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Sample records for upper jurassic shales

  1. Thermal maturity and petroleum kitchen areas of Liassic Black Shales (Lower Jurassic) in the central Upper Rhine Graben, Germany

    Science.gov (United States)

    Böcker, Johannes; Littke, Ralf

    2016-03-01

    In the central Upper Rhine Graben (URG), several major oil fields have been sourced by Liassic Black Shales. In particular, the Posidonia Shale (Lias ɛ, Lower Toarcian) acts as excellent and most prominent source rock in the central URG. This study is the first comprehensive synthesis of Liassic maturity data in the URG area and SW Germany. The thermal maturity of the Liassic Black Shales has been analysed by vitrinite reflectance (VRr) measurements, which have been verified with T max and spore coloration index (SCI) data. In outcrops and shallow wells (oil window (ca. 0.50-0.60 % VRr). This maturity is found in Liassic outcrops and shallow wells in the entire URG area and surrounding Swabian Jura Mountains. Maximum temperatures of the Posidonia Shale before graben formation are in the order of 80-90 °C. These values were likely reached during Late Cretaceous times due to significant Upper Jurassic and minor Cretaceous deposition and influenced by higher heat flows of the beginning rift event at about 70 Ma. In this regard, the consistent regional maturity data (VRr, T max, SCI) of 0.5-0.6 % VRr for the Posidonia Shale close to surface suggest a major burial-controlled maturation before graben formation. These consistent maturity data for Liassic outcrops and shallow wells imply no significant oil generation and expulsion from the Posidonia Shale before formation of the URG. A detailed VRr map has been created using VRr values of 31 wells and outcrops with a structure map of the Posidonia Shale as reference map for a depth-dependent gridding operation. Highest maturity levels occur in the area of the Rastatt Trough (ca. 1.5 % VRr) and along the graben axis with partly very high VRr gradients (e.g. well Scheibenhardt 2). In these deep graben areas, the maximum temperatures which were reached during upper Oligocene to Miocene times greatly exceed those during the Cretaceous.

  2. Inter-layered clay stacks in Jurassic shales

    Science.gov (United States)

    Pye, K.; Krinsley, D. H.

    1983-01-01

    Scanning electron microscopy in the backscattered electron mode is used together with energy-dispersive X-ray microanalysis to show that Lower Jurassic shales from the North Sea Basin contain large numbers of clay mineral stacks up to 150 microns in size. Polished shale sections are examined to determine the size, shape orientation, textural relationships, and internal compositional variations of the clays. Preliminary evidence that the clay stacks are authigenic, and may have formed at shallow burial depths during early diagenesis, is presented.

  3. Fluid flow from matrix to fractures in Early Jurassic shales

    NARCIS (Netherlands)

    Houben, M.E.; Hardebol, N.J.; Barnhoorn, A.; Boersma, Quinten; Carone, A.; Liu, Y.; de Winter, D.A.M.; Peach, C.J.; Drury, M.R.

    2017-01-01

    The potential of shale reservoirs for gas extraction is largely determined by the permeability of the rock. Typical pore diameters in shales range from the μm down to the nm scale. The permeability of shale reservoirs is a function of the interconnectivity between the pore space and the natural

  4. Fluid flow from matrix to fractures in Early Jurassic shales

    NARCIS (Netherlands)

    Houben, M. E.; Hardebol, N.J.; Barnhoorn, A.; Boersma, Q.D.; Carone, A.; Liu, Y.; de Winter, D. A.M.; Peach, C. J.; Drury, M. R.

    2017-01-01

    The potential of shale reservoirs for gas extraction is largely determined by the permeability of the rock. Typical pore diameters in shales range from the μm down to the nm scale. The permeability of shale reservoirs is a function of the interconnectivity between the pore space and the natural

  5. The Jurassic of Denmark and Greenland: The Upper Jurassic of Europe: its subdivision and correlation

    Directory of Open Access Journals (Sweden)

    Zeiss, Arnold

    2003-10-01

    Full Text Available In the last 40 years, the stratigraphy of the Upper Jurassic of Europe has received much attention and considerable revision; much of the impetus behind this endeavour has stemmed from the work of the International Subcommission on Jurassic Stratigraphy. The Upper Jurassic Series consists of three stages, the Oxfordian, Kimmeridgian and Tithonian which are further subdivided into substages, zones and subzones, primarily on the basis of ammonites. Regional variations between the Mediterranean, Submediterranean and Subboreal provinces are discussed and correlation possibilities indicated. The durations of the Oxfordian, Kimmeridgian and Tithonian Stages are reported to have been 5.3, 3.4 and 6.5 Ma, respectively. This review of the present status of Upper Jurassic stratigraphy aids identification of a number of problems of subdivision and definition of Upper Jurassic stages; in particular these include correlation of the base of the Kimmeridgian and the top of the Tithonian between Submediterranean and Subboreal Europe. Although still primarily based on ammonite stratigraphy, subdivision of the Upper Jurassic is increasingly being refined by the incorporation of other fossil groups; these include both megafossils, such as aptychi, belemnites, bivalves, gastropods, brachiopods, echinoderms, corals, sponges and vertebrates, and microfossils such as foraminifera, radiolaria, ciliata, ostracodes, dinoflagellates, calcareous nannofossils, charophyaceae, dasycladaceae, spores and pollen. Important future developments will depend on the detailed integration of these disparate biostratigraphic data and their precise combination with the abundant new data from sequence stratigraphy, utilising the high degree of stratigraphic resolution offered by certain groups of fossils. This article also contains some notes on the recent results of magnetostratigraphy and sequence chronostratigraphy.

  6. Permeability, compressibility and porosity of Jurassic shale from the Norwegian-Danish Basin

    DEFF Research Database (Denmark)

    Mbia, Ernest Ncha; Fabricius, Ida Lykke; Krogsbøll, Anette

    2014-01-01

    The Fjerritslev Formation in the Norwegian-Danish Basin forms the main seal to Upper Triassic-Lower Jurassic sandstone reservoirs. In order to estimate the sealing potential and rock properties, samples from the deep wells Vedsted-1 in Jylland, and Stenlille-2 and Stenlille-5 on Sjael-land, were ...

  7. The Lower Jurassic Posidonia Shale in southern Germany: results of a shale gas analogue study

    Science.gov (United States)

    Biermann, Steffen; Schulz, Hans-Martin; Horsfield, Brian

    2013-04-01

    The shale gas potential of Germany was recently assessed by the Federal Institute for Geosciences and Natural Resources (2012 NiKo-Project) and is - in respect of the general natural gas occurrence in Germany - regarded as a good alternative hydrocarbon source. The Posidonia Shale in northern and southern Germany is one of the evaluated rock formation and easily accessible in outcrops in the Swabian Alps (southern Germany). The area of interest in this work is located in such an outcrop that is actively used for open pit mining next to the town of Dotternhausen, 70 km southwest of Stuttgart. 31 samples from the quarry of Dotternhausen were analyzed in order to characterize the immature Posidonia Shale (Lower Toarcian, Lias ɛ) of southern Germany as a gas shale precursor. Methods included are Rock Eval, Open Pyrolysis GC, SEM, Mercury Intrusion Porosimetry, XRD, and other. The samples of Dotternhausen contain exclusively type II kerogen. The majority of the organic matter is structureless and occurs in the argillaceous-calcareous matrix. Structured organic matter appears predominantly as alginite, in particular the algae "tasmanite" is noticeable. The TOC content ranges up to 16 wt% with a high bitumen content. The mineral content characterizes the Posidonia Shale as a marlstone or mudstone with varying clay-calcite ratios. The quartz and pyrite content reaches up to 20 wt% and 9 wt%, respectively. The rock fabric is characterized by a fine grained and laminated matrix. The mean porosity lies between 4 and 12 %. Fractures other than those introduced by sample preparation were not observed. The Posidonia Shale is predicted to have an excellent source rock potential and will generate intermediate, P-N-A low wax oil when exposed to higher P-T-conditions ("oil kitchen"). Contact surfaces between the kerogen and matrix will be vulnerable to pressure induced fracturing caused by hydrocarbon formation. Additional porosity will be formed during maturation due to the

  8. Fe-Ni Micrometorites from Upper Jurassic Cañadon Asfalto Fm., Patagonia, Argentina

    Science.gov (United States)

    Matteini, M.; Hauser, N.; Cabaleri, N.; Silva Nieto, D.; Cuadros, F. A.; Reyes, S.

