigorous and quantitative way, the cause and effect between them? Based on a recently rigorized physical notion namely information flow, we arrive at a concise formula and give this challenging question, which is of wide concern in different disciplines, a positive answer. Here causality is measured by the time rate of change of information flowing from one series, say, X2, to another, X1. The measure is asymmetric between the two parties and, particularly, if the process underlying X1 does not depend on X2, then the resulting causality from X2 to X1 vanishes. The formula is tight in form, involving only the commonly used statistics, sample covariances. It has been validated with touchstone series purportedly generated with one-way causality. It has also been applied to the investigation of real world problems; an example presented here is the cause-effect relation between two climate modes, El Ni\\~no and Indian Ocean Dipole, which have been linked to the hazards in f...

  17. Perturbation induced changes in substrate use by the blue mussel, Mytilus edulis, in sedimentary systems

    NARCIS (Netherlands)

    Kangeri, A.K.; Jansen, J.M.; Barkman, B.R.; Donker, J.J.A.; Joppe, D.J.; Dankers, N.M.J.A.


    For sessile benthic marine organisms adhesion to a stable substrate is important for survival. Sedimentary systems, however, generally lack stable surfaces. How sessile species like the mussel, Mytilus edulis, are able to achieve stability in unstable sediments is not fully understood. An intertidal

  18. Pertubation induced changes in substrate use by the blue mussel, Mytilus edulis, in sedimentary systems

    NARCIS (Netherlands)

    wa Kangeri, A.K.; Jansen, J.M.; Barkman, B.R.; Donker, J. J. A.; Joppe, D.J.; Dankers, N.M.J.A.


    For sessile benthic marine organisms adhesion to a stable substrate is important for survival. Sedimentary systems, however, generally lack stable surfaces. How sessile species like the mussel, Mytilus edulis, are able to achieve stability in unstable sediments is not fully understood. An intertidal


    Institute of Scientific and Technical Information of China (English)

    JinKuili; LiuDameng; XiaoXianming


    According to the study on the oil-gas source rocks in China for ten years,in connection with the microscopic, submicroscopic levels, the authors used the microscope photometry together with transmission electronic microscopy, scanning electronic microscopy and proposed a new classification for Sedimentary organic matters.

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

    Digital Repository Service at National Institute of Oceanography (India)

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

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

  1. Composition and sources of sedimentary organic matter in the deep Eastern Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    R. Pedrosa-Pàmies


    Full Text Available Surface sediments collected from deep slopes and basins (1018–4087 m depth of the oligotrophic Eastern Mediterranean Sea have been analysed for bulk elemental and isotopic composition of organic carbon, total nitrogen and selected lipid biomarkers, jointly with grain size distribution and other geochemical proxies. The distribution and sources of sedimentary organic matter (OM have been subsequently assessed and general environmental variables, such as water depth and currents, have been examined as causative factors of deep-sea sediment characteristics. Lithogenic and biogenic carbonates are the dominant sedimentary fractions, while both bulk and molecular organic tracers reflect a mixed contribution from autochthonous and allochthonous sources for the sedimentary OM, as indicated by relatively degraded marine OM, terrestrial plant waxes and anthropogenic OM including degraded petroleum by-products, respectively. Wide regional variations have been observed amongst the studied proxies, which reflect the multiple factors controlling sedimentation in the deep Eastern Mediterranean Sea. Our findings highlight the role of deep Eastern Mediterranean basins as depocentres of organic-rich fine-grained sediments (mean 5.4 ± 2.4 μm, with OM accumulation and burial due to aggregation mechanisms and hydrodynamic sorting. A multi-proxy approach is hired to investigate the biogeochemical composition of sediment samples, which sheds new light on the sources and transport mechanisms along with the impact of preservation vs. diagenetic processes on the composition of sedimentary OM in the deep basins of the oligotrophic Eastern Mediterranean Sea.

  2. Sedimentary cycles in coal and evaporite basins and the reconstruction of Paleozoic climate

    NARCIS (Netherlands)

    van den Belt, F.J.G.


    This thesis deals with large-scale processes controlling the formation of sedimentary cycles in coal and evaporite basins and their relation to large-scale fluctuations of Palaeozoic climate. Coal-clastic cycles dominate Pennsylvanian sequences in palaeo-equatorial basins from Euramerica. They forme

  3. Norway and adjacent sedimentary basins during Cenozoic times - sediment fluxes, accumulation rates and mass balance

    DEFF Research Database (Denmark)

    Gołędowski, Bartosz; Nielsen, S.B.; Clausen, O.R.


    use offshore data from adjacent sedimentary basins (the North Sea and the Norwegian shelf) to calculate the amount of erosion. We have used a broad dataset of seismic 2D lines to map depositional units and a well dataset for the stratigraphic control and the velocity distribution in the sediments. We...

  4. Seismic stratigraphy and sedimentary architecture of the Chalk Group in south-west Denmark

    DEFF Research Database (Denmark)

    Larsen, Connie; Ineson, Jon; Boldreel, Lars Ole


    The article focuses on a study undertaken by the Chalk Group on the western onshore region of the Danish Basin in Eastern Denmark related on the seismic stratigraphy and sedimentary architecture of the region. The study is undertaken through subdividing the northern North German Basin and the south...

  5. Understanding the subsurface thermal structure of deep sedimentary basins in Denmark - measurements and modelling results

    DEFF Research Database (Denmark)

    Balling, N.; Poulsen, Søren Erbs; Bording, Thue Sylvester


    Most of the Danish area is characterized by deep sedimentary basins with a great potential for exploitation of geothermal energy. Geothermal reservoirs are present at various depths and temperatures. Currently, three geothermal plants are operating producing warm water for district heating purposes...

  6. Ferroan dolomite cement in Cambrian sandstones: burial history and hydrocarbon generation of the Baltic sedimentary basin

    DEFF Research Database (Denmark)

    Sliaupa, S.; Cyziene, J.; Molenaar, Nicolaas


    The conditions and timing of carbonate cementation in Cambrian sandstones of the Baltic sedimentary basin were determined by oxygen and carbon stable isotope and chemical data in combination with optical and cathodoluminescence petrographic studies. Studied samples represent a range in present...

  7. From ooze to sedimentary rock, the first diagenetic processes affecting the chalk of eastern Denmark

    DEFF Research Database (Denmark)

    Moreau, Julien; Boussaha, Myriam; Nielsen, Lars

    The Stevns peninsula, situated in the eastern Danish Basin at the fringe of the Baltic Sea, is an ideal target for studying the early stages of diagenesis that affected the Upper Cretaceous chalk during its burial to 500-1400m depth. For the present study onshore and offshore high-resolution seis...... in chalk sedimentary rocks....

  8. Stratified precambrian rocks (sedimentary ) beneath the midcontinent region of the US

    Energy Technology Data Exchange (ETDEWEB)

    Hauser, E.C.


    A thick sequence of layered rocks occurs beneath the Phanerozoic platform strata which blanket the US midcontinent. Observed on COCORP deep reflection data in southern Illinois and Indiana and in SW Oklahoma and adjacent Texas, this sequence is locally 1--3 times as thick as the overlying Paleozoic cover, but the origin of this sequence and its ultimate lateral extent are unknown. However, the occurrences of Precambrian layered rocks on both the COCORP profiles and reprocessed industry seismic reflection data from the region lie within regions of generally low amplitude and low frequency aeromagnetic anomaly, suggesting an even greater distribution. Unmetamorphosed Precambrian sedimentary rocks have been recovered from drill holes in southwest Ohio and adjacent northern Kentucky and southwesternmost Indiana. These Precambrian sedimentary rocks lie above and may be part of an underlying package of strongly layered rocks imaged on a short and shallow seismic profile in southwest Ohio. These Precambrian sedimentary rocks were originally viewed as part of a late Precambrian (Keweenawan ) rift; however, in light of Grenville foreland structures seen on the COCORP profile to the north in west central Ohio, these Precambrian strata may (1) be part of a heretofore unrecognized Grenville foreland basin, or (2) indicate that unmetamorphosed Precambrian sedimentary material may be an important constituent of the layered rocks observed on COCORP beneath southern Illinois and Indiana.

  9. Stratified precambrian rocks (sedimentary?) beneath the midcontinent region of the US. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Hauser, E.C.


    A thick sequence of layered rocks occurs beneath the Phanerozoic platform strata which blanket the US midcontinent. Observed on COCORP deep reflection data in southern Illinois and Indiana and in SW Oklahoma and adjacent Texas, this sequence is locally 1--3 times as thick as the overlying Paleozoic cover, but the origin of this sequence and its ultimate lateral extent are unknown. However, the occurrences of Precambrian layered rocks on both the COCORP profiles and reprocessed industry seismic reflection data from the region lie within regions of generally low amplitude and low frequency aeromagnetic anomaly, suggesting an even greater distribution. Unmetamorphosed Precambrian sedimentary rocks have been recovered from drill holes in southwest Ohio and adjacent northern Kentucky and southwesternmost Indiana. These Precambrian sedimentary rocks lie above and may be part of an underlying package of strongly layered rocks imaged on a short and shallow seismic profile in southwest Ohio. These Precambrian sedimentary rocks were originally viewed as part of a late Precambrian (Keweenawan?) rift; however, in light of Grenville foreland structures seen on the COCORP profile to the north in west central Ohio, these Precambrian strata may (1) be part of a heretofore unrecognized Grenville foreland basin, or (2) indicate that unmetamorphosed Precambrian sedimentary material may be an important constituent of the layered rocks observed on COCORP beneath southern Illinois and Indiana.

  10. The Potassic Sedimentary Rocks in Gale Crater, Mars, as Seen by ChemCam Onboard Curiosity. (United States)

    Le Deit, Laetitia; Mangold, Nicolas; Forni, Olivier; Cousin, Agnes; Lasue, Jeremie; Schröder, Susanne; Wiens, Roger C.; Sumner, Dawn Y.; Fabre, Cecile; Stack, Katherine M.; Anderson, Ryan; Blaney, Diana L.; Clegg, Samuel M.; Dromart, Gilles; Fisk, Martin; Gasnault, Olivier; Grotzinger, John P.; Gupta, Sanjeev; Lanza, Nina; Le Mouélic, Stephane; Maurice, Sylvestre; McLennan, Scott M.; Meslin, Pierre-Yves; Nachon, Marion; Newsom, Horton E.; Payre, Valerie; Rapin, William; Rice, Melissa; Sautter, Violaine; Treiman, Alan H.


    The Mars Science Laboratory rover Curiosity encountered potassium-rich clastic sedimentary rocks at two sites in Gale Crater, the waypoints Cooperstown and Kimberley. These rocks include several distinct meters-thick sedimentary outcrops ranging from fine sandstone to conglomerate, interpreted to record an ancient fluvial or fluvio-deltaic depositional system (Grotzinger et al., 2015). From ChemCam LIBS chemical analyses, this suite of sedimentary rocks has an overall mean K2O abundance that is more than five times higher than that of the average Martian crust. The combined analysis of ChemCam data with stratigraphic and geographic locations reveals that the mean K2O abundance increases upward through the stratigraphic section. Chemical analyses across each unit can be represented as mixtures of several distinct chemical components, i.e. mineral phases, including K-bearing minerals, mafic silicates, Fe-oxides, and Fe-hydroxide/oxyhydroxides. Possible K-bearing minerals include alkali feldspar (including anorthoclase and sanidine) and K-bearing phyllosilicate such as illite. Mixtures of different source rocks, including a potassium-rich rock located on the rim and walls of Gale Crater are the likely origin of observed chemical variations within each unit. Physical sorting may have also played a role in the enrichment in K in the Kimberley formation. The occurrence of these potassic sedimentary rocks provides additional evidence for the chemical diversity of the crust exposed at Gale Crater.


    Directory of Open Access Journals (Sweden)

    Josip Crnički


    Full Text Available The main features of the geochemistry of rare earth elements (REE, REE mineralogy and the REE i contents and distributions in sedimentary rocks are presented. A new classification of REE minerals as well as a new systematic order of the REE behaviour in sedimentology is introduced and explained.

  12. A New Unusual Ice-induced Sedimentary Structure: the Silt Mushroom. (United States)

    Jianhua, Zhong; Liangtian, Ni; Ningliang, Sun; Chuang, Liu; Bing, Hao; Mengchun, Cao; Xin, Chen; Ke, Luo; Shengxin, Liu; Leitong, Huang; Guanqun, Yang; Shaojie, Wang; Feifei, Su; Xuejing, He; Yanqiu, Xue


    Upon channel bars or point bars within the lows of the Yellow River, a new sedimentary structure, named 'silt mushroom', has been observed. The process of their formation is interpreted to be via the ice process. The name, the silt mushroom comes from their figurative form. This is because they look somewhat similar to mushroom's in size and shape; being in the range of 1 to 10 cm in diameter, with the medium 3-5 cm, and on average 10 cm in height, occuring generally in groups, and occasionally in isolation in relatively soft silt. They develop in the transition from winter to spring, and are convincingly related to ice processes. Ice-induced silt mushrooms are best examined in association with the many other newly discovered ice-induced sedimentary structures (over 20 kinds). Clearly, up to now, ice processes have been significantly underestimated. With the substantial discovery of the ice-induced silt mushroom, it opens up new questions. This is because its structure mirrors the same sedimentary structures found in rocks, questioning their genesis, and sedimentary environment analysis. This achievement is significant not only in sedimentology, but also in palaeogeography, palaeoclimate, geological engineering, hydraulics and fluviology.

  13. Elemental geochemistry of sedimentary rocks at Yellowknife Bay, Gale crater, Mars

    NARCIS (Netherlands)

    McLennan, S.M.; Anderson, R.B.; Bell III, J.F.; Bridges, J.C.; Calef III, F.; Campbell, J.L.; Clark, B.C.; Clegg, S.; Conrad, P.; Cousin, A.; Des Marais, D.J.; Dromart, G.; Dyar, M.D.; Edgar, L.A.; Ehlmann, B.L.; Fabre, C.; Forni, O.; Gasnault, O.; Gellert, R.; Gordon, S.; Grant, J.A.; Grotzinger, J.P.; Gupta, S.; Herkenhoff, K.E.; Hurowitz, J.A.; King, P.L.; Mouélic, S.L.; Leshin, L.A.; Léveillé, R.; Lewis, K.W.; Mangold, N.; Maurice, S.; Ming, D.W.; Morris, R.V.; Nachon, M.; Newsom, H.E.; Ollila, A.M.; Perrett, G.M.; Rice, M.S.; Schmidt, M.E.; Schwenzer, S.P.; Stack, K.; Stolper, E.M.; Sumner, D.Y.; Treiman, A.H.; VanBommel, S.; Vaniman, D.T.; Vasavada, A.; Wiens, R.C.; Yingst, R.A.; ten Kate, Inge Loes


    Sedimentary rocks examined by the Curiosity rover at Yellowknife Bay, Mars, were derived from sources that evolved from an approximately average martian crustal composition to one influenced by alkaline basalts. No evidence of chemical weathering is preserved, indicating arid, possibly cold, paleocl

  14. The depositional environment of Jurassic organic-rich sedimentary rocks in NW Europe : a biomarker approach

    NARCIS (Netherlands)

    Kaam-Peters, H.M.E.


    Information on the depositional environment of sediments and sedimentary rocks can be obtained in several ways, using e.g. sedimentological, palynological or (micro)palaeontological approaches. In this thesis, results are presented of molecular organic geochemical investigations, aimed at palaeoenvi

  15. The potassic sedimentary rocks in Gale Crater, Mars, as seen by ChemCam Onboard Curiosity (United States)

    Le Deit, Laetitia; Mangold, Nicolas; Forni, Olivier; Cousin, Agnes; Lasue, Jeremie; Schröder, Susanne; Wiens, Roger C.; Sumner, Dawn Y.; Fabre, Cecile; Stack, Katherine M.; Anderson, Ryan; Blaney, Diana L.; Clegg, Samuel M.; Dromart, Gilles; Fisk, Martin; Gasnault, Olivier; Grotzinger, John P.; Gupta, Sanjeev; Lanza, Nina; Le Mouélic, Stephane; Maurice, Sylvestre; McLennan, Scott M.; Meslin, Pierre-Yves; Nachon, Marion; Newsom, Horton E.; Payre, Valerie; Rapin, William; Rice, Melissa; Sautter, Violaine; Treiman, Alan H.


    The Mars Science Laboratory rover Curiosity encountered potassium-rich clastic sedimentary rocks at two sites in Gale Crater, the waypoints Cooperstown and Kimberley. These rocks include several distinct meters thick sedimentary outcrops ranging from fine sandstone to conglomerate, interpreted to record an ancient fluvial or fluvio-deltaic depositional system. From ChemCam Laser-Induced Breakdown Spectroscopy (LIBS) chemical analyses, this suite of sedimentary rocks has an overall mean K2O abundance that is more than 5 times higher than that of the average Martian crust. The combined analysis of ChemCam data with stratigraphic and geographic locations reveals that the mean K2O abundance increases upward through the stratigraphic section. Chemical analyses across each unit can be represented as mixtures of several distinct chemical components, i.e., mineral phases, including K-bearing minerals, mafic silicates, Fe-oxides, and Fe-hydroxide/oxyhydroxides. Possible K-bearing minerals include alkali feldspar (including anorthoclase and sanidine) and K-bearing phyllosilicate such as illite. Mixtures of different source rocks, including a potassium-rich rock located on the rim and walls of Gale Crater, are the likely origin of observed chemical variations within each unit. Physical sorting may have also played a role in the enrichment in K in the Kimberley formation. The occurrence of these potassic sedimentary rocks provides additional evidence for the chemical diversity of the crust exposed at Gale Crater.

  16. Phanerozoic growth of the epicontinental sedimentary reservoir: implications for long-term sea level change (United States)

    Husson, J. M.; Peters, S. E.


    Earth's sedimentary carapace contains the largest surface-accessible reservoir of biogeochemically sensitive elements and contains several times more water than all of the present-day ice caps and glaciers combined. It is, therefore, widely recognized that on timescales of ~1 Myr, one of the most important factors governing the evolution of many Earth systems is the exchange of materials into and out of the sedimentary shell. Although it is rarely assumed that these rates of exchange are invariant, it is generally presumed that the sedimentary reservoir as a whole behaves as a single large, slowly cycling system in which erosion and sediment storage are balanced; hence the expectation that there is no net change in sediment volume. Here, using the Macrostrat database, which consists of surface and subsurface data for 1,474 locations as well as more than 700K geologic map-based polygons, we show that the sedimentary reservoir is best conceived of as multiple reservoirs with different intrinsic cycling rates determined by tectonic and environmental contexts of deposition. We also show that the volume of sediment stored on presently subaerially exposed North America has increased markedly during the Phanerozoic. Initiation of growth in the size of this epicontinental sedimentary reservoir is well recorded by the Great Unconformity, which separates predominately Precambrian-aged, low porosity crystalline and metamorphic basement rocks from overlying, more porous Cambrian and younger sedimentary deposits. Geologic map-based data from Eurasia and Australia suggest similar overall patterns globally. Thus, after burial of the subaerially exposed Great Unconformity surface by Cambrian-Ordovician sediments, the groundwater storage capacity of the continents increased by more than 15 million cubic km (~1% of present ocean volume). Subsequent burial by younger sedimentary deposits further increased epicontinental groundwater storage capacity to the ~130 million cubic km it

  17. Modes of sedimentary basin formation in the north-eastern Black Sea (United States)

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


    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.

  18. Geoarchaeological investigations of a Mesolithic-Neolithic Sedimentary Sequence from Queens Sedgemoor, Somerset, UK (United States)

    Hill, Tom; Whittaker, John; Brunning, Richard; Law, Matthew; Bell, Martin; Wilkinson, Keith


    A geoarchaeological investigation was undertaken at Queens Sedgemoor in Somerset, southwest England, as part of the English Heritage funded project 'the Mesolithic wetland/dryland edge in Somerset' (EH 6624). This project was designed to address the National Heritage Protection Plan (Topic 4G) associated with the assessment of the character and significance of sedimentary and wetland archaeology. As part of the project, a sediment core extracted from the site and has undergone high resolution radiocarbon dating, with subsequent detailed and directed micropalaeontological analyses (pollen, diatom, foraminifera, ostracoda, mollusca) focussing on the sedimentary sequence associated with the Mesolithic and early Neolithic periods. The presentation summarises the results of this multiproxy analyses and explains how it has assisted in understanding the landscape during a period of substantial prehistoric importance in southwest England. The sedimentary sequence dates back to the Mesolithic period (7.6ky BP) and the microfossil evidence indicates hydroseral succession has taken place, with the initial establishment of a freshwater lake, prior to undergoing terrestrialisation and the eventual development of a raised bog. Holocene sea-level change also influenced the sedimentary archive. Due to a rise in relative sea level c. 6.7ky BP, subsequent coastal inundation and estuarine sedimentation took also place and is hereby associated with the Lower Wentlooge Formation of the Somerset Levels. Although poor pollen preservation was encountered within the section specifically associated with the Mesolithic-Neolithic transition, a clear picture of landscape change is presented for the sedimentary archive, with evidence indicative of landscape modification by humans since the late Mesolithic.

  19. Infinite sequences and series

    CERN Document Server

    Knopp, Konrad


    One of the finest expositors in the field of modern mathematics, Dr. Konrad Knopp here concentrates on a topic that is of particular interest to 20th-century mathematicians and students. He develops the theory of infinite sequences and series from its beginnings to a point where the reader will be in a position to investigate more advanced stages on his own. The foundations of the theory are therefore presented with special care, while the developmental aspects are limited by the scope and purpose of the book. All definitions are clearly stated; all theorems are proved with enough detail to ma

  20. Square summable power series

    CERN Document Server

    de Branges, Louis


    This text for advanced undergraduate and graduate students introduces Hilbert space and analytic function theory, which is centered around the invariant subspace concept. The book's principal feature is the extensive use of formal power series methods to obtain and sometimes reformulate results of analytic function theory. The presentation is elementary in that it requires little previous knowledge of analysis, but it is designed to lead students to an advanced level of performance. This is achieved chiefly through the use of problems, many of which were proposed by former students. The book's

  1. Introduction to Time Series Modeling

    CERN Document Server

    Kitagawa, Genshiro


    In time series modeling, the behavior of a certain phenomenon is expressed in relation to the past values of itself and other covariates. Since many important phenomena in statistical analysis are actually time series and the identification of conditional distribution of the phenomenon is an essential part of the statistical modeling, it is very important and useful to learn fundamental methods of time series modeling. Illustrating how to build models for time series using basic methods, "Introduction to Time Series Modeling" covers numerous time series models and the various tools f

  2. Fluvial geomorphic elements in modern sedimentary basins and their potential preservation in the rock record: A review (United States)

    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.


    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 (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 specific morphologic patterns. Tributary rivers tend to increase in size in the downstream direction. Because axial tributary rivers are present in confined settings in the sedimentary basin, they migrate back and forth within a relatively narrow belt (relative to the overall size of the sedimentary basin). Thus, axial tributary rivers tend to display amalgamated channel belt form with minimal preservation potential of floodplain deposits. Chute and neck cutoff avulsions are also common on meandering rivers in these settings. Where rivers on DFS exit their confining valley on the basin margin, sediment transport capacity is reduced and sediment deposition occurs resulting in development of a 'valley exit' nodal avulsion point that defines the DFS apex. Rivers may incise downstream of the basin margin valley because of changes in sediment supply and discharge through climatic variability or tectonic processes. We demonstrate that rivers on DFS commonly decrease in width down-DFS caused by infiltration

  3. Geoengineering Research for a Deep Underground Science and Engineering Laboratory in Sedimentary Rock (United States)

    Mauldon, M.


    A process to identify world-class research for a Deep Underground Science and Engineering Laboratory (DUSEL) in the USA has been initiated by NSF. While allowing physicists to study, inter alia, dark matter and dark energy, this laboratory will create unprecedented opportunities for biologists to study deep life, geoscientists to study crustal processes and geoengineers to study the behavior of rock, fluids and underground cavities at depth, on time scales of decades. A substantial portion of the nation's future infrastructure is likely to be sited underground because of energy costs, urban crowding and vulnerability of critical surface facilities. Economic and safe development of subsurface space will require an improved ability to engineer the geologic environment. Because of the prevalence of sedimentary rock in the upper continental crust, much of this subterranean infrastructure will be hosted in sedimentary rock. Sedimentary rocks are fundamentally anisotropic due to lithology and bedding, and to discontinuities ranging from microcracks to faults. Fractures, faults and bedding planes create structural defects and hydraulic pathways over a wide range of scales. Through experimentation, observation and monitoring in a sedimentary rock DUSEL, in conjunction with high performance computational models and visualization tools, we will explore the mechanical and hydraulic characteristics of layered rock. DUSEL will permit long-term experiments on 100 m blocks of rock in situ, accessed via peripheral tunnels. Rock volumes will be loaded to failure and monitored for post-peak behavior. The response of large rock bodies to stress relief-driven, time-dependent strain will be monitored over decades. Large block experiments will be aimed at measurement of fluid flow and particle/colloid transport, in situ mining (incl. mining with microbes), remediation technologies, fracture enhancement for resource extraction and large scale long-term rock mass response to induced

  4. Series overview and introduction. (United States)

    Alexander, Jeanne Leventhal; Dennerstein, Lorraine


    Studies and treatments for the symptomatic menopausal woman have been reviewed elsewhere. The aim of this clinical review series is to examine the evidence for the diagnosis and treatment of the woman who presents with distressing symptoms that she attributes to menopause, whose actual etiology may be a psychiatric disorder, a pre- or co-existing problem such as sleep or cognitive problems, or a dynamic interaction among one of these and a symptomatic menopause. This series of articles will review new research on somatic symptoms of depression, the depression continuum and its impact on morbidity and functioning, treatment issues related to remission of depression, cognitive decline or impairment secondary to a mood disorder, sleep problems in women and their impact on well-being and functioning, and attention and working memory problems in women. These will all be reviewed in the context of the vulnerable female patient and her experience of increased or new distressing symptoms during her menopausal transition. Recommendations for the diagnosis and management of women with psychiatric comorbidity and a symptomatic menopause are discussed.

  5. Uranium series, volcanic rocks (United States)

    Vazquez, Jorge A.


    Application of U-series dating to volcanic rocks provides unique and valuable information about the absolute timing of crystallization and differentiation of magmas prior to eruption. The 238U–230Th and 230Th-226Ra methods are the most commonly employed for dating the crystallization of mafic to silicic magmas that erupt at volcanoes. Dates derived from the U–Th and Ra–Th methods reflect crystallization because diffusion of these elements at magmatic temperatures is sluggish (Cherniak 2010) and diffusive re-equilibration is insignificant over the timescales (less than or equal to 10^5 years) typically associated with pre-eruptive storage of nearly all magma compositions (Cooper and Reid 2008). Other dating methods based on elements that diffuse rapidly at magmatic temperatures, such as the 40Ar/39Ar and (U–Th)/He methods, yield dates for the cooling of magma at the time of eruption. Disequilibrium of some short-lived daughters of the uranium series such as 210Po may be fractionated by saturation of a volatile phase and can be employed to date magmatic gas loss that is synchronous with volcanic eruption (e.g., Rubin et al. 1994).

  6. Series Bosch System Development (United States)

    Abney, Morgan B.; Evans, Christopher; Mansell, Matt; Swickrath, Michael


    State-of-the-art (SOA) carbon dioxide (CO2) reduction technology for the International Space Station produces methane as a byproduct. This methane is subsequently vented overboard. The associated loss of hydrogen ultimately reduces the mass of oxygen that can be recovered from CO2 in a closed-loop life support system. As an alternative to SOA CO2 reduction technology, NASA is exploring a Series-Bosch system capable of reducing CO2 with hydrogen to form water and solid carbon. This results in 100% theoretical recovery of oxygen from metabolic CO2. In the past, Bosch-based technology did not trade favorably against SOA technology due to a high power demand, low reaction efficiencies, concerns with carbon containment, and large resupply requirements necessary to replace expended catalyst cartridges. An alternative approach to Bosch technology, labeled "Series-Bosch," employs a new system design with optimized multi-stage reactors and a membrane-based separation and recycle capability. Multi-physics modeling of the first stage reactor, along with chemical process modeling of the integrated system, has resulted in a design with potential to trade significantly better than previous Bosch technology. The modeling process and resulting system architecture selection are discussed.

  7. On Implications of the Devonian Hydrothermal Sedimentary Faci es in the Qinling Orogeny%秦岭造山带泥盆系热水沉积岩相应用研究及实例

    Institute of Scientific and Technical Information of China (English)

    方维萱; 张国伟; 胡瑞忠; 刘方杰


    构造-热水沉积岩相与盆地的古地理环境, 热水沉积岩相与热水沉积成矿,热(水) 流体岩相与构造背景、构造古地理,它们之间有密切地内在联系.应用热水沉积岩相、沉积相及沉积体系分析方法,对凤县铅硐山-双石铺三级构造热水成矿盆地进行研究。%The Qinling orogenic belt is located in the central China and is one of the most important intracontinental orogeny in the world. Devonian sedimentary basins are the major accumulation structures for Au-Ag-Pb-Zn deposits in the area. Fengtai Devonian pull-apart basin, one of the accumulation basins in the Qinling orogeny, hosted a series of large-superlarge Au-Pb-Zn deposits such as Qiandongshan and Dongtangzi large Pb-Zn deposits and Baguamiao superlarge Au deposits. Lead-zinc orebodies hosted at a suite of hydrothermal depositional rocks in the three-order hydrothermal basins. Therefore, research on relationship between the hydrothermal depositional facies and the three-order hydrothermal basin is the best way to understand the relationship between metal deposits and the hydro thermal depositional basin.   The concept of hydrothermal sedimentary rock facies at the Devonian in the Qinling orogeny has been initiated. Relationships between tectonic hydrothermal sedimentary facies and paleo-geographic framework of sedimentary basin, between hydrothermal sedimentary facies and mineralization of hydrothermal depositions, and between hydrothermal sedimentary facies and tectonic geographic framework are very important in the analysis of sedimentary basin. On the basis of associat ions of the hydrothermal sedimentary facies, sedimentary lithofacies, and sedime ntary system, the Qiandongshan-Shuangshipu third-order hydrothermal deposition al basin has been analyzed in this paper. Three depositional systems are recogni zed in the Qiandongshan-Shuangshipu third-order hydrothermal depositional basin. Carbonate rock formation was formed in a shallow

  8. Classification scheme for sedimentary and igneous rocks in Gale crater, Mars (United States)

    Mangold, N.; Schmidt, M. E.; Fisk, M. R.; Forni, O.; McLennan, S. M.; Ming, D. W.; Sautter, V.; Sumner, D.; Williams, A. J.; Clegg, S. M.; Cousin, A.; Gasnault, O.; Gellert, R.; Grotzinger, J. P.; Wiens, R. C.


    Rocks analyzed by the Curiosity rover in Gale crater include a variety of clastic sedimentary rocks and igneous float rocks transported by fluvial and impact processes. To facilitate the discussion of the range of lithologies, we present in this article a petrological classification framework adapting terrestrial classification schemes to Mars compositions (such as Fe abundances typically higher than for comparable lithologies on Earth), to specific Curiosity observations (such as common alkali-rich rocks), and to the capabilities of the rover instruments. Mineralogy was acquired only locally for a few drilled rocks, and so it does not suffice as a systematic classification tool, in contrast to classical terrestrial rock classification. The core of this classification involves (1) the characterization of rock texture as sedimentary, igneous or undefined according to grain/crystal sizes and shapes using imaging from the ChemCam Remote Micro-Imager (RMI), Mars Hand Lens Imager (MAHLI) and Mastcam instruments, and (2) the assignment of geochemical modifiers based on the abundances of Fe, Si, alkali, and S determined by the Alpha Particle X-ray Spectrometer (APXS) and ChemCam instruments. The aims are to help understand Gale crater geology by highlighting the various categories of rocks analyzed by the rover. Several implications are proposed from the cross-comparisons of rocks of various texture and composition, for instance between in place outcrops and float rocks. All outcrops analyzed by the rover are sedimentary; no igneous outcrops have been observed. However, some igneous rocks are clasts in conglomerates, suggesting that part of them are derived from the crater rim. The compositions of in-place sedimentary rocks contrast significantly with the compositions of igneous float rocks. While some of the differences between sedimentary rocks and igneous floats may be related to physical sorting and diagenesis of the sediments, some of the sedimentary rocks (e

  9. Local properties of Fourier series


    Hüseyin Bor


    A theorem on local property of |N¯,pn|k summability of factored Fourier series, which generalizes some known results, and also a general theorem concerning the |N¯,pn|k summability factors of Fourier series have been proved.

  10. GPS Position Time Series @ JPL (United States)

    Owen, Susan; Moore, Angelyn; Kedar, Sharon; Liu, Zhen; Webb, Frank; Heflin, Mike; Desai, Shailen


    Different flavors of GPS time series analysis at JPL - Use same GPS Precise Point Positioning Analysis raw time series - Variations in time series analysis/post-processing driven by different users. center dot JPL Global Time Series/Velocities - researchers studying reference frame, combining with VLBI/SLR/DORIS center dot JPL/SOPAC Combined Time Series/Velocities - crustal deformation for tectonic, volcanic, ground water studies center dot ARIA Time Series/Coseismic Data Products - Hazard monitoring and response focused center dot ARIA data system designed to integrate GPS and InSAR - GPS tropospheric delay used for correcting InSAR - Caltech's GIANT time series analysis uses GPS to correct orbital errors in InSAR - Zhen Liu's talking tomorrow on InSAR Time Series analysis

  11. Series of Reciprocal Triangular Numbers (United States)

    Bruckman, Paul; Dence, Joseph B.; Dence, Thomas P.; Young, Justin


    Reciprocal triangular numbers have appeared in series since the very first infinite series were summed. Here we attack a number of subseries of the reciprocal triangular numbers by methodically expressing them as integrals.

  12. The recent marine sedimentary record of Baranof Island, Southeast Alaska - implications for paleoclimate reconstructions (United States)

    Addison, J. A.; Finney, B. P.; Jaeger, J. M.; Stoner, J. S.; Norris, R. D.; Hangsterfer, A.


    Modern and paleoclimate studies suggest a correlation between Pacific decadal climate variability and marine ecosystem productivity, but are generally limited by either short periods of observation or low temporal resolution. Long, annually resolved paleoclimate time-series data are thus critical for assessing this correlation and understanding the full range of Pacific climate variability and its impacts. Baranof Island is located in the Alexander Archipelago of Southeast Alaska, and contains many temperate ice-free fjords with shallow sills that enhance organic matter preservation by restricting oxygenation of bottom waters. Multicore samples EW0408-32MC and 43MC were recovered from two fjords on Baranof Island, and analyzed to determine how recent sedimentation patterns relate to the instrument record as a first step towards reconstructing high-latitude Pacific climate at annual timescales. A combination of radiometric 137Cs and excess 210Pb geochronometry, 3D computerized tomography (CT), and high-resolution Avaatech scanning XRF geochemical analyses were used to investigate this relationship. Scanning XRF data were collected every 2 mm on core 32MC, while 43MC was measured at 0.2 mm intervals. Core 32MC is composed of a diffusely laminated to bioturbated clay with a maximum apparent steady-state sedimentation rate of ~5±1 mm/yr, while core 43MC is a strongly laminated diatom ooze with a maximum apparent sedimentation rate of ~6±0.5 mm/yr. Using conservative estimates of accumulation to assess basal ages of the cores yields approximately ~AD 1930 for 32MC, and ~AD 1900 for 43MC. Scanning XRF centered natural log-ratio transformed [clr] element intensities indicate 32MC is controlled by a balance between detrital (Al, Si, K, Ti, Fe, and Ca) and biogenic components (S and Br), and isolated peaks in clr Ca data correspond with CT-visible shell debris. Core 43MC is more complex, with both XRF and CT scans indicating four distinct lithologies: (i) millimeter

  13. The diagram for phyllotactic series

    Directory of Open Access Journals (Sweden)

    Joanna Szymanowska-Pułka


    Full Text Available Many authors studying phyllotaxis in various plant species have reported the occurrence of many different numbers of contact parastichy pairs that are members of different Fibonacci-like series. On the basis of these reports a diagram was constructed in which any theoretically possible series was represented by the two first members of a given series.

  14. Harmonic Series Meets Fibonacci Sequence (United States)

    Chen, Hongwei; Kennedy, Chris


    The terms of a conditionally convergent series may be rearranged to converge to any prescribed real value. What if the harmonic series is grouped into Fibonacci length blocks? Or the harmonic series is arranged in alternating Fibonacci length blocks? Or rearranged and alternated into separate blocks of even and odd terms of Fibonacci length?

  15. Wavelet analysis on paleomagnetic (and computer simulated VGP time series

    Directory of Open Access Journals (Sweden)

    A. Siniscalchi


    Full Text Available We present Continuous Wavelet Transform (CWT data analysis of Virtual Geomagnetic Pole (VGP latitude time series. The analyzed time series are sedimentary paleomagnetic and geodynamo simulated data. Two mother wavelets (the Morlet function and the first derivative of a Gaussian function are used in order to detect features related to the spectral content as well as polarity excursions and reversals. By means of the Morlet wavelet, we estimate both the global spectrum and the time evolution of the spectral content of the paleomagnetic data series. Some peaks corresponding to the orbital components are revealed by the spectra and the local analysis helped disclose their statistical significance. Even if this feature could be an indication of orbital influence on geodynamo, other interpretations are possible. In particular, we note a correspondence of local spectral peaks with the appearance of the excursions in the series. The comparison among the paleomagnetic and simulated spectra shows a similarity in the high frequency region indicating that their degree of regularity is analogous. By means of Gaussian first derivative wavelet, reversals and excursions of polarity were sought. The analysis was performed first on the simulated data, to have a guide in understanding the features present in the more complex paleomagnetic data. Various excursions and reversals have been identified, despite of the prevalent normality of the series and its inherent noise. The found relative chronology of the paleomagnetic data reversals was compared with a coeval global polarity time scale (Channel et al., 1995. The relative lengths of polarity stability intervals are found similar, but a general shift appears between the two scales, that could be due to the datation uncertainties of the Hauterivian/Barremian boundary.

  16. Globe: Lecture series

    CERN Multimedia


    The LHC: an accelerator of science This series of lectures is all about understanding the scientific and technological challenges of the phenomenal LHC project and assessing its innovations through their everyday applications. Come and take a sneak preview of the LHC! Communicate: the Grid, a computer of global dimensions François Grey, head of communication in CERN’s Information Technology Department How will it be possible for the 15 million billion bytes of data generated by the LHC every year to be handled and stored by a computer that doesn’t have to be the size of a skyscraper? The computer scientists have the answer: the Grid, which will harness the power of tens of thousands of computers all over the world by creating a network of computers and making them operate as one. >>> Lectures are free and require no specialist knowledge. In french. 
 >>> By reservation only: tel. +41 (0)22 767 76 76

  17. SERI Biomass Program (United States)

    Bergeron, P. W.; Corder, R. E.; Hill, A. M.; Lindsey, H.; Lowenstein, M. Z.


    The biomass with which this report is concerned includes aquatic plants, which can be converted into liquid fuels and chemicals; organic wastes (crop residues as well as animal and municipal wastes), from which biogas can be produced via anerobic digestion; and organic or inorganic waste streams, from which hydrogen can be produced by photobiological processes. The Biomass Program Office supports research in three areas which, although distinct, all use living organisms to create the desired products. The Aquatic Species Program (ASP) supports research on organisms that are themselves processed into the final products, while the Anaerobic Digestion (ADP) and Photo/Biological Hydrogen Program (P/BHP) deals with organisms that transform waste streams into energy products. The P/BHP is also investigating systems using water as a feedstock and cell-free systems which do not utilize living organisms. This report summarizes the progress and research accomplishments of the SERI Biomass Program during FY 1982.

  18. New approaches in the indirect quantification of thermal rock properties in sedimentary basins: the well-log perspective

    DEFF Research Database (Denmark)

    Fuchs, Sven; Balling, Niels; Förster, Andrea

    capacity in sedimentary rocks derived from data provided by standard geophysical well logs. The approach is based on a data set of synthetic sedimentary rocks (clastic rocks, carbonates and evaporates) composed of mineral assemblages with variable contents of 15 major rock-forming minerals and porosities......: Fuchs, Sven; Balling, Niels; Förster, Andrea (2015): Calculation of thermal conductivity, thermal diffusivity and specific heat capacity of sedimentary rocks using petrophysical well logs. Geophysical Journal International 203, 1977-2000, doi: 10.1093/gji/ggv403...

  19. Quantitative bounds on morphodynamics and implications for reading the sedimentary record. (United States)

    Ganti, Vamsi; Lamb, Michael P; McElroy, Brandon


    Sedimentary rocks are the archives of environmental conditions and ancient planetary surface processes that led to their formation. Reconstructions of Earth's past surface behaviour from the physical sedimentary record remain controversial, however, in part because we lack a quantitative framework to deconvolve internal dynamics of sediment-transport systems from environmental signal preservation. Internal dynamics of landscapes--a consequence of the coupling between bed topography, sediment transport and flow dynamics (morphodynamics)--result in regular and quasiperiodic landforms that abound on the Earth and other planets. Here, using theory and a data compilation of morphodynamic landforms that span a wide range of terrestrial, marine and planetary depositional systems, we show that the advection length for settling sediment sets bounds on the scales over which internal landscape dynamics operate. These bounds provide a universal palaeohydraulic reconstruction tool on planetary surfaces and allow for quantitative identification of depositional systems that may preserve tectonic, climatic and anthropogenic signals.

  20. Late Holocene sedimentary environments of south San Francisco Bay, California, illustrated in gravity cores (United States)

    Woodrow, Donald L.; Fregoso, Theresa A.; Wong, Florence L.; Jaffe, Bruce E.


    Data are reported here from 51 gravity cores collected from the southern part of San Francisco Bay by the U.S. Geological Survey in 1990. The sedimentary record in the cores demonstrates a stable geographic distribution of facies and spans a few thousand years. Carbon-14 dating of the sediments suggests that sedimentation rates average about 1 mm/yr. The geometry of the bay floor and the character of the sediment deposited have remained about the same in the time spanned by the cores. However, the sedimentary record over periods of centuries or decades is likely to be much more variable. Sediments containing a few bivalve shells and bivalve or oyster coquinas are most often found west of the main channel and near the San Mateo Bridge. Elsewhere in the south bay, shells are rare except in the southernmost reaches where scattered gastropod shells are found.

  1. Modeling of the Sedimentary Interbedded Basalt Stratigraphy for the Idaho National Laboratory Probabilistic Seismic Hazard Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Suzette Payne


    This report summarizes how the effects of the sedimentary interbedded basalt stratigraphy were modeled in the probabilistic seismic hazard analysis (PSHA) of the Idaho National Laboratory (INL). Drill holes indicate the bedrock beneath INL facilities is composed of about 1.1 km of alternating layers of basalt rock and loosely consolidated sediments. Alternating layers of hard rock and “soft” loose sediments tend to attenuate seismic energy greater than uniform rock due to scattering and damping. The INL PSHA incorporated the effects of the sedimentary interbedded basalt stratigraphy by developing site-specific shear (S) wave velocity profiles. The profiles were used in the PSHA to model the near-surface site response by developing site-specific stochastic attenuation relationships.

  2. Modeling of the Sedimentary Interbedded Basalt Stratigraphy for the Idaho National Laboratory Probabilistic Seismic Hazard Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Suzette Payne


    This report summarizes how the effects of the sedimentary interbedded basalt stratigraphy were modeled in the probabilistic seismic hazard analysis (PSHA) of the Idaho National Laboratory (INL). Drill holes indicate the bedrock beneath INL facilities is composed of about 1.1 km of alternating layers of basalt rock and loosely consolidated sediments. Alternating layers of hard rock and “soft” loose sediments tend to attenuate seismic energy greater than uniform rock due to scattering and damping. The INL PSHA incorporated the effects of the sedimentary interbedded basalt stratigraphy by developing site-specific shear (S) wave velocity profiles. The profiles were used in the PSHA to model the near-surface site response by developing site-specific stochastic attenuation relationships.

  3. Effect of a thick inverted sedimentary package on seismic wave propagation in the lower crust (United States)

    Roy-Chowdhury, K.; Dobreflection Working Group


    High quality seismic deep reflection data was acquired across the Donbas inverted basin in The Ukraine during the summer of 2000. The 80-fold (nominal) vibrator operation supported by lower-fold explosive acquisition resulted in a good data quality. Detailed analysis of the shallower (basin) part of the wave-field - not reported here - has produced a good 2-D velocity model for the thick sedimentary cover overlying the middle and the lower crust in this area. The sedimentary structures show the effects of large-scale tectonic disturbances involving folding and both normal- and thrust- faulting. Seismic waves propagating on their way to- and from- the lower crustal region interact with this shallower medium and undergo complex interaction involving scattering, focussing and defocussing. This effect will be studied by analysing the lower-crustal signals for coherent arrivals with/without the effect of the overburden. An attempt will be made to quantify the effect using an empirical technique.

  4. Estimation of Sedimentary Thickness in Kachchh Basin, Gujarat Using SP Converted Phase (United States)

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


    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.

  5. The tectonic development and erosion of the Knox Subglacial Sedimentary Basin, East Antarctica (United States)

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


    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.

  6. Isotopic evidence of magmatism and a sedimentary carbon source at the Endeavour hydrothermal system

    Energy Technology Data Exchange (ETDEWEB)

    Brown, T A; Proskurowski, G; Lilley, M D


    Stable and radiocarbon isotope measurements made on CO{sub 2} from high temperature hydrothermal vents on the Endeavour Segment of the Juan de Fuca Ridge indicate both magmatic and sedimentary sources of carbon to the hydrothermal system. The Endeavour segment is devoid of overlying sediments and has shown no observable signs of surficial magmatic activity during the {approx}20 years of ongoing studies. The appearance of isotopically heavy, radiocarbon dead CO{sub 2} after a 1999 earthquake swarm requires that this earthquake event was magmatic in origin. Evidence for a sedimentary organic carbon source suggests the presence of buried sediments at the ridge axis. These findings, which represent the first temporally coherent set of radiocarbon measurements from hydrothermal vent fluids, demonstrate the utility of radiocarbon analysis in hydrothermal studies. The existence of a sediment source at Endeavour and the occurrence of magmatic episodes illustrate the extremely complex and evolving nature of the Endeavour hydrothermal system.

  7. UAS-based quantification of sedimentary body changes at Langgriesgraben, Styria, Austria (United States)

    Schöttl, Stefan; Seier, Gernot; Rascher, Eric; Sulzer, Wolfgang; Sass, Oliver


    The creek's sedimentary body at Langgriesgraben is characterized by inconstant but recurring earth surface changes. Mass transport and deposition occur partly spontaneously and endanger primary infrastructure, in particular a main road. It is often mentioned in literature that the use of small and lightweight UAS is promising. To contribute to that, this study focuses on the documentation and quantification of carried sedimentary material by using a hexacopter in a high alpine environment. The images which were captured on two different dates, allow generating orthophotos and DEMs. The comparison of these derivatives enables a deeper understanding of the sedimentary body and its conditions. Our specific study area is a part of a bigger research area of another research project (Sedyn-X). One of the main goals of that project is to create a conceptual model of the sedimentary cascade for the entire Johnsbachtal catchment and to quantify geomorphic processes (e.g. erosion, transport and rearrangement of sediments). Therefore Terrestrial Laser Scanning recordings are performed as well. Through the generated surface models from different eras, changes in surface and volume can be quantified. The photogrammetric surface models can be compared with almost simultaneous ALS and TLS recordings. Apart from that, the outcomes will provide hard facts for decision-makers. The UAS related processing steps and methods (e.g. DGPS, SfM) are more or less established and well-known, but the applicability of UAS for recording feasible data, has to be proved constantly. We assume that our results will answer concrete questions and thus reduce expected damage and costs.

  8. Characteristics and applications of isotopes in products from organic matter in sedimentary rocksby simulated thermal experiments

    Institute of Scientific and Technical Information of China (English)

    陈安定; 张文正; 徐永昌


    Isotopic compositions of carbon in the products obtained respectively from 25 sedimentary rocks at an early stage of maturation by the simulated thermogenetic hydrocarbons experiments have been determined. The fractional effect of methane carbon isotope during the thermal maturation of organic matter is observed. Based on the experimental data, the relative equations between δ13C and R0 were established and have been used for differentiation of origins of various kinds of natural gases in the Shan-Gan-Ning Basin.

  9. Hydrodynamic controls of morpho-sedimentary evolution in a rockbounded mesotidal estuary. Tina Menor (N Spain)


    Flor Blanco, G.; Flor, G.; Morales González, Juan Antonio; Pando, L.


    The Tina Menor estuary is a highly confined incised valley with advanced sedimentary infilling. The outstanding feature of this estuary is its longitudinal zonation, which forms four segments from the outer to the inner limit: Mouth complex, Bay, Tidal flats and Upper channel. The innermost part of the Bay and the Tidal Flats (semi-reclaimed areas) are broader estuarine zones, whereas the Mouth Complex and outermost Bay are confined by narrow rocky outcrops. This paper explains the d...

  10. Direct stable isotope porewater equilibration and identification of groundwater processes in heterogeneous sedimentary rock. (United States)

    David, Katarina; Timms, Wendy; Baker, Andy


    The off-axis integrated cavity output spectrometry (ICOS) method to analyse porewater isotopic composition has been successfully applied over the last decade in groundwater studies. This paper applies the off-axis ICOS method to analyse the porewater isotopic composition, attempts to use the isotopic shift in groundwater values along with simple geochemical mixing model to define the groundwater processes in the Sydney Basin, Australia. Complementary data included geophysical, hydrogeological, geochemical, and mineralogical investigations. Porewater from core samples were analysed for δ(18)O and δ(2)H from various sedimentary units in the Basin and compared to endpoint water members. Stable δ(18)O and δ(2)H values of porewaters in the Basin (-9.5 to 2.8‰ for δ(18)O and -41.9 to 7.9‰ for δ(2)H) covered a relatively narrow range in values. The variability in water isotopes reflects the variability of the input signal, which is the synoptic variability in isotopic composition of rainfall, and to a minor extent the subsequent evaporation. The porosity, bulk density and mineralogy data demonstrate the heterogeneity that adds the complexity to variations in the isotope profile with depth. The source of chloride in the sedimentary sequence was related to rock-water and cement/matrix-water interaction rather than to evaporation. The heterogeneous character of the sedimentary rock strata was supported by a change in pore pressures between units, density and variability in rock geochemical analyses obtained by using X-ray fluorescence (XRF) and X-ray power diffraction analyses. This research identified distinct hydrogeological zones in the Basin that were not previously defined by classic hydrogeological investigations. Isotopic signature of porewaters along the detailed vertical profile in combination with mineralogical, geochemical, geophysical and hydrogeological methods can provide useful information on groundwater movement in deep sedimentary environments. The

  11. Composition of dispersed sedimentary matter and fluxes in the water column of the Caspian Sea (United States)

    Lisitzin, A. P.; Lukashin, V. N.


    This article presents the first data on the chemical composition of dispersed matter from sediment traps with analysis of the sedimentary components that constitute suspended particulate matter (amorphous silica, organic matter (OM), carbonates, and lithogenic matter). It is established that the annual variability of fluxes demonstrates its seasonal growth in spring and summer. High fluxes of these components over the northern and southern slopes of the Derbent Basin are determined by deposition of material from the nepheloid layer formed by the contour current.

  12. Sedimentary basins classification: a commented review; Classificacao de bacias sedimentares: uma revisao comentada

    Energy Technology Data Exchange (ETDEWEB)

    Martins-Neto, Marcelo A. [Universidade Federal de Ouro Preto (UFOP), MG (Brazil). Nucleo de Geologia do Petroleo; Fundacao Gorceix, Ouro Preto, MG (Brazil)]. E-mail:


    During the evolution of the knowledge regarding sedimentary basins, many authors have discussed criteria and proposed schemes for their classification, most of them driven by geo tectonic theories like Geossinclinal and Plate Tectonics. Firstly, the present paper discusses the definition of a sedimentary basin, since there are two different approaches in the literature. The first is based on geo dynamic criteria, where basins are defined by their linked subsidence mechanisms, related to a single tectonic regime or tectonic-thermal event, responsible for the development of a first-order basin cycle. According to the second approach, a basin is defined as a region characterized by the accumulation of a thick sedimentary package during a long time span, regardless the existence of significant hiatuses and/or unconformities inside the package and the stacking of more than one first-order cycle. After a historical synthesis about the classification of sedimentary basins, the merits and efficiency of classification proposals are discussed, including the particular case of the intracratonic basins, as well as perspectives for the future. It is concluded that the basic classification criteria proposed by Dickinson (1974), although incomplete and/or deficient in some aspects, are very efficient for practical purposes, mostly by emphasizing the type of plate interaction (tectonic regime) during sedimentation (if divergent, convergent or strike-slip). The approach explaining the evolution of basins based on plate interactions solved the major problem of the previous classification schemes that was the proliferation of names for particular cases, as well as has direct implications in terms of stress field, structural and stratigraphic styles, being very efficient in the definition of the type of basin and having a predictive character in terms of processes and products. (author)

  13. Recognizing the threshold magnetic anisotropy for inclination shallowing: Implications for correcting inclination errors of sedimentary rocks

    Directory of Open Access Journals (Sweden)

    Yongxiang eLi


    Full Text Available Post-depositional compaction is an integral part of sedimentary rock formation and thus has been reasonably deemed as a major culprit for the long-recognized inclination-shallowing problem in sedimentary rocks. Although theoretical treatment elegantly envisions magnetic anisotropy (or oblate fabrics to correspond to the degree of compaction and the magnitude of inclination flattening, such correspondence has rarely been seen in nature quantitavely, which leaves the possibility of misidentification and/or over-correction for inclination shallowing using magnetic anisotropy. This is because the extent to which oblate magnetic fabrics are developed strongly enough for inclination to start becoming shallow is not yet known. Here, we present sedimentary paleomagnetic data from two ~6 m long gravity cores GHE24L and GHE27L from the northern slope of the South China Sea to examine the down-core changes in magnetic anisotropy and inclinations, and to explore the possible connection between the two parameters. The results show that oblate fabrics are dominantly developed at depths >~2m and the degree of anisotropy displays an overall gradual increase with depth. Inclination shallowing occurs in the > 5m segment of the relatively distal core GHE27L and the amount of shallowing largely correlates with the degree of anisotropy, suggesting a causal relation between the development of magnetic anisotropy and the degree of inclination shallowing. Examination of down-core changes in inclination and magnetic anisotropy suggests that a threshold anisotropy of PAMS~1.04 and PAAR~1.10 exists for inclination shallowing in the cores. For PAAR10° if particle anisotropy is <1.4. This study provides strong field evidence that complements and substantiates the theoretical model and suggests that the threshold anisotropy can be used as a first-order criterion to identify inclination errors of some sedimentary rocks.

  14. Visualizing the sedimentary response through the orogenic cycle using multi-dimensional scaling (United States)

    Spencer, C. J.; Kirkland, C.


    Changing patterns in detrital provenance through time have the ability to resolve salient features of an orogenic cycle. Such changes in the age spectrum of detrital minerals can be attributed to fluctuations in the geodynamic regime (e.g. opening of seaways, initiation of subduction and arc magmatism, and transition from subduction to collisional tectonics with arrival of exotic crustal material). These processes manifest themselves through a variety of sedimentary responses due to basin formation, transition from rift to drift sedimentation, or inversion and basement unroofing. This generally is charted by the presence of older detrital zircon populations during basement unroofing events and is followed by a successive younging in the detrital zircon age signature either through arrival of young island arc terranes or the progression of subduction magmatism along a continental margin. The sedimentary response to the aforementioned geodynamic environment can be visualized using a multi-dimensional scaling approach to detrital zircon age spectra. This statistical tool characterizes the "dissimilarity" of age spectra of the various sedimentary successions, but importantly also charts this measure through time. We present three case studies in which multi-dimensional scaling reveals additional useful information on the style of basin evolution within the orogenic cycle. The Albany-Fraser Orogeny in Western Australia and Grenville Orogeny (sensu stricto) in Laurentia demonstrate clear patterns in which detrital zircon age spectra become more dissimilar with time. In stark contrast, sedimentary successions from the Meso- to Neoproterozoic North Atlantic Region reveal no consistent pattern. Rather, the North Atlantic Region reflects a signature consistent with significant zircon age communication due to a distal position from an orogenic front, oblique translation of terranes, and complexity of the continental margin. This statistical approach provides a mechanism to

  15. A Preliminary Analysis of Relations Between Tectonic Deformation of Sedimentary Cover and Basement in Kuqa Depression

    Institute of Scientific and Technical Information of China (English)

    Liu Jie; Qu Guosheng; Tong Xiaoguang; Song Huizhen; Zhou Qing; Zhang Ning


    Study of seismic activity in the Kuqa area enables us to infer some possible active faults in basement from the ePicentral distribution on different profiles. The relations between active faults in the basement and surface structures are analyzed and the difference between sedimentary cover and basement in their deformation characteristics and the genesis are discussed. The following conclusions have been drawn: (1) the epicentral distribution indicates that, the east Qiulitag and south and north Qiulitag deep faults in the basement correspond to the east and west Qiulitag anticlines, respectively. Moreover, deep faults also exist beneath the Yiqiklik and Yaken anticlines. It indicates that the formation of surface structures is controlled by deep structures; (2) A NE-trending strike-slip fault develops along the line from the western termination of Yiqiklik structure to Dongqiu Well 5 and a NW-trending active fault on the western side of Baicheng. The two active faults across the tectonic strike are the main causes for tectonic segmentation of the Kuqa depression and possibly the cause for the middle segment (Kuqa-Baicheng) of the depression to be more shortened than both its eastern and western terminations; (3) The difference between the sedimentary cover and basement in their deformation characteristics depends mainly on the different properties of media between them.The lithospheric strength of the basement in the basin is fairly high, which determines the basement deformation to be mainly of brittle fracture seismic activity. While the strength of sedimentary cover is low, where there exist weak thin layers, such as coal and gyps. Under the effect of strong tectonic compression, the sedimentary rocks may undergo strong viscous or plastic flow deformation; meanwhile, an aseismic detachment may take place along the weak layers.

  16. Modern sedimentary environments and dynamic depositional systems in the southern Yellow Sea

    Institute of Scientific and Technical Information of China (English)


    Based on analyses of more than 600 surface sediment samples together with large amounts of previous sedimentologic and hydrologic data, the characteristics of modern sedimentary environments and dynamic depositional systems in the southern Yellow Sea (SYS) are expounded, and the controversial formation mechanism of muddy sediments is also discussed. The southern Yellow Sea shelf can be divided into low-energy sedimentary environment and high-energy sedimentary environment; the low- energy sedimentary environment can be further divided into cyclonic and anticyclonic ones, and the high-energy environment is subdivided into high-energy depositional and eroded environments. In the shelf low-energy environments, there developed muddy depositional system. In the central part of the southern Yellow Sea, there deposited the cold eddy sediments under the actions of a meso-scale cyclonic eddy (cold eddy), and in the southeast of the southern Yellow Sea, an anticyclonic eddy muddy depositional system (warm eddy sediment) was formed. These two types of sediments showed evident differences in grain size, sedimentation rate, sediment thickness and mineralogical characteristics. The high-energy environments were covered with sandy sediments on seabed; they appeared mainly in the west, south and northeast of the southern Yellow Sea. In the high-energy eroded environment, large amounts of sandstone gravels were distributed on seabed. In the high-energy depositional environment, the originally deposited fine materials (including clay and fine silt) were gradually re-suspended and then transported to a low-energy area to deposit again. In this paper, the sedimentation model of cyclonic and anticyclonic types of muddy sediments is established, and a systematic interpretation for the formation cause of muddy depositional systems in the southern Yellow Sea is given.

  17. Advanced Horizontal Well Recirculation Systems for Geothermal Energy Recovery in Sedimentary and Crystalline Formations

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, Mike S. [Terralog Technologies USA, Inc., Calgary (Canada); Detwiler, Russell L. [Terralog Technologies USA, Inc., Calgary (Canada); Lao, Kang [Terralog Technologies USA, Inc., Calgary (Canada); Serajian, Vahid [Terralog Technologies USA, Inc., Calgary (Canada); Elkhoury, Jean [Terralog Technologies USA, Inc., Calgary (Canada); Diessl, Julia [Terralog Technologies USA, Inc., Calgary (Canada); White, Nicky [Terralog Technologies USA, Inc., Calgary (Canada)


    There is increased recognition that geothermal energy resources are more widespread than previously thought, with potential for providing a significant amount of sustainable clean energy worldwide. Recent advances in drilling, completion, and production technology from the oil and gas industry can now be applied to unlock vast new geothermal resources, with some estimates for potential electricity generation from geothermal energy now on the order of 2 million megawatts. The primary objectives of this DOE research effort are to develop and document optimum design configurations and operating practices to produce geothermal power from hot permeable sedimentary and crystalline formations using advanced horizontal well recirculation systems. During Phase I of this research project Terralog Technologies USA and The University of California, Irvine (UCI), have completed preliminary investigations and documentation of advanced design concepts for paired horizontal well recirculation systems, optimally configured for geothermal energy recovery in permeable sedimentary and crystalline formations of varying structure and material properties. We have also identified significant geologic resources appropriate for application of such technology. The main challenge for such recirculation systems is to optimize both the design configuration and the operating practices for cost-effective geothermal energy recovery. These will be strongly influenced by sedimentary formation properties, including thickness and dip, temperature, thermal conductivity, heat capacity, permeability, and porosity; and by working fluid properties.

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

    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


    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.

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

    Energy Technology Data Exchange (ETDEWEB)

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


    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.

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

    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.


    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.

  1. Paleosecular variation during the PCRS based on a new database of sedimentary and volcanic records (United States)

    Haldan, M. M.; Langereis, C. G.; Evans, M. E.


    We present a paleosecular variation study using a generalised global paleomagnetic sedimentary and volcanic database. We made use of all available (and suitable) - published and some new- sedimentary and volcanic paleomagnetic records corresponding to the Permo-Carboniferous Reversed Superchron (PCRS) interval to reanalyse all data. We focused on records with a sufficient number of samples, and acquired - whenever possible - the original data, or - as a second choice - parametrised published site means. Analysis of these paleomagnetic data in terms of latitude variation of the scatter of the virtual geomagnetic poles (VGPs) suggests that careful data selection is required and that some of the older studies may need to be redone using more modern methods, both in terms of sampling and laboratory treatment. In addition, high (southern and especially northern hemisphere) latitudes are notably lacking in published records. The transitional data is removed using a variable VGP cut-off angle which varies with latitude. We use also our extended sedimentary records from Permian red beds from the Lodève and Dôme de Barrot basins (S. France), a new detailed paleomagnetic study of the Permian volcanics in the Oslo graben (Norway), as well as new data from Carboniferous-Permian sediments from the Donbas basin (Ukraine). We compare our results with those from published paleosecular variation models and with recent (re)analyses of VGP scatter during different periods of the geological archive.

  2. Sedimentary cover deformations in the equatorial Atlantic and their comparison with geophysical fields (United States)

    Sokolov, S. Yu.


    The deformations of the sedimentary cover at near-latitudinal geotraverses west and east of the Mid-Atlantic Ridge in the equatorial part of ocean are compared with potential fields and variations of the V p/ V s attribute at a depth of 470 km. The features of sedimentary cover deformations in abyssal basins are formulated, as well as their differences from the undisturbed bedding of sediments. The elements of chain of phenomena with common spatial manifestations and cause-and-effect relationships have been established, including heterogeneous horizontal movements, which make up macrojointing above "cold" mantle blocks at a depth of 470 km; serpentinization of upper-mantle rocks; the formation of superposed magnetic anomalies; the release of the fluids, which acoustically bleach out the sedimentary sequence in seismic imaging; and decompaction of rocks leading to vertical motions and forced folding. The origin of the Atlantic marginal dislocation zone is explained. The coincidence of the deformation boundary in the equatorial Atlantic with the zero contour line of the V p/ V s attribute is revealed. This coincidence is an indicator of the rheological state of the upper mantle.

  3. Neogene sedimentary evolution of Baja California in relation to regional tectonics (United States)

    Helenes, J.; Carreño, A. L.


    During the Neogene, the tectonic and sedimentary evolution of the Baja California Peninsula followed four stages: (1) during the early Miocene (22 Ma), the initiation of transform motion between Pacific and North American plates, caused a rapid subsidence in the Continental Borderland Province and in some adjacent areas.This subsidence coincided in time with with a global rise in sea level. At this time, the eastern and southern parts of the peninsula did not show any evidence of subsidence. (2) During the middle Miocene (12 Ma), normal and strike slip faulting migrated eastward, causing subsidence in the northern part of the Gulf of California, where the oldest Tertiary marine sedimentary rocks were deposited. The areas in central Baja California Sur and the central part of the Gulf itself received abundant volcanic deposits related to continental extension. (3) During the late Miocene (8 Ma), the western margin of the Peninsula changed to a slightly compressive regime, while the northern part of the Gulf contained a marine basin with upper bathyal environments. The central area of the Gulf continued receiving abundant volcanic deposits, while the Los Cabos block received marine sedimentation, correlatable with sedimentary units reported from the continental margins in Nayarit, Jalisco and Michoacán. (4) Beginning in the early Pliocene (5 Ma), the present configuration of the Gulf of California developed through right-lateral strike slip and extension in the Gulf itself. Since Pliocene times, the Gulf presents widespread marine sedimentation with deep basins reaching lower bathyal depths.

  4. Integrated techniques to evaluate the features of sedimentary rocks of archaeological areas of Sicily

    Directory of Open Access Journals (Sweden)

    Maria Brai


    Full Text Available Sicily includes a great variety of lithologies, giving a high complexity to the geologic landscape. Their prevalent lithology is sedimentary. It is well known that rocks of sedimentary origin, compared with metamorphic and volcanic deposits, can be relatively soft and hence fairly easy to model. Nevertheless, this workability advantage is a drawback for Cultural Heritage applications. In fact, these materials show a high porosity, with pore-size distributions that lead to deterioration through absorption of water. In this paper, several sedimentary rocks used in historical Cultural Heritage items of Sicily, from "Magna Graecia" to nowadays, are classified for mineralogical features, chemical composition, and for porosity. Particularly, some samples collected in quarries relevant to the archaeological sites of 41 Agrigento, Segesta and Selinunte will be considered and characterized using integrated techniques (XRD, XRF, NMR and CT. Data on samples obtained in laboratory will be compared with the relevant values measured in situ on monuments of historical-cultural interest of the quoted archaeological places.

  5. The Sedimentary Characteristics and Formation Mechanism of Shell Ridges Along the Southwest Coast of Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    LIU Zhijie; ZHUANG Zhenye; HAN Deliang; QI Xingfen


    The present paper studies the sedimentary characteristics and mechanism of the shell ridges on the southwestern coast of Bohai Bay, which are the largest and have the highest shell (or shell fragment) content in the world. These shell ridges are composed of two sedimentary subfacies: the ridge subfacies and the ridge infill subfacies with different inner textures and sedimentary structures. The ridge subfacies primarily consists of fresh shells and/or shell fragments with parallel beddings and high-angle oblique beddings. The ridge infill subfacies consists of finer shell fragments and silty sand with parallel beddings oblique to land. The evolution of the shell ridge is controlled by the accumulation of substantial shell material,the relative slow erosion of shoreline, storm waves, winds and the shift of river routes. Wind tunnel tests indicate that the critical movement velocity of shell is lower than that of quartz sand of the same grain size. Deltaic progradation alternates with shell ridge growth. While the Yellow River empties into the sea through this area, accompanied by deltaic progradating, the shell material is scarce, which is unfavorable to the growth of the shell ridge. Conversely, erosion occurs along an abandoned delta coast where a shell ridge may develop, e.g. the shell ridge on the southwest of Bohai Bay.

  6. Potential Cement Phases in Sedimentary Rocks Drilled by Curiosity at Gale Crater, Mars (United States)

    Rampe, E. B.; Morris, R. V.; Bish, D. L.; Chipera, S. J.; Ming, D. W.; Blake, D. F.; Vaniman, D. T.; Bristow, T. F.; Cavanagh, P.; Farmer, J. D.; Morrison, S. M.; Siebach, K.; Treiman, A. H.; Achilles, C. N.; Blaney, D.; Crisp, J. A.; Des Marais, D. J.; Downs, R. T.; Fendrich, K.; Martin-Torres, J.; Morookian, J. M.; Zorzano, M.-P.; Sarrazin, P.; Spanovich, N.; Yen, A. S.


    The Mars Science Laboratory rover Curiosity has encountered a variety of sedimentary rocks in Gale crater with different grain sizes, diagenetic features, sedimentary structures, and varying degrees of resistance to erosion. Curiosity has drilled three rocks to date and has analyzed the mineralogy, chemical composition, and textures of the samples with the science payload. The drilled rocks are the Sheepbed mudstone at Yellowknife Bay on the plains of Gale crater (John Klein and Cumberland targets), the Dillinger sandstone at the Kimberley on the plains of Gale crater (Windjana target), and a sedimentary unit in the Pahrump Hills in the lowermost rocks at the base of Mt. Sharp (Confidence Hills target). CheMin is the Xray diffractometer on Curiosity, and its data are used to identify and determine the abundance of mineral phases. Secondary phases can tell us about aqueous alteration processes and, thus, can help to elucidate past aqueous environments. Here, we present the secondary mineralogy of the rocks drilled to date as seen by CheMin and discuss past aqueous environments in Gale crater, the potential cementing agents in each rock, and how amorphous materials may play a role in cementing the sediments.

  7. Assessment of undiscovered conventional oil and gas resources of the Western Canada Sedimentary Basin, Canada, 2012 (United States)

    Higley, Debra


    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Porro, C.; Augustine, C.


    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.

  9. Hydrothermal circulation in an anisotropic sedimentary basin: Application to the Okinawa back arc basin

    Energy Technology Data Exchange (ETDEWEB)

    Genthon, P.; Rabinowicz, M. (Groupe de Recherches de Geodesie, Spatiale (France)); Foucher, J.P.; Sibuet, J.C. (Inst. Francais de Recherches pour l' Exploitation de la Mer, Plouzane (France))


    The authors explore the pattern of two-dimensional convection in an highly anisotropical porous medium. This physical situation is relevant to passive margin sedimentary basins consisting of interbedded coarse-grained pervious and shale matrix. They show that permeability anisotropies of the order of 10{sup 2}-10{sup 4} allow for long convective cells, of aspect ratio greater than 10, but that a combination of this parameter with a slight slope of the order of a few percent of the sedimentary layers is required to stabilize these long cells. As an example, they present the Okinawa basin, an active submarine back arc basin, with a sedimentary thickness of about 2 km and a heat flow profile across this basin, varying from 32 to 232 mWm{sup {minus}2} over a distance of 30 km. It is shown that this heat flow variation is difficult to explain with conductive mechanisms only but is well reproduced by different convective models relying on permeability anisotropy plus slope. Although the insufficient thermal and structural constraints did not allow them to build a unique model, the whole set of possible fits to the heat flow data may restrict the mean hydraulic parameters of the basin. A vertical permeability of a few tens of milidarcy and an anisotropy greater than 100 are required to produce the expected stable and active large-scale circulation. It is suggested in conclusion that this type of circulation might be active in oil- or oil-forming element migration.

  10. Sedimentary iron inputs stimulate seagrass ( Posidonia oceanica) population growth in carbonate sediments (United States)

    Marbà, Núria; Duarte, Carlos M.; Holmer, Marianne; Calleja, Maria Ll.; Álvarez, Elvira; Díaz-Almela, Elena; Garcias-Bonet, Neus


    The relationship between sedimentary Fe inputs and net seagrass population growth across a range of Posidonia oceanica meadows growing in carbonate Mediterranean sediments (Balearic Islands, Spain; SE Iberian Peninsula, Spain; Limassol, Cyprus; Sounion, Greece) was examined using comparative analysis. Sedimentary Fe inputs were measured using benthic sediment traps and the net population growth of P. oceanica meadows was assessed using direct census of tagged plants. The meadows examined ranged from meadows undergoing a severe decline to expanding meadows (specific net population growth, from -0.14 yr -1 to 0.05 yr -1). Similarly, Fe inputs to the meadows ranged almost an order of magnitude across meadows (8.6-69.1 mg Fe m -2 d -1). There was a significant, positive relationship between sedimentary iron inputs and seagrass net population growth, accounting for 36% of the variability in population growth across meadows. The relationship obtained suggested that seagrass meadows receiving Fe inputs below 43 mg Fe m -2 d -1 are vulnerable and in risk of decline, confirming the pivotal role of Fe in the control of growth and the stability of seagrass meadows in carbonate sediments.

  11. Molecular Records of Primary Producers and Sedimentary Environmental Conditions of Late Permian Rocks in Northeast Sichuan, China

    Institute of Scientific and Technical Information of China (English)

    Ruan Xiaoyan; Luo Genming; Hu Shouzhi; Chen Feng; Sun Si; Wu Wenjun; Guo Qiaozhen; Liu Guoquan


    A series of biomarkers were identified in the aliphatic and aromatic fractions of the extracts from Late Permian Dalong (大隆) and Wujiaping (吴家坪) formations in Shangsi (上寺) Section, Northeast Sichuan (四川), South China, on the basis of the analysis of gas chromatography-mass spectrometry (GC-MC). The dominance of lower-molecular-weight n-alkanes throughout the profile suggests the dominant contribution of algae and bacteria to the organics preserved in the marine section. Wujiaping Formation is characterized by the elevated contribution from algae as well as other photoantotrophs such as photosynthetic bacteria as shown by the molecular ratios of hopanes to steranes or tricyclic terpanes as well as the ratio of pristane (Pr) and phytane (Ph) to C17 and C18 n-alkanes. This is in accord with the data from the microscopic measurement on the calcareous algae. In contrast, Dalong Formation is featured by enhanced contribution from bacteria and probably terrestrial organics indicated by the enhanced C24 tetracyclic terpanes relative to tricyclic terpanes. The two formations also show a distinct discrimination in sedimentary environmental conditions including redox condition and salinity. The anoxic condition was only found in the middle of the Dalong Formation as shown by the ratios of Pr/Ph and dibenzothiophene to phenanthrene, consistent with the reported data of Mo and U. An enhancedsalinity indicated by the homohopane index is observed at the shallow Wujiaping Formation. On the basis of the composition of primary productivity and the redox condition, Dalong Formation is proposed, herein, to be potential hydrocarbon source rocks in the study site. It is notable that the topmost end-Permian is characterized by a large perturbance in both the redox condition and salinity, with oxic conditions being frequently interrupted by short-term anoxia, likely showing a causal relationship with the episodic biotic crisis across the Permian-Triassic boundary.

  12. In-situ Micro-structural Studies of Gas Hydrate Formation in Sedimentary Matrices (United States)

    Kuhs, Werner F.; Chaouachi, Marwen; Falenty, Andrzej; Sell, Kathleen; Schwarz, Jens-Oliver; Wolf, Martin; Enzmann, Frieder; Kersten, Michael; Haberthür, David


    The formation process of gas hydrates in sedimentary matrices is of crucial importance for the physical and transport properties of the resulting aggregates. This process has never been observed in-situ with sub-micron resolution. Here, we report on synchrotron-based micro-tomographic studies by which the nucleation and growth processes of gas hydrate were observed in different sedimentary matrices (natural quartz, glass beds with different surface properties, with and without admixtures of kaolinite and montmorillonite) at varying water saturation. The nucleation sites can be easily identified and the growth pattern is clearly established. In under-saturated sediments the nucleation starts at the water-gas interface and proceeds from there to form predominantly isometric single crystals of 10-20μm size. Using a newly developed synchrotron-based method we have determined the crystallite size distributions (CSD) of the gas hydrate in the sedimentary matrix confirming in a quantitative and statistically relevant manner the impressions from the tomographic reconstructions. It is noteworthy that the CSDs from synthetic hydrates are distinctly smaller than those of natural gas hydrates [1], which suggest that coarsening processes take place in the sedimentary matrix after the initial hydrate formation. Understanding the processes of formation and coarsening may eventually permit the determination of the age of gas hydrates in sedimentary matrices [2], which are largely unknown at present. Furthermore, the full micro-structural picture and its evolution will enable quantitative digital rock physics modeling to reveal poroelastic properties and in this way to support the exploration and exploitation of gas hydrate resources in the future. [1] Klapp S.A., Hemes S., Klein H., Bohrmann G., McDonald I., Kuhs W.F. Grain size measurements of natural gas hydrates. Marine Geology 2010; 274(1-4):85-94. [2] Klapp S.A., Klein H, Kuhs W.F. First determination of gas hydrate

  13. Direct stable isotope porewater equilibration and identification of groundwater processes in heterogeneous sedimentary rock

    Energy Technology Data Exchange (ETDEWEB)

    David, Katarina, E-mail: [School of Mining Engineering, UNSW Australia, NSW 2052 (Australia); Connected Waters Initiative Research Centre, UNSW Australia, NSW 2052 (Australia); Timms, Wendy [School of Mining Engineering, UNSW Australia, NSW 2052 (Australia); Connected Waters Initiative Research Centre, UNSW Australia, NSW 2052 (Australia); Baker, Andy [Connected Waters Initiative Research Centre, UNSW Australia, NSW 2052 (Australia)


    The off-axis integrated cavity output spectrometry (ICOS) method to analyse porewater isotopic composition has been successfully applied over the last decade in groundwater studies. This paper applies the off-axis ICOS method to analyse the porewater isotopic composition, attempts to use the isotopic shift in groundwater values along with simple geochemical mixing model to define the groundwater processes in the Sydney Basin, Australia. Complementary data included geophysical, hydrogeological, geochemical, and mineralogical investigations. Porewater from core samples were analysed for δ{sup 18}O and δ{sup 2}H from various sedimentary units in the Basin and compared to endpoint water members. Stable δ{sup 18}O and δ{sup 2}H values of porewaters in the Basin (− 9.5 to 2.8‰ for δ{sup 18}O and − 41.9 to 7.9‰ for δ{sup 2}H) covered a relatively narrow range in values. The variability in water isotopes reflects the variability of the input signal, which is the synoptic variability in isotopic composition of rainfall, and to a minor extent the subsequent evaporation. The porosity, bulk density and mineralogy data demonstrate the heterogeneity that adds the complexity to variations in the isotope profile with depth. The source of chloride in the sedimentary sequence was related to rock–water and cement/matrix–water interaction rather than to evaporation. The heterogeneous character of the sedimentary rock strata was supported by a change in pore pressures between units, density and variability in rock geochemical analyses obtained by using X-ray fluorescence (XRF) and X-ray power diffraction analyses. This research identified distinct hydrogeological zones in the Basin that were not previously defined by classic hydrogeological investigations. Isotopic signature of porewaters along the detailed vertical profile in combination with mineralogical, geochemical, geophysical and hydrogeological methods can provide useful information on groundwater movement in

  14. Landform assemblages and sedimentary processes along the Norwegian Channel Ice Stream (United States)

    Ottesen, Dag; Stokes, Chris R.; Bøe, Reidulv; Rise, Leif; Longva, Oddvar; Thorsnes, Terje; Olesen, Odleiv; Bugge, Tom; Lepland, Aave; Hestvik, Ole B.


    Several regional and detailed bathymetric datasets together with 2D and 3D seismic data are compiled to investigate the landform assemblages and sedimentary processes along the former path of the Norwegian Channel Ice Stream (NCIS). At the broad scale, the glacial geomorphology and sedimentary architecture reveals three different zones along the ice-stream path, characterized by: (1) glacial erosion in the onset zone and inner shelf area, (2) sediment transport through the main trunk of the ice stream across the mid-shelf, and (3) a zone of deposition towards the outer continental shelf edge. Along the first 400 km of the ice stream bed (outer Oslofjord-Skagerrak-Stavanger) a major overdeepening is associated with suites of crag-and-tail features at the transition from the crystalline bedrock to the sedimentary bedrock, together with evidence of glaciotectonic thrusting in the form of hill-hole pairs. Here we interpret extensive erosion of both sedimentary rocks and Quaternary sediments. This zone is succeeded by an approximately 400 km long zone, through which most of the sediments eroded from the inner shelf were transported, rather than being deposited. We infer that sediment was transported subglacially and is likely to have been advected downstream by soft sediment deformation. The thickness of till of inferred Weichselian age generally varies from 0 and 50 m and this zone is characterized by mega-scale glacial lineations (MSGLs) which we interpret to be formed in a dynamic sedimentary system dominated by high sediment fluxes, but with some localized sediment accretion associated with lineations. Towards the shelf break, the North Sea Fan extends to the deep Norwegian Sea, and reflects massive sedimentation of glacigenic debris onto the continental slope. Numerous glacigenic debris flows accumulated and constructed a unit up to 400 m thick during the Last Glacial Maximum. The presence of these three zones (erosion, transport, deposition) is consistent with

  15. Sedimentary Environments of the Sea Floor off Eastern Cape Cod, Massachusetts (CC_ENVIRON.SHP, Geographic, WGS84) (United States)

    U.S. Geological Survey, Department of the Interior — This data set includes the sedimentary environments for the sea floor offshore of northern and eastern Cape Cod, Massachusetts. This interpretation is based on data...

  16. Time-transgressive tunnel-valley infill revealed by a three- dimensional sedimentary model, Hamburg, north-west Germany

    DEFF Research Database (Denmark)

    Janszen, Adriaan; Moreau, Julien; Moscariello, Andrea


    Deep, elongated incisions, often referred to as tunnel valleys, are among the most characteristic landforms of formerly glaciated terrains. It is commonly thought that tunnel valleys were formed by meltwater flowing underneath large ice sheets. The sedimentary infill of these features is often......-west Germany) were investigated using a dataset of 1057 deep wells containing lithological and geophysical data. The stratigraphic correlations and the resulting three-dimensional lithological model were used to assess the spatial lithological distributions and sedimentary architecture. The sedimentary...... of glacial recession appears to have been an important control on the sedimentary architecture of the tunnel-valley fill. During periods of stagnation, thick ice-proximal deposits accumulated at the ice margin, while during rapid recession, only a thin veneer of such coarse-grained sediments was deposited...

  17. Characterizing the Biological and Geochemical Architecture of Hydrothermally Derived Sedimentary Deposits: Coupling Micro Raman Spectroscopy with Noble Gas Spectrometry (United States)

    Bower, D. M.; Conrad, P. G.; Steele, A.; Fries, M. D.


    The chemical species in cherts and glass fragments were analyzed using micro Raman spectroscopy in conjunction with measurements of heavy noble gas isotopes to characterize hydrothermally derived sedimentary environments.

  18. Dissolved particulate and sedimentary humic acids in the mangroves and estuarine ecosystem of Goa, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Sardessai, S.

    Highest concentration of humic acids in all the three forms (dissolved, particulate and sedimentary) was found in the monsoon (June-September) when the salinity was minimum while the lowest concentrations was observed in the premonsoon (February...

  19. `Indoor` series vending machines; `Indoor` series jido hanbaiki

    Energy Technology Data Exchange (ETDEWEB)

    Gensui, T.; Kida, A. [Fuji Electric Co. Ltd., Tokyo (Japan); Okumura, H. [Fuji Denki Reiki Co. Ltd., Tokyo (Japan)


    This paper introduces three series of vending machines that were designed to match the interior of an office building. The three series are vending machines for cups, paper packs, cans, and tobacco. Among the three series, `Interior` series has a symmetric design that was coated in a grain pattern. The inside of the `Interior` series is coated by laser satin to ensure a sense of superior quality and a refined style. The push-button used for product selection is hot-stamped on the plastic surface to ensure the hair-line luster. `Interior Phase II` series has a bay window design with a sense of superior quality and lightness. The inside of the `Interior Phase II` series is coated by laser satin. `Interior 21` series is integrated with the wall except the sales operation panel. The upper and lower dress panels can be detached and attached. The door lock is a wire-type structure with high operativity. The operation block is coated by titanium color. The dimensions of three series are standardized. 6 figs., 1 tab.

  20. From Fourier Series to Rapidly Convergent Series for Zeta(3)

    DEFF Research Database (Denmark)

    Scheufens, Ernst E


    The article presents a mathematical study which investigates the exact values of the Riemann zeta (ζ) function. It states that exact values can be determined from Fourier series for periodic versions of even power functions. It notes that using power series for logarithmic functions on this such ......The article presents a mathematical study which investigates the exact values of the Riemann zeta (ζ) function. It states that exact values can be determined from Fourier series for periodic versions of even power functions. It notes that using power series for logarithmic functions...

  1. Sedimentary dykes in the Oskarshamn-Vaestervik area. A study of the mechanism of formation

    Energy Technology Data Exchange (ETDEWEB)

    Roeshoff, Kennert [BBK AB, Solna (Sweden); Cosgrove, John [Imperial College, London (United Kingdom). Dept. of Earth Sciences and Engineering


    This study of the sedimentary dykes from the Oskarshamn-Vaestervik area, near Aespoe and surrounding region, is aimed at understanding the mechanism of their formation. In particular it is important to establish whether or not they formed by the injection of high pressure fluidized sediments and if so what the likely effect of any future over pressured sediments will be on the stability of the fracture network in the basement rocks at Aespoe. This report is made up of a review of the literature on sedimentary dykes, a discussion of the various mechanical models for hydraulic fracturing and a description of the field and laboratory study carried out on the sedimentary dykes. The literature review indicates a remarkable consensus on the mode of formation of these structures based on their fabric (particularly layering generated in part by variation in clast size) and the composition of the infilling material. Two modes of origin have been recognised. These are the passive infilling of dykes where the dyke material has entered an open fracture under the influence of gravity, and active, i.e. forceful injection of a fluidized sediment under high pressure into a pre-existing fracture or into a fracture generated by the high pressure fluid. The discussion of the theory of fluid induced fracturing leads to the recognition of three systems which are the two end members and an intermediate form of a complete spectrum of materials ranging from unconsolidated and incohesive sediments, through cemented but porous rocks to crystalline rocks with no intrinsic porosity and whose only porosity relates to that imparted by the fracture network that the rock contains. The theory best suited to analyses this latter system is one based on fracture mechanics and is known as the theory of external hydraulic fracturing. From the point of view of the sedimentary dykes in the study area around the Aespoe Hard Rock Laboratory, where the dykes occur in the fractured granitic basement, this is

  2. Impact of cable bacteria on sedimentary iron and manganese dynamics in a seasonally-hypoxic marine basin


    Sulu-Gambari, F; Seitaj, D.; Behrends, T.; D. Banerjee; Meysman, F. J. R.; Slomp, C. P.


    Cable bacteria have recently been identified in various sedimentary 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 sedimentary Fe and Mn dynamics at three sites located along a water depth gradient in a seasonally-hypoxic coastal marine...


    Institute of Scientific and Technical Information of China (English)


    <正>20111628 Bao Hanyong(State Key Laboratory of Marine Geology,Tongji University,Shanghai 200092,China);Han Guangmin Clay Mineral Analysis of the Early Triassic Tempestites,Lower Yangtze Region(Journal of Jilin University,ISSN1671-5888,CN22-1343/P,40(4),2010,p.947-954,5 illus.,1 table,19 refs.,with English abstract)Key words:tempestite deposit,clay minerals,Yangtze Region


    Institute of Scientific and Technical Information of China (English)


    <正>20091542 Cai Xiyao(West Branch,Research Institute of Petroleum Exploration and Development,SINOPEC,Urumqi 830011,China);Wu Yasheng Paleoecology of Middle-Upper Ordovician Reefal Community in Bachu,Xinjiang,Northwestern China(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,82(8),2008,p.1046-1051,1161,4 illus.,1 table,1 plate,18 refs.)Key words:reefs,XinjiangAt the Lianglitage Mountain in the eastern Bachu area,Xinjiang outcrops the Lianglitage reefs(Yijianfang Formation)of Middle Ordovician and Kaidi reefs(mid Lianglitage Formation)of Upper Ordovician.The former has echinoderm banks reef-frame builders,which consists of receptaculitids and formed typical framestone.Primary porosities widely developed at the centre of receptaculitids,

  5. Sedimentary Facies Models on Carbonatite in the Upper Shuaiba Member of Lower Cretaceous in Daleel Field, Oman

    Institute of Scientific and Technical Information of China (English)

    Wang Feng; Jiang Zaixing; Zhou Liqing; Zhao Guoliang; Wang Lin; Zheng Ning; Xiang Shu'an


    The Upper Shuaiba Member (USH) is the main force pay bed in the Daleel field in northern Oman; 5 layers including A, B, C, D, and E were divided in profile, and layer D and layer E are the main beds. With the development of exploration in the Daieel oil field, studying the sedimentary systems about their inner composition and the collocation in dimension, and setting up the sedimentary models in the USH are becoming more and more necessary and important to meet the further exploration requirement. Based on the data of geology, seism, and paleo-biology, according to the analysis method on carbonatite depositional system, the litho-facies assemblage and sedimentary environment in the USH were studied. Intershoal low-lying sub-facies (where the water depth is 10-50 m) and shallow shoal sub-facies (where the water depth is not more than 10 m) were extinguished in the layer D, and storm deposit was found in layer E1, in which intershoal low-lying sub-facies also developed. The feature of the sedimentary sub-facies and the sedimentary condition were analyzed, and the sedimentary model was set up in the article: the carbonatite intershoal low-lying developed under the background of open land in shallow sea, where storm events usually occurred in the Lower Cretaceous in the area.

  6. From source-to-sink: The Late Permian SW Gondwana paleogeography and sedimentary dispersion unraveled by a multi-proxy analysis (United States)

    Alessandretti, Luciano; Machado, Rômulo; Warren, Lucas Veríssimo; Assine, Mario Luis; Lana, Cristiano


    The Late Permian sedimentary succession of the Paraná Basin, southern Brazil, provide a valuable source of information about sediment provenance, tectonic processes and, consequently, the paleogeography of the southwestern Gondwana supercontinent. In order to understand the patterns of sedimentary dispersal and reconstruct the Late Permian source-to-sink dynamic, we report a complete series of U-Pb ages and Hf isotopic compositions of detrital zircons from the Rio do Rasto Formation sandstones allied with detailed paleocurrent and sedimentologic data. Our integrated provenance study reveals a consistent sediment transport from the south to the north and northwest. According to the evaluation of zircon ages and Hf isotopes, it was possible to determine four distinct source areas: (i) a distant Late Paleozoic active magmatic arc located in the southwestern Gondwana margin (i.e. Gondwanides Orogen), corresponding to the North Patagonian Massif; (ii) recycling of orthoquartzites from the uplifted Paleozoic Ventania Fold Belt and immature sandstones from the Claromecó Foreland Basin in central-eastern Argentina and the Silurian-Devonian successions of the southern Paraná Basin (central-northern Uruguay) and North Patagonian Massif; (iii) exhumed areas of the Archean-Paleoproterozoic basement and Neoproterozoic to Early Paleozoic mobile belts of the Damara in southwestern Africa and Ribeira Fold Belt in Uruguay and southern Brazil; and (iv) southeastward provenance of Grenvillian (1.2-1.0 Ga) zircons coming from the mafic to intermediate Mesoproterozoic igneous units of the Namaqua-Natal Belt in South Africa and Namibia. These data allow us to argue that sediments deposited in the Paraná Basin during the Late Permian come from both short- and long-distance source areas. In this context, an important population of Permian detrital zircons comes from the Gondwanides Orogen in the south, probably carried by transcontinental alluvial systems. Close to the source area

  7. An assessment of geochemical preparation methods prior to organic carbon concentration and carbon isotope ratio analyses of fine-grained sedimentary rocks (United States)

    KöNitzer, Sven F.; Leng, Melanie J.; Davies, Sarah J.; Stephenson, Michael H.


    This study summarizes organic carbon isotope (δ13C) and total organic carbon (TOC) data from a series of tests undertaken to provide an appropriate methodology for pre-analysis treatment of mudstones from an Upper Carboniferous sedimentary succession, in order to develop a consistent preparation procedure. The main treatments involved removing both inorganic carbonate and hydrocarbons (which might be extraneous) before δ13C and TOC analysis. The results show that decarbonating using hydrochloric acid causes significant reduction in δ13C and total carbon (TC) of the bulk material due to the removal of inorganic carbonate. These changes are most pronounced where soluble calcium carbonate (rather than Ca-Mg-Fe carbonate) is present. Deoiled samples show only slightly higher mean δ13C where visible bitumen was extracted from the bulk sample. Moreover, the isotopic signatures of the extracts are closely correlated to those of their respective bulk samples, suggesting that small yields of hydrocarbons were generated in situ with no isotopic fractionation. In addition, further δ13C and TC analyses were performed on samples where mixing of oil-based drilling mud with brecciated core material had been undertaken. Brecciated mudstone material did not display distinct isotopic signals compared to the surrounding fine-grained material. Overall we show that the most accurate assessment of bulk organic carbon isotopes and concentration in these samples can be achieved through decarbonating the material prior to measurement via the `rinse method'. However, our results support recent findings that pre-analysis acid treatments can cause variable and unpredictable errors in δ13C and TOC values. We believe that, despite these uncertainties, the findings presented here can be applied to paleoenvironmental studies on organic matter contained within sedimentary rocks over a range of geological ages and compositions.