    2014-09-01

    Microspherules from an upper Jurassic sediments from Patagonia, show mineralogical, geochemical and textural features very similar to those reported for I-type micrometeorites whereas some spherules are interpreted as typical G-type micrometeorites.

  9. Swelling behaviour of Early Jurassic shales when exposed to water vapour

    Science.gov (United States)

    Houben, Maartje; Barnhoorn, Auke; Peach, Colin; Drury, Martyn

    2017-04-01

    The presence of water in mudrocks has a largely negative impact on production of gas, due to the fact that water causes swelling of the rock. Removing the water from the mudrock on the other hand could potentially shrink the rock and increase the matrix permeability. Investigation of the swelling/shrinkage behaviour of the rock during exposure to water vapour is of key importance in designing and optimizing unconventional production strategies. We have used outcrop samples of the Whitby Mudstone and the Posidonia shale [1], potential unconventional sources for gas in North-western Europe, to measure the swelling and shrinkage behaviour. Subsamples, 1 mm cubes, were prepared by the Glass Workshop at Utrecht University using a high precision digitally controlled diamond wafering saw cooled by air. The mm cubes were then exposed to atmospheres with different relative humidities either in an Environmental Scanning Electron Microscope (ESEM) or in a 3D dilatometer. So that the sample responses to exposure of water vapour could be measured. Parallel to the bedding we found a swelling strain between 0.5 and 1.5 %, perpendicular to the bedding though swelling strain varied between 1 and 3.5%. Volumetric swelling strain varied between 1 and 2% at a maximum relative humidity of 95%. Volumetric swelling strains measured in the Early Toarcian Shales are similar to the ones found in coal [2], where the results suggest that it might be possible to increase permeability in the reservoir by decreasing the in-situ water activity due to shrinkage of the matrix. [1] M.E. Houben, A. Barnhoorn, L. Wasch, J. Trabucho-Alexandre, C. J. Peach, M.R. Drury (2016). Microstructures of Early Jurassic (Toarcian) shales of Northern Europe, International Journal of Coal Geology, 165, 76-89. [2] Jinfeng Liu, Colin J. Peach, Christopher J. Spiers (2016). Anisotropic swelling behaviour of coal matrix cubes exposed to water vapour: Effects of relative humidity and sample size, International Journal of

  10. Chapter 2. Assessment of undiscovered conventional oil and gas resources--Upper Jurassic-Lower Cretaceous Cotton Valley group, Jurassic Smackover interior salt basins total petroleum system, in the East Texas basin and Louisiana-Mississippi salt basins provinces.

    Science.gov (United States)

    Dyman, T.S.; Condon, S.M.

    2006-01-01

    The Jurassic Smackover Interior Salt Basins Total Petroleum System is defined for this assessment to include (1) Upper Jurassic Smackover Formation carbonates and calcareous shales and (2) Upper Jurassic and Lower Cretaceous Cotton Valley Group organic-rich shales. The Jurassic Smackover Interior Salt Basins Total Petroleum System includes four conventional Cotton Valley assessment units: Cotton Valley Blanket Sandstone Gas (AU 50490201), Cotton Valley Massive Sandstone Gas (AU 50490202), Cotton Valley Updip Oil and Gas (AU 50490203), and Cotton Valley Hypothetical Updip Oil (AU 50490204). Together, these four assessment units are estimated to contain a mean undiscovered conventional resource of 29.81 million barrels of oil, 605.03 billion cubic feet of gas, and 19.00 million barrels of natural gas liquids. The Cotton Valley Group represents the first major influx of clastic sediment into the ancestral Gulf of Mexico. Major depocenters were located in south-central Mississippi, along the Louisiana-Mississippi border, and in northeast Texas. Reservoir properties and production characteristics were used to identify two Cotton Valley Group sandstone trends across northern Louisiana and east Texas: a high-permeability blanket-sandstone trend and a downdip, low-permeability massive-sandstone trend. Pressure gradients throughout most of both trends are normal, which is characteristic of conventional rather than continuous basin-center gas accumulations. Indications that accumulations in this trend are conventional rather than continuous include (1) gas-water contacts in at least seven fields across the blanket-sandstone trend, (2) relatively high reservoir permeabilities, and (3) high gas-production rates without fracture stimulation. Permeability is sufficiently low in the massive-sandstone trend that gas-water transition zones are vertically extensive and gas-water contacts are poorly defined. The interpreted presence of gas-water contacts within the Cotton Valley

  11. Upper Paleozoic Marine Shale Characteristics and Exploration Prospects in the Northwestern Guizhong Depression, South China

    Science.gov (United States)

    Zhu, Zhenhong; Yao, Genshun; Lou, Zhanghua; Jin, Aimin; Zhu, Rong; Jin, Chong; Chen, Chao

    2018-05-01

    Multiple sets of organic-rich shales developed in the Upper Paleozoic of the northwestern Guizhong Depression in South China. However, the exploration of these shales is presently at a relatively immature stage. The Upper Paleozoic shales in the northwestern Guizhong Depression, including the Middle Devonian Luofu shale, the Nabiao shale, and the Lower Carboniferous Yanguan shale, were investigated in this study. Mineral composition analysis, organic matter analysis (including total organic carbon (TOC) content, maceral of kerogen and the vitrinite reflection (Ro)), pore characteristic analysis (including porosity and permeability, pore type identification by SEM, and pore size distribution by nitrogen sorption), methane isothermal sorption test were conducted, and the distribution and thickness of the shales were determined, Then the characteristics of the two target shales were illustrated and compared. The results show that the Upper Paleozoic shales have favorable organic matter conditions (mainly moderate to high TOC content, type I and II1 kerogen and high to over maturity), good fracability potential (brittleness index (BI) > 40%), multiple pore types, stable distribution and effective thickness, and good methane sorption capacity. Therefore, the Upper Paleozoic shales in the northern Guizhong Depression have good shale gas potential and exploration prospects. Moreover, the average TOC content, average BI, thickness of the organic-rich shale (TOC > 2.0 wt%) and the shale gas resources of the Middle Devonian shales are better than those of the Lower Carboniferous shale. The Middle Devonian shales have better shale gas potential and exploration prospects than the Lower Carboniferous shales.

  12. Geomechanical and anisotropic acoustic properties of Lower Jurassic Posidonia Shales from Whitby (UK)

    NARCIS (Netherlands)

    Zhubayev, Alimzhan; Houben, Maartje|info:eu-repo/dai/nl/370588843; Smeulders, David; Barnhoorn, Auke|info:eu-repo/dai/nl/304843636

    2014-01-01

    The Posidonia Shale Formation (PSF) is one of the possible resource shales for unconventional gas in Northern Europe and currently is of great interest to hydrocarbon exploration and production. Due to low permeability of shales, economically viable production requires hydraulic fracturing of the

  13. New finds of stegosaur tracks from the Upper Jurassic Lourinhã formation, Portugal

    DEFF Research Database (Denmark)

    Mateus, Octavio; Milàn, Jesper; Romano, Michael

    2011-01-01

    Eleven new tracks from the Upper Jurassic of Portugal are described and attributed to the stegosaurian ichnogenus Deltapodus. One track exhibits exceptionally well−preserved impressions of skin on the plantar surface, showing the stegosaur foot to be covered by closely spaced skin tubercles of ca...

  14. First records of crocodyle and pterosaur tracks in the Upper Jurassic of Portugal

    DEFF Research Database (Denmark)

    Mateus, Octavio; Milàn, Jesper

    2010-01-01

    The Upper Jurassic of Portugal has a rich vertebrate fauna well documented from both body and trace fossils. Although the occurrence of crocodyles and pterosaurs is well documented from body fossils, trace fossils from both groups were unknown until now. Here we describe an isolated crocodyle-lik...

  15. A new spelaeogriphacean (Crustacea: Peracarida) from the Upper Jurassic of China

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    Yan-bin, Shen; Taylor, Rod S.; Schram, Frederick R.

    1998-01-01

    A new monotypic genus of Spelaeogriphacea is described from the Upper Jurassic of Liaoning Province, north-east China. This new genus and species brings the number of known spelaeogriphacean taxa to four, the others being two recent forms from Brazil and South Africa, and one from the Carboniferous

  16. Review of the Upper Jurassic-Lower Cretaceous stratigraphy in Western Cameros basin, Northern Spain

    DEFF Research Database (Denmark)

    Vidal, Maria del Pilar Clemente

    2010-01-01

    The Upper Jurassic-Lower Cretaceous stratigraphy of the Cameros basin has been reviewed. In Western Cameros the stratigraphic sections are condensed but they have a parallel development with the basin depocentre and the same groups have been identified. The Tera Group consists of two formations: ...

  17. Integrated Modeling and Carbonate Reservoir Analysis, Upper Jurassic Smackover Formation, Fishpond Field, Southwest Alabama

    Science.gov (United States)

    Owen, Alexander Emory

    This field case study focuses on Upper Jurassic (Oxfordian) Smackover hydrocarbon reservoir characterization, modeling and evaluation at Fishpond Field, Escambia County, Alabama, eastern Gulf Coastal Plain of North America. The field is located in the Conecuh Embayment area, south of the Little Cedar Creek Field in Conecuh County and east of Appleton Field in Escambia County. In the Conecuh Embayment, Smackover microbial buildups commonly developed on Paleozoic basement paleohighs in an inner to middle carbonate ramp setting. The microbial and associated facies identified in Fishpond Field are: (F-1) peloidal wackestone, (F-2) peloidal packstone, (F-3) peloidal grainstone, (F-4) peloidal grainstone/packstone, (F-5) microbially-influenced wackestone, (F-6) microbially-influenced packstone, (F-7) microbial boundstone, (F-8) oolitic grainstone, (F-9) shale, and (F-10) dolomitized wackestone/packstone. The Smackover section consists of an alternation of carbonate facies, including F-1 through F-8. The repetitive vertical trend in facies indicates variations in depositional conditions in the area as a result of changes in water depth, energy conditions, salinity, and/or water chemistry due to temporal variations or changes in relative sea level. Accommodation for sediment accumulation also was produced by a change in base level due to differential movement of basement rocks as a result of faulting and/or subsidence due to burial compaction and extension. These changes in base level contributed to the development of a microbial buildup that ranges between 130-165 ft in thickness. The Fishpond Field carbonate reservoir includes a lower microbial buildup interval, a middle grainstone/packstone interval and an upper microbial buildup interval. The Fishpond Field has sedimentary and petroleum system characteristics similar to the neighboring Appleton and Little Cedar Creek Fields, but also has distinct differences from these Smackover fields. The characteristics of the

  18. Deep-burial microporosity in upper Jurassic Haynesville oolitic grainstones, East Texas

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    Dravis, Jeffrey J.

    1989-07-01

    Secondary micromoldic porosity generated during deep-burial diagenesis occurs pervasively in Upper Jurassic Haynesville oolitic grainstones in East Texas and constitutes the major pore type in these gas reservoirs. Petrographic and geochemical relationships establish that development of this microporosity postdates emplacement of bitumen and most pressure solution fabrics in the reservoir grainstones. Microporosity development is strictly controlled by depositional texture and is restricted to either active shoal complex grainstones or thicker grainstones shed downramp by storm processes. Haynesville diagenetic and porosity relationships are consistent along the entire length of the east flank of the East Texas Basin, a distance greater than 100 km; identical relationships have also been observed along the west flank of this basin. Haynesville micromoldic porosity development is confined principally to ooids but also occurs in normally "stable" calcitic skeletal grains like oysters. Resultant micropores are a few microns across or less; complete dissolution of ooids to form oomoldic macroporosity is not observed in Haynesville limestones. Nearly all primary porosity in the Haynesville is now occluded by carbonate cement. Confirmation of a late, deep-burial origin for Haynesville secondary microporosity is based on physical relationships observed in numerous cores, regional petrography and geochemical data. Collectively, these observations demonstrate that Haynesville sediments were never locally or regionally exposed to freshwater but have undergone progressive burial diagenesis punctuated by a major late dissolution event which created the microporosity. Key observations which support Haynesville deep-burial microporosity development include: (1) petrographic relationships which demonstrate microporosity developed after emplacement of bitumen; (2) lack of subaerial exposure features in core, both atop shoal complexes and at the contact between the Haynesville and

  19. UPPER JURASSIC OUTCROPS ALONG THE CALDAS DA RAINHA DIAPIR, WEST CENTRAL PORTUGAL: A REGIONAL GEOHERITAGE OVERVIEW

    OpenAIRE

    DINIS, JORGE; BERNARDES, CRISTINA

    2004-01-01

    The Mesozoic Portuguese geological heritage is very rich and varied, a legacy of the position in the western margin of Iberia and its relationship with the evolution of the North Atlantic, with an interesting tectonic history since the Late Triassic. Regarding the Upper Jurassic several connections can be established between the tectonics and the stratigraphic record in the area surrounding the Caldas da Rainha structure: the basement and salt pillow control on deposition; the beginning of a ...

  20. Basin geodynamics and sequence stratigraphy of Upper Triassic to Lower Jurassic deposits of Southern Tunisia

    Science.gov (United States)

    Carpentier, Cédric; Hadouth, Suhail; Bouaziz, Samir; Lathuilière, Bernard; Rubino, Jean-Loup

    2016-05-01

    Aims of this paper are to propose a geodynamic and sequential framework for the late Triassic and early Jurassic of and south Tunisia and to evidence the impact of local tectonics on the stratigraphic architecture. Facies of the Upper Triassic to Lower Jurassic of Southern Tunisia have been interpreted in terms of depositional environments. A sequential framework and correlation schemes are proposed for outcrops and subsurface transects. Nineteen middle frequency sequences inserted in three and a half low frequency transgression/regression cycles were evidenced. Despite some datation uncertainties and the unknown durations of Lower Jurassic cycles, middle frequency sequences appear to be controlled by eustasy. In contrast the tectonics acted as an important control on low frequency cycles. The Carnian flooding was certainly favored by the last stages of a rifting episode which started during the Permian. The regression accompanied by the formation of stacked angular unconformities and the deposition of lowstand deposits during the late Carnian and Norian occured during the uplift and tilting of the northern basin margins. The transpressional activity of the Jeffara fault system generated the uplift of the Tebaga of Medenine high from the late Carnian and led to the Rhaetian regional angular Sidi Stout Unconformity. Facies analysis and well-log correlations permitted to evidence that Rhaetian to Lower Jurassic Messaoudi dolomites correspond to brecciated dolomites present on the Sidi Stout unconformity in the North Dahar area. The Early-cimmerian compressional event is a possible origin for the global uplift of the northern African margin and Western Europe during the late Carnian and the Norian. During the Rhaetian and the early Jurassic a new episode of normal faulting occured during the third low frequency flooding. This tectonosedimentary evolution ranges within the general geodynamic framework of the north Gondwana margin controlled by the opening of both

  1. Middle-Upper Triassic and Middle Jurassic tetrapod track assemblages of southern Tunisia, Sahara Platform

    Science.gov (United States)

    Niedźwiedzki, Grzegorz; Soussi, Mohamed; Boukhalfa, Kamel; Gierliński, Gerard D.