  8. Digestive selection underlies differential utilization of phytoplankton and sedimentary organics by infaunal bivalves: Experiments with cockles (Cerastoderma edule) using cross-labelled mixed diets. (United States)

    Navarro, Enrique; Méndez, Soco; Urrutia, Miren Begoñe; Arambalza, Udane; Ibarrola, Irrintzi


    Differential utilization of phytoplankton and detrital particles present in natural sediments of mud-flats was studied in a series of experiments performed on the infaunal bivalve Cerastoderma edule. In order to assess digestive selection, parameters of food processing (organic ingestion rate: OIR, gross absorption efficiency: GAE and gut passage time: GPT) were recorded for each organic component in different combinations of food particles radio-labelled with (14)C. Experimental design included the use of both labelled diets of a sole organic component and cross-labelled diets; i.e., mixed suspensions presenting alternatively labelled one of the various components tested: phytoplankton cells, sedimentary organic particles and particulate detritus from vascular salt-marsh plants. Preferential absorption of phytoplankton was accounted for by absorption efficiency values that were two-fold those for sedimentary detritus when recorded with mixed diets of both organic components. Two factors contributed to this difference: a) higher digestibility of microalgae, measured as the ratio of GAE to GPT, and b) faster gut passage of detrital particles that results from digestive selection likely involving the preferential incorporation of phytoplankton into the digestive gland. However, when diets based on a sole organic component (either phytoplankton or detritus) were compared, larger GPT were recorded for detrital particles that enabled improving GAE of this rather refractory food. Overall results of these experiments are consistent with most studies in trophic ecology based on stable isotopes enrichment, concerning both the diversity of trophic sources used by marine bivalves and its preferential utilization of phytoplankton over phyto-detritus.

  9. Analysis of low-frequency climate periodicity in lacustrine sediments from the Enciso Group (Lower Cretaceous, Cameros basin, La Rioja, Spain) and its application to the correlation and dating of the series; Analisis de la periodicidad climatica de baja frecuencia registrada en los sedimentos lacustres del Grupo Enciso (Cretacico Inferior de la cuenca de Cameros, La Rioja): Aplicaciones a la correlacion y datacion de la serie

    Energy Technology Data Exchange (ETDEWEB)

    Angulo, A.; Munoz, A.


    We have characterized seven facies linked to three sedimentary environments: distal riverine, siliciclastic lacustrine and carbonate lacustrine, in the Lower Cretaceous syn-rift deposits in the Cameros basin (Enciso Group). The analysis was conducted on a 996-metre-thick series consisting of 74 sedimentary cycles. The facies were analysed using the Markov chains method. We identified three type-sequences linked to the recognised sedimentary environments. By studying the relationships between the facies we were able to develop a sedimentological model, with the relative position of each facies related to the lake shoreline. From this model we could construct a time series based on semi-quantitative depth (depth rank) and analyse it with the Wavelet and REDFIT programs. Spectral analysis identified periodic sedimentary cycles comparable to Milankovitch frequencies. The results show power-spectrum maxima (confidence level >99%) at 90.56 m, 16.66 m, 7.14 m, 5.37 m and 3.93 m. The sedimentary cycle interpreted as short eccentricity (16.66 m) is the most easily identifiable in the outcrop and constitutes the basis of our sequential analysis. The accumulation rate calculated for the Enciso Group is 175 m/Ma. Sedimentation of the Enciso Group at the Munilla section covers a time span of about 6 Ma, from the Upper Hauterivian to the the Middle Aptian. (Author)

  10. Recent benthic foraminifera and sedimentary facies distribution of the Abu Dhabi (United Arab Emirates) coastline (United States)

    Fiorini, Flavia; Lokier, Stephen W.


    The distribution of benthic foraminifera and sedimentary facies from Recent coastline environments adjacent to the coastline of Abu Dhabi (UAE) was studied in detail with the aim to: 1) provide reliable analogs for understanding and interpreting the depositional environment of ancient shallow-marine sediments from the UAE; 2) assess any modifications in the distribution of benthic environments and sedimentary facies in an area affected by significant anthropogenic activities - particular construction and land reclamation. A total of 100 sea-floor sediment samples were collected in different shallow-marine sedimentary environments (nearshore shelf, beach-front, channels, ooid shoals, lagoon and mangals) close to the coastline of Abu Dhabi Island. Where possible, we revisited the sampling sites used in several studies conducted in the middle of last century (prior to any significant anthropogenic activities) to assess temporal changes in Recent benthic foraminifera and sedimentary facies distribution during the last 50 years. Five foraminiferal assemblages were recognized in the studied area. Species with a porcellaneous test mainly belonging to the genera Quinqueloculina, Triloculina, Spiroloculina, Sigmoilinita are common in all studied areas. Larger benthic foraminifera Peneroplis and Spirolina are particularly abundant in samples collected on seaweed. Hyaline foraminifera mostly belonging to the genera Elphidium, Ammonia, Bolivina and Rosalina are also common together with Miliolidae in the nearshore shelf and beach front. Agglutinated foraminifera (Clavulina, Textularia, Ammobaculites and Reophax) are present in low percentages. The species belonging to the genera Ammobaculites and Reophax are present only in the finest grain samples particularly in lagoons and mangal environments and have not been reported previously in the studied area. The majority of the ooid shoal sediments, the coarser sediments of the beach-front and samples collected in dredged channels

  11. Gestures and metaphors as indicators of conceptual understanding of sedimentary systems (United States)

    Riggs, E. M.; Herrera, J. S.


    Understanding the geometry and evolution of sedimentary systems and sequence stratigraphy is crucial to the development of geoscientists and engineers working in the petroleum industry. There is a wide variety of audiences within industry who require relatively advanced instruction in this area of geoscience, and there is an equally wide array of approaches to teaching this material in the classroom and field. This research was undertaken to develop a clearer picture of how conceptual understanding in this area of sedimentary geology grows as a result of instruction and how instructors can monitor the completeness and accuracy of student thinking and mental models. We sought ways to assess understanding that did not rely on model-specific jargon but rather was based in physical expression of basic processes and attributes of sedimentary systems. Advances in cognitive science and educational research indicate that a significant part of spatial cognition is facilitated by gesture, (e.g. giving directions, describing objects or landscape features). We aligned the analysis of gestures with conceptual metaphor theory to probe the use of mental image-schemas as a source of concept representation for students' learning of sedimentary processes. In order to explore image schemas that lie in student explanations, we focused our analysis on four core ideas about sedimentary systems that involve sea level change and sediment deposition, namely relative sea level, base level, and sea-level fluctuations and resulting basin geometry and sediment deposition changes. The study included 25 students from three U.S. Midwestern universities. Undergraduate and graduate-level participants were enrolled in senior-level undergraduate courses in sedimentology and stratigraphy. We used semi-structured interviews and videotaping for data collection. We coded the data to focus on deictic, iconic, and metaphoric gestures, and coded interview transcripts for linguistic metaphors using the

  12. Inversion of the perturbation series

    Energy Technology Data Exchange (ETDEWEB)

    Amore, Paolo [Facultad de Ciencias, Universidad de Colima, Bernal DIaz del Castillo 340, Colima, Colima (Mexico); Fernandez, Francisco M [INIFTA (Conicet, UNLP), Division Quimica Teorica, Diag 113 S/N, Sucursal 4, Casilla de Correo 16, 1900 La Plata (Argentina)


    We investigate the inversion of the perturbation series and its resummation, and prove that it is related to a recently developed parametric perturbation theory. Results for some illustrative examples show that in some cases series reversion may improve the accuracy of the results.

  13. Convergence of a Catalan Series (United States)

    Koshy, Thomas; Gao, Zhenguang


    This article studies the convergence of the infinite series of the reciprocals of the Catalan numbers. We extract the sum of the series as well as some related ones, illustrating the power of the calculus in the study of the Catalan numbers.

  14. Complex Landscape Terms in Seri (United States)

    O'Meara, Carolyn; Bohnemeyer, Jurgen


    The nominal lexicon of Seri is characterized by a prevalence of analytical descriptive terms. We explore the consequences of this typological trait in the landscape domain. The complex landscape terms of Seri classify geographic entities in terms of their material make-up and spatial properties such as shape, orientation, and merological…

  15. Students' Conception of Infinite Series (United States)

    Martinez-Planell, Rafael; Gonzalez, Ana Carmen; DiCristina, Gladys; Acevedo, Vanessa


    This is a report of a study of students' understanding of infinite series. It has a three-fold purpose: to show that students may construct two essentially different notions of infinite series, to show that one of the constructions is particularly difficult for students, and to examine the way in which these two different constructions may be…

  16. The Lusi eruption and implications for understanding fossil piercement structures in sedimentary basins (United States)

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


    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.

  17. The effects of small dam removal on the distribution of sedimentary contaminants. (United States)

    Ashley, Jeffrey T F; Bushaw-Newton, Karen; Wilhelm, Matt; Boettner, Adam; Drames, Gregg; Velinsky, David J


    With increasing concern over degradation of aquatic resources, issues of liability, and maintenance costs, removal of small dams has become increasing popular. Although the benefits of removal seem to outweigh the drawbacks, there is a relative paucity of studies documenting the extent and magnitude of biological and chemical changes associated with dam removal, especially those evaluating potential changes in contaminant inventories. In August and November of 2000, a run-of-the-river dam on Manatawny Creek (southeast Pennsylvania) was removed in a two-stage process. To assess the effects of dam removal on the contaminant redistribution within the creek, sedimentary concentrations of polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and trace metals (Cd, Cr, Cu, Ni, Pb, Zn) were evaluated prior to and several months after removal. Pre- and post-removal analyses revealed elevated and spatially variable concentrations of total PAHs (ranging from approximately 200 to 81,000 ng(g dry weight) and low to moderate concentrations of trace metals and PCBs. The concentrations of these sedimentary contaminants pre- versus post-removal were not significantly different. Additionally, though the impoundment received storm water run-off and associated contaminants from the adjacent city of Pottstown, the total inventory of fine-grain sediments in the impoundment prior to removal was very low. The removal of the low-level Manatawny Creek dam did not significantly redistribute contaminants downstream. However, each dam removal should be assessed on a case by case basis where the potential of sedimentary contaminant redistribution upon dam removal exists.

  18. Realistic modelling of observed seismic motion in compIex sedimentary basins

    Directory of Open Access Journals (Sweden)

    G. F. Panza


    Full Text Available Three applications of a numerical technique are illustrated to model realistically the seismic ground motion for complex two-dimensional structures. First we consider a sedimentary basin in the Friuli region, and we model strong motion records from an aftershock of the 1976 earthquake. Then we simulate the ground motion caused in Rome by the 1915, Fucino (Italy earthquake, and we compare our modelling with the damage distribution observed in the town. Finally we deal with the interpretation of ground motion recorded in Mexico City, as a consequence of earthquakes in the Mexican subduction zone. The synthetic signals explain the major characteristics (relative amplitudes, spectral amplification, frequency content of the considered seismograms, and the space distribution of the available macroseismic data. For the sedimentary basin in the Friuli area, parametric studies demonstrate the relevant sensitivity of the computed ground motion to small changes in the subsurface topography of the sedimentary basin, and in the velocity and quality factor of the sediments. The relative Arias Intensity, determined from our numerical simulation in Rome, is in very good agreoment with the distribution of damage observed during the Fucino earthquake. For epicentral distances in the range 50 km-100 km, the source location and not only the local soil conditions control the local effects. For Mexico City, the observed ground motion can be explained as resonance effects and as excitation of local surface waves, and the theoretical and the observed maximum spectral amplifications are very similar. In general, our numerical simulations estimate the maximum and average spectral amplification for specific sites, i.e. they are a very powerful tool for accurate micro-zonation

  19. Pore Structure Characteristics and Permeability of Deep Sedimentary Rocks Determined by Mercury Intrusion Porosimetry

    Institute of Scientific and Technical Information of China (English)

    Na Zhang; Manchao He; Bo Zhang; Fengchao Qiao; Hailong Sheng; Qinhong Hu


    Pore structure characteristics of rock are a great concern for researchers and practitio-ners in rock mechanics and rock engineering fields. In this study, mercury intrusion porosimetry (MIP) was used to measure pore size distribution, as well as several important index parameters of pore structure, for seven common types of deep sedimentary rocks with a total of fifty rock samples. Results show a similar pore size distribution pattern of the rock samples in the same lithological group, but remarkable differences among different lithological groups. Among seven investigated rock types, mudstone has the smallest porosity of 3.37%, while conglomerate has the largest value of 18.8%. It is also found that the porosity of rock types with finer grain size is lower than those with coarser grain size. Meanwhile, a comparison of frequency distribution at ten intervals of pore-throat diameter among seven types of sedimentary rocks reveals that different rock types have different dominant pore-size ranges. Furthermore, permeability of the investigated sedimentary rock samples was derived based on MIP data using reported theoretical equations. Among seven rock types, mudstone has the lowest averaged permeability (3.64×10-6mD) while conglomerate has the highest one (8.59×10-4 mD). From mudstone to conglomerate, rock permeability increases with an increase of grain size, with only an exception of siltstone which has a relatively larger porosity value. Finally, regression analysis show that there is a good fitting (R2=0.95) between permeability and porosity which could be easily used to derive reliable permeability values of similar kinds of engineering rocks.

  20. Sedimentary features and exploration targets of Middle Permian reservoirs in the SW Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Guoming Xu


    Full Text Available The exploration direction and targets for the large-scale Middle Permian gas reservoirs in the Sichuan Basin are hot spots and challenges in current exploration researches. The exploration successes of large gas field of Cambrian Longwangmiao Formation in Gaoshiti-Moxi region, Central Sichuan Basin, indicated that prospective sedimentary facies belt was the basis for the formation of large gas fields. In this paper, based on seismic data, outcrop data and drilling data, the tectonic framework and sedimentary features of the Middle Permian in the SW Sichuan Basin were comprehensively studied. The following conclusions were reached from the perspective of sedimentary facies control: (1 during the Middle Permian, this region was in shallow water gentle slope belts with high energy, where thick reef flat facies were deposited; (2 the basement was uplifted during Middle Permian, resulting in the unconformity weathering crust at the top of Maokou Formation due to erosion; the SW Sichuan Basin was located in the karst slope belt, where epigenic karstification was intense; and (3 reef flat deposits superimposed by karst weathering crust was favorable for the formation of large-scale reef flat karst reservoirs. Based on the combination of the resources conditions and hydrocarbon accumulation conditions in this region, it was pointed out that the Middle Permian has great potential of large-scale reef flat karst gas reservoir due to its advantageous geological conditions; the Middle Permian traps with good hydrocarbon accumulation conditions were developed in the Longmen Mountain front closed structural belt in the SW Sichuan Basin and Western Sichuan Basin depression slope belt, which are favorable targets for large-scale reef flat karst reservoirs.

  1. Alteration of immature sedimentary rocks on Earth and Mars. Recording Aqueous and Surface-atmosphere Processes

    Energy Technology Data Exchange (ETDEWEB)

    Cannon, Kenneth M. [Brown Univ., Providence, RI (United States); Mustard, John F. [Brown Univ., Providence, RI (United States); Salvatore, Mark R. [Arizona State Univ., Mesa, AZ (United States)


    The rock alteration and rind formation in analog environments like Antarctica may provide clues to rock alteration and therefore paleoclimates on Mars. Clastic sedimentary rocks derived from basaltic sources have been studied in situ by martian rovers and are likely abundant on the surface of Mars. Moreover, how such rock types undergo alteration when exposed to different environmental conditions is poorly understood compared with alteration of intact basaltic flows. Here we characterize alteration in the chemically immature Carapace Sandstone from Antarctica, a terrestrial analog for martian sedimentary rocks. We employ a variety of measurements similar to those used on previous and current Mars missions. Laboratory techniques included bulk chemistry, powder X-ray diffraction (XRD), hyperspectral imaging and X-ray absorption spectroscopy. Through these methods we find that primary basaltic material in the Carapace Sandstone is pervasively altered to hydrated clay minerals and palagonite as a result of water–rock interaction. A thick orange rind is forming in current Antarctic conditions, superimposing this previous aqueous alteration signature. The rind exhibits a higher reflectance at visible-near infrared wavelengths than the rock interior, with an enhanced ferric absorption edge likely due to an increase in Fe3+ of existing phases or the formation of minor iron (oxy)hydroxides. This alteration sequence in the Carapace Sandstone results from decreased water–rock interaction over time, and weathering in a cold, dry environment, mimicking a similar transition early in martian history. This transition may be recorded in sedimentary rocks on Mars through a similar superimposition mechanism, capturing past climate changes at the hand sample scale. These results also suggest that basalt-derived sediments could have sourced significant volumes of hydrated minerals on early Mars due to their greater permeability compared with intact igneous rocks.

  2. Geochemical Characteristics of Sedimentary Manganese Deposit of Guichi, Anhui Province, China

    Institute of Scientific and Technical Information of China (English)


    The sedimentary manganese deposits occurring in Gufeng formation of the Permian in Guichi area, south Anhui Province, include manganese carbonate deposit formed by sedimentation, and manganese oxide deposit made by later oxidation. The total REE contents of these samples are relatively low ( < 250 × 10-6), belonging to LREE-enriched type,showing LREE enrichment during the process of formation of Mn deposit, especially during Mn-oxidizing process. Three normalized REE patterns and SCNA-normalized trace elements spider diagrams of the Mn-bearing sequence rocks and ores in this area reflect their same origin of ore sources, which is similar to rock-forming and ore-forming conditions. The Mnforming materials primarily came from the continent with higher mature degree and single material source. The δEu and δCe negative anomaly and Ce anomaly ( < - 0.1 ) manifest that Mn-bearing sequence of the Permian was mostly formed in marine basin and oxidative environment. The Sr and Ba anomaly, Sr/Ba and Co/Ni values reflect the Mn deposit environment was of deep water and high-salinity of marine facies. Although the Ce/La (mean 1.05), Y/Ho (25 ~ 41.5) and trace metals show a variety of correlations with Mn in the ten rock samples, which show multiple sources for the manganese, the analysis of geochemical characteristics indicate that the material sources of Mn deposit have been primarily terrestrially derived. Another source of the manganese probably comes from the seafloor volcanism in this area. Analysis of sedimentary features and geohistoric evolvement reveals that the maximum transgression of the Qixia Period, ore district is then in deep shelf-basin sedimentary setting and the Mn-bearing sequence is deposited.

  3. Sorting out compositional trends in sedimentary rocks of the Bradbury group (Aeolis Palus), Gale crater, Mars (United States)

    Siebach, K. L.; Baker, M. B.; Grotzinger, J. P.; McLennan, S. M.; Gellert, R.; Thompson, L. M.; Hurowitz, J. A.


    Sedimentary rocks are composed of detrital grains derived from source rocks, which are altered by chemical weathering, sorted during transport, and cemented during diagenesis. Fluvio-lacustrine sedimentary rocks of the Bradbury group, observed on the floor of Gale crater by the Curiosity rover during its first 860 Martian solar days, show trends in bulk chemistry that are consistent with sorting of mineral grains during transport. The Bradbury group rocks are uniquely suited for sedimentary provenance analysis because they appear to have experienced negligible cation loss (i.e., open-system chemical weathering) at the scale of the Alpha Particle X-ray Spectrometer bulk chemistry analyses based on low Chemical Index of Alteration values and successful modeling of >90% of the (volatile-free) targets as mixtures of primary igneous minerals. Significant compositional variability between targets is instead correlated to grain-size and textural characteristics of the rocks; the coarsest-grained targets are enriched in Al2O3, SiO2, and Na2O, whereas the finer-grained targets are enriched in mafic components. This is consistent with geochemical and mineralogical modeling of the segregation of coarse-grained plagioclase from finer-grained mafic minerals (e.g., olivine and pyroxenes), which would be expected from hydrodynamic sorting of the detritus from mechanical breakdown of subalkaline plagioclase-phyric basalts. While the presence of a distinctive K2O-rich stratigraphic interval shows that input from at least one distinctive alkali-feldspar-rich protolith contributed to basin fill, the dominant compositional trends in the Bradbury group are consistent with sorting of detrital minerals during transport from relatively homogeneous plagioclase-phyric basalts.

  4. Recirculation System for Geothermal Energy Recovery in Sedimentary Formations: Laboratory Experiments and Numerical Simulations (United States)

    Elkhoury, J. E.; Detwiler, R. L.; Serajian, V.; Bruno, M. S.


    Geothermal energy resources are more widespread than previously thought and have the potential for providing a significant amount of sustainable clean energy worldwide. In particular, hot permeable sedimentary formations provide many advantages over traditional geothermal recovery and enhanced geothermal systems in low permeability crystalline formations. These include: (1) eliminating the need for hydraulic fracturing, (2) significant reduction in risk for induced seismicity, (3) reducing the need for surface wastewater disposal, (4) contributing to decreases in greenhouse gases, and (5) potential use for CO2 sequestration. Advances in horizontal drilling, completion, and production technology from the oil and gas industry can now be applied to unlock these geothermal resources. Here, we present experimental results from a laboratory scale circulation system and numerical simulations aimed at quantifying the heat transfer capacity of sedimentary rocks. Our experiments consist of fluid flow through a saturated and pressurized sedimentary disc of 23-cm diameter and 3.8-cm thickness heated along its circumference at a constant temperature. Injection and production ports are 7.6-cm apart in the center of the disc. We used DI de-aired water and mineral oil as working fluids and explored temperatures from 20 to 150 oC and flow rates from 2 to 30 ml/min. We performed experiments on sandstone samples (Castlegate and Kirby) with different porosity, permeability and thermal conductivity to evaluate the effect of hydraulic and thermal properties on the heat transfer capacity of sediments. The producing fluid temperature followed an exponential form with time scale transients between 15 and 45 min. Steady state outflow temperatures varied between 60% and 95% of the set boundary temperature, higher percentages were observed for lower temperatures and flow rates. We used the flow and heat transport simulator TOUGH2 to develop a numerical model of our laboratory setting. Given

  5. Petrology and mineral chemistry of sedimentary rocks from the Western Solomon Sea (United States)

    Crook, Keith A. W.


    Sedimentary rocks from the northern margin of the Trobriand Platform, the north wall of the New Britain Trench, and the floor of the Solomon Sea Basin are volcaniclastics, mudrocks, and neritic and bathyal limestones. Arc-volcanic debris from calc-alkaline or high-K magmatic sources is present at each locality. A minor metamorphic component occurs at one site on the Trobriand Platform which yielded Early Eocene to Middle Miocene material, and at the New Britain Trench site, which yielded Miocene or older and post-Miocene samples. Solomon Sea Basin samples are mudrocks which are apparently no older than Late Pliocene.

  6. Seasonal variation of fluxes of dispersed sedimentary matter in the White Sea (Arctic ocean basin) (United States)

    Lisitzin, A. P.; Novigatsky, A. N.; Klyuvitkin, A. A.


    The monthly and seasonal quantity estimates of vertical fluxes of sedimentary matter from the White Sea performed during studies are the basis for the direct calculations of incoming chemical components, minerals, and various pollutants to the surface layer of bottom sediments. The White Sea, one of six Russian Arctic seas, may be considered as a megapolygon for further modern research using the new regularities of arctic sedimentogenesis established. This study focuses on the development of new technologies for complex studies of marine water areas using underwater sedimentation observatories, regular observations onboard vessels, and satellite oceanological data. The first priority task is year-round monitoring along the Northern Sea Route.

  7. Atmospheric oxygen regulation at low Proterozoic levels by incomplete oxidative weathering of sedimentary organic carbon (United States)

    Daines, Stuart J.; Mills, Benjamin J. W.; Lenton, Timothy M.


    It is unclear why atmospheric oxygen remained trapped at low levels for more than 1.5 billion years following the Paleoproterozoic Great Oxidation Event. Here, we use models for erosion, weathering and biogeochemical cycling to show that this can be explained by the tectonic recycling of previously accumulated sedimentary organic carbon, combined with the oxygen sensitivity of oxidative weathering. Our results indicate a strong negative feedback regime when atmospheric oxygen concentration is of order pO2~0.1 PAL (present atmospheric level), but that stability is lost at pO2biological productivity and resultant organic carbon burial drove the Great Oxidation Event.

  8. Sedimentary evolution models of Lower Triassic deep-water carbonate rocks of west Qinling Mts.

    Institute of Scientific and Technical Information of China (English)

    晋慧娟; 李育慈


    Based on the study of Lower Triassic deep-water carbonate rock sequence of west Qinling Mts . deep-water carbonate rock sequence is divided into lower fine-grain euxinic deposits of a carbonate gentle slope type and upper bathyal and abyssal sediments of carbonate steep slope type. The upper member is emphatically analysed and synthesized into five fades associations. They comprise four fining- and thinning-upward megacycles, each of them representing a sedimentary column which accumulated after a tensional fault subsidence event, which recorded a whole rifting process of west Qinling ocean trough during Lower Triassic.

  9. Monitoring of Sedimentary Fluxes in Cold Environments: The SEDIBUD (Sediment Budgets in Cold Environments) Programme (United States)

    Beylich, Achim A.


    Projected climate change in cold regions is expected to alter melt season duration and intensity, along with the number of extreme rainfall events, total annual precipitation and the balance between snowfall and rainfall. Similarly, changes to the thermal balance are expected to reduce the extent of permafrost and seasonal ground frost and increase active layer depths. These effects will undoubtedly change surface environments in cold regions and alter the fluxes of sediments, nutrients and solutes, but the absence of quantitative data and coordinated geomorphic process monitoring and analysis to understand the sensitivity of the Earth surface environment is acute in cold climate environments. The International Association of Geomorphologists` (I.A.G. / A.I.G.) SEDIBUD (Sediment Budgets in Cold Environments) Program (2005 - 2017) is addressing this existing key knowledge gap. The central research question of this global group of scientists is to: Assess and model the contemporary sedimentary fluxes in cold climates, with emphasis on both particulate and dissolved components. Research carried out at each of the ca. 50 defined SEDIBUD key test sites varies by program, logistics and available resources, but typically represent interdisciplinary collaborations of geomorphologists, hydrologists, ecologists, permafrost scientists and glaciologists. SEDIBUD has developed manuals and protocols (SEDIFLUX Manual) with a key set of primary surface process monitoring and research data requirements to incorporate results from these diverse projects and allow coordinated quantitative analysis across the program. Defined SEDIBUD key tasks for the coming years include (i) The continued generation and compilation of comparable longer-term datasets on contemporary sedimentary fluxes and sediment yields from SEDIBUD key test sites worldwide, (ii) The continued extension of the SEDIBUD metadata database with these datasets, (iii) The testing of defined SEDIBUD hypotheses (available

  10. A two-dimensional model of the passive coastal margin deep sedimentary carbon and methane cycles



    We present a new geologic-time and basin-spatial scale model of the continental margin methane cycle. The model, SpongeBOB, is used to simulate evolution of the carbon cycle in a passive sedimentary continental margin in response to changing oceanographic and geologic forcing over a time scale of 200 million years. The geochemistry of the sediment column is altered by the addition of vertical high-permeability channels intended to mimic the effects of heterogeneity in the real sediment column...

  11. Geology of East Egypt greenstone field in Neoproterozoic isoand arc: Reconstruction of Iron formation sedimentary environment. (United States)

    Kiyokawa, S.; Suzuki, T.


    Geology of East Egypt greenstone-granit belt which is northern part of Nubia shield was identified neoproterozoic island arc amalgamated sections. There are several iron formation within these greenstone belt. Age data shows this iron formation may be overlaped during 700 Ma Snowball period, how ever, there is no detail report of well preserved ice related evidences. We now started detail field work for identified tectonic reconstruction, original stratigraphy around Iron formation and sedimentary environment during the iron formation sedimentation area. East Egyptian shield was divided three geology, Proterozoic greenstone complex, 700-600 Granitic domes and cover sequence (Hammamet Group). We focus three area to identified sedimentary environment of iron sedimentation. Along the north-south trend of Wadi EL Dabban area are, we named Wadi branch as West site is RW-0 ~ 12, East site is RE-0 ~ 12 from north to south. Northern area is structurally moderate, southern portion is north dipping. Southern portion was intruded by granite and several place contain granitic dikes. Northeast to eastern area are identified younger sedimentary sequence (Hammamat Group) which is unconformablly overlay on the other iron formation bearing greenstone belt. Structurally these area is divided four units. Wadi was divided by right-lateral strike-ship fault. The displacement are more than 3 km. Also north dipping faults are identified.East-West trend fault are divided two units. It is divided NE, SE, NW and NS units.SW unit is most well preserved thick sequence of the Iron formation. SW unit is well preserved iron formation sequence within thick volcaniclastics. This unit mostly north dipping around 40-60 degree. Structural repetition in not well understand. Reconstract stratigraphy in this unit is at least 4000m in thickness. 5 member is identified in this sequence. Several thin iron formations are observed with in pillow lava and volcaniclastic sequence. These very thick

  12. Numerical aspects of modelling of coupled chemical reactions and fluid flow in sedimentary basins

    Energy Technology Data Exchange (ETDEWEB)

    Holstad, Astrid


    Simulation of coupled chemical reactions and fluid flow in porous sedimentary basins, through long time periods, is a numerical challenge. In most models available today the equations representing such a physical problem are solved as PDEs (Partial Differential Equation) where efficient time-stepping with controlled error is very difficult. The DAE (Differential Algebraic Equation) system approach is used where robust adaptive time-stepping algorithms are available in solvers. In this report mathematical and numerical models are derived for coupled chemical reactions and fluid flow. The models have several interesting properties which are discussed. The performance of code is tested. 20 refs., 6 figs., 2 tabs.

  13. Sedimentary facies and paleoenvironmental interpretation of a Holocene marsh in the Gironde Estuary in France

    Institute of Scientific and Technical Information of China (English)

    WANG Jianhua; MASSE Laurent; TASTET Jean-Pierre


    The Monards Marsh is located on the northeastern bank of the Gironde Estuary in France. Lithological, sedimentological and micropalaeontological investigations were made on four cores to determine the evolution of Holocene sedimentary environments and processes in this area over the last 6 000 a. Three main lithological facies are distinguished from bottom to top: (1) grey laminated silty-sandy clay; (2) homogeneous dark grey silty clay; and (3) compact silty clay. About 26 benthic foraminifera species are identified and divided into six groups according to their ecological characteristics. In association with lithology, sedimentary structures and grainulometry, the distribution of foraminifera group is used to define external slikke, internal slikke, external schorre, internal schorre, and continental marsh facies. Combined with 14C(AMS) dating, these data indicate four successive paleoenvironments in the Monards Marsh: (1) Holocene transgression resulted in the development of a basal schorre facies overlying fluvial deposits that transformed to slikke facies sedimentation; the transgression maximum occurred around 5 600 to 5 400 a BP and was inferred to be associated with the last phase of the rapid Holocene sea-level rise; (2) post-trangressive maximum sedimentation resulted in a regressive sequence of deposits prograding towards the estuary, corresponding to the stabilisation of sea level after 5 400 a BP; (3) a slight positive tendency in the sea level around 2 800 a BP recorded in the central part of the marsh; and (4) the wetland to a continental marsh environment. The sequential pattern for the evolution of wetlands in this estuarine area during the Holocene is fluvial facies-blackish schorre facies-slikke facies-blackish schorre facies-continental marsh facies. Characteristics of sedimentary facies distribution and evolution reveal that the development of Holocene salt marsh in this area was controlled by the sea-level change and tidal range. The

  14. Geochemical background values for trace elements in arable soils developed from sedimentary rocks of glacial origin. (United States)

    Czarnowska, K; Gworek, B


    The total content of trace elements was examined in some arable soils developed from boulder loam and silt formations of the Middle Poland and Baltic glaciations (62 profiles). Mean element concentrations calculated on the basis of chemical and statistical analyses were as follows: Mn = 322; Zn = 36; Cr = 30; Ni = 12.7; Pb = 10.3; Cu = 8.8; Co = 4.7; and Cd = 0.27 in mg kg(-1) of soil dry weight. The authors propose to accept these figures as the geochemical background values for soils derived from sedimentary rocks of glacial origin.

  15. Benchmarking of energy time series

    Energy Technology Data Exchange (ETDEWEB)

    Williamson, M.A.


    Benchmarking consists of the adjustment of time series data from one source in order to achieve agreement with similar data from a second source. The data from the latter source are referred to as the benchmark(s), and often differ in that they are observed at a lower frequency, represent a higher level of temporal aggregation, and/or are considered to be of greater accuracy. This report provides an extensive survey of benchmarking procedures which have appeared in the statistical literature, and reviews specific benchmarking procedures currently used by the Energy Information Administration (EIA). The literature survey includes a technical summary of the major benchmarking methods and their statistical properties. Factors influencing the choice and application of particular techniques are described and the impact of benchmark accuracy is discussed. EIA applications and procedures are reviewed and evaluated for residential natural gas deliveries series and coal production series. It is found that the current method of adjusting the natural gas series is consistent with the behavior of the series and the methods used in obtaining the initial data. As a result, no change is recommended. For the coal production series, a staged approach based on a first differencing technique is recommended over the current procedure. A comparison of the adjustments produced by the two methods is made for the 1987 Indiana coal production series. 32 refs., 5 figs., 1 tab.

  16. Nd Isotopic Composition and Material Source of Pre—and Post—Sinian Sedimentary Rocks in Xiushui Area,Jiangxi Province

    Institute of Scientific and Technical Information of China (English)

    沈谓洲; 刘继顺; 等


    Reported in this paper are the Nd isotopic compositions of the pre-Sinian and Sinian-Cambrian sedimentary rocks in the Xiushui area,Jiangxi Province.Significant differences are noticed between them in their Nd isotopic dompositions.As for the pre-Sinian lightly metmorphozed sedimentary rocks,143Nd/144Nd=0.512000-0.512214,CNd(T)=-8.04-9.99,and TDM=18332426Ma are suggested for the Sinian-Cambrian sedimentary rocks .These differences would reflect the diversity of material source for the sedimentary rocks deposited before and after the Sinian period.Mantle material ap-pears to have been involved in the formation of the pre-Sinian sedimentary rocks while the post-Sinian sedimentary rocks are composed mainly of recycled detritus from the continental crust.

  17. Models for dependent time series

    CERN Document Server

    Tunnicliffe Wilson, Granville; Haywood, John


    Models for Dependent Time Series addresses the issues that arise and the methodology that can be applied when the dependence between time series is described and modeled. Whether you work in the economic, physical, or life sciences, the book shows you how to draw meaningful, applicable, and statistically valid conclusions from multivariate (or vector) time series data.The first four chapters discuss the two main pillars of the subject that have been developed over the last 60 years: vector autoregressive modeling and multivariate spectral analysis. These chapters provide the foundational mater

  18. Fractal and Multifractal Time Series

    CERN Document Server

    Kantelhardt, Jan W


    Data series generated by complex systems exhibit fluctuations on many time scales and/or broad distributions of the values. In both equilibrium and non-equilibrium situations, the natural fluctuations are often found to follow a scaling relation over several orders of magnitude, allowing for a characterisation of the data and the generating complex system by fractal (or multifractal) scaling exponents. In addition, fractal and multifractal approaches can be used for modelling time series and deriving predictions regarding extreme events. This review article describes and exemplifies several methods originating from Statistical Physics and Applied Mathematics, which have been used for fractal and multifractal time series analysis.

  19. Time Series with Tailored Nonlinearities

    CERN Document Server

    Raeth, C


    It is demonstrated how to generate time series with tailored nonlinearities by inducing well- defined constraints on the Fourier phases. Correlations between the phase information of adjacent phases and (static and dynamic) measures of nonlinearities are established and their origin is explained. By applying a set of simple constraints on the phases of an originally linear and uncor- related Gaussian time series, the observed scaling behavior of the intensity distribution of empirical time series can be reproduced. The power law character of the intensity distributions being typical for e.g. turbulence and financial data can thus be explained in terms of phase correlations.

  20. Thermal conductivity of sedimentary rocks - selected methodological, mineralogical and textural studies

    Energy Technology Data Exchange (ETDEWEB)

    Midttoemme, Kirsti


    The thermal conductivity of sedimentary rocks is an important parameter in basin modelling as the main parameter controlling the temperature within a sedimentary basin. This thesis presents measured thermal conductivities, mainly on clay- and mudstone. The measured values are compared with values obtained by using thermal conductivity models. Some new thermal conductivity models are developed based on the measured values. The values obtained are less than most previously published values. In a study of unconsolidated sediments a constant deviation was found between thermal conductivities measured with a needle probe and a divided bas apparatus. Accepted thermal conductivity models based on the geometric mean model fail to predict the thermal conductivity of clay- and mudstone. Despite this, models based on the geometric mean model, where the effect of porosity is taken account of by the geometric mean equation, seem to be the best. Existing models underestimate the textural influence on the thermal conductivity of clay- and mudstone. The grain size was found to influence the thermal conductivity of artificial quartz samples. The clay mineral content seems to be a point of uncertainty in both measuring and modelling thermal conductivity. A good universal thermal conductivity model must include many mineralogical and textural factors. Since this is difficult, different models restricted to specific sediment types and textures are suggested to be the best solution to obtain realistic estimates applicable in basin modelling. 243 refs., 64 figs., 31 tabs.

  1. Use of passive seismic data to characterize sedimentary basins, an example from the Vienna Basin, Austria. (United States)

    Piana Agostinetti, N.; Bianchi, I.


    The analysis of passive seismic data leads a deeper understanding of the basin features in those areas that have been less explored via direct drilling. In this study, we use the Receiver Functions technique that constrain the presence of impedance contrasts at depth, caused by lithology changes, and seismic anisotropy, possibly related to fluid-filled cracks or alignment of orientated mineral grains. We present some examples from broadband seismic stations located in the Vienna basin, on the horst structures and in the deep depocenters, which characterize the sedimentary basin. Preliminary analysis of the high frequency (4Hz) RF data-set, show the presence of two close impedance contrasts, which presumably are related to the occurence of a thick sedimentary layer overlying a thinner limestone layer. Seismic anisotropy is recognized around the interface between sediments and limestones; the anisotropy is NE directed reflecting the NE alignment of the strike-slip fault system, which characterizes the area. The comparison of passive seismology with direct exploration improves the knowledge of the subsurface and adds new constraints on its geodynamical interpretation.

  2. Shell Bed Identification of Kaliwangu Formation and its Sedimentary Cycle Significance, Sumedang, West Java

    Directory of Open Access Journals (Sweden)

    Aswan Aswan


    Full Text Available DOI: 10.17014/ijog.v8i1.151Kaliwangu Formation cropping out around Sumedang area contains mollusk fossils dominated by gastropods and bivalves. In terms of sequence stratigraphy, each sedimentary cycle generally consists of four shell bed types: Early Transgressive Systems Tract (Early TST deposited above an erosional surface or sequence boundary, that is characterized by shell disarticulation, trace fossils, gravelly content, no fossil orientation direction, and concretion at the bottom; Late Transgressive Systems Tract (Late TST identified by articulated (conjoined specimen in its life position, that shows a low level abration and fragmentation, adult specimen with complete shells, and variation of taxa; Early Highstand Systems Tract (Early HST characterized by adult taxa that was found locally in their life position with individual articulation, juvenile specimens frequently occured; Late Highstand Systems Tract (Late HST determined as multiple-event concentrations, disarticulated shell domination, and some carbon or amber intercalation indicating terrestrial influence. Shell bed identification done on this rock unit identified nineteen sedimentary cycles.

  3. Sedimentary facies of Maastrichtian to Danian deposits in Amur River area, Russian Far East

    Institute of Scientific and Technical Information of China (English)

    Shigeyuki Suzuki; Abdul R. Ashraf; Hakuyu Okada


    Sedimentary facies of the Tsagayan Formation is distributed in the eastern Zeya-Bureya Basin has been analyzed. The formation is of the Maastrichtian to Danian in age and characterized by the cyclicity of the fining-upwards successions. Analysis of environmental changes during the K/T boundary is the focus of this study. Five facies have been identified: Facies A, thick and laterally extensive coarse-grained to medium-grained sandstone units, interpreted as channelfill deposits; Facies B, parallel-laminated to massive mudstone units interpreted as interchannel lakes and flood plain deposits; Facies C, sheet-like medium-grained to fine-grained sandstones interpreted as crevasse splay deposits;Facies D, coal to coaly mudstone beds interpreted as deposits ofpeatlands; Facies E, very poorly sorted sandy mudstone beds interpreted as debris flow deposits. Fluvial environments with the low-relief flat topography was inferred. A channel transported large volumes of clasts, and a flood basin with interchannel lakes and peatlands was deciphered. Any distinct change of sedimentary environments has not been identified throughout the Tsagayan Formation (including the K/T boundary). However, two beds of debris flow deposits were identified. The one occurs at the uppermost part of the lower Tsagayan Subformation and contains dinosaur fossils. The other is intercalated in the upper Tsagayan Subformation.

  4. Perturbation induced changes in substrate use by the blue mussel, Mytilus edulis, in sedimentary systems (United States)

    wa Kangeri, Arno K.; Jansen, Jeroen M.; Barkman, Barbara R.; Donker, Jasper J. A.; Joppe, Daniel J.; Dankers, Norbert M. J. A.


    For sessile benthic marine organisms adhesion to a stable substrate is important for survival. Sedimentary systems, however, generally lack stable surfaces. How sessile species like the mussel, Mytilus edulis, are able to achieve stability in unstable sediments is not fully understood. An intertidal mussel bed in the tidal flats in the Western portion of the Dutch Wadden Sea was selected to investigate adhesion behavior of M. edulis. Sampling was conducted along a hydrodynamic gradient along the Front-edge, Center and Back-edge of a mussel bed. Mussels along the bed edges were characterized by adhesion to fine shell debris and high numbers of byssus threads. Mussels in the center of the bed were characterized by adhesion to shells of living conspecifics and relatively low numbers of byssus threads. An experimental investigation to isolate the role of perturbation on adhesion strategies was carried out under laboratory conditions. Experimental results show that under perturbed conditions mussels developed increased numbers of byssus threads relative to mussels left unperturbed. Additionally, mussels subjected to perturbation preferentially adhered more frequently to fine shell debris while unperturbed mussels adhered more frequently to conspecifics. Results show that differentiation in adhesion strategy is driven by physical perturbation and mediated by bed density. The results also suggest that adhesion by mussels in a sedimentary environment is a selective process in which larger shell fragments and shells of conspecifics are the preferred substrate.

  5. A sedimentary paleomagnetic record of the upper Jaramillo transition from the Lantian Basin in China (United States)

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


    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.

  6. E/I corrected paleolatitudes for the sedimentary rocks of the Baja British Columbia hypothesis (United States)

    Krijgsman, Wout; Tauxe, Lisa


    Paleomagnetic inclinations from sediments of the western terranes of Canada are consistently too shallow for their reconstructed paleogeographic positions. Two contradicting explanations for these discrepancies are: (1) terranes have been displaced northward with respect to the stable American craton by several thousands of kilometres between the Late Cretaceous (˜ 75 Ma) and the Eocene (˜50 Ma) and (2) sedimentary inclination error has caused a shallow bias in the paleomagnetic directions. Here, we apply the elongation/inclination (E/I) method to paleomagnetic data sets from sedimentary rocks of supposedly allochtonous terranes of western North America to correct for inclination flattening. Our results indicate that the paleomagnetic directions from the continental Silverquick sediments (95-92 Ma) of southern British Colombia are not seriously affected by inclination error, because the magnetic signal most likely concerns a chemical remanent magnetisation (CRM). In contrast, the marine sediments of the Nanaimo Group (84-72 Ma) of Vancouver Island region appear seriously affected by inclination flattening ( f = 0.7) and the E/I corrected mean inclinations are about 9° steeper than the original data. We arrive at corrected inclinations/paleolatitudes of I** = 57°/ λ = 38°N for the Silverquick and I** = 55°/ λ = 36°N for the Nanaimo sediments. Our corrected paleolatitudes indicate that the Canadian terranes were indeed located adjacent to the Baja Californian margin during the Late Cretaceous, thus supporting the Baja BC hypothesis.

  7. Searching for tsunamis evidences on the Algarve (Southern Portugal) continental shelf sedimentary record (United States)

    Drago, Teresa; Silva, Pedro; Lopes, Ana; Magalhães, Vitor; Roque, Cristina; Rodrigues, Ana Isabel; Noiva, João; Terrinha, Pedro; Mena, Anxo; Francés, Guillermo; Kopf, Achim; Völker, David; Omira, Rachid; Baptista, Maria Ana


    Tsunami hazard assessment is important in order to prevent and/or minimize its effects, which is only possible if a complete and long record dataset of past events is available, allowing the estimation of their recurrence intervals. The knowledge of past tsunami events are based on instrumental, historical and geological records. Although instrumental and historical records are reliable sources they are limited in time. Geological records can give a much more extended reconstruction overview of thousand years, which can provide a good estimation of tsunami return periods. Most of the existing studies have been conducted onshore and only a few were based on offshore sedimentary record. These last ones, have the advantage to provide a more continuous and almost undisturbed records but the identification of tsunami sediments in marine environment require a multi-proxy approach in order to better identify the allochtonous layers/deposits and to differentiate them from storm deposits. In the context of ASTARTE project (FP7), five gravity and piston cores on the southern Portuguese continental shelf collected in 2008 and 2014 were studied. The methodology included XRF, MSCL, sedimentological and magnetic analyses. Preliminary results show some identifiable layers that may related with allochthonous sedimentary material, compatible with a genesis resulting from tsunami backwash sediment transport and deposition. Acknowledgments - Publication supported by project FCT UID/GEO/50019/2013 - Instituto Dom Luiz.

  8. Chicxulub ejecta plume: Influence of sedimentary target rock, volatiles and atmosphere (United States)

    Salge, T.