    2017-05-01

    Three tetrapod track assemblages from the early-middle Mesozoic of southern Tunisia are reported. The strata exposed at the Tejra 2 clay-pit near the Medenine and Rehach site, located in the vicinity of Kirchaou, contain the first tetrapod tracks found in the Triassic of Tunisia. The Middle Jurassic (early Aalenian) dinosaur tracks are reported from the Mestaoua plain near Tataouine. In the Middle Triassic outcrop of the Tejra 2 clay-pit, tridactyl tracks of small and medium-sized dinosauromorphs, were discovered. These tracks represent the oldest evidence of dinosaur-lineage elements in the Triassic deposits of Tunisia. Similar tracks have been described from the Middle Triassic of Argentina, France and Morocco. An isolated set of the manus and pes of a quadrupedal tetrapod discovered in Late Triassic Rehach tracksite is referred to a therapsid tracemaker. The Middle Jurassic deposits of the Mestaoua plain reveal small and large tridactyl theropod dinosaur tracks (Theropoda track indet. A-C). Based on comparison with the abundant record of Triassic tetrapod ichnofossils from Europe and North America, the ichnofauna described here indicates the presence of a therapsid-dinosauromorph ichnoassociation (without typical Chirotheriidae tracks) in the Middle and Late Triassic, which sheds light on the dispersal of the Middle-Upper Triassic tetrapod ichnofaunas in this part of Gondwana. The reported Middle Jurassic ichnofauna show close similarities to dinosaur track assemblages from the Lower and Middle Jurassic of northwestern Africa, North America, Europe and also southeastern Asia. Sedimentological and lithostratigraphic data of each new tracksite have been defined on published data and new observations. Taken together, these discoveries present a tantalizing window into the evolutionary history of tetrapods from the Triassic and Jurassic of southern Tunisia. Given the limited early Mesozoic tetrapod record from the region, these discoveries are of both temporal and

  2. Bioerosion and encrustation: Evidences from the Middle ‒ Upper Jurassic of central Saudi Arabia

    Science.gov (United States)

    El-Hedeny, Magdy; El-Sabbagh, Ahmed; Al Farraj, Saleh

    2017-10-01

    The Middle ‒ Upper Jurassic hard substrates of central Saudi Arabia displayed considerable signs of bioerosion and encrustations. They include organic (oysters, other bivalves, gastropods, corals and brachiopods) and an inorganic carbonate hardground that marks the boundary between the Middle Jurassic Tuwaiq Mountain Limestone and the Upper Jurassic Hanifa Formation. Traces of bioerosion in organic substrates include seven ichnotaxa produced by bivalves (Gastrochaenolites Leymerie, 1842), polychaete annelids (Trypanites Mägdefrau, 1932; MaeandropolydoraVoigt, 1965 and CaulostrepsisClarke, 1908), sponges (Entobia Bronn, 1837), acrothoracican cirripedes (Rogerella Saint-Seine, 1951), gastropods (Oichnus Bromley, 1981) and probable ?Centrichnus cf. eccentricus. The encrusting epifauna on these substrates consist of several organisms, including oysters, serpulid worms, corals and foraminifera. In contrast, the carbonate hardground was only bioeroded by Gastrochaenolite, Trypanites and Entobia. Epibionts on this hardground include ;Liostrea Douvillé, 1904-type; oysters, Nanogyra nana Sowerby, 1822 and serpulids. In general, bioerosion and encrustation are less diversified in hardground than in organic substrates, indicating a long time of exposition of organic substrates with slow to moderate rate of deposition in a restricted marine environment. Both organic and inorganic commuinities are correlated with those of other equatorial, subtropical and temperate equivalents.

  3. Sediment geology and halokinetic processes in the Upper Jurassic of Konrad mine, Bleckenstedter Mulde

    International Nuclear Information System (INIS)

    Ottomann, A.

    1991-01-01

    The Konrad mine is the only North German mine that is located in the Upper Jurassic. Lithologically, the sediment rock of the mine is not the same as in the rest of the Jurassic of Niedersachsen. The rock strata of the Bleckenstein trough are a special kind of facies. The report attempts to describe the effects of halokinetic movements on facies distribution. It describes the sedimentary and diagenetic, history of the whole Oxfordian and parts of the Kimmeridgian in the mine field on the basis of selected underground roadways. This necessitates a sufficient number of test points and sampled material. Sampling and mapping were carried out in the mine between January and July 1989. (orig.). 43 figs., 3 tabs [de

  4. Assessment of undiscovered continuous gas resources in Upper Devonian Shales of the Appalachian Basin Province, 2017

    Science.gov (United States)

    Enomoto, Catherine B.; Trippi, Michael H.; Higley, Debra K.; Rouse, William A.; Dulong, Frank T.; Klett, Timothy R.; Mercier, Tracey J.; Brownfield, Michael E.; Leathers-Miller, Heidi M.; Finn, Thomas M.; Marra, Kristen R.; Le, Phuong A.; Woodall, Cheryl A.; Schenk, Christopher J.

    2018-04-19

    Using a geology-based assessment methodology, the U.S. Geological Survey estimated mean undiscovered, technically recoverable continuous resources of 10.7 trillion cubic feet of natural gas in Upper Devonian shales of the Appalachian Basin Province.

  5. The bivalve Anopaea (Inoceramidae) from the Upper Jurassic-lowermost Cretaceous of Mexico

    Science.gov (United States)

    Zell, Patrick; Crame, J. Alistair; Stinnesbeck, Wolfgang; Beckmann, Seija

    2015-07-01

    In Mexico, the Upper Jurassic to lowermost Cretaceous La Casita and coeval La Caja and La Pimienta formations are well-known for their abundant and well-preserved marine vertebrates and invertebrates. The latter include conspicuous inoceramid bivalves of the genus Anopaea not formally described previously from Mexico. Anopaea bassei (Lecolle de Cantú, 1967), Anopaea cf. stoliczkai (Holdhaus, 1913), Anopaea cf. callistoensis Crame and Kelly, 1995 and Anopaea sp. are rare constituents in distinctive Tithonian-lower Berriasian levels of the La Caja Formation and one Tithonian horizon of the La Pimienta Formation. Anopaea bassei was previously documented from the Tithonian of central Mexico and Cuba, while most other members of Anopaea described here are only known from southern high latitudes. The Mexican assemblage also includes taxa which closely resemble Anopaea stoliczkai from the Tithonian of India, Indonesia and the Antarctic Peninsula, and Anopaea callistoensis from the late Tithonian to ?early Berriasian of the Antarctic Peninsula. Our new data expand the palaeogeographical distribution of the high latitude Anopaea to the Gulf of Mexico region and substantiate faunal exchange, in the Late Jurassic-earliest Cretaceous, between Mexico and the Antarctic Realm.

  6. Architecture of an Upper Jurassic barrier island sandstone reservoir, Danish Central Graben:

    DEFF Research Database (Denmark)

    Johannessen, Peter N.; Nielsen, Lars H.; Nielsen, Lars

    2010-01-01

    An unusually thick (c. 88 m), transgressive barrier island and shoreface sandstone succession characterizes the Upper Jurassic Heno Formation reservoir of the Freja oil field situated on the boundary of Denmark and Norway. The development and preservation of such thick transgressive barrier island...... sands is puzzling since a barrier island typically migrates landwards during transgression and only a thin succession of back-barrier and shoreface sands is preserved. Investigation of the development and geometry of the Freja reservoir sandstones is problematic since the reservoir is buried c. 5 km...... and seismic resolution is inadequate for architectural analysis. Description of the reservoir sandstone bodies is thus based on sedimentological interpretation and correlation of seven wells, of which five were cored. Palaeotopography played a major role in the position and preservation of the thick reservoir...

  7. Parameters controlling fracturing distribution: example of an Upper Jurassic marly-calcareous formation (eastern Paris Basin)

    International Nuclear Information System (INIS)

    Andre, G.; Rebours, H.; Wileveau, Y.; Proudhon, B.

    2006-01-01

    Study of fractures along a 490-m vertical section of marl/limestone alternations in the Upper Jurassic (Meuse/Haute-Marne underground research laboratory-eastern Paris Basin) reveals their organization and the different states of palaeo-stress. Type and extension of tectonic structures seem to be controlled principally by lithology and secondary by depth. Also, it appears deviations of Alpine palaeo-stresses between Kimmeridgian and Oxfordian formations. These deviations are related to the presence of marl/limestone contacts. The vertical evolution of current horizontal maximum stress shows a similar behaviour, with deviations at the walls of Callovo-Oxfordian argilites. These results allow us to point out and to discuss the impact of lithology, rheology and depth on fracturing occurrence and distribution. Furthermore, this study suggests the role of Callovo-Oxfordian as a barrier for fracture development between the limestones of Dogger and Oxfordian formations. (authors)

  8. Thermo-mechanical Properties of Upper Jurassic (Malm) Carbonate Rock Under Drained Conditions

    Science.gov (United States)

    Pei, Liang; Blöcher, Guido; Milsch, Harald; Zimmermann, Günter; Sass, Ingo; Huenges, Ernst

    2018-01-01

    The present study aims to quantify the thermo-mechanical properties of Neuburger Bankkalk limestone, an outcrop analog of the Upper Jurassic carbonate formation (Germany), and to provide a reference for reservoir rock deformation within future enhanced geothermal systems located in the Southern German Molasse Basin. Experiments deriving the drained bulk compressibility C were performed by cycling confining pressure p c between 2 and 50 MPa at a constant pore pressure p p of 0.5 MPa after heating the samples to defined temperatures between 30 and 90 °C. Creep strain was then measured after each loading and unloading stage, and permeability k was obtained after each creep strain measurement. The drained bulk compressibility increased with increasing temperature and decreased with increasing differential pressure p d = p c - p p showing hysteresis between the loading and unloading stages above 30 °C. The apparent values of the indirectly calculated Biot coefficient α ind containing contributions from inelastic deformation displayed the same temperature and pressure dependencies. The permeability k increased immediately after heating and the creep rates were also temperature dependent. It is inferred that the alteration of the void space caused by temperature changes leads to the variation of rock properties measured under isothermal conditions while the load cycles applied under isothermal conditions yield additional changes in pore space microstructure. The experimental results were applied to a geothermal fluid production scenario to constrain drawdown and time-dependent effects on the reservoir, overall, to provide a reference for the hydromechanical behavior of geothermal systems in carbonate, and more specifically, in Upper Jurassic lithologies.

  9. Depositional architecture and sequence stratigraphy of the Upper Jurassic Hanifa Formation, central Saudi Arabia

    Science.gov (United States)

    El-Sorogy, Abdelbaset; Al-Kahtany, Khaled; Almadani, Sattam; Tawfik, Mohamed

    2018-03-01

    To document the depositional architecture and sequence stratigraphy of the Upper Jurassic Hanifa Formation in central Saudi Arabia, three composite sections were examined, measured and thin section analysed at Al-Abakkayn, Sadous and Maashabah mountains. Fourteen microfacies types were identified, from wackestones to boundstones and which permits the recognition of five lithofacies associations in a carbonate platform. Lithofacies associations range from low energy, sponges, foraminifers and bioclastic burrowed offshoal deposits to moderate lithoclstic, peloidal and bioclastic foreshoal deposits in the lower part of the Hanifa while the upper part is dominated by corals, ooidal and peloidal high energy shoal deposits to moderate to low energy peloidal, stromatoporoids and other bioclastics back shoal deposits. The studied Hanifa Formation exhibits an obvious cyclicity, distinguishing from vertical variations in lithofacies types. These microfacies types are arranged in two third order sequences, the first sequence is equivalent to the lower part of the Hanifa Formation (Hawtah member) while the second one is equivalent to the upper part (Ulayyah member). Within these two sequences, there are three to six fourth-order high frequency sequences respectively in the studied sections.

  10. Restoration of Circum-Arctic Upper Jurassic source rock paleolatitude based on crude oil geochemistry

    Science.gov (United States)

    Peters, K.E.; Ramos, L.S.; Zumberge, J.E.; Valin, Z.C.; Scotese, C.R.

    2008-01-01

    Tectonic geochemical paleolatitude (TGP) models were developed to predict the paleolatitude of petroleum source rock from the geochemical composition of crude oil. The results validate studies designed to reconstruct ancient source rock depositional environments using oil chemistry and tectonic reconstruction of paleogeography from coordinates of the present day collection site. TGP models can also be used to corroborate tectonic paleolatitude in cases where the predicted paleogeography conflicts with the depositional setting predicted by the oil chemistry, or to predict paleolatitude when the present day collection locality is far removed from the source rock, as might occur due to long distance subsurface migration or transport of tarballs by ocean currents. Biomarker and stable carbon isotope ratios were measured for 496 crude oil samples inferred to originate from Upper Jurassic source rock in West Siberia, the North Sea and offshore Labrador. First, a unique, multi-tiered chemometric (multivariate statistics) decision tree was used to classify these samples into seven oil families and infer the type of organic matter, lithology and depositional environment of each organofacies of source rock [Peters, K.E., Ramos, L.S., Zumberge, J.E., Valin, Z.C., Scotese, C.R., Gautier, D.L., 2007. Circum-Arctic petroleum systems identified using decision-tree chemometrics. American Association of Petroleum Geologists Bulletin 91, 877-913]. Second, present day geographic locations for each sample were used to restore the tectonic paleolatitude of the source rock during Late Jurassic time (???150 Ma). Third, partial least squares regression (PLSR) was used to construct linear TGP models that relate tectonic and geochemical paleolatitude, where the latter is based on 19 source-related biomarker and isotope ratios for each oil family. The TGP models were calibrated using 70% of the samples in each family and the remaining 30% of samples were used for model validation. Positive

  11. The Upper Jurassic Stanleyville Group of the eastern Congo Basin: An example of perennial lacustrine system

    Science.gov (United States)