    Terrestrial impact structures provide evidence for cratering processes on planetary bodies with an atmosphere and volatiles in the target rocks. The target of the Chicxulub impact structure (˜180 km Ø) was composed of (1) a ˜3 km thick sedimentary and, thus, extremely volatile-rich target sequence, and (2) a crystalline silicate basement. The suevites of El Guayal ˜520 km SW from the crater centre and UNAM-7 near the crater rim recorded the distinct behaviour of sedimentary target rock, water and atmospheric interactions during ejecta emplacement. El Guayal: A ˜10 m thick suevite sequence contains shocked minerals, altered (to clay minerals) silicate melt and spherulitic carbonate melt particles. Fusion of silicate melt with carbonate induced calcite recrystallisation at >750°C. Release of CO2 is indicated by voids in silicate melt at the contact with calcite. Accretionary lapilli 350°C by slaking and from silicate melt particles. Conclusions: The following sequence of processes is proposed: (1) Vapour release changed ejecta distribution from ballistic to flow-like transport. (2) Ejecta plume collapse separated suevite from impactor material that had been lifted into the stratosphere. (3) Fusion of the different target components initiated a hot gas-driven lateral transport in a basal flow. (4) Accretionary lapilli formed in a coherent turbulent ash cloud. Acknowledgements: TS kindly thanks P. Claeys for providing samples, R. Tagle for PGE analyses and H. Stosnach for introduction to TXRF analyses.

  9. Determination of total sulfur content of sedimentary rocks by a combustion method (United States)

    Coller, M.E.; Leininger, R.K.


    Total sulfur has been determined in common sedimentary rocks by a combustion method. Sulfur contents range from 0.001 to 5.0%. Experiments show that the combustion method can be used in analyzing sedimentary rocks in which sulfur is present as sulfide, sulfate, or both. Pulverized samples from 0.100 to 0.500 gram in weight are used in this method. Each sample is placed in a No. 6 Leco combustion boat and covered with two fluxes: 0.50 gram of standard ingot iron and approximately 1.0 gram of 30-mesh granular tin. The boat with sample then is placed in the combustion tube of a Burrell Unit Package Model T29A tube furnace which is controlled at a temperature of 1310?? to 1320?? C. After the sample has been heated for 1 minute, oxygen is admitted at a rate of about 1 liter per minute. The sulfur dioxide formed is absorbed in a starch solution and is titrated with standard potassium iodate in a Leco sulfur determinator. Thirteen values obtained for National Bureau of Standards standard sample 1a, argillaceous limestone, range from 0.273 to 0.276% sulfur (certificate value 0.27% by calculation).

  10. Genetic data from algae sedimentary DNA reflect the influence of environment over geography. (United States)

    Stoof-Leichsenring, Kathleen R; Herzschuh, Ulrike; Pestryakova, Luidmila A; Klemm, Juliane; Epp, Laura S; Tiedemann, Ralph


    Genetic investigations on eukaryotic plankton confirmed the existence of modern biogeographic patterns, but analyses of palaeoecological data exploring the temporal variability of these patterns have rarely been presented. Ancient sedimentary DNA proved suitable for investigations of past assemblage turnover in the course of environmental change, but genetic relatedness of the identified lineages has not yet been undertaken. Here, we investigate the relatedness of diatom lineages in Siberian lakes along environmental gradients (i.e. across treeline transects), over geographic distance and through time (i.e. the last 7000 years) using modern and ancient sedimentary DNA. Our results indicate that closely-related Staurosira lineages occur in similar environments and less-related lineages in dissimilar environments, in our case different vegetation and co-varying climatic and limnic variables across treeline transects. Thus our study reveals that environmental conditions rather than geographic distance is reflected by diatom-relatedness patterns in space and time. We tentatively speculate that the detected relatedness pattern in Staurosira across the treeline could be a result of adaptation to diverse environmental conditions across the arctic boreal treeline, however, a geographically-driven divergence and subsequent repopulation of ecologically different habitats might also be a potential explanation for the observed pattern.

  11. A 60-year sedimentary record of natural and anthropogenic impacts on Lake Chenghai, China

    Institute of Scientific and Technical Information of China (English)

    Fengyu Zan; Shouliang Huo; Beidou Xi; Jingtian Zhang; Haiqing Liao; Yue Wang; Kevin M.Yeager


    Recent sediments from Lake Chenghai,China,were investigated at high temporal resolution to trace both natural and anthropogenic effects on the lake using total organic carbon (TOC),total nitrogen (TN),total phosphorus (TP),organic phosphorus (Po),inorganic phosphorus (Pi) and organic carbon and nitrogen stable isotopes (δ13Corg and δ15N) in a 137Cs-dated sediment core.The results indicated that the sedimentary record covers the last 60 years,during which the lake had undergone apparent changes in nutrient sources and productivity in response to nutrient loading.Prior to the late 1980s,the nutrient contents in sediments mainly originated from algae and lake productivity was relatively stable.Since the late 1980s,increasing TOC,TN and TP concentrations together with the change of δ13Corg and δ15N suggested anthropogenic perturbations in nutrient loading and lake productivity.Endogenic nutrients derived from algae and anthropogenic inputs were two important sources of sedimentary nutrients.The anthropogenic nutrients mainly originated from the discharge of industrial wastewater and artificial cultivation of Spirulina after the middle 1980s,and domestic wastewater discharged from Yongsheng County since 1993.

  12. Substantial stores of sedimentary carbon held in mid-latitude fjords (United States)

    Smeaton, Craig; Austin, William E. N.; Davies, Althea L.; Baltzer, Agnès; Abell, Richard E.; Howe, John A.


    Quantifying marine sedimentary carbon stocks is key to improving our understanding of long-term storage of carbon in the coastal ocean and to further constraining the global carbon cycle. Here we present a methodological approach which combines seismic geophysics and geochemical measurements to quantitatively estimate the total stock of carbon held within marine sediment. Through the application of this methodology to Loch Sunart, a fjord on the west coast of Scotland, we have generated the first full sedimentary carbon inventory for a fjordic system. The sediments of Loch Sunart hold 26.9 ± 0.5 Mt of carbon split between 11.5 ± 0.2 and 15.0 ± 0.4 Mt of organic and inorganic carbon respectively. These new quantitative estimates of carbon stored in coastal sediments are significantly higher than previous estimates. Through an area-normalised comparison to adjacent Scottish peatland carbon stocks, we have determined that these mid-latitude fjords are significantly more effective as carbon stores than their terrestrial counterparts. This initial work supports the concept that fjords are important environments for the burial and long-term storage of carbon and therefore should be considered and treated as unique environments within the global carbon cycle.

  13. Form From Projected Shadow (FFPS): An algorithm for 3D shape analysis of sedimentary particles (United States)

    Montenegro Ríos, Anibal; Sarocchi, Damiano; Nahmad-Molinari, Yuri; Borselli, Lorenzo


    In this paper we present a simple and effective method based on measuring the projected shadow of sedimentary particles by means of a digital image processing algorithm that enables the three principal axes of the particle to be determined from a single 2D color image. The method consists in projecting the shadow of the particle when it is resting on the maximum projection area (“c” axis pointing almost vertical, since in this configuration minimal distance from the center of mass to the floor is achieved minimizing the gravitational potential energy), by means of an oblique incident illumination system. Using HSL (hue-saturation-lightness) color space segmentation, two axes of the particle are measured directly from the maximum projected area. The length of the shadow provides the third axis of the particle. Multiple textured and colored sedimentary particles can be easily segmented from a green background and their corresponding shadows by means of a single space color transformation. This simple method enables the lengths of the three main axes of several particles to be determined at the same time without expensive equipment (the software is provided free by the authors). The axis lengths can span a broad range of sizes, and are measured with low experimental error (less than 5%).

  14. REE Geochemical Study of the Permian-Triassic Marine Sedimentary Environment in Guizhou Province

    Institute of Scientific and Technical Information of China (English)

    南君亚; 刘丛强; 周德全; 王筑明


    This paper deals with the REE geochemical characteristics of Permian-Triassic marine carbonate rocks in Guizhou Province. It is found that there are two broad categories of stratigraphic units in the region studied in accordance with their ∑ REE contents and REE distribution patterns: one is characterized by LREE enrichment and slight Ce depletion, with the REE distribution patterns similar to those of North American shales, and the other features relative HREE enrichment and relatively remarkable Ce depletion, with the REE distribution patterns close to those of pelagic sediments. In terms of their different ∑ REE contents, five types of stratigraphic units can be distinguished. Incorporation of detrital minerals, REE complexing capability, oxidation-reduction conditions of the media are the main factors affecting the REE composition and REE distribution patterns of marine carbonate rocks in the region studied. In the light of REE geochemical characteristics of carbonate rocks, coupled with sedimentary facies analysis, this paper discusses the characteristics of the Permian-Triassic marine sedimentary environment in Guizhou Province and its evolutional rules.

  15. Sulfur and carbon isotopic variations in Neoproterozoic sedimentary rocks from southern China

    Institute of Scientific and Technical Information of China (English)

    CHU Xuelei; ZHANG Qirui; ZHANG Tonggang; FENG Lianjun


    A new set of δ34Ssulfide, δ34Ssulfate and δ13Ccarbonate values has been reported from Neoproterozoic sedimentary rocks in southern China. The interglacial black shales of the Datangpo Fm. display higher δ34Ssulfide values with >+20‰ average, but the postglacial black shales from the Doushantuo Fm. show negative δ34Ssulfide values. However, the Jinjiadong Fm., the same post-glaciation as the Doushantuo Fm., has positive δ34Ssulfide values, implying that the δ34S value of sedimentary sulfides would be controlled by lithofacies and paleogeographic environments. The δ34Ssulfate values relative to δ13Ccarbonate were obtained by extraction of trace sulfate from the successive carbonate sequences in the Yangtze Gorges sections. A preliminary interpretation suggests that the oceanic environment may fluctuate dramatically at the post-glacial Doushantuo stage and, then, recover its stability at the Dengying stage on the basis of the high resolution δ34S and δ13C curves of seawater.

  16. Sedimentary structures of tidal flats: A journey from coast to inner estuarine region of eastern India

    Indian Academy of Sciences (India)

    A Chakrabarti


    Sedimentary structures of some coastal tropical tidal flats of the east coast of India, and inner estuarine tidal point bars located at 30 to 50 kilometers inland from the coast, have been extensively studied under varying seasonal conditions. The results reveal that physical features such as flaser bedding, herringbone cross-bedding, lenticular bedding, and mud/silt couplets are common to both the environments. In fact, flaser bedding and lenticular bedding are more common in the point bar facies during the monsoon months than in the coastal tidal flat environments. Interference ripples, though common in both the environments, show different architectural patterns for different environmental domains. Interference ripples with thread-like secondary set overriding the earlier ripple-form, resembling wrinkle marks, are the typical features in estuarine point bars near the high water region. Because structures which are so far considered as key structures for near-coastal tidal flats are common to both the environments, caution should be exercised for deciphering palaeo-environments, particularly for Proterozoic rocks, where one has to depend only on physical sedimentary structures.

  17. Structural geology of Amazonian-aged layered sedimentary deposits in southwest Candor Chasma, Mars (United States)

    Okubo, C.H.


    The structural geology of an outcropping of layered sedimentary deposits in southwest Candor Chasma is mapped using two adjacent high-resolution (1 m/pixel) HiRISE digital elevation models and orthoimagery. Analysis of these structural data yields new insight into the depositional and deformational history of these deposits. Bedding in non-deformed areas generally dips toward the center of west Candor Chasma, suggesting that these deposits are basin-filling sediments. Numerous kilometer-scale faults and folds characterize the deformation here. Normal faults of the requisite orientation and length for chasma-related faulting are not observed, indicating that the local sediments accumulated after chasma formation had largely ceased in this area. The cause of the observed deformation is attributed to landsliding within these sedimentary deposits. Observed crosscutting relationships indicate that a population of sub-vertical joints are the youngest deformational structures in the area. The distribution of strain amongst these joints, and an apparently youthful infill of sediment, suggests that these fractures have been active in the recent past. The source of the driving stress acting on these joints has yet to be fully constrained, but the joint orientations are consistent with minor subsidence within west Candor Chasma.

  18. A sugar biomarker proxy for assessing terrestrial versus aquatic sedimentary input (United States)

    Hepp, Johannes; Rabus, Max; Laforsch, Christian; Anhäuser, Tobias; Glaser, Bruno; Zech, Michael


    Lake sediments are valuable, often continuous and potentially high resolution archives for studying past climate changes. Thereby, one of the crucial questions is often whether the origin of the organic matter in lake sediments is allochthonous (terrestrial) or autochthonous (aquatic). Here we present patterns of neutral sugars of various plants and algae species to answer the question whether the deoxyhexoses (fucose, rhamnose) to pentoses (arabinose, xylose) ratio can serve as a proxy for aquatic versus terrestrial sedimentary lake input, respectively. Our sugar pattern results show that the fucose + rhamnose content plotted against arabinose and xylose in a ternary diagram can be used to distinguish between algae and other (namely aquatic plants, emergent plant, and terrestrial plants) sugar sources. This finding is confirmed by a compilation with sugar data from the literature. Mosses plot within the range of algae. Although the (fucose + rhamnose)/(arabinose + xylose) ratio yields some overlapping between algae and soil/litter samples, we recommend this ratio, particularly when applied within a multiproxy approach, as promising proxy for distinguishing between aquatic vs. terrestrial organic matter in sedimentary archives. Regarding the sugar concentrations of the investigated samples, emergent plants show the highest values as well as the highest variability. Mosses, aquatic plants and algae yield lower sugar concentrations comparable to those of terrestrial plants.

  19. Modern Pearl River Delta and Permian Huainan coalfield, China: A comparative sedimentary facies study (United States)

    Suping, P.; Flores, R.M.


    Sedimentary facies types of the Pleistocene deposits of the Modern Pearl River Delta in Guangdong Province, China and Permian Member D deposits in Huainan coalfield in Anhui Province are exemplified by depositional facies of anastomosing fluvial systems. In both study areas, sand/sandstone and mud/mudstone-dominated facies types formed in diverging and converging, coeval fluvial channels laterally juxtaposed with floodplains containing ponds, lakes, and topogenous mires. The mires accumulated thin to thick peat/coal deposits that vary in vertical and lateral distribution between the two study areas. This difference is probably due to attendant sedimentary processes that affected the floodplain environments. The ancestral floodplains of the Modern Pearl River Delta were reworked by combined fluvial and tidal and estuarine processes. In contrast, the floodplains of the Permian Member D were mainly influenced by freshwater fluvial processes. In addition, the thick, laterally extensive coal zones of the Permian Member D may have formed in topogenous mires that developed on abandoned courses of anastomosing fluvial systems. This is typified by Seam 13-1, which is a blanket-like body that thickens to as much as 8 in but also splits into thinner beds. This seam overlies deposits of diverging and converging, coeval fluvial channels of the Sandstone D, and associated overbank-floodplain deposits. The limited areal extent of lenticular Pleistocene peat deposits of the Modern Pearl River Delta is due to their primary accumulation in topogenous mires in the central floodplains that were restricted by contemporaneous anastomosing channels.

  20. Sedimentary environment of Ediacaran glacigenic diamictite in Guozigou of Xinjiang,China

    Institute of Scientific and Technical Information of China (English)

    DING HaiFeng; MA DongSheng; YAO ChunYan; SHU LiangShu


    The Talisayi Formation found in the Guozigou region on the southern side of Sayram Lake of Xinjiang,China is a Neoproterozoic glacigenic diamictite succession that has not been adequately researched.According to its isotopic geochronology and regional stratigraphic correlation,the Talisayi Formation is equivalent to the Ediacaran glacial sediments. The present paper provides the geochemical data of the Talisayi Formation that reveals the tectonic setting and sedimentary environment in this area during the Ediacaran period. The oxides of Si,K,Na and AI and their ratios of matrix materials from glacigenic diamictites and bulk rock of siltstone and argillaceous siltstones indicate that the sedimentary environment of this formation evolved from a tectonically active region to a passive continental margin.Values of CIA (carbonate-corrected Chemical Index of Alteration) ranging from 54 to 74 show a low-middle weathering action under a glacial environment. Total organic carbon (TOC),V/Cr,Ni/Co and U/Th ratios suggest that the sediments deposited in shallow water with an oxic and weak hydrodynamic condition. There is an abrupt rise in TOC,V/Cr,Ni/Co and U/Th ratios respectively in the overlying Lower Cambrian dolomitic limestones and in the bottom of Talisayi Formation,indicating a rapidl increase in biologic productivity and a variation in redox conditions,which was probably caused by seawater mixing of deep anoxic water and surface oxic water.

  1. Geochemical inputs for hydrological models of deep-lying sedimentary units: Loss of mineral hydration water (United States)

    Graf, D. L.; Anderson, D. E.


    Hydrological models that treat phenomena occurring deep in sedimentary piles, such as petroleum maturation and retention of chemical and radioactive waste, may require time spans of at least several million years. Many input quantities classically treated as constants will be variables on this time scale. Models sophisticated enough to include transport contributions from such processes as chemical diffusion, mineral dehydration and shale membrane behavior require considerable knowledge about regional geological history as well as the pertinent mineralogical and geochemical relationships. Simple dehydrations such as those of gypsum and halloysite occur at sharply-defined temperatures but, as with all mineral dehydration reactions, the equilibrium temperature is strongly dependent on the pore-fluid salinity and degree of overpressuring encountered in the subsurface. The dehydrations of analcime and smectite proceed by reactions involving other sedimentary minerals. The smectite reaction is crystallographically complex, yielding a succession of mixed-layered illite/smectites, and on the U.S.A. Gulf of Mexico coast continues over several million years at a particular stratigraphic interval.

  2. Paleogeomorphy, provenance system and sedimentary system of the Dongying formation in the Qikou sag

    Institute of Scientific and Technical Information of China (English)

    WANG Hua; HUANG Chuan-yan; ZHAO Shu-e; YAN De-tian; BAI Yun-feng; XIANG Xue-mei; CHEN Si; XIA Cun-yin; LIAO Ji-hua


    Reconstructed synsedimentary paleogeomorpholgy is an effective method in predicting the distribution of sandbodies and can provide valid evidence in the search for reservoirs. Based on a synsedirnentary paleogeomorpholgy reconstruction of the third member of the Dongying formation (Ed3) in the Qikou sag, the basic paleogeomorphic characteristics of Ed3 are described and the spatial distributions of denudation and subsidence areas are discussed. Key boundary faults controlling the deposition of impor-tant sediment bodies are proposed and the interrelations among faulted slope-break belts or flexure belts, intra-depression uplifts and sags, sediment sources and sediments input points have been investigated. Furthermore, the spatial distributions of the depo-center, subsidence centers and a sedimentary system have been determined. Our results are beneficial in the search for prominent reservoirs in petroleum exploration. Therefore, they are of important theoretical and practical value in discussing the compilation techniques of syndepositional paleogeomorphology, in recognizing paleogeomorphic characteristics and the coupling analysis of provenance and sedimentary systems.

  3. Provenance and palaeogeographic implications of Eocene-Oligocene sedimentary rocks in the northwestern Basin and Range (United States)

    Egger, A.E.; Colgan, J.P.; York, C.


    A thick sequence of uppermost Eocene to lower Oligocene volcaniclastic and sedimentary rocks is exposed at the base of the Warner Range in northeastern California. This isolated exposure provides insight into the palaeogeographic setting of the northwestern Basin and Range during this time period. Significant thinning of the unit over 35km of lateral exposure and predominantly volcanic clast compositions suggest that the sequence was deposited in an alluvial plain adjacent to a volcanic arc. Palaeocurrent indicators in the conglomerates define a NNE transport direction. Detrital zircon analysis on coarse sandstones and dating of individual granite cobbles show a range of ages consistent with a local, volcanic source area primarily from the SSW with some far-travelled input from northern Nevada; the far-travelled component increases in influence as the unit thins to the north. Comparison with other sedimentary sequences of Eocene age and integration with palaeofloral and geophysical data help to define drainage divides, and suggest that this sequence accumulated in a relatively isolated, intra-arc basin. This localized accumulation differs markedly from contemporaneous drainages to the south that transported material westwards from central Nevada to the palaeoshoreline, and suggests that ongoing volcanism had a strong influence on palaeogeography in this region during the Eocene and Oligocene.

  4. Genetic data from algae sedimentary DNA reflect the influence of environment over geography (United States)

    Stoof-Leichsenring, Kathleen R.; Herzschuh, Ulrike; Pestryakova, Luidmila A.; Klemm, Juliane; Epp, Laura S.; Tiedemann, Ralph


    Genetic investigations on eukaryotic plankton confirmed the existence of modern biogeographic patterns, but analyses of palaeoecological data exploring the temporal variability of these patterns have rarely been presented. Ancient sedimentary DNA proved suitable for investigations of past assemblage turnover in the course of environmental change, but genetic relatedness of the identified lineages has not yet been undertaken. Here, we investigate the relatedness of diatom lineages in Siberian lakes along environmental gradients (i.e. across treeline transects), over geographic distance and through time (i.e. the last 7000 years) using modern and ancient sedimentary DNA. Our results indicate that closely-related Staurosira lineages occur in similar environments and less-related lineages in dissimilar environments, in our case different vegetation and co-varying climatic and limnic variables across treeline transects. Thus our study reveals that environmental conditions rather than geographic distance is reflected by diatom-relatedness patterns in space and time. We tentatively speculate that the detected relatedness pattern in Staurosira across the treeline could be a result of adaptation to diverse environmental conditions across the arctic boreal treeline, however, a geographically-driven divergence and subsequent repopulation of ecologically different habitats might also be a potential explanation for the observed pattern.

  5. Physical and chemical environments of abnormal vitrinite reflectance evolution in the sedimentary basins

    Institute of Scientific and Technical Information of China (English)

    QIU Nansheng; WANG Weixiao; XIE Mingju


    Based on the tested data of pressure and vitrinitere flectance of some wells in sedimentary basins, abnormal high pressure is regarded as not the only factor to retard the increase of vitrinite reflectance (Ro). Apart from the types of the organic matter, the physical environment (temperature and pressure) and chemical environment (fluid compositionand inorganic elements) will result in the abnormal vitrinite reflectance values in the sedimentary basins. This paper tested trace elements and vitrinite reflectance data from the the abnormal high pressure and normal pressure strata pro-files, respectively, and found that the acidic and lower salinity starta are favorable for the increase of Ro. By discussing the corresponding relationship between the contents of some trace elements in the mudstone and the vitrinite reflectance values, the typical trace elements were found to suppress and/or catalyze the vitrinite reflectance of organic matter, while the elements of Ca, Mn, Sr, B, Ba and P may result in the retardation of Ro. However, elements of Fe, Co, Zn, Ni and Rb may catalyze the organic matter maturation. This study is conductive to the organic maturation correction, oil and gas assessment and thermal history reconstruction by the paleothermometry.

  6. Sedimentary environmental change induced from late Quaternary sea-level change in the Bonaparte Gulf, northwestern Australia (United States)

    Ishiwa, Takeshige; Yokoyama, Yusuke; Miyairi, Yosuke; Ikehara, Minoru; Obrochta, Stephen


    Low-latitude continental shelves, mixed siliciclastic-carbonate sedimentary systems, provide an understanding of sedimentary environments driven by paleoclimatological processes. The Bonaparte Gulf, northwestern Australian continental shelf, is among the widest in the world, ranging to 500 km, with shallow carbonate terraces and platforms that were exposed during periods of lower sea level. The dominant sediments type switches between carbonate and siliciclastic over a sea-level cycle. However, the mechanism of sedimentary environmental change in the Bonaparte Gulf is not clearly understood. Here, we present a record of sedimentary environmental change from ca. 24 to 35 ka that is related to sea-level variability and exposure of carbonate terraces and platforms. Multi-proxy data from a marine sediment core show a sea-level change induced switch in sedimentary environment from siliciclastic to carbonate-dominated sedimentation during the last glaciation. Radiocarbon ages constrain the timing of this switch to ca. 26 ka, associated with a local sea-level fall of -90 m.

  7. Assessing automated image analysis of sand grain shape to identify sedimentary facies, Gran Dolina archaeological site (Burgos, Spain) (United States)

    Campaña, I.; Benito-Calvo, A.; Pérez-González, A.; Bermúdez de Castro, J. M.; Carbonell, E.


    Gran Dolina is a cave (Sierra de Atapuerca, Spain) infilled by a 25 m thick sedimentary record, divided into 12 lithostratigraphic units that have been separated into 19 sedimentary facies containing Early and Middle Pleistocene hominin remains. In this paper, an automated image analysis method has been used to study the shape of the sedimentary particles. Since particle shape is interpreted as the result of sedimentary transport and sediment source, this study can provide valuable data about the sedimentological mechanism of sequence formation. The shape of the sand fraction in 73 samples from Gran Dolina site and Sierra de Atapuerca was analyzed using the Malvern Morphologi G3, an advanced particle characterization tool. In this first complete test, we used this method to the published sequence of Gran Dolina, defined previously through field work observations and geochemical and textural analysis. The results indicate that this image analysis method allows differentiation of the sedimentary facies, providing objective tools to identify weathered layers and measure the textural maturity of the sediments. Channel facies have the highest values of circularity and convexity, showing the highest textural maturity of particles. On the other hand, terra rossa and debris flow samples show similar values, with the lowest particle maturity.

  8. Sea-floor morphology and sedimentary environments in western Block Island Sound, offshore of Fishers Island, New York (United States)

    McMullen, Katherine Y.; Poppe, Lawrence J.; Danforth, William W.; Blackwood, Dann S.; Winner, William G.; Parker, Castle E.


    Multibeam-bathymetric and sidescan-sonar data, collected by the National Oceanic and Atmospheric Administration in a 114-square-kilometer area of Block Island Sound, southeast of Fishers Island, New York, are combined with sediment samples and bottom photography collected by the U.S. Geological Survey from 36 stations in this area in order to interpret sea-floor features and sedimentary environments. These interpretations and datasets provide base maps for studies on benthic ecology and resource management. The geologic features and sedimentary environments on the sea floor are products of the area’s glacial history and modern processes. These features include bedrock, drumlins, boulders, cobbles, large current-scoured bathymetric depressions, obstacle marks, and glaciolacustrine sediments found in high-energy sedimentary environments of erosion or nondeposition; and sand waves and megaripples in sedimentary environments characterized by coarse-grained bedload transport. Trawl marks are preserved in lower energy environments of sorting and reworking. This report releases the multibeam-bathymetric, sidescan-sonar, sediment, and photographic data and interpretations of the features and sedimentary environments in Block Island Sound, offshore Fishers Island.

  9. Chemostratigraphy of early Neoproterozoic sedimentary rocks of Yenisei ridge (Siberia, Russia) (United States)

    Vishnevskaya, Irina; Pisareva, Natalia; Kanygina, Nadejda; Proshenkin, Artem


    One of the biggest Proterozoic sedimentary basins in Russia is around the Siberian platform. This study about little part of them - Neoproterozoic sedimentary rocks of Yenisei ridge (Southwestern margin of Siberian Platform). Thise geological structure is ancient and very difficult for reaserch. It is a collage of different blocks: volcanic arcks, ophiolite complexes and sedimentary rocks of various ages and degrees of metamorphism. Sedimentary complexes of Siberian platform are outcropping along Angara River and its tributary. Neoproterozoic ones are presented by terrigenous-carbonate rocks of Tungusik and Oslyan groups. Despite the long study history of the area is still controversial question of time of formation of these rocks. As determination of the age of Precambrian sedimentary rocks is very difficult, Sr isotopic chemostratigraphy appears to be the only approach to establish the age of carbonate sequences. All Rb-Sr author's data was investigated by the method of selective dissolution with the preliminary removal of epigenetic carbonate phases. The isotope dilution method with mixed 87Rb + 84Sr spike was used to determine Rb and Sr concentrations in both fractions on the MI 1201AT mass spectrometer. Sr isotope ratios were measured on the Finnigan MAT-262 (BAC CU, Irkutsk, Russia) and Triton Plus (IGG UB RAS, Ekaterinburg, Russia). The C-O isotopic composition in carbon samples was measured on the Finnigan MAT-253 equipment. The main criteria for integrity were correlations of impurity-elements (Mn, Fe, Sr) and stable isotopes (C, O) with each other. The less altered rocks of the Tungusik Group are characterized by 87Sr/86Sr ratio of 0.7055-0.7058, and wide variations in the δ13CPDB values from 0 to +5o [1]. The primary 87Sr/86Sr of Dashka Formation (Oslyan Group) is 0.7057 - 0.7060 and δ13CPDB value varies in interval 3.7-4.3o like in upper part of Tungusik Group. High positive values of δ13CPDB indicate that carbonates had accumulated in warm sea

  10. The Harvey lectures, Series 82

    Energy Technology Data Exchange (ETDEWEB)

    Botstein, D.; Cech, T.R.; Hille, B.; Lodish, H.F.; Majerus, P.W.


    The Harvey Lecture Series is published annually and provides reviews of research topics in the biomedical sciences. Eight lectures by investigators are included in the volume representing the most recent work in the major laboratories.

  11. Eisenstein series for SL(2)

    Institute of Scientific and Technical Information of China (English)

    KUDLA; Stephen; S.


    This paper gives explicit formulas for the Fourier expansion of general Eisenstein series and local Whittaker functions over SL2.They are used to compute both the value and derivatives of these functions at critical points.

  12. Some general random Taylor series

    Institute of Scientific and Technical Information of China (English)

    孙道椿; 余家荣


    Kahane has studied the value distribution of Gauss-Taylor series where is a complex Gauss sequence and The value distribution of more general random Taylor series is considered, where {Xn} is a sequence of real or complex random variables of independent, symmetric and equally distributed with finite non-zero fourth moment (the classical Gauss, Steinhaus and Rademacher random variables are special cases of such variables). First a theorem on the growth of characteristic functions is proved by a method which is completely different from Kahane’s. Then it is applied to proving that the range of general random Taylor series is almost surely dense everywhere in the complex plane and that if the random variable is bounded and continuous, the random series surely has no finite Nevanlinna deficient value.

  13. The Peano-Baker series

    CERN Document Server

    Baake, Michael


    This note reviews the Peano-Baker series and its use to solve the general linear system of ODEs. The account is elementary and self-contained, and is meant as a pedagogic introduction to this approach, which is well known but usually treated as a folklore result or as a purely formal tool. Here, a simple convergence result is given, and two examples illustrate that the series can be used explicitly as well.

  14. Statistical characterisation and stochastic parameterisation of sedimentary geological formations on their reaction capacity for sustainable groundwater quality management (United States)

    Griffioen, J.; Vermooten, S.; Keijzer, T.; Bakr, M.; Valstar, J.


    The fate of contaminants in groundwater aquifers is determined by the buffering capacity of those aquifers together with the composition of inflowing groundwater. A nationwide characterisation of the environmental geochemistry of the shallow subsurface (down to 30 m below surface) has been started in the Netherlands. This covers: 1. the reaction capacity of sediments as buffer for contamination, and 2. typical elemental composition of geological formations and the association between trace elements and major minerals. For this purpose, the Netherlands is subdivided into 27 so-called geotop regions each having a unique geological build-up of the shallow subsurface. Here, four types are recognised based on vertical hydrogeological build-up. The regions are statistically characterised on their geochemical composition using combinations of lithological class and geological formation as strata. The statistical data are subsequently coupled with a geological voxel model of the subsurface to stochastically parameterise the geological units on reaction capacity. This combined approach will be illustrated for the Dutch province Zeeland. Reaction capacity is considered as a series of geochemical characteristics that control acid/base condition, redox condition and sorption capacity. Five primary reaction capacity variables are characterised: 1. pyrite, 2. non-pyrite, reactive iron (oxides, siderite and glauconite), 3. clay fraction, 4. organic matter and 5. Ca-carbonate. Important reaction capacity variables that are determined by more than one solid compound are also deduced: 1. potential reduction capacity (PRC) by pyrite and organic matter, 2. cation-exchange capacity (CEC) by organic matter and clay content, 3. carbonate buffering upon pyrite oxidation (CPBO) by carbonate and pyrite. A statistical investigation of several hunderds of sediment analyses is performed that provides the geochemical properties of the sediments. Here, classification based on sedimentary facies

  15. Correlation of sedimentary units from grain-size and mineralogic analyses as a tool for constraining trench interpretations in palaeoseismology (United States)

    Ezquerro, Lope; Liesa, Carlos L.; Simón, José L.; Arlegui, Luis E.; Luzón, Aránzazu; Lafuente, Paloma


    In palaeoseismological trench studies, precise correlation of sedimentary units between fault blocks has an unquestionable value for accurately inferring the amounts of coseismic displacement and hence for assessing seismic hazard. A methodology based on laser analysis of particle size and mineralogic composition by X-ray diffraction is proposed in order to strengthen the correlation of sedimentary units in a trench excavated across the Concud Fault (central Iberian Chain, Spain). The surveyed sediments show sharp and multiple lateral facies changes, as well as inconsistent optically stimulated luminescence (OSL) ages. The results reinforce the correlation based on field inspection of lithologic and sedimentologic features. Moreover, they allow interpretation of rejuvenation of OSL ages of samples in the upthrown fault block, which has been attributed to partial erosion of sedimentary units, as evidenced by their smaller thickness and erosive boundaries. The correlated units are then used to estimate coseismic displacements for three palaeoseismic events.

  16. Palynostratigraphy and sedimentary facies of Middle Miocene fluvial deposits of the Amazonas Basin, Brazil (United States)

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


    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

  17. Trace metals partitioning among different sedimentary mineral phases and the deposit-feeding polychaete Armandia brevis

    Energy Technology Data Exchange (ETDEWEB)

    Díaz-de-Alba, Margarita [Department of Analytical Chemistry, Institute of Biomolecules (INBIO), Faculty of Sciences, CEI-MAR, University of Cadiz, Campus Rio S. Pedro, E-11510, Puerto Real, Cadiz (Spain); Huerta-Diaz, Miguel Angel, E-mail: [Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, Campus Ensenada, Km. 103 Carr. Tijuana-Ensenada, Ensenada 22800, Baja California (Mexico); Delgadillo-Hinojosa, Francisco [Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, Campus Ensenada, Km. 103 Carr. Tijuana-Ensenada, Ensenada 22800, Baja California (Mexico); Hare, Landis [Centre Eau Terre Environnement, 490, rue de la Couronne, Québec, Québec G1K 9A9 (Canada); Galindo-Riaño, M. Dolores [Department of Analytical Chemistry, Institute of Biomolecules (INBIO), Faculty of Sciences, CEI-MAR, University of Cadiz, Campus Rio S. Pedro, E-11510, Puerto Real, Cadiz (Spain); Siqueiros-Valencia, Arturo [Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, Campus Ensenada, Km. 103 Carr. Tijuana-Ensenada, Ensenada 22800, Baja California (Mexico)


    Trace metals (Cd, Co, Cu, Fe, Mn, Ni, Pb, Zn) were determined in two operationally defined fractions (HCl and pyrite) in sediments from Ensenada and El Sauzal harbors (Mexico). The HCl fraction had significantly higher metal concentrations relative to the pyrite fraction in both harbors, underlining the weak tendency of most trace metals to associate with pyrite. Exceptionally, Cu was highly pyritized, with degrees of trace metal pyritization (DTMP) > 80% in both harbors. Dissolved Fe flux measurements combined with solid phase Fe sulfide data indicated that 98 mt of Fe are precipitated as iron sulfides every year in Ensenada Harbor. These Fe sulfides (and associated trace metals) will remain preserved in the sediments, unless they are perturbed by dredging or sediment resuspension. Calculations indicate that dredging activities could export to the open ocean 0.20 ± 0.13 to (0.30 ± 0.56) × 10{sup 3} mt of Cd and Cu, respectively, creating a potential threat to marine benthic organisms. Degrees of pyritization (DOP) values in Ensenada and El Sauzal harbors were relatively low (< 25%) while degrees of sulfidization (DOS) were high (~ 50%) because of the contribution of acid volatile sulfide. DOP values correlated with DTMP values (p ≤ 0.001), indicating that metals are gradually incorporated into pyrite as this mineral is formed. Significant correlations were also found between DTMP values and − log(K{sub sp(MeS)}/K{sub sp(pyr)}) for both harbors, indicating that incorporation of trace metals into the pyrite phase is a function of the solubility product of the corresponding metal sulfide. The order in which elements were pyritized in both harbors was Zn ≈ Mn < Fe < Cd ≈ Pb < Ni ≈ Co < < Cu. Lastly, a strong correlation (r{sup 2} = 0.87, p < 0.01) was found between average reactive trace metal concentrations and metal concentrations measured in Armandia brevis (a deposit-feeding Opheliid polychaete), suggesting that these labile sedimentary metals are

  18. Recording of climate and diagenesis through fossil pigments and sedimentary DNA at Laguna Potrok Aike, Argentina (United States)

    Vuillemin, A.; Ariztegui, D.; Leavitt, P. R.; Bunting, L.; Pasado Science Team


    Aquatic sediments record past climatic conditions while providing a wide range of ecological niches for microorganisms. Although marine sedimentary microbial assemblages are often defined by their surrounding geochemical conditions, the influence of environmental features upon microbial development and post-depositional survival remains largely unknown in the lacustrine realm. Due to long-term microbial activity, the composition of environmental DNA can be expected to evolve with sediment depth and over time and therefore should reflect both ancient and extant microbial populations, but this hypothesis has rarely been tested using a multiproxy approach. Here geomicrobiological and phylogenetic analyses of a Patagonian maar lake were used to indicate that the different sedimentary microbial assemblages derive from specific lacustrine regimes during defined climatic periods. Two well defined climatic intervals whose sediments harboured active microbial populations and measurable ATP were sampled for a comparative environmental study based on fossil pigments and 16S rRNA gene sequences. Bacterial and archaeal 16S rRNA gene sequences recovered from the Holocene record revealed a microbial community adapted to subsaline conditions actively producing methane during organic matter degradation. These characteristics were associated with sediments resulting from endorheic lake conditions with high evaporative stress and concomitant high algal productivity. Moreover, archaeal clone libraries established throughout the Holocene record indicate an age-related stratification of these populations, consistent with a gradual use of organic substrates after deposition. In contrast, sulphate-reducing bacteria and lithotrophic Archaea were predominant in sediments dated from the Last Glacial Maximum, in which pelagic clays alternated with fine volcanic material characteristic of a lake level highstand and freshwater conditions, but reduced water column productivity. These patterns

  19. Sedimentary changes on the Southeastern Brazilian upper slope during the last 35,000 years

    Directory of Open Access Journals (Sweden)

    Michel M. Mahiques


    Full Text Available A first evaluation of the sedimentary changes, including accumulation of inorganic and organic carbon on the upper slope off Southeastern Brazil under different climatic conditions, based on the analysis of a sedimentary core, is here presented. Results indicate that sedimentation rate as well sedimentary characteristics, including the nature of the organic carbon deposited during the LGM (Last Glacial Maximum, were different from the present deposition, indicating higher primary productivity during the LGM, to be accounted for by the higher values of marine organic carbon. Nevertheless, the higher values of Accumulation Rate of calcium carbonate and organic carbon can be credited to the higher values of the sedimentation rates. Conditions prevailing during Isotope Stage 3 may be considered intermediate as between the LGM and the present day. The conditions for a higher primary productivity associated with the deposition of finer terrigenous sediments may be explained as a response to the off shoreward displacement of the main flow of the Brazil Current.Este trabalho apresenta uma primeira avaliação das mudanças sedimentares, incluindo a acumulação de carbono orgânico e inorgânico, no talude continental superior do Brasil, sob diferentes condições climáticas, baseadas em análises de um testemunho. Os resultados indicam que a taxa de sedimentação, assim como as características sedimentares, incluindo a natureza do carbono orgânico depositado durante o UMG (Último Máximo Glacial, foram diferentes dos processos deposicionais atuais, indicando maior produtividade primária durante o UMG, como determinado pelos maiores valores de carbono orgânico marinho. Entretanto, os maiores valores de Taxa de Acumulação de carbonato de cálcio e carbono orgânico podem ser creditados aos valores mais altos de taxas de sedimentação. As condições prevalentes durante o Estágio Isotópico 3 podem ser consideradas intermediárias entre o UMG e

  20. Sedimentary pigments in the western Barents Sea: A reflection of pelagic-benthic coupling? (United States)

    Morata, Nathalie; Renaud, Paul E.


    Local pelagic and sympagic primary production are usually the base of the Arctic food webs, and can be the main inputs of organic matter to the benthos. In order to characterize the major sources of production and understand the fate of organic matter to the benthos, water-column, ice, and sedimentary pigments of the Barents Sea were studied by HPLC analysis at 12 stations during the summer 2003, summer 2004, and spring 2005, in the framework of the CABANERA project. Chlorophyll a (chl a) concentration in surface sediments correlated significantly with total chl a integrated throughout the water-column as well as the chl a fluxes measured at 1 and 90 m water depth. This suggests that local water-column and ice-associated algae production are the main sources of fresh organic matter to the benthos. In the sediment, water-column, and ice, the major accessory pigment found was fucoxanthin, the marker pigment of diatoms, particularly dominant in spring. In summer, chlorophyll b, a marker of green algae, was found in stations influenced by Arctic waters, while 19'-hex-fucoxanthin, a marker of prymnesiophytes, was found in stations influenced by Atlantic water. The source of organic matter inputs to the benthos is thus highly dependent of the water masses influences in the summer. The ratio of sedimentary chl a to total phaeopigments (chl a/phaeo) was higher in the spring, and the total of phaeopigments in the sediment was correlated with water-column phaeopigments and with sedimentary phaeophorbide a, a pigment typical of grazing by zooplankton. This suggests that in the summer, organic matter reaching the sediment already has been degraded through grazing, while in spring, more fresh material reaches the sediment. The chl a/phaeo ratio was correlated with benthic oxygen demand measured by other researcher in this project, suggesting the importance of the quality of the organic matter reaching the sediment for benthos activities. Our results confirm a close pelagic

  1. On the hydraulic characterizing of the quaternary sedimentary media of Bucharest City (United States)

    Amine Boukhemacha, Mohamed; Radu Gogu, Constantin; Serpescu, Irina; Gaitanaru, Dragos; Diaconescu, Alin; Priceputu, Adrian; Bica, Ioan; Brusten, Alexandru


    The hydraulic conductivity of geological media is a complex property to describe. This property can change many orders of magnitude over short distances as it is even considered to be dependent of the observation scale. Current trends of hydrogeology studies show an increase need of geospatial databases. Such databases usually store, in a coherent and logical structure, different types of information (such as geological hard/soft data, hydraulic properties of the geological facies, stress factors and boundary conditions). An optimal use of the geospatial databases for groundwater flow modeling for example, will require exploring extended possible uses of the stored information. For clastic sedimentary rocks, considering that measured values of the hydraulic properties are not always available simultaneously with lithological data, it will be practical to estimate or to predict a domain of variation of such properties on the basis of the lithological description. Consequently, indirectly estimated values or variation domains of the hydraulic conductivity should be deduced by using the lithological description data. Such values can be used to verify models parameterization obtained by applying inverse calibration techniques or will reduce manual calibration efforts by providing narrow trial and error intervals. The present study gives an approach that can be used to characterize sedimentary media in terms of hydraulic conductivity on the basis of the lithological description. This relies on the results of a statistical analysis of a set of 647 well specific capacity tests conducted in quaternary clastic rocks (southeastern part of Romania) combined with a lithological description adaptation procedure. The analysis of hydraulic tests allowed the determination of statistical parameters of the hydraulic conductivity of basic lithological materials. As for the lithological description adaptation procedure, it transforms a complex lithology description into a set of basic

  2. Sedimentary organic matter variations in the Chukchi Borderland over the last 155 kyr

    Directory of Open Access Journals (Sweden)

    S. F. Rella


    Full Text Available Knowledge on past variability of sedimentary organic carbon in the Arctic Ocean is important to assess natural carbon cycling and transport processes related to global climate changes. However, the late Pleistocene oceanographic history of the Arctic is still poorly understood. In the present study we show sedimentary records of total organic carbon (TOC, C/N and CaCO3 from a piston core recovered from the northern Northwind Ridge in the far western Arctic Ocean, a region potentially sensitively responding to past variability in surface current regimes and sedimentary processes such as coastal erosion. An age model based on correlation of our CaCO3 record with the benthic δ18O stack, supplemented by lithological constraints, suggests that the piston core records paleoenvironmental changes of the last 155 kyr. According to this age model, TOC and C/N show orbital-scale increases and decreases that can be respectively correlated to the waxing and waning of large ice sheets dominating the Eurasian Arctic, suggesting advection of fine suspended matter derived from glacial erosion to the Northwind Ridge by eastward flowing intermediate water and/or surface water and sea ice during cold episodes of the last two glacial-interglacial cycles. At millennial scales, increases in TOC and C/N appear to correlate to a suite of Dansgaard-Oeschger Stadials between 120 and 40 ka before present (BP and thus seem to respond to abrupt northern hemispheric temperature changes. Between 65 and 40 ka BP, closures and openings of the Bering Strait could have additionally influenced TOC and C/N variability. CaCO3 content tends to anti-correlate with TOC and C/N on both orbital and millennial time scales, which we interpret as enhanced sediment advection from the carbonate-rich Canadian Arctic via an extended Beaufort Gyre during warm periods of the last two glacial-interglacial cycles and increased terrestrial organic carbon

  3. Main Controlling Factors on Hydrocarbon Accumulation and Distribution in Marine Sedimentary Sequences in South China

    Institute of Scientific and Technical Information of China (English)

    Cai Liguo; Zhou Yan; Bai Zhenrui


    Multiple source rock assemblages were deposited in the sedimentary provinces in South China in geologic history,and some of them were destructed by and some survived against multiple tectonic movements.Therefore,multiple sources,mixed sources,and uneven distribution of sources occurred in the marine sedimentary basins in South China during the late stage of hydrocarbon pooling.Epidiagenesis of the marine carbonate reservoirs and its modification to reservoir poroperm characteristics determined the formation and the scale of natural gas pools.The exploration practices show that the large to medium gas fields mainly occur in areas with high-quality reservoirs.Detailed study of the paleo-oil accumulations and typical oil and gas reservoirs reveals that the basins experienced multiphase superimposition and modification,leading to the distribution of the Paleozoic paleo-oil accumulations and bitumen in the peripheral areas.The phenomenon that oil and gas production concentrates in the Sichuan basin indicates that the overall sealing conditions of a basin determine the oil/gas potentials and the scale of oil and gas production.This is a critical factor controlling the accumulation and distribution of gas in the marine sequences in South China.The early oil and gas pools in the Yangtze platform left billions of bitumen in the peripheral areas due to the destruction of seals.Since the Himalayan,"late-generation and late-accumulation" gas pools represented by the gas pools in the Sichuan (四川) basin were formed in the marine sedimentary sequences in South China as a result of the change of the sealing conditions.Current gas discoveries appear to be "paleo-generation and paleo-accumulation" gas pools but actually are "late-generation and late-accumulation" gas pools.These patterns of hydrocarbon pooling clearly depict themselves in western Sichuan basin and Weiyuan (威远)gas field.It is revealed that the gas pools in the Sichuan basin were mainly formed as a result of

  4. Sedimentary and mineral dust sources of dissolved iron to the World Ocean

    Directory of Open Access Journals (Sweden)

    J. K. Moore


    Full Text Available A worldwide database of dissolved iron observations is used to improve simulations of the marine iron cycle within a global-scale, Biogeochemical Elemental Cycling (BEC ocean model. Modifications to the model include: 1 an improved particle scavenging parameterization based on the sinking mass flux of particulate organic material, biogenic silica, calcium carbonate, and mineral dust particles; 2 desorption of dissolved iron from sinking particles; and 3 an improved sedimentary source for dissolved iron. Most scavenged iron (90% is put on sinking particles to remineralize deeper in the water column. The model-observation mismatches are greatly reduced both in surface waters and in the deeper ocean. Inclusion of desorption has little effect on surface water iron concentrations where adsorption/scavenging is strongly dominant, but significantly increases simulated iron concentrations in the deep ocean. Our results suggest that there must be substantial removal of dissolved iron from subsurface waters (where iron concentrations are <0.6 nM in most regions to match observed distributions. Aggregation and removal on sinking particles of Fe bound to organic colloids is a likely mechanism.