    Caillaud, Alexis; Blanpied, Christian; Delvaux, Damien

    2017-08-01

    The intracratonic Congo Basin, located in the Democratic Republic of Congo (DRC), is the largest sedimentary basin of Africa. The Jurassic strata outcrop along its eastern margin, south of Kisangani (formerly Stanleyville). In the last century, the Upper Jurassic Stanleyville Group was described as a lacustrine series containing a thin basal marine limestone designed as the ;Lime Fine; beds. Since the proposal of this early model, the depositional environment of the Stanleyville Group, and especially the possible marine incursion, has been debated, but without re-examining the existing cores, outcrop samples and historical fossils from the type location near Kisangani that are available at the Royal Museum for Central Africa (MRAC/KMMA, Tervuren, Belgium). In order to refine the former sedimentology, a series of nine exploration cores drilled in the Kisangani sub-basin have been described. This study aims at integrating sedimentary facies in existing sedimentary models and to discuss the hypothesis of the presence of Kimmeridgian marine deposits along the Congo River near Kisangani, a region which lies in the middle of the African continent. Eight facies have been identified, which permit a reinterpretation of the depositional environment and paleogeography of the Stanleyville Group. The base of the Stanleyville Group is interpreted to represent a conglomeratic fluvial succession, which filled an inherited Triassic paleotopography. Above these conglomerates, a transition to a typically lacustrine system is interpreted, which includes: (1) a basal profundal, sublittoral (brown to dark fine-grained siltstones with microbial carbonates, i.e., the ;Lime Fine; beds) and littoral lacustrine series; covered by (2) a sublittoral to profundal interval (brown to dark organic-rich, fine-grained siltstones), which corresponds to the maximum extent of the paleo-lake; and, finally (3) a shallow lacustrine series (greenish calcareous siltstones and sandstones with red siltstones

  12. UPPER JURASSIC OUTCROPS ALONG THE CALDAS DA RAINHA DIAPIR, WEST CENTRAL PORTUGAL: A REGIONAL GEOHERITAGE OVERVIEW

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    JORGE DINIS

    2004-03-01

    Full Text Available The Mesozoic Portuguese geological heritage is very rich and varied, a legacy of the position in the western margin of Iberia and its relationship with the evolution of the North Atlantic, with an interesting tectonic history since the Late Triassic. Regarding the Upper Jurassic several connections can be established between the tectonics and the stratigraphic record in the area surrounding the Caldas da Rainha structure: the basement and salt pillow control on deposition; the beginning of a diapiric and magmatic cycle associated to the on-set of sea-floor and the exhumation of both Jurassic deposits and the core of their controlling diapirs. The nature of the outcrops and richness in sedimentary environments, related with the different phases of rifting, is a remarkable case for extensional basin studies. Geological sites can be of regional, national or international importance due to scientific, educational, economical, social or historical reasons. The present proposal can be considered as a model for the establishment of tourist/educational routes with a strong component in communication on Earth Sciences, integrating social and historical aspects at a regional level. The recognition of those sites as geoheritage may contribute to a more sustainable management, in particular because it allows the achievement of a critical dimension for the investment in human resources and marketing. In Portugal, recent legal evolution might be considered promising. Nevertheless, since implementation of the concept of protected site depends on the approval of detailed management programs, there are frequent delays, misinterpretations and disrespect of legislation. The strategy to be adopted must integrate conservation, scientific studies and science communication in projects with economic and social interest.

  13. Sedimentology and palaeontology of upper Karoo aeolian strata (Early Jurassic) in the Tuli Basin, South Africa

    Science.gov (United States)

    Bordy, Emese M.; Catuneanu, Octavian

    2002-08-01

    The Karoo Supergroup in the Tuli Basin (South Africa) consists of a sedimentary sequence composed of four stratigraphic units, namely the Basal, Middle and Upper units, and Clarens Formation. The units were deposited in continental settings from approximately Late Carboniferous to Middle Jurassic. This paper focuses on the Clarens Formation, which was examined in terms of sedimentary facies and palaeo-environments based on evidence provided by primary sedimentary structures, palaeo-flow measurements and palaeontological findings. Two main facies associations have been identified: (i) massive and large-scale planar cross-bedded sandstones of aeolian origin; and (ii) horizontally and cross-stratified sandstones of fluvial origin. Most of the sandstone lithofacies of the Clarens Formation were generated as transverse aeolian dunes produced by northwesterly winds in a relatively wet erg milieu. Direct evidence of aquatic subenvironments comes from local small ephemeral stream deposits, whereas palaeontological data provide indirect evidence. Fossils of the Clarens Formation include petrified logs of Agathoxylon sp. wood type and several trace fossils which were produced by insects and vertebrates. The upper part of the Clarens Formation lacks both direct and indirect evidence of aquatic conditions, and this suggests aridification that led to the dominance of dry sand sea conditions.

  14. Resedimented Limestones in Middle and Upper Jurassic Succession of the Slovenian Basin

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    Boštjan Rožič

    2006-12-01

    Full Text Available The Middle and Upper Jurassic succession of the Slovenian Basin is characterized by pelagic sedimentation of siliceous limestones and radiolarian cherts. In the southern and central part of the basin two packages of resedimented limestones are interbedded within pelagic sediments. The Lower resedimented limestones are lower-middle Bajocian to lower Callovian in age. In the southern part of the basin they form laterally discontinuous sequences composed of limestone breccias, calcarenites and micritic limestone and in the central part of the basin calcarenite intercalations within pelagic beds. They were transported by turbidity currents from highly productive ooidal shoals of the Dinaric Carbonate Platform. The Lower resedimented carbonates correlate with the lower three members of the Travnik Formation in the Bovec Trough and similarly developed but much thicker Vajont Formation in the Belluno Basin. The difference in thickness is interpreted as a consequence of shallow-water and longshore currents on the Dinaric Carbonate Platform that transported platform material towards southwest in the direction of the Belluno Basin. The Upper resedimented limestones are upper Kimmeridgian to lower Tithonian and occur within radiolarian cherts in the upper part of the succession as calcarenite beds that originated by turbidity currents. Onset of resedimentation coincides with the emersion-related demise of barrier reef and following deposition of micritic and rare oolitic limestones on the Dinaric Carbonate Platform. Approximatelly coeval resedimented limestones occur in the fourth member of the Travnik Formation in the Bovec Trough, but are not reported from the Ammonitico Rosso Superiore Formation in the Belluno Basin.

  15. Definition of Greater Gulf Basin Lower Cretaceous and Upper Cretaceous Lower Cenomanian Shale Gas Assessment Unit, United States Gulf of Mexico Basin Onshore and State Waters

    Science.gov (United States)

    Dennen, Kristin O.; Hackley, Paul C.

    2012-01-01

    An assessment unit (AU) for undiscovered continuous “shale” gas in Lower Cretaceous (Aptian and Albian) and basal Upper Cretaceous (lower Cenomanian) rocks in the USA onshore Gulf of Mexico coastal plain recently was defined by the U.S. Geological Survey (USGS). The AU is part of the Upper Jurassic-Cretaceous-Tertiary Composite Total Petroleum System (TPS) of the Gulf of Mexico Basin. Definition of the AU was conducted as part of the 2010 USGS assessment of undiscovered hydrocarbon resources in Gulf Coast Mesozoic stratigraphic intervals. The purpose of defining the Greater Gulf Basin Lower Cretaceous Shale Gas AU was to propose a hypothetical AU in the Cretaceous part of the Gulf Coast TPS in which there might be continuous “shale” gas, but the AU was not quantitatively assessed by the USGS in 2010.