    The improved BEC model is used to address the relative contributions of mineral dust and marine sediments in driving ocean productivity and observed dissolved iron distributions. The sedimentary iron source from the continental margins has a strong impact on open ocean iron concentrations, particularly in the North Pacific. Plumes of elevated dissolved iron concentrations develop at depth in the Southern Ocean, extending from source regions in the SW Atlantic and around New Zealand. The lower particle flux and weaker scavenging in this region allows the continental iron source to be advected far from source areas. Both the margin sediment and mineral dust Fe sources significantly impact global scale primary production, export production, and nitrogen fixation

  5. Studying the NE Eridania sedimentary sequence through the Mars 2020 rover (United States)

    Pajola, M.; Carter, J.; Rossato, S.; Baratti, E.; Mangili, C.; Coradini, M.; McBride, K. S.


    The landing sites we are proposing for the next Mars 2020 rover span between 28°29'30"S-28°53'0"S Latitude and 178°56'30"W°178°28'0"W Longitude, i.e. on the NE floor of a 1.1×106 km2 closed drainage basin [1]. This area, see Fig. 1, belongs to the bigger (3×106 km2) Eridania basin that gave birth to the Ma'adim Vallis through catastrophic overflow, and presenting a water table between 950 and 1250 m [1,2,3]. The crater counting chronology for this area gives an age between Early to Middle Noachian [4]. By means of OMEGA [5] and CRISM [6] data, a large clay-bearing sedimentary unit has been identified over almost the entire margin of the Eridania basin [7]. On our specific site, i.e. the NE margin of the Eridania basin, sequences of aqueous minerals are observed. Such sedimentary minerals are accessible through erosional windows into the first several tens of meters of the sedimentary sequence. The top-down mineral sequence identified on the landing sites area presents an unaltered capping unit that is overlying an Al-rich clay stratum (see Fig. 2) akin to Al-smectite and/or kaolins with a 3.8 Ga) during which liquid water was durably stable at the surface. The most valuable candidates for ancient Martian microbial life sustainability and preservation are longlasting environments, characterized by the presence of ponding water [10,11,12]: hence, the proposed site presents a high exobiological potential that is just waiting to be unveiled. Besides that, when putting into context the future results on Eridania Basin, i.e. the Ma'adim Vallis source, together with those obtained from the Spirit rover inside Gusev Crater (see Fig. 1), i.e. the Ma'adim Vallis mouth, a wide understanding of this intriguing canyon and of the Mars megaflooding age is foreseen. Besides the above scientific analysis showing than the NE side of the Eridania region fulfills entirely the Mars 2020 scientific requirements [13], the location of the proposed landing sites widely meets all the

  6. Heterogeneous arsenic enrichment in meta-sedimentary rocks in central Maine, United States

    Energy Technology Data Exchange (ETDEWEB)

    O' Shea, Beth, E-mail: [Department of Marine Science and Environmental Studies, University of San Diego, 5998 Alcala Park, San Diego, CA 92110 (United States); Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964 (United States); Stransky, Megan; Leitheiser, Sara [Department of Marine Science and Environmental Studies, University of San Diego, 5998 Alcala Park, San Diego, CA 92110 (United States); Brock, Patrick [School of Earth and Environmental Sciences, Queens College, City University of New York, 65-30 Kissena Blvd., Flushing, NY 11367 (United States); Marvinney, Robert G. [Maine Geological Survey, 93 State House Station, Augusta, ME 04333 (United States); Zheng, Yan [School of Earth and Environmental Sciences, Queens College, City University of New York, 65-30 Kissena Blvd., Flushing, NY 11367 (United States); Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964 (United States)


    Arsenic is enriched up to 28 times the average crustal abundance of 4.8 mg kg{sup −1} for meta-sedimentary rocks of two adjacent formations in central Maine, USA where groundwater in the bedrock aquifer frequently contains elevated As levels. The Waterville Formation contains higher arsenic concentrations (mean As 32.9 mg kg{sup −1}, median 12.1 mg kg{sup −1}, n = 38) than the neighboring Vassalboro Group (mean As 19.1 mg kg{sup −1}, median 6.0 mg kg{sup −1}, n = 38). The Waterville Formation is a pelitic meta-sedimentary unit with abundant pyrite either visible or observed by scanning electron microprobe. Concentrations of As and S are strongly correlated (r = 0.88, p < 0.05) in the low grade phyllite rocks, and arsenic is detected up to 1944 mg kg{sup −1} in pyrite measured by electron microprobe. In contrast, statistically significant (p < 0.05) correlations between concentrations of As and S are absent in the calcareous meta-sediments of the Vassalboro Group, consistent with the absence of arsenic-rich pyrite in the protolith. Metamorphism converts the arsenic-rich pyrite to arsenic-poor pyrrhotite (mean As 1 mg kg{sup −1}, n = 15) during de-sulfidation reactions: the resulting metamorphic rocks contain arsenic but little or no sulfur indicating that the arsenic is now in new mineral hosts. Secondary weathering products such as iron oxides may host As, yet the geochemical methods employed (oxidative and reductive leaching) do not conclusively indicate that arsenic is associated only with these. Instead, silicate minerals such as biotite and garnet are present in metamorphic zones where arsenic is enriched (up to 130.8 mg kg{sup −1} As) where S is 0%. Redistribution of already variable As in the protolith during metamorphism and contemporary water–rock interaction in the aquifers, all combine to contribute to a spatially heterogeneous groundwater arsenic distribution in bedrock aquifers. - Highlights: • Arsenic is enriched up to 138 mg kg

  7. Sedimentary record of Warta river floods in summer 2010 and winter 2011 nearby Poznan, W Poland (United States)

    Skolasińska, Katarzyna; Szczuciński, Witold; Mitręga, Marta; Rotnicka, Joanna; Jagodziński, Robert; Lorenc, Stanisław


    The Warta River valley nearby Poznań (W Poland) represents a meandering lowland river changed during the last 150 years by hydro-engineering works. Floods represent a major natural hazard in the region. However, historical records are not complete - particularly for former rural areas. Thus, sedimentary record may potentially offer additional insights into the flooding history. The big floods in the summer 2010 (the largest during the last 31 years) and winter 2011 offered opportunity to study their sedimentary record. The particular purposes were to identify sedimentary characteristics of summer and winter floods, interpret various phases of particular floods in the record, and assess impact of early post-depositional changes of the flood deposits. The surveys were conducted in six areas just after the floods and were repeated after several months, one and two years. The deposits spatial extent, thickness, surface bedforms and sediment type were assessed in the field. Sediment samples were further investigated for grain size distribution, organic matter content, roundness and sand grains surface features (SEM). The sandy flood deposits mostly build natural levee, side bars (climbing ripple lamination and planar cross laminations (only in crevasse splays). Vertical grain size changes in levee deposits revealed pensymmetric and/or reverse grading interpreted as effect of changing velocity during the rising water level. The sand grains were similar to the river channel sands and dominated by polished and sub-rounded quartz grains with preserved dissolution and dulled surface microfeatures. Further from the channel bank (few to few hundreds of meters) only discontinuous up to few mm thick organic rich mud layer was left, which after the summer flood was covered by algal mats. However the mud and mats were quickly reworked by new vegetation. The follow up surveys revealed that the preservation potential of flood deposits is low to moderate (only for sandy deposits

  8. Sedimentary and structural controls on seismogenic slumping within mass transport deposits from the Dead Sea Basin (United States)

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


    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


    Directory of Open Access Journals (Sweden)

    V. P. Semakin


    Full Text Available In terms of tectonics, the Sea of Okhotsk (Fig.1 is the epi-Mesozoic Okhotsk plate comprising the heterogeneous basement that is mainly pre-Cenozoic (the lower structural stage and the sedimentary cover that is mainly represented by the Paleogenic-Neogenic-Quaternary deposits with the Upper Cretaceous sedimentary rocks observed locally without a visible hiatus (the upper structural stage.Results of tectonic zoning of the sedimentary cover based on  lithophysical indicators (Fig. 2 are represented in the format of maps showing lithophysical complexes (LC within the limits of four regional seismo-stratigraphic complexes/structural layers (RSSC I-IV corresponding to the following time intervals: the pre-Oligocene К2-P1-2 (RSSC I, the Oligocene – Lower Miocene P3-N11 (RSSC II, the Lower-Mid Miocene N11-2 (RSSC III, and the Upper Miocene – Pliocene N13-N2 (RSSC IV. Diverse lithological-facies associations composing the RSSCs are grouped into the following lithophysical complexes (LC: 1 - coal-bearing silty-clayey-sandy terrigenous, 2 - sandy-silty-clayey terrigenous, 3 - silty-clayey-siliceous, and 4 - sandy-silty-clayey volcanic [Sergeyev, 2006].Tectonic zoning of the sedimentary cover based on structural indicators is carried out with reference to the sediment-thickness map [Sergeyev, 2006], including a significantly revised segment showing the area of the Deryugin basin [Semakin, Kochergin, 2013]. Results of such zoning are represented in the format of a structural-tectonic map (Fig. 3 showing orientations and morphology of the structural elements of the sedimentary cover, the thickness of the sedimentary cover, and amplitudes of relative uplifts and troughs.With reference to the structural-tectonic map (see Fig 3, the structural elements of different orders are grouped by their sizes, spatial positions and orientations and thus comprise tectonic sistems (Fig. 4, structural zones (Fig. 5 that unclude relative uplifts and troughs that are

  10. Summation of Divergent Power Series by Means of Factorial Series

    CERN Document Server

    Weniger, Ernst Joachim


    Factorial series played a major role in Stirling's classic book "Methodus Differentialis" (1730), but now only a few specialists still use them. This article wants to show that this neglect is unjustified, and that factorial series are useful numerical tools for the summation of divergent (inverse) power series. This is documented by summing the divergent asymptotic expansion for the exponential integral $E_{1} (z)$ and the factorially divergent Rayleigh-Schr\\"{o}dinger perturbation expansion for the quartic anharmonic oscillator. Stirling numbers play a key role since they occur as coefficients in expansions of an inverse power in terms of inverse Pochhammer symbols and vice versa. It is shown that the relationships involving Stirling numbers are special cases of more general orthogonal and triangular transformations.

  11. Product Summability Transform of Conjugate Series of Fourier Series

    Directory of Open Access Journals (Sweden)

    Vishnu Narayan Mishra


    Full Text Available A known theorem, Nigam (2010 dealing with the degree of approximation of conjugate of a signal belonging to Lipξ(t-class by (E,1(C,1 product summability means of conjugate series of Fourier series has been generalized for the weighted W(Lr,ξ(t, (r≥1,(t>0-class, where ξ(t is nonnegative and increasing function of t, by En1Cn1~ which is in more general form of Theorem 2 of Nigam and Sharma (2011.

  12. The influence of facies heterogeneity on the doublet performance in low-enthalpy geothermal sedimentary reservoirs

    DEFF Research Database (Denmark)

    Crooijmans, R. A.; Willems, C. J L; Nick, Hamid


    A three-dimensional model is used to study the influence of facies heterogeneity on energy production under different operational conditions of low-enthalpy geothermal doublet systems. Process-based facies modelling is utilised for the Nieuwerkerk sedimentary formation in the West Netherlands Basin...... and the energy recovery rate for different discharge rates and the production temperature (Tmin) above which the doublet is working. With respect to the results, we propose a design model to estimate the life time and energy recovery rate of the geothermal doublet. The life time is estimated as a function of N....../G, Tmin and discharge rate, while the design model for the energy recovery rate is only a function of N/G and Tmin. Both life time and recovery show a positive relation with an increasing N/G. Further our results suggest that neglecting details of process-based facies modelling may lead to significant...

  13. Velocity field measurements in sedimentary rock cores by magnetization prepared 3D SPRITE. (United States)

    Romanenko, Konstantin; Xiao, Dan; Balcom, Bruce J


    A time-efficient MRI method suitable for quantitative mapping of 3-D velocity fields in sedimentary rock cores, and granular samples is discussed. The method combines the 13-interval Alternating-Pulsed-Gradient Stimulated-Echo (APGSTE) scheme and three-dimensional Single Point Ramped Imaging with T(1) Enhancement (SPRITE). Collecting a few samples near the q-space origin and employing restricted k-space sampling dramatically improves the performance of the imaging method. The APGSTE-SPRITE method is illustrated through mapping of 3-D velocity field in a macroscopic bead pack and heterogeneous sandstone and limestone core plugs. The observed flow patterns are consistent with a general trend for permeability to increase with the porosity. Domains of low permeability obstruct the flow within the core volume. Water tends to flow along macroscopic zones of higher porosity and across zones of lower porosity.

  14. Nature and Architecture of the Sedimentary Deposits in the Trench of the Ecuadorian Subduction Margin (United States)

    Gonzalez, Miguel; Proust, Jean-Noel; Michaud, Francois; Pouderoux, Hugo; Ratzov, Gueorgui


    The active margin of Ecuador is characterized by strong tectonic erosion that contributes to the formation of a deep trench filled by a complex suite of sedimentary facies. Gravity flow sedimentation is ubiquitous along the margin and facies range from laterally continuous m-thick mass transport deposits to isolated cm-thick turbidites intercalated with hemipelagite and ash layers. However, the nature and architecture of those deposits remain equivocal. This study presents the interpretation of detailed bathymetry, high-resolution seismic profiles and sediment cores recently acquired along the 600 km-long Ecuadorian margin (ATACAMES campaign onboard the R/V L'Atalante, 2012). The margin comprises three morphological segments: (1) the central segment marked by the subduction of the Carnegie Ridge, which induced a narrow (10-30 km wide) and relatively shallow trench (3100-3700 m deep), a steep and gullied continental slope with no canyon and a 20-60 km wide shelf characterized by active subsidence, (2) the northern segment characterized by a wider (~100 km) and deeper (3800-4000 m) trench, a gentler gullied continental slope and similar shelf settings (10-50 km wide), (3) the southern segment presents a wide (20-60 km) and deep (4000-4700 m) trench, a starved continental slope with well-defined canyon systems and a wide subsiding shelf (50-100 km wide). The sedimentary dynamics along the margin is evaluated by the analysis of 15 sediment cores. High-resolution visual description of the cores, X-Ray imagery and the measurement of petrophysical properties (gamma density, magnetic susceptibility, P-wave velocity) led to the identification of 6 sedimentary facies that characterize 6 sedimentary processes: Turbidite beds (turbidity currents), Hemipelagites (continuous marine sedimentation), Tephras (airfall ash layers consecutive to volcanic eruptions), Debris flow deposits (cohesive debris flows), Megaturbidite/Homogenite (large-scale and/or hybrid gravity flows), Mass

  15. Archaeology. Sedimentary DNA from a submerged site reveals wheat in the British Isles 8000 years ago. (United States)

    Smith, Oliver; Momber, Garry; Bates, Richard; Garwood, Paul; Fitch, Simon; Pallen, Mark; Gaffney, Vincent; Allaby, Robin G


    The Mesolithic-to-Neolithic transition marked the time when a hunter-gatherer economy gave way to agriculture, coinciding with rising sea levels. Bouldnor Cliff, is a submarine archaeological site off the Isle of Wight in the United Kingdom that has a well-preserved Mesolithic paleosol dated to 8000 years before the present. We analyzed a core obtained from sealed sediments, combining evidence from microgeomorphology and microfossils with sedimentary ancient DNA (sedaDNA) analyses to reconstruct floral and faunal changes during the occupation of this site, before it was submerged. In agreement with palynological analyses, the sedaDNA sequences suggest a mixed habitat of oak forest and herbaceous plants. However, they also provide evidence of wheat 2000 years earlier than mainland Britain and 400 years earlier than proximate European sites. These results suggest that sophisticated social networks linked the Neolithic front in southern Europe to the Mesolithic peoples of northern Europe.

  16. Sedimentary and mineral dust sources of dissolved iron to the world ocean

    Directory of Open Access Journals (Sweden)

    J. K. Moore


    from sinking particles; and 3 an improved sedimentary source for dissolved iron. Most scavenged iron (90% is put on sinking particles to remineralize deeper in the water column. The model-observation differences are reduced with these modifications. The improved BEC model is used to examine the relative contributions of mineral dust and marine sediments in driving dissolved-iron distributions and marine biogeochemistry. Mineral dust and sedimentary sources of iron contribute roughly equally, on average, to dissolved iron concentrations. The sedimentary source from the continental margins has a strong impact on open-ocean iron concentrations, particularly in the North Pacific. Plumes of elevated dissolved-iron concentrations develop at depth in the Southern Ocean, extending from source regions in the SW Atlantic and around New Zealand. The lower particle flux and weaker scavenging in the Southern Ocean allows the continental iron source to be advected far from sources. Both the margin sediment and mineral dust Fe sources substantially influence global-scale primary production, export production, and nitrogen fixation, with a stronger role for the dust source. Ocean biogeochemical models that do not include the sedimentary source for dissolved iron, will overestimate the impact of dust deposition variations on the marine carbon cycle. Available iron observations place some strong constraints on ocean biogeochemical models. Model results should be evaluated against both surface and subsurface Fe observations in the waters that supply dissolved iron to the euphotic zone.

  17. Radiogenic heat production in sedimentary rocks of the Gulf of Mexico Basin, south Texas (United States)

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


    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

  18. Glacial atmospheric CO2 decline in association with decrease of marine sedimentary phosphorus

    Institute of Scientific and Technical Information of China (English)

    WENG; Huanxin; ZHANG; Xingmao; WU; Nengyou; WANG; Ying; CHEN; Lihong; ZHONG; Hexian; QIN; Yachao


    The environmental and biogeochemical information extracted from the sediments collected from the northern shelf of the South China Sea shows that terrigenous inputs of phosphorus into the sea remained relatively constant, and the variation of phosphorus contents at different depths was caused by climatic and environmental changes. The findings also suggest that the vertical variation of phosphorus content was opposite to those of calcium carbonate and cadmium, and the functional correlation between CO2 and PO43? in seawater was given by calculating the chemical equilibrium, indicating that the accumulation of marine sedimentary phosphorus may have something to do with the variation of atmospheric CO2. The decreased phosphorus accumulation as well as the correspondingly-increased calcium carbonate content might be one of key factors causing glacial atmospheric CO2 decline.

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

    Energy Technology Data Exchange (ETDEWEB)

    Francisco, N.F.; Azambuja, N.C.; Mello, M.R. (Petrobras, Rio de Janeiro (Brazil))


    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. Triassic rift-related sedimentary basins in northern Chile (24° 29°S) (United States)

    Suarez, M.; Bell, C. M.


    Triassic rocks in northern Chile (latitude 24°-29°S) include marine and continental rift-related sedimentary deposits, associated with basaltic, andesitic, and silicic volcanic rocks. Five main successions include the deposits of two marine basins (Profeta and San Félix) separated by three continental basins (Cifuncho, La Ternera, and La Coipa). The marine strata include turbidites and debris flow deposits interpreted as coarse-grained fan-delta sediments. The continental sediments include lacustrine fan delta, open lake, braided river, alluvial fan, and sabkha deposits. The widespread fan-delta systems (both marine and lacustrine), together with abrupt lateral and vertical facies discontinuities and large-scale depositional cycles, are indicative of rift-controlled sedimentation. The associated magmatic activity indicates that this rifting was the product of subduction-related extension or strike-slip movement on the active plate margin. Triassic rifting was followed in Late Triassic to Early Jurassic times by widespread thermotectonic subsidence.

  1. Hydroxyl radicals form in natural sediments - effects on sedimentary organic matter (United States)

    Skoog, Annelie; Alejandro Arias-Esquivel, Victor


    We show that hydroxyl radicals form at the oxic anoxic interface in marine sediments from ferrous iron reacting with hydrogen peroxide in the Fenton reaction. The aggressive nature of hydroxyl radicals makes it likely that they participate in degradation of sedimentary organic matter (SOM). We used terephthalic acid (TPA) to trap the hydroxyl radicals in sediment cores - TPA reacts with hydroxyl radicals to form the highly fluorescent product TPAOH. Results indicated formation of TPAOH at high concentrations at the oxic-anoxic interface. We also subjected SOM to hydroxyl radicals formed by the Fenton reaction, which resulted in changes in fluorescence properties and chemical composition. This is the first study showing formation of hydroxyl radicals and their effect on SOM, which is a previously unknown mechanism in the global carbon cycle.

  2. The Holocene sedimentary history of the Kangerlussuaq Fjord-valley fill, West Greenland

    DEFF Research Database (Denmark)

    Storms, Joep E.A.; de Winter, Ilja L.; Overeem, Irina


    from a temporary stabilization phase of the GIS and prograded rapidly over the glaciomarine deposits of Phase I. Further inland, proglacial lake formation and subsequent sedimentary infill associated with the ongoing GIS retreat is represents the second depocenter. The Watson River connected both...... depocenters by a flood plain which transferred sediment from the GIS to the Keglen delta. Ongoing sea level fall due to glacio-isostastic uplift combined with a gradually cooler and dryer climate resulted in terrace formation along the Watson River flood plain. Around 4000 yr BP, the GIS margin reached its...... most landward location and began to advance to its present location. The final phase (Phase III; Watson River. Simultaneously, subaqueous channels...

  3. Palaeomagnetism, petrology and geochronology of tertiary magmatic and sedimentary units from Iran (United States)

    Bina, Mohamad Mansour; Bucur, Ileana; Prevot, Michel; Meyerfeld, Yves; Daly, Lucien; Cantagrel, Jean Marie; Mergoil, Jean


    An amount of 160 samples from igneous and sedimentary formations of Palaeocene or Eocene age was collected in Iran, northeast of the Zagros belt. Palaeomagnetic analyses, petrological studies, and K-Ar dating indicate Palaeocene and Eocene palaeomagnetic directions in the Zabol-Baluch region (East Iranian Range) and show that the area remained approximately stable with respect to the Eurasian and African plates from the beginning of the Cainozoic Era. Conversely, large post-Eocene deformations occurred in Central Iran. These large rotations are both clockwise and anti-clockwise. They might have resulted from lateral shears between Arabia and northeast Iran. The Central Elburz underwent a large clockwise rotation which is probably late Oligocene in age. As a whole, our results show that the so-called "Persian Plate" did not exist during the Cainozoic Era.

  4. Experiments in a Deep Underground Science and Engineering Laboratory (DUSEL) Hosted in Sedimentary Rocks (United States)

    Burbey, T. J.; Kimballton, M. O.; Science Team


    Sedimentary-rock environments, particularly those dominated by carbonate rock, provide unique opportunities for geoscientists, geobiologists, and geophysicists, to perform revolutionary experiments aimed at answering fundamental science questions and satisfying our societal demands for resources and environmental stewardship. As part of the National Science Foundation's DUSEL initiative, the selected site should offer structurally and biologically diverse environments. At the same time, the site should offer host rock capable of providing safely engineered hallways and laboratories at depths as great as 2,200 m for numerous deep underground physics, engineering, and earth science experiments. An ideal sedimentary-rock environment offers the prospect of highly folded, thrusted, and fractured rocks that allow opportunities to study the 3-D behavior of thrusts that propagate parallel to bedding as well as those that ramp across bedding. Flow dynamics along and across deeply buried faults is poorly understood. Experiments will be developed at various scales to assess flow and transport processes to better quantify hydrogeological mechanisms influencing flow and possible aquifer compartmentalization. Seismic reflection images, vertical seismic profiles, and tomograms will provide details of the fault properties and geometry, which can be verified in-situ. Repeated overthrusted sequences provide opportunities for geobiologists to investigate how microbes in rocks of similar age are affected by differences in pressure, temperature, and depth. Carbonate rocks provide opportunities to study energy sources and adaptations for nutrient acquisition, reproduction, stability, survival, and repair under extreme conditions. Results from these investigations will permit comparisons with other foreland fold-thrust belts worldwide. Fossil fuels remain the world's main energy resource and the large majority of these are hosted in sedimentary rocks. Improved methods for reservoir

  5. How to find the sedimentary archive of fluvial pollution in a bedrock-confined river reach (United States)

    Elznicova, Jitka; Matys Grygar, Tomas; Kiss, Timea; Lelkova, Tereza; Balogh, Marton; Sikora, Martin


    The Ohre River springs in the Eastern Germany and it is a tributary of the Labe (Elbe) River in Northwest Bohemia. The river received pollution from several sources during the last five centuries. Most of the pollution sources located along the upper and middle reaches, where the depositional and erosional pattern of the river is highly variable. The upper part of the catchment consists of mainly felsic rocks and the river has a broad floodplain. The middle reach and its right-bank tributaries are deeply incised into the Doupovske Hory Mts., which consists of mafic volcanic rocks; whereas the left-bank tributaries are incised into intrusive and metamorphic rocks of the Krusne Hory Mts. (Ore mountains) with several local ore mines (Ag, Pb and U) in particular in around Olovi and Jachymov. Due to the geologic and geomorphologic complexity, deposition of historical sediments in the middle reach has been spatially limited and uneven, and anomalous background concentrations of risk elements are expected. As a consequence, in the middle reach of the Ohre River it is difficult to find a useful sedimentary archive of historical pollution, though it is desired for two main reasons: (1) to decipher the undocumented and poorly described pollution history from the Krusne Hory Mts. and (2) to better understand the retention of pollutants in the transport zones of a confined river system. Based on historical maps we identified a side-bar (35x320 m) in the middle reach of the river near Straz on Ohre and aimed to describe its formation, its recent erosion/deposition history and to evaluate its sedimentary archive value. In the first half of the 19th century it was an island separated from the valley edge by a side channel. Since then there has been no apparent lateral accretion of the bar (its shape has not been changed), but the upstream part of the side channel aggraded by a sediment plug. We evaluated the current bar topography and geomorphology by a detailed field survey

  6. Submarine sedimentary features on a fjord delta front, Queen Inlet, Glacier Bay, Alaska (United States)

    Carlson, Paul R.; Powell, Ross D.; Phillips, Andrew C.


    Side-scan sonar images provide a view of an actively changing delta front in a marine outwash fjord in Glacier Bay, Alaska. Numerous interconnected gullies and chute-like small channels form paths for the transport of sand and coarse silt from the braided glacial outwash streams on the delta plain to the sinuous turbidity-current channels incised into the fjord floor. These turbidity-current channels carry coarse sediment through the fjord and into the adjoining glacial trunk valley. Several sedimentary processes affect the development of this delta front: overflow plumes deposit fine sediment; sediment gravity flows result from episodic delivery of large loads of coarse sediment; and mass movement may be triggered by earthquakes and, more regularly, by spring-tidal drawdown or hydraulic loading.

  7. Correlation between logging records and superficial series of the Continental Aptiense-Albiense of the extreme SW of the Basco-Cantabrian basin and their application in the identification of lignitiferous zones. Correlacion entre registros de sondeos y series de superficie del Aptiense-Albiense continental del extremo SW de la Cuenca Vascocantabrica y su aplicacion a la identificacion de zonas lignitiferas

    Energy Technology Data Exchange (ETDEWEB)

    Arnaiz, I.; Robles, S.; Pujalte, V. (Univ. del Pais Vasco, Bilbao (Spain). Dept. Estratigrafia, Geodinamica y Paleontologia)


    The materials from Miocene age which appeared in this area are attributed to the so-called 'post-manto' materials. Those materials form a calcareous series with more detritical parts generated in the zone between the continent and the shallow platform. Sub-environments are very well represented in a sequence which includes four tecto-sedimentary unities. 6 refs., 3 figs.

  8. Sedimentary environment influences the effect of an infaunal suspension feeding bivalve on estuarine ecosystem function.

    Directory of Open Access Journals (Sweden)

    Hannah F E Jones

    Full Text Available The suspension feeding bivalve Austrovenus stutchburyi is a key species on intertidal sandflats in New Zealand, affecting the appearance and functioning of these systems, but is susceptible to several environmental stressors including sedimentation. Previous studies into the effect of this species on ecosystem function have been restricted in space and time, limiting our ability to infer the effect of habitat change on functioning. We examined the effect of Austrovenus on benthic primary production and nutrient dynamics at two sites, one sandy, the other composed of muddy-sand to determine whether sedimentary environment alters this key species' role. At each site we established large (16 m(2 plots of two types, Austrovenus addition and removal. In winter and summer we deployed light and dark benthic chambers to quantify oxygen and nutrient fluxes and measured sediment denitrification enzyme activity to assess denitrification potential. Rates of gross primary production (GPP and ammonium uptake were significantly increased when Austrovenus was added, relative to removed, at the sandy site (GPP, 1.5 times greater in winter and summer; ammonium uptake, 8 times greater in summer; 3-factor analysis of variance (ANOVA, p<0.05. Denitrification potential was also elevated in Austrovenus addition plots at the sandy site in summer (by 1.6 times, p<0.1. In contrast, there was no effect of Austrovenus treatment on any of these variables at the muddy-sand site, and overall rates tended to be lower at the muddy-sand site, relative to the sandy site (e.g. GPP was 2.1 to 3.4 times lower in winter and summer, respectively, p<0.001. Our results suggest that the positive effects of Austrovenus on system productivity and denitrification potential is limited at a muddy-sand site compared to a sandy site, and reveal the importance of considering sedimentary environment when examining the effect of key species on ecosystem function.

  9. A synthesis of sedimentary records of Australian environmental change during the last 2000 years (United States)

    Tyler, J. J.; Karoly, D. J.; Gell, P.; Goodwin, I. D.


    Our understanding of Southern Hemispheric climate variability on multidecadal to multicentennial timescales is limited by a scarcity of quantitative, highly resolved climate records, a problem which is particularly manifest in Australia. To date there are no quantitative, annually resolved records from within continental Australia which extend further back in time than the most recent c. 300 years [Neukom and Gergis, 2012; PAGES 2k Consortium, 2013]. By contrast, a number of marine, lake, peat and speleothem sedimentary records exist, some of which span multiple millennia at sub-decadal resolution. Here we report a database of existing sedimentary records of environmental change in Australia [Freeman et al., 2011], of which 25 have sample resolutions 500 years in duration. The majority of these records are located in southeastern Australia, providing an invaluable resource with which to examine regional scale climate and environmental change. Although most of the records can not be quantitatively related to climate variability, Empirical Orthogonal Functions coupled with Monte Carlo iterative age modelling, demonstrate coherent patterns of environmental and ecological change. This coherency, as well as comparisons with a limited number of quantitative records, suggests that regional hydroclimatic changes were responsible for the observed patterns. Here, we discuss the implications of these findings with respect to Southern Hemisphere climate during the last 2000 years. In addition, we review the progress and potential of ongoing research in the region. References: Freeman, R., I. D. Goodwin, and T. Donovan (2011), Paleoclimate data synthesis and data base for the reconstruction of climate variability and impacts in NSW over the past 2000 years., Climate Futures Technical Report, 1/2011, 50 pages. Neukom, R., and J. Gergis (2012), Southern Hemisphere high-resolution palaeoclimate records of the last 2000 years, Holocene, 22(5), 501-524, doi:10

  10. Dolomitization and sedimentary cyclicity of the Ordovician, Silurian, and Devonian rocks in South Estonia

    Directory of Open Access Journals (Sweden)

    Kallaste, Toivo


    Full Text Available The distribution and composition of dolomitized rocks and stoichiometry of dolomite in southern Estonia in the Ordovician, Silurian, and Devonian were studied on the background of the facies, sedimentary cyclicity (nine shallowing-up cycles, and evolution of the palaeobasins. The composition of rocks and lattice parameters of dolomite were investigated using the X-ray diffraction, X-ray fluorescence, titration and gravimetric analyses, and porosity measurements. The formation of dolostones is directly determined by the cyclic evolution of palaeobasins. Dolomitized rocks belong to the shallow-water inner shelf or tidal/lagoonal facies belt of regressive phases of sedimentary cycles. Sediments of the deep shelf/transitional environment and transgressive phases are not dolomitized. The most stoichiometric is secondary replacive dolomite of Silurian and upper Ordovician dolostones, formed during the early diagenesis of normal-marine (saline shallow-shelf calcitic sediments. The content of insoluble residue does not affect the stoichiometry. The changes in lattice parameters are induced by the Ca/Mg ratio in the dolomite lattice. The dolomite of the dolostones contacting limestone or containing calcite has an expanded lattice. The primary (syngenetic dolostone of the lagoonal or tidal flat belt has also an expanded lattice. No dolomitizing effect of the waters of the Devonian palaeobasin on the underlying rocks was revealed. The whole data set of the studied dolostones is consistent with the marine water environment in the palaeobasin at the corresponding time and shows no sign of the inflow of external fluids. It suggests that the microbial model of dolomite formation may characterize the Ordovician, Silurian, and Devonian in southern Estonia. The occurrence of dolostones between undolomitized rocks limits the time of dolomitization to the early diagenetic stage.

  11. Heterogeneous arsenic enrichment in meta-sedimentary rocks in central Maine, United States (United States)

    O’Shea, Beth; Stransky, Megan; Leitheiser, Sara; Brock, Patrick; Marvinney, Robert G.; Zheng, Yan


    Arsenic is enriched up to 28 times the average crustal abundance of 4.8 mg kg−1 for meta-sedimentary rocks of two adjacent formations in central Maine, USA where groundwater in the bedrock aquifer frequently contains elevated As levels. The Waterville Formation contains higher arsenic concentrations (mean As 32.9 mg kg−1, median 12.1 mg kg−1, n=36) than the neighboring Vassalboro Group (mean As 19.1 mg kg−1, median 6.0 mg kg−1, n=36). The Waterville Formation is a pelitic meta-sedimentary unit with abundant pyrite either visible or observed by scanning electron microprobe. Concentrations of As and S are strongly correlated (r=0.88, p<0.05) in the low grade phyllite rocks, and arsenic is detected up to 1,944 mg kg−1 in pyrite measured by electron microprobe. In contrast, statistically significant (p<0.05) correlations between concentrations of As and S are absent in the calcareous meta-sediments of the Vassalboro Group, consistent with the absence of arsenic-rich pyrite in the protolith. Metamorphism converts the arsenic-rich pyrite to arsenic-poor pyrrhotite (mean As 1 mg kg−1, n=15) during de-sulfidation reactions: the resulting metamorphic rocks contain arsenic but little or no sulfur indicating that the arsenic is now in new mineral hosts. Secondary weathering products such as iron oxides may host As, yet the geochemical methods employed (oxidative and reductive leaching) do not conclusively indicate that arsenic is associated only with these. Instead, silicate minerals such as biotite and garnet are present in metamorphic zones where arsenic is enriched (up to 130.8 mg kg−1 As) where S is 0%. Redistribution of already variable As in the protolith during metamorphism and contemporary water-rock interaction in the aquifers, all combine to contribute to a spatially heterogeneous groundwater arsenic distribution in bedrock aquifers. PMID:24861530

  12. Natural radionuclides in major aquifer systems of the Parana sedimentary basin, Brazil

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    Bonotto, Daniel Marcos, E-mail: [Departamento de Petrologia e Metalogenia, IGCE-Instituto de Geociencias e Ciencias Exatas, UNESP-Universidade Estadual Paulista Julio de Mesquita Filho, Av. 24-A, No. 1515 - CP 178, CEP 13506-900-Rio Claro, SP (Brazil)


    This paper describes the natural radioactivity of groundwater occurring in sedimentary (Bauru and Guarani) and fractured rock (Serra Geral) aquifer systems in the Parana sedimentary basin, South America that is extensively used for drinking purposes, among others. The measurements of gross alpha and gross beta radioactivity as well the activity concentration of the natural dissolved radionuclides {sup 40}K, {sup 238}U, {sup 234}U, {sup 226}Ra, {sup 222}Rn, {sup 210}Po and {sup 210}Pb were held in 80 tubular wells drilled in 21 municipalities located at Sao Paulo State and its border with Mato Grosso do Sul State in Brazil. Most of the gross alpha radioactivity data were below 1 mBq/L, whereas values exceeding the gross beta radioactivity detection limit of 30 mBq/L were found. The radioelement solubility in the studied systems varied according to the sequence radon>radium>other radionuclides and the higher porosity of sandstones relatively to basalts and diabases could justify the enhanced presence of dissolved radon in the porous aquifer. The implications of the data obtained in terms of standards established for defining the drinking water quality have also been discussed. The population-weighted average activity concentration for these radionuclides was compared to the guideline value of 0.1 mSv/yr for the total effective dose and discussed in terms of the choice of the dose conversion factors. - Highlights: > Integration of distinct radiometric data acquired in groundwaters. > Radiation dose in important hydrological resources in South America. > Contribution of {sup 226}Ra for the more accentuated radiation dose in aquifers. > Dose factors for Rn and generation of values exceeding the maximum of 0.1 mSv/yr.

  13. Sedimentary record of recent climate impacts on an insular coastal lagoon in the Gulf of California (United States)

    Cuellar-Martinez, Tomasa; Ruiz-Fernández, Ana Carolina; Sanchez-Cabeza, Joan-Albert; Alonso-Rodríguez, Rosalba


    Sedimentary records are useful to evaluate environmental changes, either from natural or anthropogenic causes, such as global and climate change. The recent changes in accumulation rates and geochemical characteristics (grain size distribution, elemental composition, organic carbon and carbonate concentrations) recorded in a sediment core from San Jose Island Lagoon (SJIL, Gulf of California) were evaluated to determine its relationship with anthropogenic impacts and climatic variability. The 210Pb-derived chronology was corroborated with 239+240Pu and 137Cs stratigraphic markers. The mass accumulation rate increased up to ∼3 times during the past ∼100 years (0.16 ± 0.03 to 0.51 ± 0.06 g cm-2 yr-1). The contents of terrigenous and marine (salinity) indicator elements, as well as fine-grained sediments, also increased considerably, although no anthropization evidences were observed; indeed, the enrichment factor of trace elements indicated that the ecosystem is still a pristine environment. By using multivariate statistical techniques, we inferred that the larger input of fine-grained terrigenous sediments could be related to the enhancement of soil erosion from the catchment, under the influence of higher rainfall rates, especially during the last 20 years. In addition, the higher concentrations of salinity indicator elements most likely resulted from higher evaporation rates in the lagoon, caused by higher minimum atmospheric temperatures. We concluded that recent climate variability has become the main driver for sedimentary geochemical changes in San Jose Island Lagoon. These observations confirmed the usefulness of 210Pb-dated geochemical sediment records to study the impacts of recent climate variability where long-term environmental data is scarce or non-existent.

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

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


    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 Upstream and Downstream impact of Milankovitch cycles in continental nonmarine sedimentary records (United States)

    Valero, Luis; Garcés, Miguel; Huerta, Pedro; Cabrera, Lluís


    Discerning the effects of climate in the stratigraphic record is crucial for the comprehension of past climate changes. The signature of climate in sedimentary sequences is often assessed by the identification of Milankovitch cycles, as they can be recognized due to their (quasi) periodic behaviour. The integration of diverse stratigraphic disciplines is required in order to understand the different processes involved in the expression of the orbital cycles in the sedimentary records. New advances in Stratigraphy disclose the different variables that affect the sedimentation along the sediment routing systems. These variables can be summarized as the relationship between accommodation and sediment supply (AS/SS), because they account for the shifts of the total mass balance of a basin. Based in these indicators we propose a synthetic model for the understanding of the expression of climate in continental basins. Sedimentation in internally drained lake basins is particularly sensitive to net precipitation/evaporation variations. Rapid base level oscillations modify the AS/SS ratio sufficiently as to mask possible sediment flux variations associated to the changing discharge. On the other hand, basins lacking a central lacustrine system do not experience climatically-driven accommodation changes, and thus are more sensitive to archive sediment pulses. Small basins lacking carbonate facies are the ideal candidates to archive the impact of orbital forcing in the landscapes, as their small-scale sediment transfer systems are unable to buffer the upstream signal. Sedimentation models that include the relationship between accommodation and sediment supply, the effects of density and type of vegetation, and its coupled response with climate are needed to enhance their reliability.

  16. Thin-skinned deformation of sedimentary rocks in Valles Marineris, Mars (United States)

    Metz, Joannah; Grotzinger, John; Okubo, Chris; Milliken, Ralph


    Deformation of sedimentary rocks is widespread within Valles Marineris, characterized by both plastic and brittle deformation identified in Candor, Melas, and Ius Chasmata. We identified four deformation styles using HiRISE and CTX images: kilometer-scale convolute folds, detached slabs, folded strata, and pull-apart structures. Convolute folds are detached rounded slabs of material with alternating dark- and light-toned strata and a fold wavelength of about 1 km. The detached slabs are isolated rounded blocks of material, but they exhibit only highly localized evidence of stratification. Folded strata are composed of continuously folded layers that are not detached. Pull-apart structures are composed of stratified rock that has broken off into small irregularly shaped pieces showing evidence of brittle deformation. Some areas exhibit multiple styles of deformation and grade from one type of deformation into another. The deformed rocks are observed over thousands of kilometers, are limited to discrete stratigraphic intervals, and occur over a wide range in elevations. All deformation styles appear to be of likely thin-skinned origin. CRISM reflectance spectra show that some of the deformed sediments contain a component of monohydrated and polyhydrated sulfates. Several mechanisms could be responsible for the deformation of sedimentary rocks in Valles Marineris, such as subaerial or subaqueous gravitational slumping or sliding and soft sediment deformation, where the latter could include impact-induced or seismically induced liquefaction. These mechanisms are evaluated based on their expected pattern, scale, and areal extent of deformation. Deformation produced from slow subaerial or subaqueous landsliding and liquefaction is consistent with the deformation observed in Valles Marineris.

  17. Uncertainty quantification of overpressure buildup through inverse modeling of compaction processes in sedimentary basins (United States)

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


    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.

  18. Sedimentary Basins in the Western White Nile, Sudan, as Indicated by a Gravity Survey

    Institute of Scientific and Technical Information of China (English)


    An academic geophysical research as a regional gravity survey was made during 1994 in the Western White Nile to infer the shallow crustal structures in the area. The result of the survey was compiled as a Bouguer anomaly map with a contour interval of 2 ×10-5m/s2. It is found that the negative residual anomalies are related to the Upper Cretaceous sediments (Nubian Sandstone Formation) filling all depressions in the Basement complex surface while the positive residual anomalies are attributed to the relatively shallow or outcropping Basement rocks and the steep gravity gradients are resulting from the sharp contacts between the sedimentary infill and the Basement rocks. To define the geological structures in the area, 9 profiles were studied. For each of the profiles, measured and computed Bouguer gravity anomalies, crustal density model, subsurface geology evaluation were performed. A G-model computer program was applied in the gravity modeling, which is based on the line-integral method of gravity computation. A geological/structural map was proposed showing inferred sedimentary basins, faulting troughs and uplifted Basement block and tectonic trends. The basins are believed to be fault-controlled which developed by extensional tectonics (pull-apart mechanism). As for the mechanism and cause of faulting, the area is considered as a part of the Central Sudan rift system which had been subjected to several tectonic events since Early Cambrian to Tertiary times which resulted in the formation of several fracture systems associated with block subsidence, rifting and basin formation.

  19. Uncertainty quantification of overpressure buildup through inverse modeling of compaction processes in sedimentary basins (United States)

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


    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.

  20. Discrete Element Models of the Micromechanics of Sedimentary Rock: The Role of Organization vs. Friction (United States)

    Boutt, D. F.; McPherson, B. J.


    The micromechanics of sedimentary rock deformation are a fundamental aspect of many research fields, ranging from geotechnical engineering to petroleum recovery and hazardous waste disposal. Laboratory triaxial tests yield information concerning macroscopic behaviors but are not capable of quantifying micromechanical processes such as microcracking and localization. Thus, to quantify micromechanical processes we employed the discrete element method (DEM) of rock deformation, calibrated with triaxial test results. This DEM simulates rock using rigid disc shaped particles bonded at contacts between particles. Previous studies demonstrated that this type of DEM can qualitatively and quantitatively mimic macroscopic behaviors of triaxial tests. An important conclusion of these studies is that a number of particles must be bonded together with higher bond strengths than the surrounding particles to achieve a steeper strength envelope of rocks. This process, termed clustering, is the focus of this study. We hypothesize that since clusters posses a more complicated geometry, they may increase failure strength at elevated confining pressures by interlocking and creating a higher apparent friction. An alternative hypothesis is that the clusters change force chain development by allowing chains to persist longer in specimens. This ultimately causes failure to occur at higher strengths compared to unclustered material. A systematic study comparing effects of cluster shape, particle friction, and force chain development was undertaken. Several model simulations with various cluster shapes and sizes were compared with each other as well as single particle models with high friction coefficients (>1). Preliminary results suggest that the organization of the particle clusters play a key role in increasing the strength envelope. Particle friction coefficients needed to increase slopes of the strength envelopes are well beyond those of geological materials measured in the laboratory

  1. Sedimentary Response of AN Ephemeral Lake during Deglacial and Holocene Climate Evolution, Swan Lake, Southeast Idaho. (United States)

    Rosario, J. J.; Miller, D. M.; Wahl, D.; Anderson, L.; Tripati, A.; Presnetsova, L.; Oviatt, C. G.; McGeehin, J. P.; Bright, J. E.