  16. Tetradactyl footprints of an unknown affinity theropod dinosaur from the Upper Jurassic of Morocco.

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    Jaouad Nouri

    Full Text Available BACKGROUND: New tetradactyl theropod footprints from Upper Jurassic (Oxfordian-Kimmeridgian have been found in the Iouaridène syncline (Morocco. The tracksites are at several layers in the intermediate lacustrine unit of Iouaridène Formation. The footprints were named informally in previous works "Eutynichnium atlasipodus". We consider as nomen nudum. METHODOLOGY/PRINCIPAL FINDINGS: Boutakioutichnium atlasicus ichnogen. et ichnosp. nov. is mainly characterized by the hallux impression. It is long, strong, directed medially or forward, with two digital pads and with the proximal part of the first pad in lateral position. More than 100 footprints in 15 trackways have been studied with these features. The footprints are large, 38-48 cm in length, and 26-31 cm in width. CONCLUSIONS/SIGNIFICANCE: Boutakioutichnium mainly differs from other ichnotaxa with hallux impression in lacking metatarsal marks and in not being a very deep footprint. The distinct morphology of the hallux of the Boutakioutichnium trackmaker -i.e. size and hallux position- are unique in the dinosaur autopodial record to date.

  17. Evidence for long term deep CO2 confinement below thick Jurassic shales at Montmiral site (SE Basin of France)

    Science.gov (United States)

    Rubert, Y.; Ramboz, C.; Le Nindre, Y. M.; Lerouge, C.; Lescanne, M.

    2009-04-01

    basement; - Middle unit: Triassic-Liassic reservoir; - Upper unit: late Jurassic to Cretaceous. The middle unit (reservoir) and the upper unit are separated by the thick, tight seal, Domerian to Oxfordian in age. The definition of these lithological units was made using combined petrographic techniques (cathodoluminescence CL, fluorescence, Raman spectroscopy, crushing tests), geochemical techniques (C and O isotopes) and microthermometry. Lower unit: Paleozoïc basement - In the metamorphic basement, aquo-carbonic and CO2-dominant fluids are trapped as primary fluid inclusions in hydrothermal barite and fluoroapatite, and as secondary fluid inclusions in extensionnal microcracks crosscutting metamorphic quartz. All these fluids, trapped in the two-phase stability field, indicate firstly a limited phase separation at 300°C and 400-500 bars evolving toward wider CO2-H2O unmixing at 200°C and 200 bars. Basinal saline brines (10 and 15-25 wt % eq. NaCl and 70temperature (80°C) marine origin fluids equilibrated with surrounding rocks (Delta18O ~ 0,5 permil SMOW) and a late circulation of lower temperature (52°C) meteoric fluids also equilibrated with limestones (Delta18O ~ -7 permil SMOW). CO2 inclusions belong to the latest phase of fracturing, occurring during the meteoric fluids circulation phase. These open fractures, with dog-tooth style euhedral calcite, exhibit, by comparison with the outcrop, a fabric of typical Pyrenean type. Upper unit: late Jurassic to Cretaceous - Above the seal, the fractures are exclusively filled with carbonates (calcite and dolomite) trapping aqueous fluid inclusions only. CL, microthermometry and isotopic data provide evidence for low temperature meteoric fluids (Delta18O ~ -5 permil SMOW) with numerous karstic features in Cretaceous strata. In conclusion, the CO2 feeding phase occurred under high pressure conditions requiring the presence of a thick sedimentary cover. The cement phases in the reservoir and in the cover rock, which exhibit

  18. Discontinuities Characteristics of the Upper Jurassic Arab-D Reservoir Equivalent Tight Carbonates Outcrops, Central Saudi Arabia

    Science.gov (United States)

    Abdlmutalib, Ammar; Abdullatif, Osman

    2017-04-01

    Jurassic carbonates represent an important part of the Mesozoic petroleum system in the Arabian Peninsula in terms of source rocks, reservoirs, and seals. Jurassic Outcrop equivalents are well exposed in central Saudi Arabia and which allow examining and measuring different scales of geological heterogeneities that are difficult to collect from the subsurface due to limitations of data and techniques. Identifying carbonates Discontinuities characteristics at outcrops might help to understand and predict their properties and behavior in the subsurface. The main objective of this study is to identify the lithofacies and the discontinuities properties of the upper Jurassic carbonates of the Arab D member and the Jubaila Formation (Arab-D reservoir) based on their outcrop equivalent strata in central Saudi Arabia. The sedimentologic analysis revealed several lithofacies types that vary in their thickness, abundances, cyclicity and vertical and lateral stacking patterns. The carbonates lithofacies included mudstone, wackestone, packstone, and grainstone. These lithofacies indicate deposition within tidal flat, skeletal banks and shallow to deep lagoonal paleoenvironmental settings. Field investigations of the outcrops revealed two types of discontinuities within Arab D Member and Upper Jubaila. These are depositional discontinuities and tectonic fractures and which all vary in their orientation, intensity, spacing, aperture and displacements. It seems that both regional and local controls have affected the fracture development within these carbonate rocks. On the regional scale, the fractures seem to be structurally controlled by the Central Arabian Graben System, which affected central Saudi Arabia. While, locally, at the outcrop scale, stratigraphic, depositional and diagenetic controls appear to have influenced the fracture development and intensity. The fracture sets and orientations identified on outcrops show similarity to those fracture sets revealed in the upper

  19. A new upper jurassic ophthalmosaurid ichthyosaur from the Slottsmøya Member, Agardhfjellet formation of central Spitsbergen.

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    Aubrey Jane Roberts

    Full Text Available Abundant new ichthyosaur material has recently been documented in the Slottsmøya Member of the Agardhfjellet Formation from the Svalbard archipelago of Norway. Here we describe a partial skeleton of a new taxon, Janusaurus lundi, that includes much of the skull and representative portions of the postcranium. The new taxon is diagnosed by a suite of cranial character states including a very gracile stapedial shaft, the presence of a dorsal process on the prearticular and autapomorphic postcranial features such as the presence of an interclavicular trough and a conspicuous anterodorsal process of the ilium. The peculiar morphology of the ilia indicates a previously unrecognized degree of morphological variation in the pelvic girdle of ophthalmosaurids. We also present a large species level phylogenetic analysis of ophthalmosaurids including new and undescribed ichthyosaur material from the Upper Jurassic of Svalbard. Our results recover all Svalbard taxa in a single unresolved polytomy nested within Ophthalmosaurinae, which considerably increases the taxonomic composition of this clade. The paleobiogeographical implications of this result suggest the presence of a single clade of Boreal ophthalmosaurid ichthyosaurs that existed during the latest Jurassic, a pattern also reflected in the high degree of endemicity among some Boreal invertebrates, particularly ammonoids. Recent and ongoing descriptions of marine reptiles from the Slottsmøya Member Lagerstätte provide important new data to test hypotheses of marine amniote faunal turnover at the Jurassic-Cretaceous boundary.

  20. Multiple episodes of dolomitization and dolomite recrystallization during shallow burial in Upper Jurassic shelf carbonates: eastern Swabian Alb, southern Germany

    Science.gov (United States)

    Reinhold, C.