    Perennial water systems are important ecological resources in the arid western US and provide many ecosystem services. Lakes can record fluctuations in climate (such as temperature and effective moisture) and can offer insight into regional variations in climate patterns. We studied a 7.65-m core from Swan Lake, which is a small lake and wetland complex that seasonally overflows, to examine small scale climate changes in its continuous sedimentary record. Our core is similar to that studied by Bright (1966), which exhibits two primary sedimentary facies, mud and peat, with a time span of 13.5 cal ka. The methodology includes radiocarbon dating, particle size analyses, sediment mineralogy, stable isotopes and clumped isotopes on calcium carbonate. Mud in the lower half of the core is primarily composed of clay and silt-size quartz-feldspar, but it transitions to calcium carbonate mud. Clays change from 660 to 585 cm and 350 to 220 cm in the core with an increase in kaolinite and illite upward. Ostracods in the carbonate muds are fairly uniform, indicating a mixture of wetland and lake environments from the last 5.8 ka. Similarly, summer temperatures obtained using Δ47 measurements show fluctuations in the range of 18.1 to 23.4 oC with carbonate muds generally corresponding to lower temperatures and peats to higher temperatures. We interpret muds as open water, shallow lake conditions and peats as wetlands across the floor of the ephemeral lake. If our interpretations are correct, the time from onset of the Younger Dryas to the end of the early Holocene was effectively dry, with low groundwater discharge. Similar events occurred from 4.7 to 1.0 ka and briefly at ~400 cal yr BP. Warmer climate may lead to effective moisture increase in this part of the eastern Great Basin.

  2. Integrated Provenance Studies in Northwestern South America, Linking Tectonic and Sedimentary Processes (United States)

    Montes, C.; Cardona, A.; Ramirez, V. O.; Bayona, G.; Ayala, C.; Valencia, V.


    Post-collisional late Eocene to Oligocene extensional basins (Plato-San Jorge basin in Colombia) and syn-collisional basins to the east contain the record of drainages and source areas as a former passive margin obliquely collided with the Caribbean deformation front. A 2 to 8 km thick, shallowing-upward and almost entirely fine-grained, upper Eocene and younger sedimentary sequence contains the record of post-collisional paleogeography behind the advancing deformation front. Sedimentation in the syn-collisional margin is fragmentary along the northern margins of Colombia and Venezuela in the Guajira province. An integrated provenance approach is being undertaken with detrital zircon geochronology, whole rock geochemistry, heavy mineral analysis and tectonic modeling. Source areas contain distinctive assemblages that should be diagnostic and include cratonic contributions with Grenville and older provinces, Andean contributions with Mesozoic-age signatures and Caribbean contributions with latest Cretaceous and Paleogene contributions. The complex Paleogene tectonic interactions along the northwestern South American margin include the simultaneous opening of basins (Plato-San Jorge basin in Colombia), micro-block rotation (Santa Marta massif), shortening and mountain building (Perija range) and oblique accretionary wedges along the margin (Sinu-San Jacinto deformed belts). Rivers draining the interior of South America to the north would have been deflected by this Paleogene configuration, and local drainages would have similarly developed in response to changing depocenters. Distinctive signatures should have developed in the sedimentary sequence as the sources dynamically changed from cratonic (Grenville and older cratonic) to Andean (Mesozoic continental crust and reworked) to Caribbean (volcanic arcs and collision zones).

  3. Geophysical anatomy of counter-slope scarps in sedimentary flysch rocks (Outer Western Carpathians) (United States)

    Tábořík, P.; Lenart, J.; Blecha, V.; Vilhelm, J.; Turský, O.


    A multidisciplinary geophysical survey, consisting of electrical resistivity tomography (ERT), ground penetrating radar (GPR), shallow seismic refraction (SSR) and gravity survey (GS), was used to investigate the counter-slope scarps, one of the typical manifestations of the relaxed zones of rock massifs, and the possible initial stages of deep-seated landslides (DSLs). Two upper parts of the extensive DSLs within the Moravskoslezské Beskydy Mountains (Outer Western Carpathians - OWC) built by the sedimentary flysch rock were chosen as the testing sites. A combined geophysical survey on the flysch rocks was performed on both localities to enhance our present findings. The survey revealed that the ERT is able to reliably detect underground discontinuities, which are manifested at the ground surface by one of the typical landforms (tension cracks, trenches, pseudokarst sinkholes, double-crested ridges and counter-slope scarps). Previous studies suggested that bedrock discontinuities should be depicted by high-resistivity features within ERT surveying. According to SSR and GS, expected zones of weakened rock massif were not confirmed directly underneath the superficial landforms, but they were shifted. Based on the SSR and GS measurements, the depicted high-contrast transitions between high- and low-resistivity domains within the ERT profiles were newly identified as possible manifestation of bedrock discontinuities. The results of GPR measurements give only limited information on the sedimentary flysch rocks, due to shallow penetrating depth and locally strong signal attenuation. The combined results of multidisciplinary geophysical surveying confirmed an importance of employing more than one geophysical technique for integrated interpretations of measured data. Integrated interpretations of the measured geophysical data provided a new insight into massif disintegration and the geomorphic origin of the landforms related to the DSL.

  4. Relating Gestures and Speech: An analysis of students' conceptions about geological sedimentary processes (United States)

    Herrera, Juan Sebastian; Riggs, Eric M.


    Advances in cognitive science and educational research indicate that a significant part of spatial cognition is facilitated by gesture (e.g. giving directions, or describing objects or landscape features). We aligned the analysis of gestures with conceptual metaphor theory to probe the use of mental image schemas as a source of concept representations for students' learning of sedimentary processes. A hermeneutical approach enabled us to access student meaning-making from students' verbal reports and gestures about four core geological ideas that involve sea-level change and sediment deposition. The study included 25 students from three US universities. Participants were enrolled in upper-level undergraduate courses on sedimentology and stratigraphy. We used semi-structured interviews for data collection. Our gesture coding focused on three types of gestures: deictic, iconic, and metaphoric. From analysis of video recorded interviews, we interpreted image schemas in gestures and verbal reports. Results suggested that students attempted to make more iconic and metaphoric gestures when dealing with abstract concepts, such as relative sea level, base level, and unconformities. Based on the analysis of gestures that recreated certain patterns including time, strata, and sea-level fluctuations, we reasoned that proper representational gestures may indicate completeness in conceptual understanding. We concluded that students rely on image schemas to develop ideas about complex sedimentary systems. Our research also supports the hypothesis that gestures provide an independent and non-linguistic indicator of image schemas that shape conceptual development, and also play a role in the construction and communication of complex spatial and temporal concepts in the geosciences.

  5. Thirty Sixth Series of the Next Kind of Series

    NARCIS (Netherlands)

    Kok, Wjm


    The subject of the research is ‘difference and repetition,’ an area which bears a direct relationship to Wjm Kok’s practice, in which the production of work always emerges and passes through series. It is also the title of a book by Gilles Deleuze that has been used as source and reference to explic

  6. Lower Cambrian Black Rock Series and Associated Stratiform Deposits in Southern China

    Institute of Scientific and Technical Information of China (English)

    陈南生; 范德廉; 等


    Widespread in more than ten provinces of southern China are the Lower Cambrian black argillaceous-arenaceous rock series consisting of black carbonaceous shales,black carbonaceousargillo-siliceous rocks,black carbonaceous silicolite and black silicolite and black carbonaceous argillaceous siltstone.The Ni,Mo,V,Cu,U,Ba,Ag,P contents of these series are usually several to tens of times higher than their average values in shales.As viewed from lithological sequence,element association and evolution,these black series can be diveided into two types.There occur a variety of deposits in the black rock series,such as phosphorite deposits,Ni-Mo-V polymetal deposits and "Stone coal" seams.According to ore composition,texture and structure,the phosphorite deposits fall into three types,i.e.,thick-bedded,lenticular and nodular,The Ni-Mo-V polymetal deposits,V deposits and reworked sedimentary CU-U-Cd polymetal deposits in terms of their element assiciation and ore genesis.As for the stratiform deposits in the black rock series,three mineralization stages have been recognized,i.e.,the formation of phosphorite deposits,of Ni-Mo polymetal deposits and of V-Cu-U-Cd polymetal deposits as well as of ":stone coal" seams.Evidence strongly suggests that lower organisms have played an important role in mineralization. Our studies indicate that the Lower Cambrian black argillaceous-arenaceous rock series in southern China and their associated stratiform deposits occur generally in the basal parts of a big sedimentary cycle,i.e.,the initial period of a transgression,or in the fine detrital-siliceous formation between two carbonate formatons,formed in a humid climatic zone between two arid ones.As for the environment of deposition,it is suggested that the Lower Cambrian black argillaceous-arenaceous rock series and associated stratiform deposits(excluding thick-bedded phosphorite deposits)were formed mainly in a restricted and poorly-fed sea basin of stagnant shallow water containing

  7. Locations in television drama series

    DEFF Research Database (Denmark)

    Waade, Anne Marit

    , and reflect the growing academic and business interests, respectively, on places in a global media and consumption culture (Falkheimer & Jansson, 2006). Based on empirical location studies of three crime series, Wallander (Yellow Bird, 2008-2012), The Bridge (SVT1 & DR1, 2011-2013) and Dicte (Misofilm/TV2...... in the extra bonus material (Gray, 2010; Waade, 2013), and film tours and film apps become part of the television series’ trans-media franchise (Reijnders, 2011; Thompson, 2007). Location has so far been a practical term describing the place where the series is shot. Ellis (1992) used to see location...

  8. On series of dilated functions

    CERN Document Server

    Berkes, Istvan


    Given a periodic function $f$, we study the almost everywhere and norm convergence of series $\\sum_{k=1}^\\infty c_k f(kx)$. As the classical theory shows, the behavior of such series is determined by a combination of analytic and number theoretic factors, but precise results exist only in a few special cases. In this paper we use connections with orthogonal function theory and GCD sums to prove several new results, improve old ones and also to simplify and unify the theory.

  9. Sedimentary facies and sequential architecture of tide-influenced alluvial deposits : an example from the middle Eocene Capella formation, South-Central Pyrenees, Spain

    NARCIS (Netherlands)

    Cuevas Gozalo, M.C


    The sediments investigated consist of a thick sequence of clastic deposits of middle Eocene age, the Capella Formation. At the time of deposition the sedimentary basin was tectonically active. Tectonic influence in the sedimentary sequence is recognized from angular unconformities, synsedimentary fa

  10. Palaeohydrological controls on sedimentary organic matter in an Amazon floodplain lake, Lake Maracá (Brazil) during the late Holocene

    NARCIS (Netherlands)

    Moreira, L.S.; Moreira-Turcq, P.; Turcq, B.; Cordeiro, R.C.; Kim, J.-H.; Caquineau, S.; Mandeng-Yogo, M.; Macario, K.D.; Sinninghe Damsté, J.S.


    In order to understand the impact of hydrological changes of the Amazon River on sedimentary organic matter (OM) composition in Amazonian floodplain lakes, three sediment cores were collected from Lake Maracá (eastern Amazonia) along a transect from the Amazon River main channel to inland. The cores

  11. Sedimentary cycles in coal and evaporite basins and the reconstruction of Paleozoic climate (Utrecht Studies in Earth Sciences 21)

    NARCIS (Netherlands)

    van den Belt, F.J.G.


    This thesis deals with large-scale processes controlling the formation of sedimentary cycles in coal and evaporite basins and their relation to large-scale fluctuations of Palaeozoic climate. Coal-clastic cycles dominate Pennsylvanian sequences in palaeo-equatorial basins from Euramerica. They forme

  12. Late Cenozoic sedimentary process and its response to the slip history of the central Altyn Tagh fault, NW China

    Institute of Scientific and Technical Information of China (English)

    陈正乐; 张岳桥; 陈宣华; 王小凤; A.S.Ramon; W.B.Zack


    The ENE-striking Altyn Tagh fault (ATF), extending along the northern edge of the Tibetan Plateau, is one of the major important strike-slip faults, and has been known as one of the key areas to debate the eastward extrusion and crustral shortening models of the Tibetan Plateau during and after India-Asia collision. This paper mainly presents new evidence of Late Cenozoic sedimentary process to reconstruct the slip history of the ATF during the Late Cenozoic. Field measurements and laboratory analyses of the sedimentary characteristics in the Late Cenozoic basins in the central Altyn Tagh fault suggest that Late Cenozoic sedimentary sequence should be divided into three units according to facies changes. The paleo-topography reconstruction shows that the sedimentation in these basins was tightly related with the fault, indicating that the ATF has experienced at least three stages of strike slipping in the Late Cenozoic. New geological data from the Late Cenozoic sedimentary basins and the formation of th

  13. Comprehensive constraint on the tectono-sedimentary setting of Late Paleozoic turbidites of the Kamuste area,eastern Junggar, Xinjiang

    Institute of Scientific and Technical Information of China (English)


    Petrography and geochemistry, combined with sedimentation analyses allow for a thorough evaluation of the tectono-sedimentary setting of late Paleozoic turbidites of the Kamuste area eastern Junggar. Sandstones of the Alabiye1) Formation are composed mostly of volcanic and sedimentary detritus with lesser amounts of plagioclase and quartz. They were derived from an undissected magmatic-arc provenance. The geochemistry of sandstone-mudrock suites indicates a fesic-intermediate igneous provenance, and constrains the Alabiye Formation to have derived from a differentiated oceanic-continental margin island-arc tectonic setting. Likewise, geochemistry and sandstone petrography of the Kamuste Formation reflect a mixed provenance signature dominated by magmatic arc, basement uplift, and subduction-complex sources of a differentiated continental-island arc. Sedimentation analysis indicates that the Alabiye and Kamuste formations are two sets of turbidite sequences deposited on a submarine slope and a submarine fan and basin plain respectively. In conclusion, submarine slope turbidite deposition of the Alabiye Formation records the main sedimentary response to the development of early Devonian back-arc basins of the northern Junggar tectonic belt. Submarine fan and basin plain turbidite and background hemipelagic deposition of the Kamuste Formation record the main sedimentary response to the late Early Carboniferous development of an inter-arc relict ocean basin of the eastern Junggar composite terrane.

  14. Tectonic and climatic controls on late quaternary sedimentary processes in a neotectonic intramontane basin. (The Pitalito Basin, South Colombia).

    NARCIS (Netherlands)

    Bakker, J.


    The present study deals with the influence of tectonics and climatic changes on sedimentation patterns in the Quaternary Pitalito Basin (lat. 1°52'N, long. 76°02'W). This intramontane sedimentary basin is 15 km in width and 20 kin in length and is located in the Eastern Cordillera of the southern Co

  15. Measurement of unsaturated hydraulic properties and evaluation of property-transfer models for deep sedimentary interbeds, Idaho National Laboratory, Idaho (United States)

    Perkins, Kimberlie; Johnson, Brittany D.; Mirus, Benjamin B.


    Operations at the Idaho National Laboratory (INL) have the potential to contaminate the underlying Eastern Snake River Plain (ESRP) aquifer. Methods to quantitatively characterize unsaturated flow and recharge to the ESRP aquifer are needed to inform water-resources management decisions at INL. In particular, hydraulic properties are needed to parameterize distributed hydrologic models of unsaturated flow and transport at INL, but these properties are often difficult and costly to obtain for large areas. The unsaturated zone overlying the ESRP aquifer consists of alternating sequences of thick fractured volcanic rocks that can rapidly transmit water flow and thinner sedimentary interbeds that transmit water much more slowly. Consequently, the sedimentary interbeds are of considerable interest because they primarily restrict the vertical movement of water through the unsaturated zone. Previous efforts by the U.S. Geological Survey (USGS) have included extensive laboratory characterization of the sedimentary interbeds and regression analyses to develop property-transfer models, which relate readily available physical properties of the sedimentary interbeds (bulk density, median particle diameter, and uniformity coefficient) to water retention and unsaturated hydraulic conductivity curves.

  16. Sedimentary characteristics and depositional model of a Paleocene-Eocene salt lake in the Jiangling Depression, China (United States)

    Yu, Xiaocan; Wang, Chunlian; Liu, Chenglin; Zhang, Zhaochong; Xu, Haiming; Huang, Hua; Xie, Tengxiao; Li, Haonan; Liu, Jinlei


    We studied the sedimentary characteristics of a Paleocene-Eocene salt lake in the Jiangling Depression through field core observation, thin section identification, scanning electron microscopy, and X-ray diffraction analysis. On the basis of sedimentary characteristics we have summarized the petrological and mineralogical characteristics of the salt lake and proposed 9 types of grade IV salt rhythms. The deposition shows a desalting to salting order of halite-argillaceous-mudstone-mud dolostonemud anhydrock-glauberite-halite. The relationship among grade IV rhythms, water salinity and climate fluctuations was analyzed. Based on the analysis of the relationship between boron content and mudstone color and by combining the mineralogy and sedimentary environment characteristics, we propose that the early and late Paleocene Shashi Formation in the Jiangling Depression was a paleolacustrine depositional environment with a high salt content, which is a representation of the shallow water salt lake depositional model. The middle Paleocene Shashi Formation and the early Eocene Xingouzui Formation were salt and brackish sedimentary environments with low salt content in a deep paleolake, which represents a deep salt lake depositional model.

  17. A cross-system analysis of sedimentary organic carbon in the mangrove ecosystems of Xuan Thuy National Park, Vietnam (United States)

    Tue, Nguyen Tai; Ngoc, Nguyen Thi; Quy, Tran Dang; Hamaoka, Hideki; Nhuan, Mai Trong; Omori, Koji


    A cross-system analysis of bulk sediment composition, total organic carbon (TOC), atomic C/N ratio, and carbon isotope composition (δ 13C) in 82 surface sediment samples from natural and planted mangrove forests, bank and bottom of tidal creeks, tidal flat, and the subtidal habitat was conducted to examine the roles of mangroves in sedimentation and organic carbon (OC) accumulation processes, and to characterize sources of sedimentary OC of the mangrove ecosystem of Xuan Thuy National Park, Vietnam. Sediment grain sizes varied widely from 5.4 to 170.2 μm (mean 71.5 μm), with the fine sediment grain size fraction (mirrored the trend observed in TOC variation. The TOC and δ 13C relationship showed that the factors of microbial remineralization and OC sources controlled the TOC pool of mangrove sediments. The comparison of δ 13C and C/N ratio of sedimentary OC with those of mangrove and marine phytoplankton sources indicated that the sedimentary OC within mangrove forests and the subtidal habitat was mainly composed of mangrove and marine phytoplankton sources, respectively. The application of a simple mixing model showed that the mangrove contribution to sedimentary OC decreased as follows: natural mangrove forest > planted mangrove forest > tidal flat > creek bank > creek bottom > subtidal habitat.


    We measured stable carbon isotope ratios (d13C) in phospholipid fatty acids (PLFAs) to identify the primary carbon source utilized by sedimentary bacteria in Lower Laguna Madre, Texas, which is a seagrass dominated lagoon. Comparisons were made between three differing habitat ty...

  19. Seasonal melting and the formation of sedimentary rocks on Mars, with predictions for the Gale Crater mound

    CERN Document Server

    Kite, Edwin S; Kahre, Melinda A; Wolff, Michael J; Manga, Michael


    A model for the formation and distribution of sedimentary rocks on Mars is proposed. The rate-limiting step is supply of liquid water from seasonal melting of snow or ice. The model is run for a O(10^2) mbar pure CO2 atmosphere, dusty snow, and solar luminosity reduced by 23%. For these conditions snow only melts near the equator, and only when obliquity >40 degrees, eccentricity >0.12, and perihelion occurs near equinox. These requirements for melting are satisfied by 0.01-20% of the probability distribution of Mars' past spin-orbit parameters. Total melt production is sufficient to account for aqueous alteration of the sedimentary rocks. The pattern of seasonal snowmelt is integrated over all spin-orbit parameters and compared to the observed distribution of sedimentary rocks. The global distribution of snowmelt has maxima in Valles Marineris, Meridiani Planum and Gale Crater. These correspond to maxima in the sedimentary-rock distribution. Higher pressures and especially higher temperatures lead to melting...

  20. Complete Genome Sequence of Cryobacterium arcticum Strain PAMC 27867, Isolated from a Sedimentary Rock Sample in Northern Victoria Land, Antarctica (United States)

    Lee, Jaejin; Cho, Ahnna; Yang, Jae Young; Woo, Jusun; Lee, Hong Kum; Hong, Soon Gyu


    Cryobacterium arcticum PAMC 27867, a psychrotolerant, Gram-positive bacterium, was isolated from a sedimentary rock sample collected at Eureka Spurs in northern Victoria Land, Antarctica. Here, we report the genome sequence of C. arcticum PAMC 27867. PMID:27587812

  1. Magnetic properties of different grain-sized particles of sediments from the Okinawa Trough and their relationships to sedimentary environment

    Institute of Scientific and Technical Information of China (English)

    LI Ping; LI Peiying; ZHANG Xiaolong; CAO Chengxiao; XU Xingyong; DU Jun; LIU Lejun


    Multiple magnetic parameters were measured for nine different grain-sized fractions separated from the sediment samples that are representatives of four different sedimentary environments of the Okinawa Trough. Based on the measured results, the contributions of different grain-sized particles to total magnetic susceptibility of bulk sediments, the magnetic mineral assemblage and magnetic domain state as well as their relationships to sedimentary environment were discussed. Our research shows that the magnetic mineral is dominated by magnetite with a small amount of hematite and is primarily in pseudo-single-domain state. That indicates that the different sedimentary environments in the Okinawa Trough have certain correlation in material provenance. The magnetic minerals enrich in different grain-sized particles in response to different sedimentary environments. The contribution of the grain sizes from coarse to fine to coarse and fine to the magnetic susceptibility from the west to the east is in accordance with terrigenous material transportation from continental shelf of the East China Sea to the Okinawa Trough. It also shows difference in magnetic properties as a result of some environmental factors.

  2. High-resolution sedimentary record of hydrocarbon contaminants in a core from the major reaches of the Pearl River, China

    Institute of Scientific and Technical Information of China (English)


    The concentrations and compositions of hydrocarbon contaminants, and molecularmarker indices in modern sediments from a core in the major reaches of the Pearl River were investigated. The sedimentary record of hydrocarbons in the core, in combination with 210pb-dating,was used to reconstruct the pollution history of hydrocarbon pollutants in the Pearl River in the past 100 years.

  3. The potassic sedimentary rocks in Gale Crater, Mars, as seen by ChemCam on board Curiosity (United States)

    Le Deit, L.; Mangold, N.; Forni, O.; Cousin, A.; Lasue, J.; Schröder, S.; Wiens, R. C.; Sumner, D.; Fabre, C.; Stack, K. M.; Anderson, R. B.; Blaney, D.; Clegg, S.; Dromart, G.; Fisk, M.; Gasnault, O.; Grotzinger, J. P.; Gupta, S.; Lanza, N.; Le Mouélic, S.; Maurice, S.; McLennan, S. M.; Meslin, P.-Y.; Nachon, M.; Newsom, H.; Payré, V.; Rapin, W.; Rice, M.; Sautter, V.; Treiman, A. H.


    The Mars Science Laboratory rover Curiosity encountered potassium-rich clastic sedimentary rocks at two sites in Gale Crater, the waypoints Cooperstown and Kimberley. These rocks include several distinct meters thick sedimentary outcrops ranging from fine sandstone to conglomerate, interpreted to record an ancient fluvial or fluvio-deltaic depositional system. From ChemCam Laser-Induced Breakdown Spectroscopy (LIBS) chemical analyses, this suite of sedimentary rocks has an overall mean K2O abundance that is more than 5 times higher than that of the average Martian crust. The combined analysis of ChemCam data with stratigraphic and geographic locations reveals that the mean K2O abundance increases upward through the stratigraphic section. Chemical analyses across each unit can be represented as mixtures of several distinct chemical components, i.e., mineral phases, including K-bearing minerals, mafic silicates, Fe-oxides, and Fe-hydroxide/oxyhydroxides. Possible K-bearing minerals include alkali feldspar (including anorthoclase and sanidine) and K-bearing phyllosilicate such as illite. Mixtures of different source rocks, including a potassium-rich rock located on the rim and walls of Gale Crater, are the likely origin of observed chemical variations within each unit. Physical sorting may have also played a role in the enrichment in K in the Kimberley formation. The occurrence of these potassic sedimentary rocks provides additional evidence for the chemical diversity of the crust exposed at Gale Crater.

  4. Impact of cable bacteria on sedimentary iron and manganese dynamics in a seasonally-hypoxic marine basin

    NARCIS (Netherlands)

    Sulu-Gambari, F; Seitaj, D.; Behrends, T; Banerjee, D.; Meysman, F.J. R.; Slomp, C.P.


    Cable bacteria have recently been identified in various sedimentary 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 r

  5. [Distribution Characteristics of Sedimentary Pigments in the Changjiang Estuary and Zhe-Min Coast and its Implications]. (United States)

    Li, Dong; Yao, Peng; Zhao, Bin; Wang, Jin-peng; Pan, Hui-hui


    Compositions and contents of sedimentary pigments were examined using high performance liquid chromatography in order to discuss the spatial distributions of phytoplankton primary production, phytoplankton functional type and the preservation efficiency of phytoplankton pigments and their influencing factors. The results showed that: chloropigments [Chlorins, including chlorophyll-a (Chl-a) and pheopigments (Pheo-a), such as pheophytin-a (PHtin-a), pheophorbide-a (PHide-a), pPheophytin-a (pPHtin-a), sterol chlorin esters (SCEs) and carotenol chlorin esters (CCEs)] were the major type of sedimentary pigments. The nutrients inputs from Changjiang Diluted Water and upwelling in the Zhe-Min coastal mud area were the major cause for the patchy distribution with high sedimentary chloropigment contents. Carotenoid contents showed no trending changes and exhibited high values in the Changjiang Estuary and Zhe-Min Coasts. Based on the relative proportions of each diagnostic carotenoid to the total diagnostic carotenoids in the sediments, the relative contributions of diatoms, dinoflagellates, prymnesiophytes, prasinophytes, cryptophytes and cyanobacterias in the phytoplankton fuctional types were 48.8% +/- 17.4%, 10.7% +/- 11.5%, 8.1% +/- 7.2%, 18.6% +/- 8.2%, 9.4% +/- 6.4% and 4.3% +/- 3.2%, respectively. The preference for external environmental conditions (e.g., nutrient level and water salinity) was the main cause for the decreasing trends of diatoms and dinoflagellates proportions and the increasing trends of prasinophytes, cryptophytes and cyanobacterias seawards. Based on the spatial distribution of Chl-a/Pheo-a ratios, the higher preservation efficiencies of sedimentary pigments in the coastal regions (e.g., outer edge of maximum turbidity zone in the Changjiang Estuary, mouth of the Hangzhou Bay and upwelling region in the Zhe-Min Coast) were mainly due to the higher sedimentation rate and seasonal occurrences of hypoxia in bottom water, and these regions with

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

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


    The thick (???8 km), regionally extensive section of Neoproterozoic siliciclastic strata (terrigenous detrital succession, TDS) in the central and eastern Great Basin contains sedimentary pyrite characterized by mostly high d34S values (-11.6 to 40.8%, derived from reduction of seawater sulfate, and by markedly radiogenic Pb isotopes ( 207Pb/204Pb derivation of deposit S and Pb from TDS pyrite. Minor element abundances in TDS pyrite (e.g., Pb, Zn, Cu, Ag, and Au) compared to sedimentary and hydrothermal pyrite elsewhere are not noticeably elevated, implying that enrichment in source minerals is not a precondition for intrusion-related metal deposits. Three mechanisms for transferring components of TDS sedimentary pyrite to intrusion-related metal deposits are qualitatively evaluated. One mechanism involves (1) decomposition of TDS pyrite in thermal aureoles of intruding magmas, and (2) aqueous transport and precipitation in thermal or fluid mixing gradients of isotopically heavy S, radiogenic Pb, and possibly other sedimentary pyrite and detrital mineral components, as sulfide minerals in intrusion-related metal deposits. A second mechanism invokes mixing and S isotope exchange in thermal aureoles of Pb and S exsolved from magma and derived from decomposition of sedimentary pyrite. A third mechanism entails melting of TDS strata or assimilation of TDS strata by crustal or mantle magmas. TDS-derived or assimilated magmas ascend, decompress, and exsolve a mixture of TDS volatiles, including isotopically heavy S and radiogenic Pb 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

  7. Spectroscopy, Understanding the Atom Series. (United States)

    Hellman, Hal

    This booklet is one of the "Understanding the Atom" Series. The science of spectroscopy is presented by a number of topics dealing with (1) the uses of spectroscopy, (2) its origin and background, (3) the basic optical systems of spectroscopes, spectrometers, and spectrophotometers, (4) the characteristics of wave motion, (5) the…

  8. Teen Addiction. Current Controversies Series. (United States)

    Winters, Paul A., Ed.

    The Current Controversies series explores social, political, and economic controversies that dominate the national and international scenes today from a variety of perspectives. Recent surveys have shown that, after years of decline, drug use among teenagers has increased during the 1990s, and that alcohol and tobacco use have remained…

  9. Volterra Series Based Distortion Effect

    DEFF Research Database (Denmark)

    Agerkvist, Finn T.


    A large part of the characteristic sound of the electric guitar comes from nonlinearities in the signal path. Such nonlinearities may come from the input- or output-stage of the amplier, which is often equipped with vacuum tubes or a dedicated distortion pedal. In this paper the Volterra series e...

  10. Illegal Immigration. Opposing Viewpoints Series. (United States)

    Cozic, Charles P., Ed.

    Books in the Opposing Viewpoints Series present debates about current issues that can be used to teach critical reading and thinking skills. The variety of opinions expressed in this collection of articles and book excerpts explore many aspects of illegal immigration. Contrary depictions of the aspirations and attitudes of illegal immigrants fuel…

  11. Scholars’ Comments On the Series

    Institute of Scientific and Technical Information of China (English)


    The collection embodies the highest academic standard of China’s research on international politics. The publication of the collection is very timely and the series tells about how China can look upon the world appropriately and how the world can look upon China appropriately.—Fan Jingyi, Professor and Dean of the School of Journalism and Communication, Tsinghua University

  12. Autism: Exceptional Child Bibliography Series. (United States)

    Council for Exceptional Children, Reston, VA. Information Center on Exceptional Children.

    One in a series of over 50 similar selected listings, the bibliography contains 47 items of research reports, conference papers, journal articles, texts, and program guides selected from "Exceptional Child Education Abstracts". Each entry on autism provides bibliographical data, availability information, indexing and retrieval descriptors, and…

  13. Transcendence of Certain Trigonometric Series

    Institute of Scientific and Technical Information of China (English)

    Yao Chen ZHU


    In this paper the transcendence of values of certain trigonometric series with algebraiccoefficients and its derivatives at algebraic points is proved under a genera] condition dependent onlyon the coefficients. The proof of the theorem is based on a criterion for linear independence over anumber field.

  14. A Borderline Random Fourier Series


    Talagrand, Michel


    Consider a mean zero random variable $X$, and an independent sequence $(X_n)$ distributed like $X$. We show that the random Fourier series $\\sum_{n\\geq 1} n^{-1} X_n \\exp(2i\\pi nt)$ converges uniformly almost surely if and only if $E(|X|\\log\\log(\\max(e^e, |X|))) < \\infty$.

  15. Integrated stratigraphy of the Smirra Coring: a new reference sedimentary record for the early Paleogene from the Umbria-Marche Basin (Northern Apennines, Italy) (United States)

    Turtù, Antonio; Lauretano, Vittoria; Catanzariti, Rita; Galeotti, Simone; Lanci, Luca; Moretti, Matteo; Lourens, Lucas J.


    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 large 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 sedimentary 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 Basin, 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

  16. Formation of ophiolite-bearing tectono-sedimentary mélanges in accretionary wedges by gravity driven submarine erosion: Insights from analogue models and case studies (United States)

    Malavieille, Jacques; Molli, Giancarlo; Genti, Manon; Dominguez, Stephane; Beyssac, Olivier; Taboada, Alfredo; Vitale-Brovarone, Alberto; Lu, Chia-Yu; Chen, Chih-Tung


    Orogenic wedges locally present chaotic tectonostratigraphic units that contain exotic blocks of various size, origin, age and lithology, embedded in a sedimentary matrix. The occurrence of ophiolitic blocks, sometimes huge, in such "mélanges" raises questions on (i) the mechanisms responsible for the incorporation of oceanic basement rocks into an accretionary wedge and (ii) the mechanisms allowing exhumation and redeposition of these exotic elements in "mélanges" during wedge growth. To address these questions, we present the results of a series of analogue experiments performed to characterize the processes and parameters responsible for accretion, exhumation and tectonosedimentary reworking of oceanic basement lithospheric fragments in an accretionary wedge. The experimental setup is designed to simulate the interaction between tectonics, erosion and sedimentation. Different configurations are applied to study the impact of various parameters, such as irregular oceanic floor due to structural inheritance, or the presence of layers with contrasted rheology that can affect deformation partitioning in the wedge (frontal accretion vs basal accretion) influencing its growth. Image correlation technique allows extracting instantaneous velocity field, and tracking of passive particles. By retrieving the particle paths determined from models, the pressure-temperature path of mélange units or elementary blocks can be discussed. The experimental results are then compared with observations from ophiolite-bearing mélanges in Taiwan (Lichi and Kenting mélanges) and Raman spectroscopy of carbonaceous material (RSCM) Thermometry data on rocks from the northern Apennines (Casanova mélange). A geological scenario is proposed following basic observations. The tectonic evolution of the retroside of doubly vergent accretionary wedges is mainly controlled by backthrusting and backfolding. The retro wedge is characterized by steep slopes that are prone to gravitational

  17. Sedimentary Environment and Climate Evolution at the Northern Continental Margin of the South China Sea During the Last Glacial Cycle and Holocene (United States)

    Tomczak, M.; Kaiser, J.; Borowka, R. K.; Chen, H.; Zhang, J.; Harff, J.; Qiu, Y.; Witkowski, A.


    Climate, oceanographic and sea level history during last glacial cycle (LGC) and Holocene at the NW continental margin of the South China Sea (SCS) are investigated within the SECEB project. For that purpose two sediment cores (HDQ2 & 83PC) and single-channel seismic sections were selected to serve as a proxy data source for paleoceanographic and paleoclimatic reconstructions. The sedimentary facies is interpreted by multi-proxy approaches considering micropaleontological, sedimentological and geochemical analyses. According to 14C and OSL datings, sediments of shallow water drill core HDQ2 (88.3 m) cover a time span of ca. 115 kyr BP. Seismic images of the sampling site show a series of reflectors which can be correlated with coarse layers of core HDQ2. These layers are interpreted as transgression / regression horizons. Due to the age model it is possible to correlate these horizons with the general sea level dynamics within the SCS as it is displayed in relative sea level excursions for the MIS 5 to 2 from the Sunda Shelf (Hanebuth et al. 2011). Core 83PC (8.6 m) retrieved from the continental slope provide constant record and calm environment. Therefore, this core is used as a source for data proxy for environmental reconstructions. According to δ18O and paleomagnetic analysis, a good age model which indicate age of this core to ca. 110 kyr BP was elaborated and help correlate the paleoenvironmental data with core HDQ2. Alkenones, δ18O, the Mg/Ca ratio, and microfossil proxies serve for paleo-SST curves and monsoon variability reconstructions. δ15N and δ13C indicate nutrient supply to the marine environment. Diatomological analysis outlines the environmental evolution and interrelations between their parameters during the LGC. Interpretation of seismic profiling allowed identification of submarine paleo-delta. It's anticipated that deposited sediments descent from the Hainan Island and allow correlation of the source and sink area.Hanebuth, T.J.J, Voris, H

  18. Sedimentary environment and paleosols of middle Miocene fluvial and lacustrine sediments in central Japan: Implications for paleoclimate interpretations (United States)

    Hatano, Nozomi; Yoshida, Kohki


    Sedimentary facies analysis and description of paleosols were carried out for the middle Miocene Tokiguchi Porcelain Clay Formation (PCF) in central Japan in order to interpret the soil-forming environments during a long hiatus in the Japanese Islands. The sedimentary facies suggests that deposition occurred mainly in a lacustrine environment, with minor channel-fill and debris-flow deposits associated with alluvial fan environments. The coarse-grained sediments, which are inferred to have been deposited in channel-bar and debris-flow deposits, are present only in the marginal area of the sedimentary basin. Mature paleosols are identified in the Tokiguchi PCF, characterized by illuviated clay, identifiable soil horizons including Bt horizons and many in situ plant fossils, and are then similar to Ultisols. Most tree trunk fossils, however, were preserved by burial beneath debris-flow deposits. Most of paleosols formed on lacustrine deposits and were covered by lacustrine clay and silt deposits, without intervening coarse-grained deposits, such as flood-flow deposits. This change of sedimentary facies indicates a dramatic change of hydrologic environment, from stagnant water to entirely desiccated conditions, promoting weathering and soil formation. The relationship between sedimentary facies and Pedotypes, consequently, implies the repetition of specific events, i.e., submergence and emergence of lake bottom, most likely due to formation and drainage of a dammed lake. These isolated events and development of mature paleosols might suggest specific characteristics of middle Miocene weathering conditions, such as seasonally heavy rainfall and/or warm climatic conditions in the Japanese Islands.

  19. Carbon isotopic characteristics and their genetic relationships for individual lipids in plants and sediments from a marsh sedimentary environment

    Institute of Scientific and Technical Information of China (English)

    DUAN Yi; ZHANG Hui; ZHENG Chaoyang; WU Baoxiang; ZHENG Guodong


    The carbon isotopes of individual lipids in herbaceous plants and tree leaves in Ruoergai marsh were measured by the GC-IRMS analytical technique in order to understand the inherent relationships of carbon isotopes between sedimentary and plant lipids from typical marsh environment. The analytical results show that the carbon isotopic compositions of n-alkanes in different kinds of plants differ significantly. Mean δ13C values of n-alkanes in herbaceous plants (-32.2‰―-36.9‰) are 3.3‰ lower than those in woody plant (-27.2‰― -35.0‰). The carbon isotopic compositions of fatty acids in organisms (-30.3‰― -36.2‰) are very similar to those of n-alkanes and the δ13C values for unsaturated fatty acids are within the range of those for saturated fatty acids. The differences in δ13C values between plant lipids are obvious and range from 2.4‰ to 7.8‰. It is observed that the carbon isotopic compositions of sedimentary lipids are closely related to those of plant lipids. The carbon isotopic compositions (-27.0‰―-36.9‰) of n-alkanes, ≥C16 fatty acids, n-alkanols, sterols and n-alkanones in the sediments are similar to those of plant lipids and the carbon isotopic compositions of short-chain sedimentary lipids are similar to those of long-chain sedimentary homologues. These indicate that the sedimentary lipids are derived from high plants. However, the δ13C values of C14:0 and C15:0 fatty acids in the sediments are lighter than those of the same carbon number saturated homologues in plants, reflecting the genetic features partially derived from bacteria. These data provide scientific evidence for carbon isotope-applied research of individual lipids.

  20. Micro-scale Complexity in Iron-Sulfide Phases in Precambrian Sedimentary Rocks Determined by Synchrotron Microprobe Spectroscopy (United States)

    Webb, S.; Johnson, J. E.; Slotznick, S. P.; Roach, C.; Fischer, W. W.


    The record of sedimentary pyrite forms the foundation for most isotope records working to define the coupled evolution and behavior of the ancient iron and sulfur cycles. In order to assess the strengths and limitations of records derived from pyrite-rich rocks (e.g. iron speciation, sulfur isotope ratios), we need to understand more about the processes that form and alter sedimentary pyrite. From samples of the Archean/early Proterozoic Transvaal and middle Proterozoic Belt Supergroups, petrography reveals that what might operationally be called sedimentary pyrite has complex textures that hint at a rich process history of sulfur mineralization. A common limitation of virtually all proxy measurements employed to date is that they operate on 'bulk' samples, typically gram-sized or larger pieces. As such, they lose the ability to relate geochemistry to petrography at the scale of mineral grains. Many of the sedimentary pyrites in the Transvaal Supergroup exhibit complex redox and electronic structures of S and Fe, with crystals of pyrite, pyrrhotite, and sulfate-bearing minerals throughout. Parallel application of multiple techniques on the same samples across micron bases spatial scales, provide an opportunity to diagnose issues resulting from post-depositional alteration of sedimentary rocks. We have integrated light and electron microscopy for petrography, electron microprobe and synchrotron XRF for elemental composition, synchrotron X-ray spectroscopy for redox and chemical state, and secondary ion mass spectrometry (SIMS) for isotopic composition. The coupling of these tools allows in essence "images" of the proxy data at the micrometer scale, giving a wide array of textural and mineralogical information designed to inform and untangle the complicated histories of these early Precambrian rocks.

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

    Directory of Open Access Journals (Sweden)

    Ziliang Liu

    Full Text Available 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

  2. Flow regulation manipulates contemporary seasonal sedimentary dynamics in the reservoir fluctuation zone of the Three Gorges Reservoir, China. (United States)

    Tang, Qiang; Bao, Yuhai; He, Xiubin; Fu, Bojie; Collins, Adrian L; Zhang, Xinbao


    Since the launch of the Three Gorges Dam on the Yangtze River, a distinctive reservoir fluctuation zone has been created and significantly modified by regular dam operations. Sediment redistribution within this artificial landscape differs substantially from that in natural fluvial riparian zones, due to a specific hydrological regime comprising steps of water impoundment with increasing magnitudes and seasonal water level fluctuation holding a range of sediment fluxes. This study reinterpreted post-dam sedimentary dynamics in the reservoir fluctuation zone by stratigraphy determination of a 345-cm long sediment core, and related it to impact of the hydrological regime. Seasonality in absolute grain-size composition of suspended sediment was applied as a methodological basis for stratigraphic differentiation. Sedimentary laminations with relatively higher proportions of sandy fractions were ascribed to sedimentation during the dry season when proximal subsurface bank erosion dominates source contributions, while stratigraphy with a lower proportion of sandy fractions is possibly contributed by sedimentation during the wet season when distal upstream surface erosion prevails. Chronology determination revealed non-linear and high annual sedimentation rates ranging from 21.7 to 152.1cm/yr. Although channel geomorphology may primarily determine the spatial extent of sedimentation, seasonal sedimentary dynamics was predominantly governed by the frequency, magnitude, and duration of flooding. Summer inundation by natural floods with enhanced sediment loads produced from upstream basins induced higher sedimentation rates than water impoundment during the dry season when distal sediment supply was limited. We thus conclude that flow regulation manipulates contemporary seasonal sedimentary dynamics in the reservoir fluctuation zone, though little impact on total sediment retention rate was detected. Ongoing reductions in flow and sediment supply under human disturbance may

  3. Analysis of series resonant converter with series-parallel connection (United States)

    Lin, Bor-Ren; Huang, Chien-Lan


    In this study, a parallel inductor-inductor-capacitor (LLC) resonant converter series-connected on the primary side and parallel-connected on the secondary side is presented for server power supply systems. Based on series resonant behaviour, the power metal-oxide-semiconductor field-effect transistors are turned on at zero voltage switching and the rectifier diodes are turned off at zero current switching. Thus, the switching losses on the power semiconductors are reduced. In the proposed converter, the primary windings of the two LLC converters are connected in series. Thus, the two converters have the same primary currents to ensure that they can supply the balance load current. On the output side, two LLC converters are connected in parallel to share the load current and to reduce the current stress on the secondary windings and the rectifier diodes. In this article, the principle of operation, steady-state analysis and design considerations of the proposed converter are provided and discussed. Experiments with a laboratory prototype with a 24 V/21 A output for server power supply were performed to verify the effectiveness of the proposed converter.

  4. Tectonics of Chukchi Sea Shelf sedimentary basins and its influence on petroleum systems (United States)

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


    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

  5. The volcanic-sedimentary sequence of the Lousal deposit, Iberian Pyrite Belt (Portugal) (United States)

    Rosa, Carlos; Rosa, Diogo; Matos, Joao; Relvas, Jorge


    The Iberian Pyrite Belt (IPB) is a massive sulfide province that is located in the south of Portugal and Spain, and hosts more than 90 massive sulfide deposits that amount to more than 1850 million metric tonnes of sulfide ore (Tornos, 2006). The ore deposits size, vary from ~1Mt to >100Mt (e.g. Neves Corvo and Aljustrel in Portugal, and Rio Tinto and Tharsis in Spain). The ore deposits are hosted by a submarine sedimentary and volcanic, felsic dominated, succession that constitutes the Upper Devonian to Lower Carboniferous Volcanic and Sedimentary Complex (VSC). The VSC ranges in thickness from approximately 600 to 1300 m (Tornos 2006). The VSC overlies the Phyllite-Quartzite Group (PQ) (Upper Devonian, base unknown) and is overlain by the Baixo Alentejo Flysch Group (Lower to Upper Carboniferous). The Lousal massive sulfide deposit is located in the western part of the IPB and occurs mostly interbedded with black mudstone. The VSC sequence at Lousal mine consists of a mudstone and quartzite sequence (PQ Group) in the lower part of the succession, over which a thick sequence of rhyolitic lavas (>300 m) occurs. Above the rhyolitic lavas there is a thick sequence of black and grey mudstone that hosts the massive sulfide ore bodies, and a rhyolitic sill. The upper part of the VSC sequence consists of a thick mudstone interval that hosts two thick basaltic units, locally with pillows. The rhyolites have small coherent cores, locally with flow bands, that grade to surrounding massive clastic intervals, with large lateral extent. The clasts show jigsaw-fit arrangement in many places and have planar or curviplanar margins and locally are perlitic at the margin. The top contact of these units is in most locations not exposed, which makes difficult to interpret the mode of emplacement. However, the thick clastic intervals, above described, are in accordance with quenching of volcanic glass with abundant water and therefore indicate that quenching of the rhyolites was the

  6. The anthropogenic change of sedimentary system recored to short core in brackish Lake Ogawara, North Japan (United States)

    Nagashima, A.; Seto, K.; yamada, K.; Yonenobu, H.


    The sedimentary environment of brackish lake is fluctuated by the effect of sediment flux from rivers, tidal, climate change, and human activities. Each brackish lake has a specific character. The Lake Ogawara is located in east part of Aomori Prefecture, is connected to the Pacific Ocean through Takase River. In this study, we performed the investigation in the Lake Ogawara at 2011, to clarify a characteristic of recent sedimentary environments. In addition, the short coring at 2012 is performed to show a changes of sedimentary environments. The investigation is made up of 110 detailed sampling localities in grid and 100 water quality measurement sites in a traverse line through the lake system. In addition, the short cores were sampled at sites of Og20, 33, 64, 84, 95 and 97. The water column of Lake Ogawara divided into 3 water masses, as an epilimnion (0-10m), a metalimnion (10-18m), and a hypolimnion (deeper than 18m). The environments in metalimnion and hypolimnion show the anoxic to euxinic condition. The upper part of the metalimnion shows pycnocline dependent on water temperature and salinity, and the lower part shows pycnocline dependent on mainly salinity. Surface sediments are observed well-sorted sand shallower than 10m, and black organic mud with lamination deeper than it depth. As a result of CNS element anaysis of surface sediments, the total organic carbon (TOC) contens increase toward deep, and show very high value (around 8%) in metalimnion and hypolimnion. Total sulfur (TS) content shows 1-2% of values deeper than metalimnion. In spite of euxinic condition, TOC/TS ratio is high in comparison with the normal marine. This suggests the exhaustion of metal ions such as iron or undersupply of sulfate ion. In Og84, 97 cores, the upper part shows the black (L*=6). But lower part shows relative high lightness (L*=15 to 20). The mean grain size of the upper part (black layer) is 6.5φ, the lower part shows the 8.0φ. TOC contents shows the around 7% in

  7. Controls and variability of solute and sedimentary fluxes in Antarctic and sub-Antarctic Environments (United States)

    Zwolinski, Zbigniew


    The currently prepared SEDIBUD Book on "Source-to-Sink Fluxes in Undisturbed Cold Environments" (edited by Achim A. Beylich, John C. Dixon and Zbigniew Zwolinski and published by Cambridge University Press) is summarizing and synthesizing the achievements of the International Association of Geomorphologists` (I.A.G./A.I.G.) Working Group SEDIBUD (Sediment Budgets in Cold Environments), which has been active since 2005 ( The book comprises five parts. One of them is part about sub-Antarctic and Antarctic Environments. This part "Sub-Antarctic and Antarctic Environments" describes two different environments, namely oceanic and continental ones. Each part contains results of research on environmental drivers and rates of contemporary solute and sedimentary fluxes in selected sites. Apart from describing the environmental conditions of the whole continent of Antarctica and sub-Antarctic islands (Zb.Zwolinski, M.Kejna, A.N.Lastochkin, A.Zhirov, S.Boltramovich) this part of the book characterizes terrestrial polar oases free from multi-year ice and snow covers (Zb.Zwolinski). The detailed results of geoecological and sedimentological research come from different parts of Antarctica. Antarctic continental shelf (E.Isla) is an example of sub-Antarctic oceanic environment. South Shetlands, especially King George Island (Zb.Zwolinski, M.Kejna, G.Rachlewicz, I.Sobota, J.Szpikowski), is an example of sub-Antarctic terrestrial environment. Antarctic Peninsula (G.Vieira, M.Francelino, J.C.Fernandes) and surroundings of McMurdo Dry Valleys (W.B.Lyons, K.A.Welch, J.Levy, A.Fountain, D.McKnight) are examples of Antarctic continental environments. The key goals of the Antarctic and sub-Antarctic book chapters are following: (i) identify the main environmental drivers and rates of contemporary solute and sedimentary fluxes, and (ii) model possible effects of projected climate change on solute and sedimentary fluxes in cold climate environments

  8. Geochemical Modeling of Evaporation Processes on Mars: Insight From the Sedimentary Record at Meridiani Planum (United States)

    Tosca, N. J.; McLennan, S. M.


    The Opportunity rover's analysis of an impure evaporite component present in the Martian sedimentary record reveals a unique geochemical system. The evaporation of basaltic weathering fluids is a process which is rare on Earth, but is likely to have played a major role in the formation of sedimentary rocks at Meridiani Planum. Adequately modeling the evaporation processes in this system must involve adding additional components to current thermodynamic models, namely Fe(II) and Fe(III). The goals of this study are to: (1) develop a thermodynamic database suitable for modeling evaporation of basaltic weathering fluids in the Meridiani system and (2) to apply the model to experimental fluid data obtained in our laboratory from weathering synthetic Martian basalt, which will allow for the testing of hypotheses related to the geochemical evolution of the Meridiani site. The evaporation of these fluids is simulated using an expanded version of the Harvie-Moller-Weare model which employs Pitzer's ion interaction approach in calculating activity coefficients in high ionic strength solutions. This model has been expanded using recent data to include Fe(II) and Fe(III). Although a full set of experimentally-derived data allowing the inclusion of Fe(III) into such models is not yet available, an adequate set of interaction parameters was built, based on viable assumptions and substitutions using analog data (e.g., Al3+, Ga3+, Cr3+). The accuracy of the thermodynamic model in predicting Fe(II) and Fe(III) activities in a multi-component system can be assessed. This is accomplished by comparing calculated Eh values (proportional to aFe2+/aFe3+) to those measured in the field from high ionic strength acid mine waters containing all of the relevant components of the model. The agreement between calculated and observed values suggests that the model calculations are adequate for reaction path calculations. New thermodynamic data for several Fe(II) and/or Fe(III) containing

  9. Preliminary study of Precambrian integration with tectonic events in brazilian sedimentary basins (Updated); Estudo preliminar de integracao do Pre-Cambriano com os eventos tectonicos das bacias sedimentares brasileiras (Atualizacao)

    Energy Technology Data Exchange (ETDEWEB)

    Cordani, Umberto G. [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Geociencias. Centro de Pesquisas Geocronologicas], Email:; Neves, Benjamim Bley de Brito [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Geociencias. Dept. de Mineralogia e Geotectonica], Email:; Thomaz Filho, Antonio [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Fac. de Geologia. Dept. de Estratigrafia e Paleontologia], Email:


    The article 'Preliminary study of Precambrian integration with tectonic events in Brazilian sedimentary basins,' by U. G. Cordani, B. B. Brito-Neves, R. A. Fuck, R. Porto, A. Thomaz-Filho and F. M. B. da Cunha, was published in PETROBRAS Petroleum Technical Science Series (Serie Ciencia Tecnica Petroleo da PETROBRAS) in 1984 and is being reissued by PETROBRAS Geosciences Bulletin. Naturally, the work requires many updates in the light of geosciences' progress in Brazil over the past 26 years. In these comments, numerous reflections have been addressed at short notice, but nevertheless considered appropriate, to occupy space conceded by the publishers for an assessment of the original work. In principle, only the latest summaries and newer published items on the topic have been consulted and commented. For this reason, it was decided to 'overlook' a number of important references on this issue, apologizing to the authors of omitted relevant works. The study, conducted in the early '80s, was based on the knowledge at the time regarding the tectonic evolution of the South American basement; an examination of PETROBRAS subsurface data in Brazilian sedimentary basins and the study of the Company's core samples obtained from perforations which reached the basement. Since then, great advances have been made in understanding the Brazilian territory tectonic evolution and important geophysical data collected regarding its sedimentary basins. On the other hand, there are virtually no recent perforations of the interior Cratonic basins. Moreover, in the marginal and offshore basins, many wells have not reached the basement. Therefore, in these comments, we sought to review the original study's interpretations and confirm the relevant geological knowledge added in recent decades, in the range of the original work. In this article, we try to follow the same structural sequence of the original text, giving the reader a better understanding

  10. Tephrostratigraphy during 3000 years recorded in the sedimentary sequence of Beppu Bay, central Kyushu, Japan (United States)

    Takemura, K.; Yamada, K.; Kuwae, M.; Yamamoto, M.; Danhara, T.


    The tephrostratigraphy around Beppu Bay, central Japan, is investigated using a 9m-long sedimentary core (KT09-3) collected in 2009 with a piston corer. Beppu Bay is located to the east of active volcanic region in Kyushu Island in southwest Japan. Eruptive history of their active volcanoes and widespread tephra records may be preserved in the sedimentary sequence in bay environment. A method to determine the down-hole content of volcanic glass was used in this study. This method consists of four steps: (1) continuous measurement of magnetic susceptibility with lithological observation of sediments, (2) systematic separation of the volcanic glass particles from samples taken at close intervals, and the determination of relative concentration; (3) mineral assemblages counted in the size of 63-125 micro meter fraction; (4) precise measurement of the refractive indices of the separated glass particles. A refractive index measuring system (RIMS) based on the thermal immersion method permitted quick and accurate measurement of the refractive index of a large number of samples. Core (KT09-3) is one of fourteen piston and gravity cores which were retrieved at the center of the basin. Correlation of cores was conducted using sand and silt seams related by events such as turbidite or flood or volcanic ash air fall, and the age-depth model was created by wiggle-matching of forty-two AMS radiocarbon dates from bivalve mollusk shells and excess Pb-210 and Cs-137 concentrations (Kuwae et al., 2012). The sedimentation rates were 230-300 cm/ky. Core is composed of massive diatomaceous clays with 18 event sediments of coarse fractions. Two distinct volcanic ash horizons and several cryptically deposited horizons are found within the sequence. Upper distinct volcanic ash of 509.2 cm depth is composed of many volcanic glasses and heavy minerals of Opx and Cpx with GHb and BHb. Most of volcanic glasses have characteristic high refractive index of about 1.559. This tephra is

  11. Earthquake ground motion prediction for real sedimentary basins: which numerical schemes are applicable? (United States)

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


    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

  12. The Geomechanics of CO2 Storage in Deep Sedimentary Formations

    Energy Technology Data Exchange (ETDEWEB)

    Rutqvist, Jonny [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)


    This study provides a review of the geomechanics and modeling of geomechanics associated with geologic carbon storage (GCS), focusing on storage in deep sedimentary formations, in particular saline aquifers. The paper first introduces the concept of storage in deep sedimentary formations, the geomechanical processes and issues related with such an operation, and the relevant geomechanical modeling tools. This is followed by a more detailed review of geomechanical aspects, including reservoir stress-strain and microseismicity, well integrity, caprock sealing performance, and the potential for fault reactivation and notable (felt) seismic events. Geomechanical observations at current GCS field deployments, mainly at the In Salah CO2 storage project in Algeria, are also integrated into the review. The In Salah project, with its injection into a relatively thin, low-permeability sandstone is an excellent analogue to the saline aquifers that might be used for large scale GCS in parts of Northwest Europe, the U.S. Midwest, and China. Some of the lessons learned at In Salah related to geomechanics are discussed, including how monitoring of geomechanical responses is used for detecting subsurface geomechanical changes and tracking fluid movements, and how such monitoring and geomechanical analyses have led to preventative changes in the injection parameters. Recently, the importance of geomechanics has become more widely recognized among GCS stakeholders, especially with respect to the potential for triggering notable (felt) seismic events and how such events could impact the long-term integrity of a CO2 repository (as well as how it could impact the public perception of GCS). As described in the paper, to date, no notable seismic event has been reported from any of the current CO2 storage projects, although some unfelt microseismic activities have been detected by geophones. However, potential future commercial GCS operations from large

  13. Differential preservation in the geologic record of intraoceanic arc sedimentary and tectonic processes (United States)

    Draut, Amy; Clift, Peter D.


    Records of ancient intraoceanic arc activity, now preserved in continental suture zones, are commonly used to reconstruct paleogeography and plate motion, and to understand how continental crust is formed, recycled, and maintained through time. However, interpreting tectonic and sedimentary records from ancient terranes after arc–continent collision is complicated by preferential preservation of evidence for some arc processes and loss of evidence for others. In this synthesis we examine what is lost, and what is preserved, in the translation from modern processes to the ancient record of intraoceanic arcs. Composition of accreted arc terranes differs as a function of arc–continent collision geometry. ‘Forward-facing’ collision can accrete an oceanic arc on to either a passive or an active continental margin, with the arc facing the continent and colliding trench- and forearc-side first. In a ‘backward-facing’ collision, involving two subduction zones with similar polarity, the arc collides backarc-first with an active continental margin. The preservation of evidence for contemporary sedimentary and tectonic arc processes in the geologic record depends greatly on how well the various parts of the arc survive collision and orogeny in each case. Preservation of arc terranes likely is biased towards those that were in a state of tectonic accretion for tens of millions of years before collision, rather than tectonic erosion. The prevalence of tectonic erosion in modern intraoceanic arcs implies that valuable records of arc processes are commonly destroyed even before the arc collides with a continent. Arc systems are most likely to undergo tectonic accretion shortly before forward-facing collision with a continent, and thus most forearc and accretionary-prism material in ancient arc terranes likely is temporally biased toward the final stages of arc activity, when sediment flux to the trench was greatest and tectonic accretion prevailed. Collision geometry

  14. Random time series in astronomy. (United States)

    Vaughan, Simon


    Progress in astronomy comes from interpreting the signals encoded in the light received from distant objects: the distribution of light over the sky (images), over photon wavelength (spectrum), over polarization angle and over time (usually called light curves by astronomers). In the time domain, we see transient events such as supernovae, gamma-ray bursts and other powerful explosions; we see periodic phenomena such as the orbits of planets around nearby stars, radio pulsars and pulsations of stars in nearby galaxies; and we see persistent aperiodic variations ('noise') from powerful systems such as accreting black holes. I review just a few of the recent and future challenges in the burgeoning area of time domain astrophysics, with particular attention to persistently variable sources, the recovery of reliable noise power spectra from sparsely sampled time series, higher order properties of accreting black holes, and time delays and correlations in multi-variate time series.

  15. Random time series in Astronomy

    CERN Document Server

    Vaughan, Simon


    Progress in astronomy comes from interpreting the signals encoded in the light received from distant objects: the distribution of light over the sky (images), over photon wavelength (spectrum), over polarization angle, and over time (usually called light curves by astronomers). In the time domain we see transient events such as supernovae, gamma-ray bursts, and other powerful explosions; we see periodic phenomena such as the orbits of planets around nearby stars, radio pulsars, and pulsations of stars in nearby galaxies; and persistent aperiodic variations (`noise') from powerful systems like accreting black holes. I review just a few of the recent and future challenges in the burgeoning area of Time Domain Astrophysics, with particular attention to persistently variable sources, the recovery of reliable noise power spectra from sparsely sampled time series, higher-order properties of accreting black holes, and time delays and correlations in multivariate time series.

  16. Fourier series and orthogonal functions

    CERN Document Server

    Davis, Harry F


    This incisive text deftly combines both theory and practical example to introduce and explore Fourier series and orthogonal functions and applications of the Fourier method to the solution of boundary-value problems. Directed to advanced undergraduate and graduate students in mathematics as well as in physics and engineering, the book requires no prior knowledge of partial differential equations or advanced vector analysis. Students familiar with partial derivatives, multiple integrals, vectors, and elementary differential equations will find the text both accessible and challenging.

  17. Sedimentary fluxes and different dispersion mechanism of the clay sediments in the Adriatic Basin; Flussi sedimentari e differenti meccanismi di dispersione dei sedimenti argillosi nel Bacino Adriatico

    Energy Technology Data Exchange (ETDEWEB)

    Tomadin, L. [Urbino Univ., Urbino (Italy). Ist. di Geodinamica e Sedimentologia


    dispersione longitudinale dei materiali fini nel bacino. Essa dipende dalla circolazione ciclonica delle correnti marine nell'Adriatico, che favorisce lo sviluppo di importanti flussi sedimentari. Lungo le coste italiane, due flussi principali caratterizzano il trasporto di materiali argillosi verso SE: un flusso Appenninico costiero ed un flusso Padano di mare aperto parallelo al primo. Un flusso Albanese subordinato si muove invece verso NO e convoglia sedimenti fini lungo le coste orientali del bacino. Anche altri meccanismi di trasporto giocano un ruolo importante nella dispersione dei sedimenti argillosi nell'ambiente marino. Essi si affiancano, in genere, all'azione dominante di trasporto legata alla circolazione generale delle acque. Nell'Adriatico settentrionale, la diffusione del grande pennacchio torbido del Po influisce notevolmente sulla distribuzione dei sedimenti. Al crescere della profondita' delle acque, correnti di gradiente di varia origine agiscono frequentemente in varie parti del bacino, contribuendo al movimento dei materiali in sospensione e favorendo flussi longitudinali di sedimenti argillosi. Nell'Adriatico meridionale, oltre all'azione dei flussi principali, correnti torbide trasversali al bacino trasportano materiali argillosi dalla piattaforma pugliese e da quella albanese-montenegrina verso il bacino batiale.

  18. Extensional deformation of the Guadalquivir Basin: rate of WSW-ward tectonic displacement from Upper Tortonian sedimentary rocks (United States)

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


    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


    Directory of Open Access Journals (Sweden)

    V. G. Bakhmutov


    Full Text Available Paleomagnetic data are the priority source of information for global paleotectonic reconstructions representing horizontal movements of the crustal blocks. Upon receipt of new paleomagnetic data, kinematic models of the East European platform in the Paleozoic are regularly revised and improved. The article presents results of the paleomagnetic study of sedimentary gray-colored and red beds of the Silurian and Lower Devonian sequences located in the Dniester river basin, Podolia region, SW Ukraine. The study covered 17 outcrops that are stratigraphically correlated with the Wenlock, Ludlow, Pridoli states of the Sillurian and the Lochkovian stage of the Devon. Over 400 samples of grey limestone, argillite, dolomite, red limestone and sandstone were analyzed, and two components of natural remnant magnetization (NRM were revealed. The first component with SSW declination and negative inclination is revealed in the majority of the samples during AF- and T-magnetic cleaning. Its pole positions, that are calculated separately for each series, are trending to the Permian segment of the apparent polar wander path (APWP published by Torsvik et al. [2012] for Baltica / Stable Europe. Considering its chemical origin, this NRM component is related to formation of authigenic minerals due to rock remagnetization. The second component is revealed only in some samples taken from the red beds (during thermal demagnetization in the range of unblocking temperatures from 590 to 690 °С and in few samples of grey limestone (in AF fields from 30 to 70 mT or in the range of unblocking temperatures from 300 to 460 °С. This component has SW declination and positive inclination, goes to the origin of coordinates of the diagrams, and has all the indicators of primary magnetization of sediments. Calculated positions of the poles (0 ºS and 329 ºE for grey limestone of the Tiverskaya series, 2.3 °S and 338.4 °E for red beds of the Dniestrovskaya series, etc. are well

  20. A reaction kinetic approach to the temperature-time history of sedimentary basins (United States)

    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.

  1. Three wave mixing test of hyperelasticity in highly nonlinear solids: sedimentary rocks. (United States)

    D'Angelo, R M; Winkler, K W; Johnson, D L


    Measurements of three-wave mixing amplitudes on solids whose third order elastic constants have also been measured by means of the elasto-acoustic effect are reported. Because attenuation and diffraction are important aspects of the measurement technique results are analyzed using a frequency domain version of the KZK equation, modified to accommodate an arbitrary frequency dependence to the attenuation. It is found that the value of beta so deduced for poly(methylmethacrylate) (PMMA) agrees quite well with that predicted from the stress-dependent sound speed measurements, establishing that PMMA may be considered a hyperelastic solid, in this context. The beta values of sedimentary rocks, though they are typically two orders of magnitude larger than, e.g., PMMA's, are still a factor of 3-10 less than those predicted from the elasto-acoustic effect. Moreover, these samples exhibit significant heterogeneity on a centimeter scale, which heterogeneity is not apparent from a measurement of the position dependent sound speed.

  2. Sedimentary processes and development of the Zenisu deep-sea channel, Philippine Sea

    Institute of Scientific and Technical Information of China (English)

    WUShiguo; SakamotoIzumi


    Zenisu deep-sea channel originated from a volcanic arc region, Izu-Ogasawara Island Arc, and vanished in the Shikoku Basin of the Philippine Sea. According to the swath bathymetry, the deep-sea channel can be divided into three segments. They are Zenisu canyon, E-W fan channel and trough-axis channel. A lot of volcanic detritus were deposited in the Zenisu Trough via the deep-sea channel because it originated from volcanic arc settings. On the basis of the swath bathymetry, submersible and seismic reflection data, the deposits are characterized by turbidite and debrite deposits as those in the other major deep-sea channels. Erosion or few sediments were observed in the Zenisu canyon,whereas a lot of turbidites and debrites occurred in the E-W channel and trough axis channel. Cold seep communities,active fault and fluid flow were discovered along the lower slope of the Zenisu Ridge. Vertical sedimentary sequences in the Zenisu Trough consist of the four post-rift sequence units of the Shikoku Basin, among which Units A and B are two turbidite units. The development of Zenisu canyon is controlled by the N-S shear fault, the E-W fan channel is related to the E-W shear fault, and the trough-axis channel is related to the subsidence of central basin.

  3. Sedimentary processes and development of the Zenisu deep-sea channel, Philippine Sea

    Institute of Scientific and Technical Information of China (English)


    Zenisu deep-sea channel originated from a volcanic arc region, Izu-Ogasawara Island Arc, and vanished in the Shikoku Basin of the Philippine Sea. According to the swath bathymetry, the deep-sea channel can be divided into three segments. They are Zenisu canyon, E-W fan channel and trough-axis channel. A lot of volcanic detritus were deposited in the Zenisu Trough via the deep-sea channel because it originated from volcanic arc settings. On the basis of the swath bathymetry, submersible and seismic reflection data, the deposits are characterized by turbidite and debrite deposits as those in the other major deep-sea channels. Erosion or few sediments were observed in the Zenisu canyon, whereas a lot of turbidites and debrites occurred in the E-W channel and trough axis channel. Cold seep communities, active fault and fluid flow were discovered along the lower slope of the Zenisu Ridge. Vertical sedimentary sequences in the Zenisu Trough consist of the four post-rift sequence units of the Shikoku Basin, among which Units A and B are two turbidite units. The development of Zenisu canyon is controlled by the N-S shear fault, the E-W fan channel is related to the E-W shear fault, and the trough-axis channel is related to the subsidence of central basin.

  4. A discontinuum-based model to simulate compressive and tensile failure in sedimentary rock

    Institute of Scientific and Technical Information of China (English)

    T. Kazerani


    The study presented in this paper discusses a discontinuum-based model for investigating strength and failure in sedimentary rocks. The model has been implemented by UDEC to incorporate an innovative orthotropic cohesive constitutive law for contact. To reach this purpose, a user-defined model has been established by creating dynamic link libraries (DLLs) and attaching them into the code. The model repro-duces rock material by a dense collection of irregular-sized deformable particles interacting at their cohesive boundaries which are viewed as flexible contacts whose stress-displacement law is assumed to control the fracture and the fragmentation behaviours of the material. The model has been applied to a sandstone. The individual and interactional effects of the microstructural parameters on the mate-rial compressive and tensile failure responses have been examined. In addition, the paper presents a new methodical calibration procedure to fit the modelling microparameters. It is shown that the model can successfully reproduce the rock mechanical behaviour quantitatively and qualitatively. The study also shows how discontinuum-based modelling can be used to characterize the relation between the microstructural parameters and the macro-scale properties of a material.

  5. Evaluation of Five Sedimentary Rocks Other Than Salt for Geologic Repository Siting Purposes

    Energy Technology Data Exchange (ETDEWEB)

    Croff, A.G.; Lomenick, T.F.; Lowrie, R.S.; Stow, S.H.


    The US Department of Energy (DOE), in order to increase the diversity of rock types under consideration by the geologic disposal program, initiated the Sedimary ROck Program (SERP), whose immediate objectiv eis to evaluate five types of secimdnary rock - sandstone, chalk, carbonate rocks (limestone and dolostone), anhydrock, and shale - to determine the potential for siting a geologic repository. The evaluation of these five rock types, together with the ongoing salt studies, effectively results in the consideration of all types of relatively impermeable sedimentary rock for repository purposes. The results of this evaluation are expressed in terms of a ranking of the five rock types with respect to their potential to serve as a geologic repository host rock. This comparative evaluation was conducted on a non-site-specific basis, by use of generic information together with rock evaluation criteria (RECs) derived from the DOE siting guidelines for geologic repositories (CFR 1984). An information base relevant to rock evaluation using these RECs was developed in hydrology, geochemistry, rock characteristics (rock occurrences, thermal response, rock mechanics), natural resources, and rock dissolution. Evaluation against postclosure and preclosure RECs yielded a ranking of the five subject rocks with respect to their potential as repository host rocks. Shale was determined to be the most preferred of the five rock types, with sandstone a distant second, the carbonate rocks and anhydrock a more distant third, and chalk a relatively close fourth.

  6. Historical reconstruction of anthropogenic mercury input from sedimentary records: Yeongsan Estuary, South Korea (United States)

    Williams, Joshua; Dellapenna, Timothy; Louchouarn, Patrick; Lee, Guan-hong


    The rapid economic growth of the Republic of Korea (S. Korea) within the last half-century has resulted in a pronounced increase in anthropogenic Hg emission from coal combustion, oil refining, cement production, and waste incineration. The record of increasing atmospheric sources have been investigated with a historical reconstruction of Hg accumulation in 30 sediment cores collected from the Yeongsan Estuary. Within the last several decades, this region has undergone severe anthropogenic alteration, including the construction of an estuarine dam forming the Yeongsan Lake, and installation of numerous seawalls that eliminated vast tidal flats and restricted estuarine circulation. Total mercury concentrations (T-Hg) measured in sediments deposited after 1980 (23.2 ± 9.6 ng g-1; n = 273), were significantly higher than those reported for pre-industrial sediments (i.e. background values: 8.6 ± 2.7 ng g-1; n = 274). An extensive survey of surface samples show that T-Hg concentrations are highest above the dam, with a gradient to lower values further offshore. The concomitant timing of enrichment of T-Hg within the sedimentary record and increased National emissions in Korea suggests that regional sources dominate the input to the Yeongsan Estuary. This indicates that with sufficient regional historic emission data, T-Hg might be utilized as a geochronologic tool to aid in corroborating traditional radioisotopic methods.

  7. Sedimentary-tectonic evolution from late Palaeozoic to Triassic in south of North China block

    Energy Technology Data Exchange (ETDEWEB)

    Chen, S. [University of Petroleum, Dongying (China). Dept of Resource


    The sedimentary facies of some typical profiles as in Hancheng, Jiyuan, Denfeng and Huainan, and the characteristic of regional palaeogeography in the south of North China block were researched. The result shows that the research area had an evolution from the epeiric sea to a lake basin during Palaeozoic to Triassic. This transition was controlled by the collision progeny of Qinling orogenic belt directly. The collision began along the Shangnan-Zhenping-Tongbai line, making the south of North China block compressed and subsided, and transferred from a structural high land to an epeiric sea in Late Carboniferous. The western part of North Qinling began to uplift and became a source of terrigenous clastic sediments to North China basin. In the Permian, the compression strengthened further and the North Qinling-North Huaiyang structural belt uplifted, making the epeiric sea transits to a marginal lake basin. In the Triassic, the Qinling orogenic belt uplifted rapidly and the large scale depression lake basin developed in its north side, and the centre of the basin also transferred to the orogenic belt in the Late Triassic. 7 refs., 4 figs.

  8. Late Pleistocene carnivores (Carnivora: Mammalia) from a cave sedimentary deposit in northern Brazil. (United States)

    Rodrigues, Shirlley; Avilla, Leonardo S; Soibelzon, Leopoldo H; Bernardes, Camila


    The Brazilian Quaternary terrestrial Carnivora are represented by the following families: Canidae, Felidae, Ursidae, Procyonidae Mephitidae and Mustelidae. Their recent evolutionary history in South America is associated with the uplift of the Panamanian Isthmus, and which enabled the Great American Biotic Interchange (GABI). Here we present new fossil records of Carnivora found in a cave in Aurora do Tocantins, Tocantins, northern Brazil. A stratigraphical controlled collection in the sedimentary deposit of the studied cave revealed a fossiliferous level where the following Carnivora taxa were present: Panthera onca, Leopardus sp., Galictis cuja, Procyon cancrivorus, Nasua nasua and Arctotherium wingei. Dating by Electron Spinning Resonance indicates that this assemblage was deposited during the Last Glacial Maximum (LGM), at least, 22.000 YBP. The weasel, G. cuja, is currently reported much further south than the record presented here. This may suggest that the environment around the cave was relatively drier during the LGM, with more open vegetation, and more moderate temperatures than the current Brazilian Cerrado.

  9. Late Pleistocene carnivores (Carnivora: Mammalia from a cave sedimentary deposit in northern Brazil

    Directory of Open Access Journals (Sweden)



    Full Text Available The Brazilian Quaternary terrestrial Carnivora are represented by the following families: Canidae, Felidae, Ursidae, Procyonidae Mephitidae and Mustelidae. Their recent evolutionary history in South America is associated with the uplift of the Panamanian Isthmus, and which enabled the Great American Biotic Interchange (GABI. Here we present new fossil records of Carnivora found in a cave in Aurora do Tocantins, Tocantins, northern Brazil. A stratigraphical controlled collection in the sedimentary deposit of the studied cave revealed a fossiliferous level where the following Carnivora taxa were present: Panthera onca, Leopardus sp., Galictis cuja, Procyon cancrivorus, Nasua nasua and Arctotherium wingei. Dating by Electron Spinning Resonance indicates that this assemblage was deposited during the Last Glacial Maximum (LGM, at least, 22.000 YBP. The weasel, G. cuja, is currently reported much further south than the record presented here. This may suggest that the environment around the cave was relatively drier during the LGM, with more open vegetation, and more moderate temperatures than the current Brazilian Cerrado.

  10. Regional hydrogeology of the Silurian and Ordovician sedimentary rock underlying Niagara Falls, Ontario, Canada (United States)

    Novakowski, Kentner S.; Lapcevic, Patricia A.


    Due to concern over the potential for widespread groundwater contamination in the sedimentary rock underlying the Niagara Falls area, this study was done to investigate the hydrogeology of the Silurian and Ordovician stratigraphy underlying the Upper Niagara River and the Eastern Niagara Peninsula. Seven boreholes (up to 150 m deep) were drilled, instrumented with multiple packer casing, tested for permeability, sampled for inorganic and organic solutes and monitored for hydraulic head to provide data for a conceptual model of regional groundwater flow. Results show that there are at least three distinct groundwater flow regimes in the bedrock. The uppermost regime consists of fracture zones in the Guelph and Lockport Formations, within which hydraulic conductivity, hydraulic head measurements and geochemical analyses indicate active groundwater circulation primarily discharging towards the Niagara Gorge and Escarpment. Underlying the Lockport Formation are an overpressured (high hydraulic head) regime in the Clinton-Upper Cataract-Lower Queenston Formation and an underpressured (low hydraulic head) regime in the Lower Cataract-Upper Queenston Formation. In both regimes, geochemical analyses and permeability measurements indicate very old and saline groundwater which probably has undergone minimal migration since pre-Pleistocene time. The implication based on the study so far, is that potential groundwater contamination below the bottom of the Lockport Formation is probably not significant in the Niagara Falls area except adjacent to the Niagara Gorge where vertical permeability in the lower flow regimes may be enhanced.

  11. Geomorphological and sedimentary evidence of probable glaciation in the Jizerské hory Mountains, Central Europe (United States)

    Engel, Zbyněk; Křížek, Marek; Kasprzak, Marek; Traczyk, Andrzej; Hložek, Martin; Krbcová, Klára


    The Jizerské hory Mountains in the Czech Republic have traditionally been considered to be a highland that lay beyond the limits of Quaternary glaciations. Recent work on cirque-like valley heads in the central part of the range has shown that niche glaciers could form during the Quaternary. Here we report geomorphological and sedimentary evidence for a small glacier in the Pytlácká jáma Hollow that represents one of the most-enclosed valley heads within the range. Shape and size characteristics of this landform indicate that the hollow is a glacial cirque at a degraded stage of development. Boulder accumulations at the downslope side of the hollow probably represent a relic of terminal moraines, and the grain size distribution of clasts together with micromorphology of quartz grains from the hollow indicate the glacial environment of a small glacier. This glacier represents the lowermost located such system in central Europe and provides evidence for the presence of niche or small cirque glaciers probably during pre-Weichselian glacial periods. The glaciation limit (1000 m asl) and paleo-ELA (900 m asl) proposed for the Jizerské hory Mountains implies that central European ranges lower than 1100 m asl were probably glaciated during the Quaternary.

  12. Depositional Environment of Fine-Grained Sedimentary Rocks of the Sinamar Formation, Muara Bungo, Jambi

    Directory of Open Access Journals (Sweden)

    M. Heri Hermiyanto Zajuli


    Full Text Available DOI: 10.17014/ijog.v8i1.153The research area is situated in the northwestern side of South Sumatra Basin, which is a part of Muara Bungo Regency, Jambi Province. The Oligocene Sinamar Formation consists of shale, claystone, mudstone, sandstone, conglomeratic sandstone, and coal-seam intercalations. This research was focused on fine sedimentary rock of Sinamar Formation, such as shale, claystone, and mudstone. Primary data were collected from SNM boreholes which have depths varying from 75 m up to 200 m, and outcrops that were analyzed by organic petrographic method, gas chromatography-mass spectrometry (GC-MS of normal alkanes including isoprenoids, and sterane. The dominant maceral group is exinite, composed of alginite (3.4 - 18%, and resinite (1.6 - 5.6%, while vitrinite maceral consists of tellocolinite 0.4 - 0.6%, desmocollinite 0.4%, and vitrodetrinite 8.4 - 16.6%. Organic petrography and biomarker analyses show that organic materials of shales were derived from high plants and algae especially Botrycoccus species. Botrycoccus and fresh water fish fossil, found in the shale indicate a lacustrine environment.

  13. Organic geochemical characterization of the Lower-Middle Triassic sedimentary rocks from south China (United States)

    Saito, R.


    The most devastated environments and depleted biodiversity on Earth occurred during the Early Triassic epoch following the latest Permian mass extinction. Complete biotic recovery, characterized by a return to pre-extinction diversity levels, took an extraordinarily long time (ca. 5 x 106 yr), probably because harsh conditions developed repeatedly during the Early Triassic. Newly obtained organic geochemistry data from south China area, indicated a variety of biotic (eukaryotic algae, cyanobacteria, bacteria, and archaea) and environmental fluctuations (redox) during the Early Triassic. Remarkably, some sedimentary rocks from Lower Triassic strata contain rare biomarkers such as biphytanes and okenane, whch are biomarkers for archaea and purple sulfur bacteria, respectively. This is the first study to describe in detail primary producers, microbes, and redox conditions in the Early-Early Middle Triassic, on the basis of biomarkers such as steranes, 2-methyl hopanes, hopanes, biphytanes, regular isoprenoids, n-alkanes, okenane, chlorobactane, β-carotane, and γ-carotane. The results greatly not only increase our understanding of the recovery processes that occurred following the Permian mass extinction, but also emphasize an effectiveness of organic geochemistry against the Early Triassic.

  14. Toward a Reduced Complexity Channel Resolving Model for Sedimentary Delta Formation (United States)

    Liang, M.; Voller, V. R.; Edmonds, D. A.; Paola, C.


    Predicting styles of delta growth in restoration areas is a challenge as we try to restore impacted coastlines. Cellular and rule-based reduced complexity models offer a worthwhile means of uncovering key dynamics in delta morphodynamics without the need to fully solve the governing transport equations. In terms of modeling sedimentary delta building processes a critical ingredients is accounting for the formation and bifurcation of channels; phenomena that can be related to the formation of levees and mouth-bars. To that end, we have developed a reduced complexity model that uses a simplified shallow-water solver to study channel formation, mouth bar deposition, and delta development under different forcings. Under the assumption that the flow has a very low Froude Number (Fr2jet. We test the reduced model against flow over Gaussian-shaped bumps of various heights. Comparison of results from this model with results from a full scale commercial code (Delft3D) show a satisfactory agreement on the critical mouth bar height needed to divert flow around the bar. Based on the same diffusive equation, we develop a low-Froude water-routing method for reduced complexity morphodynamics models. The preliminary results show that the method is capable of producing reasonable channel forms and mouth bar formation, and provides a good starting point for development of a channel resolving delta building model.

  15. Sedimentary petrology of oil well rock cores; Petrologia sedimentaria de nucleos de rocas de pozos petroleros

    Energy Technology Data Exchange (ETDEWEB)

    Izquierdo M, Georgina; Paredes S, Adriana [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)


    At the request of PEMEX Exploration and Production (PEP), in the area of Geology of the Gerencia de Geotermia, the necessary methodology has been integrated to carry out the geologic characterization of cores obtained during the oil well drilling. The integrated studies have been of utility for PEMEX, because they provide detailed information on the processes, conditions of deposition and diagenesis that occur in sedimentary rocks. On the other hand, this geologic information contributes to the update of the geologic model of the field in study. [Spanish] A solicitud de PEMEX Exploracion y Produccion (PEP), en el area de Geologia de la Gerencia de Geotermia, se ha integrado la metodologia necesaria para llevar a cabo la caracterizacion geologica de nucleos obtenidos durante la perforacion de pozos petroleros. Los estudios integrados han sido de utilidad para PEMEX, pues proporcionan informacion detallada sobre los procesos, condiciones de depositacion y diagenesis que ocurren en rocas sedimentarias. Por otro lado, esta informacion geologica contribuye a la actualizacion del modelo geologico del campo en estudio.

  16. Atmospheric oxygen regulation at low Proterozoic levels by incomplete oxidative weathering of sedimentary organic carbon (United States)

    Daines, Stuart J.; Mills, Benjamin J. W.; Lenton, Timothy M.


    It is unclear why atmospheric oxygen remained trapped at low levels for more than 1.5 billion years following the Paleoproterozoic Great Oxidation Event. Here, we use models for erosion, weathering and biogeochemical cycling to show that this can be explained by the tectonic recycling of previously accumulated sedimentary organic carbon, combined with the oxygen sensitivity of oxidative weathering. Our results indicate a strong negative feedback regime when atmospheric oxygen concentration is of order pO2∼0.1 PAL (present atmospheric level), but that stability is lost at pO2<0.01 PAL. Within these limits, the carbonate carbon isotope (δ13C) record becomes insensitive to changes in organic carbon burial rate, due to counterbalancing changes in the weathering of isotopically light organic carbon. This can explain the lack of secular trend in the Precambrian δ13C record, and reopens the possibility that increased biological productivity and resultant organic carbon burial drove the Great Oxidation Event. PMID:28148950

  17. The sedimentary record of India-Asia collision: an evaluation of new and existing constraints (United States)

    Najman, Yani; Henderson, Alex; Boudagher-Fadel, Marcelle; Godin, Laurent; Parrish, Randy; Bown, Paul; Garzanti, Eduardo; Horstwood, Matt; Jenks, Dan


    The age and degree of diachroneity of India-Asia collision is critical to construction of models of orogenesis and to understanding the causes of spatial variations in Himalayan evolution along strike. The age of collision is quoted between ~65-34 Ma (Jaeger et al 1989; Aitchison et al 2007) and the degree of dichroneity is considered negligible (Searle et al 1997) to substantial (Rowley 1998). Such discrepancy is, to some extent, the result of the different definitions and methods used to define the collision. Here, we evaluate constraints from the sedimentary record preserved in the suture zone and Tethyan Himalaya where a minimum age to collision has been constrained by determining 1) the timing of cessation of marine facies, 2) first evidence of Asian detritus deposited on the Indian plate and 3) first evidence of mixed Indian-Asian detritus in the sedimentary record. Extensive previous work has been carried out on the Indus molasse of the Indus Suture zone in Ladakh, India. Here, cessation of marine facies is dated at 50.5 Ma (Green et al. 2008), with the underlying Chogdo Formation considered to show first evidence of mixed Indian and Asian provenance, and be the oldest Formation of Asian-derived provenance to lie in sedimentary contact with the underlying Indian plate (Clift et al 2001, 2002), thus constraining collision at >50.5 Ma. However, our new mapping and provenance analyses on these rocks show that there is no unequivocal evidence of Indian-derived material in the Chogdo Formation, nor that the Chogdo Formation lies in sedimentary contact with the underlying Indian plate (Henderson et al., in review). Thus we question the timing of Indian-Asian collision based on these evidences. South of the suture zone in India and Tibet, we carried out similar investigations of the youngest Tethyan strata. In Ladakh, Indian plate passive margin limestones of the Paleocene Dibling Fm are overlain by the youngest marine facies of the region, the marine Kong Fm and

  18. Metallogeny of the Lannigou Sedimentary Rock-hosted Disseminated Gold Deposit in Southwestern Guizhou Province, China

    Institute of Scientific and Technical Information of China (English)

    BAO Zhiwei; Jayanta GUHA


    The Lannigou deposit is a large-sized sedimentary rock-hosted disseminated gold (SRHDG)deposit located in the Youjiang Basin. It is hosted by the Middle Triassic turbidite. Wall rock alterations, including silicification, pyritization, arsenopyritization, carbonatization and argillization,commonly occur along fractures. PGE study demonstrates that either Permian basalts or Triassic ultrabasic intrusives are unlikely to be the main source of gold mineralization. Coupled with the lack of other magmatic activity in the vicinity of the mining area, an amagmatic origin is proposed. Organic matter compositions and GC-MS analysis of the ores and host rocks show that the organics in the ores and the host rocks have a common source; the organic matter in the ores was mainly indigenous. The positive correlation between S2 and Au contents, along with the common occurrence of organic inclusions, suggest involvement of organic matter in the ore-forming process in terms of promoting Au leaching from the source rocks, making colloidal Au migration possible, as well as hydrocarbon reduction of sulphate. Geological and geochemical characteristics of the Lannigou deposit suggest that it was formed through circulation of meteoric water and probably less importantly organic bearing formation water driven by high geothermal gradient caused by late Yanshanian extension, which leached Au from the source bed, and then migrated as Au-bisulfides and colloidal Au, culminating in deposition by reduction-adsorption and surface complexation of gold onto the growth surface of arsenian pyrite.

  19. Assessment of Deep Seated Geothermal Reservoirs in Selected European Sedimentary Environments (United States)

    Ungemach, Pierre; Antics, Miklos


    Europe at large enjoys a variety of sedimentary environments. They most often host dependable geothermal reservoirs thus favouring the farming of hot fluids, within the low to medium enthalpy range, among which geothermal district heating (GDH) and combined heat and power (CHP) undertakings hold a dominant share. Three selected reservoir settings, addressing carbonate and clastic deposits, the Central part of the Paris Basin, the Southern Germany Molasse Basin in the Münich area and the Netherland Basin respectively will be presented and the exploratory, modeling and development strategies discussed accordingly. Whereas 2D (reprocessed) and 3D seismics have become a standard in matching the distinctive (reef facies, an echelon faulting, carbonate platform layering) features of a deep buried karst and a key to drilling success in the Molasse Basin, thus emphasizing a leading exploratory rationale, the Netherland and Paris Basin instead benefit from a mature data base inherited from extensive hydrocarbon exploration campaigns, with concerns focused on reservoir modeling and sustainable management issues. As a result the lessons learned from the foregoing have enabled to build up a nucleus of expertise in the whole chain from resource identification to reservoir assessment and market penetration. The seismic risk, indeed a sensitive though somewhat emotional issue, which is requiring special attention and due microseismic monitoring from the geothermal community will also be commented.

  20. Late Pleistocene carnivores (Carnivora: Mammalia) from a cave sedimentary deposit in northern Brazil. (United States)

    Rodrigues, Shirlley; Avilla, Leonardo S; Soibelzon, Leopoldo H; Bernardes, Camila


    The Brazilian Quaternary terrestrial Carnivora are represented by the following families: Canidae, Felidae, Ursidae, Procyonidae Mephitidae and Mustelidae. Their recent evolutionary history in South America is associated with the uplift of the Panamanian Isthmus, and which enabled the Great American Biotic Interchange (GABI). Here we present new fossil records of Carnivora found in a cave in Aurora do Tocantins, Tocantins, northern Brazil. A stratigraphical controlled collection in the sedimentary deposit of the studied cave revealed a fossiliferous level where the following Carnivora taxa were present: Panthera onca, Leopardus sp., Galictis cuja, Procyon cancrivorus, Nasua nasua and Arctotherium wingei. Dating by Electron Spinning Resonance indicates that this assemblage was deposited during the Last Glacial Maximum (LGM), at least, 22.000 YBP. The weasel, G. cuja, is currently reported much further south than the record presented here. This may suggest that the environment around the cave was relatively drier during the LGM, with more open vegetation, and more moderate temperatures than the current Brazilian Cerrado.

  1. Paleomagnetism of the Upper Carboniferous and Upper Permian sedimentary rocks from Novaya Zemlya Archipelago (United States)

    Abashev, Victor V.; Mikhaltsov, Nikolay E.; Vernikovsky, Valery A.; Metelkin, Dmitry V.; Matushkin, Nikolay Yu.; Doubrovine, Pavel V.


    Here we present the first paleomagnetic directions and paleomagnetic poles for Upper Permian and Upper Carboniferous sedimentary rocks (sandstones and limestones) of the Novaya Zemlya Archipelago in the Russian High Arctic region. The paleomagnetic directions were obtained through detailed thermal and alternating field demagnetization experiments, using the principal component analysis of demagnetization data. A positive fold test and a positive reversal test indicate that the isolated paleomagnetic directions correspond to the primary magnetization components. Magnetic remanence carriers were characterized through rock-magnetic analyses, including measurements of temperature dependence of low-field magnetic susceptibility, magnetic hysteresis curves, and first-order reversal curves (FORC). We will describe the rock-magnetic properties of different lithological units and discuss their implications for the stability of natural remanent magnetization (NRM) and the veracity of paleomagnetic record. The tectonics implications of the new paleomagnetic data for the evolution of the Barents-Kara continental margin and the Novaya Zemlya Archipelago will be also discussed. The paleomagnetic poles differ slightly from the corresponding section of the APWP for Baltica, which is probably due to inclination shallowing effect or the tectonic features of the region. The study was supported by Russian Science Foundation grant 14-37-00030, the SIU project HNPla-2013/10049 (HEAT) and by Ministry of Education and Science of the Russian Federation grant 5.515.2014/K.

  2. Deciphering the lithological consequences of bottom trawling to sedimentary habitats on the shelf (United States)

    Oberle, Ferdinand K. J.; Swarzenski, Peter W.; Reddy, Christopher M.; Nelson, Robert K.; Baasch, Benjamin; Hanebuth, Till J. J.


    Widespread bottom trawling on the NW Iberian shelf causes chronic sediment and habitat disturbance. The few studies that have investigated vessel-modified sedimentary-structure and texture of the seabed have typically classified their results as being either impacted by trawling or not. This study indicates that bottom trawling can result in a sequence of vastly different effects to the lithology of seabed sediment, which have in turn different ecological consequences. Here, we combined very high-resolution spatial bottom-trawling data with sedimentological (grain size, porosity) and geochemical datasets (excess 210Pb, 3D petroleum fingerprinting) to study sediment disturbance, including sorting and mixing. Our results were used to develop five conceptual disturbance scenarios: minimal seabed effects, sediment overturning, complete sediment mixing, sediment grading and layering, and loss of sediment. Considering that bottom trawling is a widespread and growing global fishing technique, such impacts need to be considered in the management of habitat conservation as well as in the reconstruction of late Holocene climate history from shallow-water deposits, not just on the NW Iberian shelf, but also globally.

  3. Changes of scaling relationships in an evolving population: The example of "sedimentary" stylolites (United States)

    Peacock, D. C. P.; Korneva, I.; Nixon, C. W.; Rotevatn, A.


    Bed-parallel (;sedimentary;) stylolites are used as an example of a population that evolves by the addition of new components, their growth and their merger. It is shown that this style of growth controls the changes in the scaling relationships of the population. Stylolites tend to evolve in carbonate rocks through time, for example by compaction during progressive burial. The evolution of a population of stylolites, and their likely effects on porosity, are demonstrated using simple numerical models. Starting with a power-law distribution, the adding of new stylolites, the increase in their amplitudes and their merger decrease the slope of magnitude versus cumulative frequency of the population. The population changes to a non-power-law distribution as smaller stylolites merge to form larger stylolites. The results suggest that other populations can be forward- or backward-modelled, such as fault lengths, which also evolve by the addition of components, their growth and merger. Consideration of the ways in which populations change improves understanding of scaling relationships and vice versa, and would assist in the management of geofluid reservoirs.

  4. The impact of vegetation on sedimentary organic matter composition and PAH desorption

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, Elizabeth Guthrie [North Carolina State University, Department of Forestry and Environmental Resources, 2800 Faucette Drive, Raleigh, NC 27695 (United States)], E-mail:; Gregory, Samuel T.; Musella, Jennifer S. [North Carolina State University, Department of Forestry and Environmental Resources, 2800 Faucette Drive, Raleigh, NC 27695 (United States)


    Relationships between sedimentary organic matter (SOM) composition and PAH desorption behavior were determined for vegetated and non-vegetated refinery distillate waste sediments. Sediments were fractionated into size, density, and humin fractions and analyzed for their organic matter content. Bulk sediment and humin fractions differed more in organic matter composition than size/density fractions. Vegetated humin and bulk sediments contained more polar organic carbon, black carbon, and modern (plant) carbon than non-vegetated sediment fractions. Desorption kinetics of phenanthrene, pyrene, chrysene, and C{sub 3}-phenanthrene/anthracenes from humin and bulk sediments were investigated using Tenax beads and a two-compartment, first-order kinetic model. PAH desorption from distillate waste sediments appeared to be controlled by the slow desorbing fractions of sediment; rate constants were similar to literature values for k{sub slow} and k{sub veryslow}. After several decades of plant colonization and growth (Phragmites australis), vegetated sediment fractions more extensively desorbed PAHs and had faster desorption kinetics than non-vegetated sediment fractions. - Plants alter sediment organic matter composition and PAH desorption behavior.

  5. Veneers, rinds, and fracture fills: Relatively late alteration of sedimentary rocks at Meridiani Planum, Mars (United States)

    Knoll, Andrew H.; Jolliff, Brad L.; Farrand, William H.; Bell, James F., III; Clark, Benton C.; Gellert, Ralf; Golombek, M. P.; Grotzinger, John P.; Herkenhoff, Kenneth E.; Johnson, Jeffrey R.; McLennan, Scott M.; Morris, Richard; Squyres, Steven W.; Sullivan, Robert; Tosca, Nicholas J.; Yen, Albert; Learner, Zoe


    Veneers and thicker rinds that coat outcrop surfaces and partially cemented fracture fills formed perpendicular to bedding document relatively late stage alteration of ancient sedimentary rocks at Meridiani Planum, Mars. The chemistry of submillimeter thick, buff-colored veneers reflects multiple processes at work since the establishment of the current plains surface. Veneer composition is dominated by the mixing of silicate-rich dust and sulfate-rich outcrop surface, but it has also been influenced by mineral precipitation, including NaCl, and possibly by limited physical or chemical weathering of sulfate minerals. Competing processes of chemical alteration (perhaps mediated by thin films of water or water vapor beneath blanketing soils) and sandblasting of exposed outcrop surfaces determine the current distribution of veneers. Dark-toned rinds several millimeters thick reflect more extensive surface alteration but also indicate combined dust admixture, halite precipitation, and possible minor sulfate removal. Cemented fracture fills that are differentially resistant to erosion occur along the margins of linear fracture systems possibly related to impact. These appear to reflect limited groundwater activity along the margins of fractures, cementing mechanically introduced fill derived principally from outcrop rocks. The limited thickness and spatial distribution of these three features suggest that aqueous activity has been rare and transient or has operated at exceedingly low rates during the protracted interval since outcropping Meridiani strata were exposed on the plains surface.

  6. Seasonal and spatial contrasts of sedimentary organic carbon in floodplain lakes of the central Amazon basin. (United States)

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


    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

  7. Neutron Imaging of Rapid Water Imbibition in Fractured Sedimentary Rock Cores (United States)

    Cheng, Chu-Lin; Perfect, Edmund; Donnelly, Brendan; Bilheux, Hassina; Tremsin, Anton; McKay, Larry; Distefano, Victoria; Cai, Jianchao; Santodonato, Lou


    Advances in nondestructive testing methods, such as neutron, nuclear magnetic resonance, and x-ray imaging, have significantly improved experimental capabilities to visualize fracture flow in various important fossil energy contexts, e.g. enhanced oil recovery and shale gas. We present a theoretical framework for predicting the rapid movement of water into air-filled fractures within a porous medium based on early-time capillary dynamics and spreading over rough fracture surfaces. The theory permits estimation of sorptivity values for the matrix and fracture zone, as well as a dispersion parameter which quantifies the extent of spreading of the wetting front. Dynamic neutron imaging of water imbibition in unsaturated fractured Berea sandstone cores was employed to evaluate the proposed model. The experiments were conducted at the Neutron Imaging Prototype Facility at Oak Ridge National Laboratory. Water uptake into both the matrix and fracture zone exhibited square-root-of-time behavior. Both theory and neutron imaging data indicated that fractures significantly increase imbibition in unsaturated sedimentary rock by capillary action and surface spreading on rough fracture faces. Fractures also increased the dispersion of the wetting front.

  8. Measurements of frequency dependent shear wave attenuation in sedimentary basins using induced earthquakes (United States)

    Richter, Tom; Wegler, Ulrich


    Modeling of peak ground velocity caused by induced earthquakes requires detailed knowledge about seismic attenuation properties of the subsurface. Especially shear wave attenuation is important, because shear waves usually show the largest amplitude in high frequency seismograms. We report intrinsic and scattering attenuation coefficients of shear waves near three geothermal reservoirs in Germany for frequencies between 2 Hz and 50 Hz. The geothermal plants are located in the sedimentary basins of the upper Rhine graben (Insheim and Landau) and the Molasse basin (Unterhaching). The method optimizes the fit between Green's functions for the acoustic, isotropic radiative transfer theory and observed energy densities of induced earthquakes. The inversion allows the determination of scattering and intrinsic attenuation, site corrections, and spectral source energies for the investigated frequency bands. We performed the inversion at the three sites for events with a magnitude between 0.7 and 2. We determined a transport mean free path of 70 km for Unterhaching. For Landau and Insheim the transport mean free path depends on frequency. It ranges from 2 km (at 2 Hz) to 30 km (at 40 Hz) for Landau and from 9 km to 50 km for Insheim. The quality factor for intrinsic attenuation is constant for frequencies smaller than 10 Hz at all three sites. It is around 100 for Unterhaching and 200 for Landau and Insheim with higher values above 10 Hz.

  9. Ripple marks as indicators of Late Ordovician sedimentary environments in Northwest Estonia

    Directory of Open Access Journals (Sweden)

    Hints, Linda


    Full Text Available Late Ordovician sedimentary environments promoting the development of ripple marks in shallow shelf carbonate deposits of northern Estonia are analysed. Ripple marks are described using different parameters (wavelength, height, and wave and asymmetry indexes. Rippled bedding is exposed in a large area in the uppermost Keila Stage, on the upper boundary of micritic-peloidal limestones (Pääsküla Member of the Kahula Formation. Beds with ripples are overlain by organodetrital lime­stones (Saue Member of the Kahula Formation transitional to grainstones or mud mounds of the Vasalemma Formation. The content of peloids in the Pääsküla Member is relatively high and their size (0.04–0.06 mm corresponds to the grain size of sediments capable of forming ripple marks. Weakly asymmetrical sinusoidal ripple marks are oriented in a north–south direction and have likely been formed in the shallow-water zone of the shoal at some distance from the shore. The wave-current origin of the studied ripples can be inferred from ripple indexes. Ripples were subjected to some erosion and in the shallowing-upwards conditions a rocky bottom with the Trypanites ichnofacies evolved. The rippled surface terminates a small-scale cycle (parasequence of the depositional sequence.

  10. Sedimentary record of terminal Cretaceous accretions in Ecuador: The Yunguilla Group in the Cuenca area (United States)

    Jaillard, Etienne; Bengtson, Peter; Ordoñez, Martha; Vaca, Wilmer; Dhondt, Annie; Suárez, Johnny; Toro, Jorge


    A reappraisal of the "Late Cretaceous Yunguilla Formation" of the Cuenca area enables the definition of four distinct formations, correlatable with those of southwestern Ecuador. A mid- to late-Campanian marine transgression (Jadán Formation) is overlain by quartz-rich conglomerates of fan-delta to turbiditic fan environment (Quimas Formation) of latest Campanian-earliest Maastrichtian age, which are interpreted as evidence of the accretion of a first oceanic terrane (San Juan). Disconformable, arkosic turbidites and cherts (Tabacay Formation) of early Maastrichtian age are thought to represent the erosion of the newly accreted oceanic terrane. A major unconformity of late Maastrichtian age, caused by the accretion of a second oceanic terrane (Guaranda), is followed by the deposition of quartz-rich micaceous shelf sandstones (Saquisilí Formation) of Paleocene age. A third accretion event (late Paleocene) is recorded in coastal Ecuador. Each accretion event correlates with the uplift and erosion of the Eastern Cordillera and with a sedimentary hiatus in the eastern areas. In Ecuador, accretion of oceanic terranes contributed to the build up of the Andes through tectonic underplating of low-density material, and the eastern areas did not behave as flexural foreland basins during late Cretaceous-Paleogene times.

  11. Kalahari salt pans as sedimentary archives for reconstruction of Quaternary environments (United States)

    Schüller, Irka; Belz, Lukas; Wilkes, Heinz; Wehrmann, Achim


    Environmental changes in southern Africa come along with variations in atmospheric and oceanic circulation as well as anthropogenic caused landuse changes. The reconstruction of the paleoenvironment is complicated by the fact that continuous geoarchives are rare in the semiarid to arid parts of this region. In the south-western Kalahari lacustrine systems with constant sedimentary records are absent due to the low precipitation. Salt pans are common geomorphological structures in the Kalahari which are temporarily flooded during summer season when isolated showers occur in their local catchment area. So, they are potential archives preserving environmental signals in phases of sedimentation. However, marginal dunes on their leeward sides represent phases of deflation. The principle processes in salt pan formation are complex and so far under discussion. Our study follows a multidisciplinary approach integrating sedimentological, geochemical and microbiological methods to understand the formation of salt pans as a prerequisite for using them as geoarchives in reconstruction of the paleoenvironmental condition during phases of sedimentation and erosion. Sediment cores from five salt pans were analysed using XRD, XRF and grain size analyses. Additionally, age models can be given for four salt pans, based on δ14C from bulk sediment TOC. As palynological material is lacking, different methods in organic geochemistry were applied (plant biomarkers, particularly leaf wax n-alkanes and n-alcohols and their stable carbon and hydrogen isotopic signatures) to reconstruct variations in local vegetation assemblages. Our results allow a better understanding of the sedimentology of salt pans and their interpretation as discontinuous archives.

  12. Sedimentary cycles of trace elements in Salawusu River Valley since 150 ka BP

    Institute of Scientific and Technical Information of China (English)


    The paper makes some analyses on 11 trace elements in the Milanggouwan stratigraphical section in the Salawusu River valley, which is regarded as a prototype geology-palaeoclimate record since 150 ka BP. The results show that the content and variation of trace elements has experienced remarkably regular changes in the pace with coarse and fine sedimentary cycles of palaeo-aeolian sands to its overlying fluvio-lacustrine facies or/and palaeosols. The trace elements with chemical properties of relatively active (V, Sr, Cu, Ni, As) and relatively stable (P, Pb, Rb, Mn, Nb, Zr) are a manifestation of the corresponding 27 changeable cycles between peak and valley values, appearing a multi-fluctuational process line of relative gathering and migration since then. The low numerical value distribution of these two types of trace elements in the aeolian sand facies represents erosion and accumulation under wind force during the cold-dry climate. Whereas their enrichments in both fluvio-lacustrine facies and palaeosols are related to the valley's special low-lying physiognomic position between the Ordos Plateau and the Loess Plateau under the warm and humid climate conditions. The above relatively migrated and gathered change of the trace elements is the result of 27 climatic cycles of cold-dry and warm-humid, which is probably caused by repeated alternations of winter monsoon and summer monsoon in the Mu Us Sandy Land influenced by the climate vicissitudes in northern hemisphere during glacial and interglacial periods since 150 ka BP.

  13. Late Miocene sedimentary environments in south-western Amazonia (Solimões Formation; Brazil). (United States)

    Gross, Martin; Piller, Werner E; Ramos, Maria Ines; Douglas da Silva Paz, Jackson


    In Miocene times a vast wetland existed in Western Amazonia. Whereas the general development of this amazing ecosystem is well established, many questions remain open on sedimentary environments, stratigraphical correlations as well as its palaeogeographical configuration. Several outcrops located in a barely studied region around Eirunepé (SW Amazonas state, Brazil) were investigated to obtain basic sedimentological data. The observed deposits belong to the upper part of the Solimões Formation and are biostratigraphically dated to the Late Miocene. Vertically as well as laterally highly variable fine-grained clastic successions were recorded. Based on the lithofacies assemblages, these sediments represent fluvial deposits, possibly of an anastomosing river system. Sand bodies formed within active channels and dominant overbank fines are described (levees, crevasse splays/channels/deltas, abandoned channels, backswamps, floodplain paleosols). Lacustrine environments are restricted to local floodplain ponds/lakes. The mollusc and ostracod content as well as very light δ(18)O and δ(13)C values, measured on ostracod valves, refer to exclusively freshwater conditions. Based on palaeontological and geological results the existence of a long-lived lake ("Lake Pebas") or any influx of marine waters can be excluded for that region during the Late Miocene.

  14. Organotemplate structures in sedimentary manganese carbonates of the Neoproterozoic Penganga Group, Adilabad, India

    Indian Academy of Sciences (India)

    Joydip Mukhopadhyay; Jens Gutzmer; Nicolas J Beukes


    Manganese carbonates interstratified with bedded chert in the Chanda Limestone of the Neoproterozoic Penganga Group at Adilabad, south India, have been studied for possible evidence that microbiota played a role in the mediation of early diagenetic Mn-carbonate formation in Precam- brian marine sedimentary successions. The manganese carbonate and chert beds occur within a below wave base, deep-water distally steepened ramp succession. High resolution SEM petrogra- phy of the manganese carbonates revealed two basic morphologies — spherical to oval-cylindrical shaped microconcretions, and tubular to irregular, elongated, film-like microstructures. Infolded filmy to hollow tubular strand-like internal morphologies of the spherical to oval-cylindrical shaped microconcretions suggest their microbial affinity. The tubular and film morphologies with mesh- like interconnections closely resemble architectures of microbial extracellular polymeric substance (EPS). Mineralization took place on these organotemplates by the process of permineralization as well as replacement in an early diagenetic pore-water environment with reduction of higher manganese oxy-hydroxides by organic matter and consequent increase in dissolved carbonate.

  15. Magmatism in the brazilian sedimentary basins and the petroleum geology; Magmatismo nas bacias sedimentares brasileiras e sua influencia na geologia do petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Thomaz Filho, Antonio; Antonioli, Luzia [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Faculdade de Geologia]. E-mails:;; Mizusaki, Ana Maria Pimentel [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Inst. de Geociencias]. E-mail:


    In the recent years, the researches on the magmatic events that occurred in the Brazilian sedimentary basins had shown the importance of these episodes for the hydrocarbons exploration. The generation (heating), migration (structural and petrographic alterations), accumulation (basalt fractures) and migrations barriers (sills and dykes) of the hydrocarbons, produced for these rocks, are cited in the marginal and intra continental Brazilian basins. The magmatism produce the temperature increase in the sedimentary basin, around its intrusion, and this propitiate the maturation of the organic matter contained in the hydrocarbons generating rocks of the basin. At the same time, has been verified that the contacts dykes/sedimentary rocks can represent important ways for the hydrocarbons migrations. Recent studies have shown that the magmatism, in its extrusive manifestations, can be analyzed in view of the possibility of having acted as effective hydrocarbon seals and, in consequence, making possible the accumulation of hydrocarbons generated in the underlying sediments. The magmatism of predominantly basic to intermediary character is generated in the asthenosphere, that is, below the lithosphere. The dykes that had introduced in the basement of our sedimentary basins are good heat conductors and we can expect the geothermal gradients increase in the overlapped sedimentary deposits. The more detailed study of the magmatic processes in the Brazilian sedimentary basins must lead to new forms of hydrocarbons exploration in our sedimentary basins, also in those basins where the traditional exploration activities have not occasioned the waited expected successes. (author)

  16. Sedimentary uranium deposits in France and French Union; Les gisements uraniferes dans les formations sedimentaires en France et dans l'Union francaise

    Energy Technology Data Exchange (ETDEWEB)

    Kervella, F. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires


    The author gives the actual state of our knowledge on uranium deposits found in recent years. Till now in precambrian formations only one important deposit has been found, at Mounana (Gabon) in a series of conglomeratic sandstones belonging to the 'Francevillien'. The observed mineralization is of the uranium-vanadium type. To the carboniferous formations corresponds in France a series of deposits, among which the most important ones are located at Saint-Hippolyte. Uranium as carburans, organic-bound complexes, is contained in lacustrine schists of Westphalian or lower Stephanian formations. A number of occurrences are also known in permo-triassic formations, particularly in the Vanoise Alps, in the Maritime Alps and in the Herault, where important occurrences have recently been found not far from Lodeve. The cretaceous and tertiary systems contain uranium deposits in phosphate rocks (Morocco, Senegal, Togo, Middle-Congo). Two sedimentary oligocene deposits are known in France. Lastly, the Vinaninkarena deposit in Madagascar, known for a long time, is the only important one reported in the quaternary series. (author) [French] L'auteur fait le point des connaissances acquises sur les gisements decouverts dans les formations sedimentaires en France et dans l'Union francaise au cours des dernieres annees. Les gisements sont classes selon l'age de la formation dans laquelle on les observe. Les terrains precambriens n'ont pour l'instant fourni qu'un seul gisement notable; situe a Mouana (Gabon). C'est en decembre 1956 que cet important gisement fut decouvert dans une serie de gres conglomeratiques appartenant au Francevillien. La mineralisation observee est du type vanadium-uranium. Au carbonifere correspond en France metropolitaine une serie de gisements d'interet variable. Les plus importants sont ceux de Saint-Hippolyte (Haut-Rhin) ou l'uranium est contenu dans des schistes lacustres du Westphalien ou du

  17. Trend prediction of chaotic time series

    Institute of Scientific and Technical Information of China (English)

    Li Aiguo; Zhao Cai; Li Zhanhuai


    To predict the trend of chaotic time series in time series analysis and time series data mining fields, a novel predicting algorithm of chaotic time series trend is presented, and an on-line segmenting algorithm is proposed to convert a time series into a binary string according to ascending or descending trend of each subsequence. The on-line segmenting algorithm is independent of the prior knowledge about time series. The naive Bayesian algorithm is then employed to predict the trend of chaotic time series according to the binary string. The experimental results of three chaotic time series demonstrate that the proposed method predicts the ascending or descending trend of chaotic time series with few error.

  18. Stromatolite branching in the Neoproterozoic of the Centralian Superbasin, Australia: an investigation into sedimentary and microbial control of stromatolite morphology. (United States)

    Planavsky, Noah; Grey, Kathleen


    The extensive and well-preserved Neoproterozoic Acaciella australica Stromatolite assemblage of Australia is ideal for examining the relative roles of microbial and environmental influences on stromatolite branching and stromatolite macrostructure across a wide geographical area. Detailed sedimentological analyses indicate that the basal hemispheroidal section of bioherms contains abundant sediment. By contrast, the columnar sections of bioherms are composed almost exclusively of micritic laminae. These micritic laminae display little evidence for environmental, especially sedimentary, control over stromatolite morphology. The change from a hemispheroidal morphology to branching morphology is linked to variations in the relative contributions of sediment and framework growth. The shift to columns appears to be closely linked to a decrease in sediment supply that resulted in a more stable environment in which microbially mediated framework growth began to control stromatolite morphology. Branching in the A. australica assemblage stromatolites appears to be caused by shifting sedimentary and microbial control on stromatolite morphology.

  19. U-Pb zircon age data for selected sedimentary, metasedimentary, and igneous rocks from northern and central Alaska (United States)

    Moore, Thomas E.


    This publication contains the complete results of U-Pb zircon age dating studies of sedimentary and metasedimentary units from northern and central Alaska that are discussed and interpreted in other reports by the author. Most of the U-Pb ages are of detrital zircons from sandstones, although U-Pb ages from igneous and sedimentary clasts from conglomerates in some of those same units are also included. In addition to the data presented in the interpretive reports, this publication includes data that were excluded due to discordance, analytical problems, and publication space limitations. The U-Pb age data are reported in Excel-file format so that they can be easily downloaded and referenced or reinterpreted by future workers.

  20. Linking the Fe-, Mo-, and Cr isotope records with the multiple S isotope record of Archean sedimentary rocks (United States)

    Ohmoto, H.; Watanabe, Y.


    Researchers have interpreted the isotopic data of redox sensitive elements (e.g., Fe, Mo and Cr) in Archean- and Proterozoic-aged sedimentary rocks within a framework of an atmospheric O2 evolution model that relied on an interpretation of the multiple sulfur isotopic record of sedimentary rocks. The current paradigm is that the anomalous isotopic fractionations of sulfur (AIF-S, or MIF-S) in sedimentary rocks were created by the UV photolysis of volcanic SO2 in an O2-poor (i.e., pO2 atmosphere, and that the rise of atmospheric pO2 to > 1 ppm occurred at ~2.45 Ga. However, this paradigm has recently encountered the following serious problems: (1) UV photolysis of SO2 by a broad-band UV lamp, which simulates the UV spectra of the sun light, produced the δ34S-Δ33S values for the S0 and SO4 that are significantly different from >90% of data on natural samples. (2) Many Archean-age sedimentary rocks do not exhibit AIF-S signatures. (3) Strong AIF-S signatures are typically found in organic C- and pyrite rich Archean-age black shales that were altered by submarine hydrothermal fluids during the early diagenetic stage of the rocks. (4) H2S, rather than SO2, was probably the dominant S-bearing volcanic gas on an anoxic Earth. Yet, UV photolysis of H2S does not generate AIF-S. (5) Some post-2.0 Ga natural samples were found to possess strong AIF-S signatures, such as sulfates in air pollutants that were produced by coal burning in an oxygen-rich atmosphere. Lasaga et al. (2008) demonstrated theoretically that chemisorption reactions between some solid surfaces and S-bearing aqueous (or gaseous) species, such as between organic matter and aqueous sulfate, may generate AIF-S. Watanabe et al. (2009; in prep.) demonstrated experimentally that reactions between simple amino acid crystals and sulfate under hydrothermal conditions produced AIF-S signatures that matched with more than 90% of data on natural samples. These studies, as well as the observed correlations between the

  1. Development and application of sedimentary pigments for assessing effects of climatic and environmental changes on subarctic lakes in northern Sweden

    DEFF Research Database (Denmark)

    Reuss, Nina Steenberg; Leavitt, Peter R.; Hall, Roland I.;


    vegetation zones (alpine, birch, conifer/birch) were incompletely distinguished by the ordinations. In the RDAs, the primary pigment variability occurred along a production gradient that was correlated negatively to water-column DOC content and d13C signature of sediments. This pattern suggested......A surface-sediment survey of pigments in 100 lakes in the Scandes Mountains, northern Sweden, was combined with a reconstruction of Holocene sedimentary pigments from Lake Seukokjaure to assess the major factors regulating phototrophic communities, and how these controls may have changed during...... to the modern tree line. The spatial survey of sedimentary pigments was analyzed using principle components analysis (PCA) and redundancy analysis (RDA). PCA explained 73-83% of variance in pigment abundance and composition, whereas RDA explained 22-32% of variation in fossil assemblages. Dissolved organic...

  2. Sedimentary records of black carbon in the sea area of the Nansha Islands since the last glaciation

    Institute of Scientific and Technical Information of China (English)


    Core 17962 taken from the sea area of the Nansha Islands recorded a sedimentary history of more than 30 000 years. The black carbon data from the core, which can inform us of the history of vegetation fires, show that during the last glaciation, especially during the last glacial maximum at about 18 kaBP, the fluctuation of the concentration and accumulation rate of the black carbon was relatively great, whereas it was small during the Holocene. The isotope composition of the black carbon indicates that the precursors of black carbon were mainly grasses from the last glaciation to the Holocene. The sub-alpine and alpine vegetation zones covered mainly with grass and bush on the lands around the southern South China Sea were probably the sources of black carbon. The altitudinal vegetation changes from the last glaciation to the Holocene gave rise to the changes of the sedimentary characteristics of black carbon.

  3. Geoconservation evaluation of the sites of Miocene sedimentary rocks in the quarries of north-eastern Slovenia

    Directory of Open Access Journals (Sweden)

    Mojca Planjšek


    Full Text Available The article deals with the sites of Miocene sedimentary rocks in north-eastern Slovenia. Due to dense vegetation cover and consequently rare rock outcrops mostly abandoned quarries were elaborated. According to evaluation criteria defined by Nature Conservation Act and Decree on the categories of valuable natural features, out of 28 examined locations 6 were selected as important from the nature conservation point of view. These sites contain mainly the fossilferous lithothamnian limestone and they are proposed to be listed as valuable geological natural features. The quarries Osek – oolite limestone and sandstone site and Zgornji Duplek 1 –lithothamnian limestone siteare proposed as geological natural values of national importance. The lithothamnian rocks used to be importantbuilding stone. Nowadays we find it in some of important cultural monuments like castles, churches and other cultural monuments. In this respect some of the sites of Miocene sedimentary rocks have significant cultural value as well.

  4. Sedimentary pigments and nature of organic matter within the oxygen minimum zone (OMZ) of the Eastern Arabian Sea (Indian margin)

    Digital Repository Service at National Institute of Oceanography (India)

    Rasiq, K.T.; Kurian, S.; Karapurkar, S.G.; Naqvi, S.W

    Research Part A. Oceanographic Research Papers, 38, 969-984. Reuss, N., Leavitt, P.R., Hall, R.I., Bigler, C. and Hammarlund, D., 2010. Development and application of sedimentary pigments for assessing effects of climatic and environmental changes..., India supported this work. This is NIO contribution No: References Agnihotri, R., Kurian, S., Fernandes, M., Reshma, K., D'Souza, W. and Naqvi, S.W.A., 2008. Variability of subsurface denitrification and surface productivity in the coastal eastern...

  5. Biogenicity and Syngeneity of Organic Matter in Ancient Sedimentary Rocks: Recent Advances in the Search for Evidence of Past Life


    Dorothy Z. Oehler; Cady, Sherry L.


    The past decade has seen an explosion of new technologies for assessment of biogenicity and syngeneity of carbonaceous material within sedimentary rocks. Advances have been made in techniques for analysis of in situ organic matter as well as for extracted bulk samples of soluble and insoluble (kerogen) organic fractions. The in situ techniques allow analysis of micrometer-to-sub-micrometer-scale organic residues within their host rocks and include Raman and fluorescence spectroscopy/imagery...

  6. Sedimentary facies of the central part of radial tidal sand ridge system of the eastern China coast

    Institute of Scientific and Technical Information of China (English)

    Yong YIN; Xinqin ZOU; Dakui ZHU; Jiaxiang HUANG


    A unique radial tidal sand ridge system (RTSRS) has developed under a complex tidal current field on the eastern China coast between the Yangtze River delta to the south and the abandoned Yellow River (Huanghe) delta to the north. The present study examines the sedimentary evolution of a ridge-channel pair in the central RTSRS. Three cores, with two on the ridges and one in the channel, were drilled to reveal the late Pleistocene-Holocene deposits of the system. Five sedimentary facies were distinguished, i.e. ridge-shallow subtidal facies, ridge-deep subtidal facies, near-surface channel bottom facies, middle tidal flat facies and low tidal flat facies. The ridge-shallow subtidal facies consists of sandy strata with ripple cross bed-dings, horizontal lamina, and massive beddings. Bioturbation seldom occurs. The ridge-deep subtidal facies is primarily characterized by sandy and muddy interlayers with common flaser and lenticular bedding structures. Bioturbation appears abundantly. Massive and graded sediment sequences of storm origin are pre-sent as characterized by rich shell fragments. The near-surface channel bottom facies consists of loose, soft, clayey silt deposits with deformed sedimentary layers. This facies occurs in the deeper part of the active chan-nels. The middle tidal flat and lower tidal flat facies composed of silt-clay couplets prevailed primarily in the tidal flats. Incomplete sedimentary successions show that coastal plain deposits dominate in the study area during 12-13 ka B.P. The sandy ridge and channel facies became dominant during 4 6 ka B.P. when the sea level receded temporarily. Tidal ridge and channel in the study area became active during the last four decades. Sediment reworking due to typhoon and sandy ridge migration plays a key role in shaping the present radial ridge system.

  7. Drainage evolution of the Heihe River in western Hexi Corridor, China, derived from sedimentary and magnetostratigraphic results (United States)

    Pan, Baotian; Chen, Dianbao; Hu, Xiaofei; Cao, Xilin; Chen, Jinjun; Mao, Junwei


    The uplifting of the Tibetan Plateau has significantly changed the environment in surrounding areas by delivering abundant water and sediment. The Heihe River draining the Qilian Shan in the NE Tibetan Plateau acts as a dominant sediment routing system from the uplifted NE Tibetan Plateau to the Hexi Corridor as well as the Badain Jaran Desert. Reconstructing the evolution of the Heihe River could provide evidence for the birth of the Badain Jaran Desert and enhance the understanding of sedimentary basin fill and the relationship between tectonism, drainage evolution and environmental changes. With this aim, two parallel cores (DWJ and XKJD with depths of 140 and 68.2 m, respectively) were drilled in the floodplain of the Heihe River. The facies analysis of the sedimentary sequences from the drilling cores showed that the sedimentary environment changed from the lake system to a delta system and finally to a fluvial system at the depths of ∼133.3 and ∼68 m, respectively. The magnetostratigraphic results revealed ages of approximately 1.75 and 1.12 Ma for the DWJ and XKJD cores, respectively, and an age of approximately 1.1 Ma for the transition from delta to fluvial environment in both the cores. The change of the sedimentary environment at approximately 1.1 Ma was caused by the formation of the integrated Heihe River. The integrated Heihe River may have developed via mechanisms such as river capture and river diversion due to the uplifting of the North Qilian Shan and the Longshou Shan. The present study suggested that the formation of large inland rivers, such as the Heihe River and the Shiyang River in NW China, played an important role in the evolution of the deserts and the Loess Plateau.

  8. The late Neoproterozoic to early Cambrian sulphur cycle: an isotopic investigation of sedimentary rocks from the Yangtze platform (United States)

    Goldberg, T.; Strauss, H.


    The sulphur cycle responds to changes in seawater chemistry, biological evolution and tectonic activity. We follow an isotopic approach in order to constrain the state of the ocean/atmosphere system during the late Neoproterozoic and early Cambrian. For this purpose, sedimentary successions from the Yangtze platform, South China, were analysed for their sulphur isotopic composition in different S-bearing phases. The general stratigraphy comprises in ascending order the Doushantuo, Dengying and Niutitang formations. Main lithologies include carbonates, phosphorites, black shales and cherts. The sulphur isotopic composition of the late Neoproterozoic to early Cambrian seawater sulphate ranges from +30 to +35 ‰ as evident from calcium sulphates and trace sulphate in unaltered carbonates and phosphorites (Shields et al., 1999). Sulphur isotopes in chromium reducible and organically bound sulphur are displaced by about +40 ‰ from the seawater sulphate signal, indicating bacterial sulphate reduction. Isotope values range between -16 and +25 ‰ reflecting different environmental conditions, varying from open to closed/limiting conditions in respect to sulphate availability. Pyrite morphology is studied in order to characterize the diagenetic environment. Consistent with a biological origin for the sedimentary pyrite in the Neoproterozoic as well as in the Cambrian (Strauss, 2002) is the positive correlation between sulphide sulphur and organic carbon abundances. The availability of reactive iron is evaluated by means of the degree of pyritization (Raiswell et al., 1988). Raiswell, R. Buckley, F., Berner, R. &Anderson, T. (1988) Degree of pyritization of iron as a paleoenvironmental indicator of bottom-water oxygenation. Journal of Sedimentary Petrology, 58, No.5, 812-819 Shields, G., Strauss, H., Howe, S. &Siegmund, H. (1999) Sulphur isotope composition of sedimentary phosphorites from the basal Cambrian of China: implications for Neoproterozoic-Cambrian biochemical

  9. Structural and Deformation Analysis of Clasts in the Sedimentary Units of the Camarinha Formation, Paraná State

    Directory of Open Access Journals (Sweden)

    Benjamim Bley de Brito Neves


    Full Text Available Sedimentary units of Camarinha Formation (Paraná State, Southern Brazil are affected by the Lancinha TranscurrentShear Zone, and show brittle and brittle-ductile features such as folds, fractures, tilted and truncated layers, cataclasticfoliation, fracture cleavage, and stretched clasts. Analysis of these features revealed their compatibility with theRiedel Model and confi rms the right-lateral movement of the Lancinha Fault. Low values of the X-axis plunge are typicalof transcurrent zones.

  10. Mineralogical correlation of surficial sediment from area drainages with selected sedimentary interbeds at the Idaho National Engineering Laboratory, Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Bartholomay, R.C.


    Ongoing research by the US Geological Survey at the INEL involves investigation of the migration of radioactive elements contained in low-level radioactive waste, hydrologic and geologic factors affecting waste movement, and geochemical factors that influence the chemical composition of the waste. Identification of the mineralogy of the Snake River Plain is needed to aid in the study of the hydrology and geochemistry of subsurface waste disposal. The US Geological Surveys project office at the Idaho National Engineering Laboratory, in cooperation with the US Department of Energy, used mineralogical data to correlate surficial sediment samples from the Big Lost River, Little Lost River, and Birch Greek drainages with selected sedimentary interbed core samples taken from test holes at the RWMC (Radioactive Waste Management Complex), TRA (Test Reactors Area), ICPP (Idaho Chemical Processing Plant), and TAN (Test Area North). Correlating the mineralogy of a particular present-day drainage area with a particular sedimentary interbed provides information on historical source of sediment for interbeds in and near the INEL. Mineralogical data indicate that surficial sediment samples from the Big Lost River drainage contained a larger amount of feldspar and pyroxene and a smaller amount of calcite and dolomite than samples from the Little Lost River and Birch Creek drainages. Mineralogical data from sedimentary interbeds at the RWMC, TRA, and ICPP correlate with surficial sediment of the present-day big Lost River drainage. Mineralogical data from a sedimentary interbed at TAN correlate with surficial sediment of the present-day Birch Creek drainage. 13 refs., 5 figs., 3 tabs.

  11. Mass movement in the eastern margin of the cenozoic Niigata sedimentary basin, central Japan : its geohistorical backgrounds


    Takahama, Nobuyuki


    The geohistorical investigation has been made on the two different kinds of large-scale mass movements in the eastern marginal region of the Niigata Sedimentary basin, i.e., the Gozu debris flows and the Aburuma-gawa landslides. The stratigraphic successions of these mass movement deposits show the following important characteristics common to the both. 1) These mass movements have occurred repeatedly at nearly the same sites since the Middle Pleistocene to the present. 2) During Middle Pleis...

  12. Evolution of deepwater sedimentary environments and its implication for hydrocarbon exploration in Qiongdongnan Basin, northwestern South China Sea

    Institute of Scientific and Technical Information of China (English)

    WANG Zhenfeng; JIANG Tao; ZHANG Daojun; WANG Yahui; ZUO Qianmei; HE Weijun


    Over the past several years, a number of hydrocarbon reservoirs have been discovered in the deepwater area of Qiongdongnan Basin, northwestern South China Sea. These oil/gas fields demonstrate that the evolution of the deepwater sedimentary environment are controlling the formation and distribution of large-scale clastic reservoirs. Integration between seismic and borehole data were necessary to best clarify the distribution and quality of these deepwater reservoirs. Geochemical and paleobiological evidence from discrete samples was also applied to document specific information regarding the sedimentary environment. Results show that the Qiongdongnan Basin has existed as a thriving marine environment since Oligocene, when several rifting depressions developed throughout the entire Qiongdongnan Basin. Triggered by the faults activities, several distinct provenances supplied the coarse sediments, transporting and depositing them in deep parts of the rifting depressions. A fan delta system then formed nearby the source in the deeper area of these rifting depressions. The sedimentary environment of Qiongdongnan gradiationally became deepwater since early Miocene. Consequently, abundances of sediments were transported from Hainan Island and Southern Uplift, and then sunk into the basin center. The submarine fans revealed by many boreholes in this area verified them as good reservoir. Because the area reached its lowest sea level at late Miocene and the Southern Uplift subsidenced under sea level, not providing any sediment, so that the carbonate mesa and biorhythms characteristic of this area also developed during this period. In the west part of Qiongdongnan Basin, sediments transported from Vietnam increased in response to the Tibetan Uplift. Consequently, a central canyon developed along the center of Qiongdongnan Basin, which has been confirmed by several boreholes as a favorable hydrocarbon reservoir. The clarification of the deepwater sedimentary environment

  13. Volcano-sedimentary processes operating on a marginal continental arc: the Archean Raquette Lake Formation, Slave Province, Canada (United States)

    Mueller, W. U.; Corcoran, P. L.


    The 200-m thick, volcano-sedimentary Raquette Lake Formation, located in the south-central Archean Slave Province, represents a remnant arc segment floored by continental crust. The formation overlies the gneissic Sleepy Dragon Complex unconformably, is laterally interstratified with subaqueous mafic basalts of the Cameron River volcanic belt, and is considered the proximal equivalent of the turbidite-dominated Burwash Formation. A continuum of events associated with volcanism and sedimentation, and controlled by extensional tectonics, is advocated. A complex stratigraphy with three volcanic and three sedimentary lithofacies constitute the volcano-sedimentary succession. The volcanic lithofacies include: (1) a mafic volcanic lithofacies composed of subaqueous pillow-pillow breccia, and subaerial massive to blocky flows, (2) a felsic volcanic lithofacies representing felsic flows that were deposited in a subaerial environment, and (3) a felsic volcanic sandstone lithofacies interpreted as shallow-water, wave- and storm-reworked pyroclastic debris derived from explosive eruptions. The sedimentary lithofacies are represented by: (1) a conglomerate-sandstone lithofacies consistent with unconfined debris flow, hyperconcentrated flood flow and talus scree deposits, as well as minor high-energy stream flow conglomerates that formed coalescing, steep-sloped, coarse-clastic fan deltas, (2) a sandstone lithofacies, interpreted as hyperconcentrated flood flow deposits that accumulated at the subaerial-subaqueous interface, and (3) a mudstone lithofacies consistent with suspension sedimentation in a small restricted lagoon-type setting. The Raquette Lake Formation is interpreted as a fringing continental arc that displays both high-energy clastic sedimentation and contemporaneous effusive and explosive mafic and felsic volcanism. Modern analogues that develop along active plate margins in which continental crust plays a significant role include Japan and the Baja California

  14. Sedimentary architecture of the Bohai Sea China over the last 1 Ma and implications for sea-level changes (United States)

    Shi, Xuefa; Yao, Zhengquan; Liu, Qingsong; Larrasoaña, Juan Cruz; Bai, Yazhi; Liu, Yanguang; Liu, Jihua; Cao, Peng; Li, Xiaoyan; Qiao, Shuqing; Wang, Kunshan; Fang, Xisheng; Xu, Taoyu


    Sedimentary architecture dominated by transgression-regression cycles in the shallow Bohai shelf region contains information about global sea-level, climate and local tectonics. However, previous studies of transgression-regression cycles in this region at orbital timescales that extend back to the early Pleistocene are sparse, mainly because of the shortage of well-dated long cores. Although transgression-regression sedimentary cycles in the region have been interpreted in terms of local tectonics, sea-level, and climate change, the detailed structure of marine transgressions and their significance for Quaternary global sea-level variations remains to be examined. In this study, we present an integrated sedimentological, geochemical and paleontological study of a 212.4 m (∼1 Ma) core (BH08) recovered from the Bohai Sea, China, for which an astronomically-based age model is available. Correspondence between marine-terrestrial sedimentary cycles and global sea-level fluctuations suggests that stacking of marine and terrestrial sediments was driven mainly by glacio-eustatic sea-level fluctuations in a context in which tectonic subsidence was largely balanced by sediment supply over the last ∼1 Ma. We report a dominant 100-kyr cycle beginning at ∼650 ka, which reflects the worldwide influence of the mid-Pleistocene transition (MPT) in sea-level records. We find that neritic deposits after the MPT were relatively thicker than before the MPT, which indicates an important control of the MPT on sedimentary architecture through lengthening of the duration of sea-level highstands.

  15. Numerical Sequence of Borane Series

    Directory of Open Access Journals (Sweden)

    Enos Masheija Kiremire


    Full Text Available A table of hydroborane families has been created. The table links boranes of different families(homologous series and members of the same family based on k number. The table is useful deducing straight away whether a borane( molecular formula is closo, nido or arachno or something else. The table also indicates that boranes are formed according to natural periodic function (arithmetical progression. The empirical formula utilized is extremely versatile, simple and based on the principle of Nobel gas configuration. It could be used in both simple and complex boranes and carboranes. The closo members which portray characteristic shapes also have characteristic k1 numbers.

  16. A Course in Time Series Analysis

    CERN Document Server

    Peña, Daniel; Tsay, Ruey S


    New statistical methods and future directions of research in time series A Course in Time Series Analysis demonstrates how to build time series models for univariate and multivariate time series data. It brings together material previously available only in the professional literature and presents a unified view of the most advanced procedures available for time series model building. The authors begin with basic concepts in univariate time series, providing an up-to-date presentation of ARIMA models, including the Kalman filter, outlier analysis, automatic methods for building ARIMA models, a

  17. Trend prediction of chaotic time series

    Institute of Scientific and Technical Information of China (English)


    Trend prediction of chaotic ti me series is anin-teresting probleminti me series analysis andti me se-ries data mining(TSDM)fields[1].TSDM-basedmethods can successfully characterize and predictcomplex,irregular,and chaotic ti me series.Somemethods have been proposed to predict the trend ofchaotic ti me series.In our knowledge,these meth-ods can be classified into t wo categories as follows.The first category is based on the embeddedspace[2-3],where rawti me series data is mapped to areconstructed phase spac...

  18. Sedimentary response to sea ice and atmospheric variability over the instrumental period off Adélie Land, East Antarctica (United States)

    Campagne, Philippine; Crosta, Xavier; Schmidt, Sabine; Noëlle Houssais, Marie; Ther, Olivier; Massé, Guillaume


    Diatoms account for a large proportion of primary productivity in Antarctic coastal and continental shelf zones. Diatoms, which have been used for a long time to infer past sea surface conditions in the Southern Ocean, have recently been associated with diatom-specific biomarkers (highly branched isoprenoids, HBI). Our study is one of the few sedimentary research projects on diatom ecology and associated biomarkers in the Antarctic seasonal sea ice zone. To date, the Adélie Land region has received little attention, despite evidence for the presence of high accumulation of laminated sediment, allowing for finer climate reconstructions and sedimentary process studies. Here we provide a sequence of seasonally to annually laminated diatomaceous sediment from a 72.5 cm interface core retrieved on the continental shelf off Adélie Land, covering the 1970-2010 CE period. Investigations through statistical analyses of diatom communities, diatom-specific biomarkers and major element abundances document the relationships between these proxies at an unprecedented resolution. Additionally, comparison of sedimentary records to meteorological data monitored by automatic weather station and satellite derived sea ice concentrations help to refine the relationships between our proxies and environmental conditions over the last decades. Our results suggest a coupled interaction of the atmospheric and sea surface variability on sea ice seasonality, which acts as the proximal forcing of siliceous productivity at that scale.

  19. Sedimentary Facies Controls on the Upscaling of Petrophysical Properties from Core to Log Scales and Its Implications to Petroleum Exploration

    Institute of Scientific and Technical Information of China (English)

    LiuKeyu; BrettTopham; LincolnPaterson; PeterEadington; PangXiongqi


    The clastic sedimentary realm comprises a number of genetically distinct depositional systems, which are dominated by distinct depositional processes. A variogram and a Levy-stable probability distribution-based geostatistical method have been applied to analyze petrophysical properties from well logs and cores from a variety of depositional environments in sedimentary basins from Australia to quantify the heterogeneity and upscaling range of different depositional systems. Two reservoir sequences with contrasting sedimentary facies, depositional processes and a diagenetic history are investigated for their petrographic, petrophysical and log characters and their scaling behaviour. The microscopic derived petrophysical parameters, including visual porosity, grain size, sorting and amount of matrix, core plug measured porosity and permeability an