    1998-10-01

    The Upper Jurassic of the eastern Swabian Alb is composed of oolitic platform sands with associated microbe-siliceous sponge mounds at the platform margins. They are surrounded by argillaceous or calcareous mudstones and marl-limestone alternations, deposited in adjacent marl basins. Partial to complete dolomitization is predominantly confined to the mound facies. Six types of dolomite, as well as one type of ankerite, document a complex diagenetic history during shallow burial with multiple episodes of dolomite formation and recrystallization. The earliest massive matrix dolomitization is Ca-rich, has slightly depleted oxygen isotope values relative to Late Jurassic seawater, and carbon isotopic values in equilibrium with Late Jurassic seawater. This initial massive matrix dolomitization occurred during latest Jurassic to earliest Cretaceous and is related to pressure dissolution during very shallow burial at temperatures of at least 50°C. Hydrologic conditions and mass-balance calculations indicate that burial compaction provided sufficient fluids for dolomitization. Mg is derived from negligibly modified seawater, that was expelled from the adjacent off-reef strata into the mound facies. Position of the mounds along the platform margins controlled the distribution of the shallow-burial dolomite. Covariant trends between textural modification, increasing stoichiometry, partial changes in trace element content (Mn, Fe, Sr) and depletion in stable isotopes as well as distinctive CL pattern illustrate two recrystallization phases of the precursor matrix dolomite during further burial at elevated temperatures. Strong Sr enrichment of the second phase of recrystallized dolomite is ascribed to Sr-rich meteoric waters descending from overlying aragonite-bearing reef limestones or evaporite-bearing peritidal carbonates. Late-stage coarsely crystalline dolomite cements occur as vug and fracture fillings and formed during burial. Ankerite, associated with sulphide and

  1. Paleocurrents of the Middle-Upper Jurassic strata in the Paradox Basin, Colorado, inferred from anisotropy of magnetic susceptibility (AMS)

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    Ejembi, J. I.; Ferre, E. C.; Potter-McIntyre, S. L.

    2017-12-01

    The Middle-Upper Jurassic sedimentary strata in the southwestern Colorado Plateau recorded pervasive eolian to fluvio-lacustrine deposition in the Paradox Basin. While paleocurrents preserved in the Entrada Sandstone, an eolian deposition in the Middle Jurassic, has been well constrained and show a northwesterly to northeasterly migration of ergs from the south onto the Colorado Plateau, there is yet no clear resolution of the paleocurrents preserved in the Wanakah Formation and Tidwell Member of the Morrison Formation, both of which are important sedimentary sequences in the paleogeographic framework of the Colorado Plateau. New U-Pb detrital zircon geochronology of sandstones from these sequences suggests that an abrupt change in provenance occurred in the early Late Jurassic, with sediments largely sourced from eroding highlands in central Colorado. We measured the anisotropy of magnetic susceptibility (AMS) of sediments in oriented sandstone samples from these three successive sequences; first, to determine the paleocurrents from the orientations of the AMS fabrics in order to delineate the source area and sediments dispersal pattern and second, to determine the depositional mechanisms of the sediments. Preliminary AMS data from two study sites show consistency and clustering of the AMS axes in all the sedimentary sequences. The orientations of the Kmin - Kint planes in the Entrada Sandstone sample point to a NNE-NNW paleocurrent directions, which is in agreement with earlier studies. The orientations of the Kmin - Kint planes in the Wanakah Formation and Tidwell Member samples show W-SW trending paleocurrent directions, corroborating our hypothesis of a shift in provenance to the eroding Ancestral Front Range Mountain, located northeast of the Paradox Basin, during the Late Jurassic. Isothermal remanence magnetization (IRM) of the samples indicate that the primary AMS carriers are detrital, syndepositional ferromagnetic minerals. Thus, we contend that AMS can

  2. Facies analysis of an Upper Jurassic carbonate platform for geothermal reservoir characterization

    Science.gov (United States)

    von Hartmann, Hartwig; Buness, Hermann; Dussel, Michael

    2017-04-01

    The Upper Jurassic Carbonate platform in Southern Germany is an important aquifer for the production of geothermal energy. Several successful projects were realized during the last years. 3D-seismic surveying has been established as a standard method for reservoir analysis and the definition of well paths. A project funded by the federal ministry of economic affairs and energy (BMWi) started in 2015 is a milestone for an exclusively regenerative heat energy supply of Munich. A 3D-seismic survey of 170 square kilometer was acquired and a scientific program was established to analyze the facies distribution within the area (http://www.liag-hannover.de/en/fsp/ge/geoparamol.html). Targets are primarily fault zones where one expect higher flow rates than within the undisturbed carbonate sediments. However, since a dense net of geothermal plants and wells will not always find appropriate fault areas, the reservoir properties should be analyzed in more detail, e.g. changing the viewpoint to karst features and facies distribution. Actual facies interpretation concepts are based on the alternation of massif and layered carbonates. Because of successive erosion of the ancient land surfaces, the interpretation of reefs, being an important target, is often difficult. We found that seismic sequence stratigraphy can explain the distribution of seismic pattern and improves the analysis of different facies. We supported this method by applying wavelet transformation of seismic data. The splitting of the seismic signal into successive parts of different bandwidths, especially the frequency content of the seismic signal, changed by tuning or dispersion, is extracted. The combination of different frequencies reveals a partition of the platform laterally as well as vertically. A cluster analysis of the wavelet coefficients further improves this picture. The interpretation shows a division into ramp, inner platform and trough, which were shifted locally and overprinted in time by other

  3. The Frasnian-Famennian boundary (Upper Devonian) in black shale sequences: US Southern Midcontinent, Illinois Basin, and northern Appalachian Basin

    Energy Technology Data Exchange (ETDEWEB)

    Over, D.J. (State Univ. of New York, Geneseo, NY (United States). Dept. of Geological Sciences)

    1994-04-01

    The Frasnian-Famennian (F/F) boundary in the Woodford Shale of the US southern Midcontinent, Sweetland Creek Shale of the Illinois Basin, and the Hanover Shale of the northern Appalachian Basin is recognized to a discrete horizon. In each locality the boundary is marked by evidence of a disconformity: phosphate nodules, concentration of conodonts, or coated and corroded grains. The Woodford Shale consists of finely laminated pyritic organic-rich shale containing interbeds of greenish shale and chert. The F/F boundary horizon is marked by a concentration of conodonts and phosphatic nodules. The boundary lag horizon contains Pa. linguliformis, Pa. subperlobtata, Pa. delicatula delicatula, and Pa. triangularis. Underlying laminations contain Ancyrognathus ubiquitus and Pa. triangularis indicating that the disconformity is within the uppermost MN Zone 13 or Lower triangularis Zone. The upper portion of the Type Sweetland Creek Shale consists of dark organic-rich shales. The F/F boundary is located within an interval containing three green shale interbeds. Palmatolepis triangularis in the absence of Frasnian species first occurs in the middle green shale. In the thick Upper Devonian clastic sequence of the northern Appalachian Basin the F/F boundary is within an interval of interbedded pyritic green and organic-rich silty shales of the Hanover Shale. At Irish Gulf strata containing Pa. triangularis overlie finely laminated dark shales containing Pa. bogartensis, Pa. triangularis, Pa. winchell, Ancyrodella curvata, and Icriodus alternatus. The conodont fauna transition is below a conodont-rich laminae containing a Famennian fauna that marks the boundary horizon.

  4. Revisions to the original extent of the Devonian Shale-Middle and Upper Paleozoic Total Petroleum System

    Science.gov (United States)

    Enomoto, Catherine B.; Rouse, William A.; Trippi, Michael H.; Higley, Debra K.

    2016-04-11

    Technically recoverable undiscovered hydrocarbon resources in continuous accumulations are present in Upper Devonian and Lower Mississippian strata in the Appalachian Basin Petroleum Province. The province includes parts of New York, Pennsylvania, Ohio, Maryland, West Virginia, Virginia, Kentucky, Tennessee, Georgia, and Alabama. The Upper Devonian and Lower Mississippian strata are part of the previously defined Devonian Shale-Middle and Upper Paleozoic Total Petroleum System (TPS) that extends from New York to Tennessee. This publication presents a revision to the extent of the Devonian Shale-Middle and Upper Paleozoic TPS. The most significant modification to the maximum extent of the Devonian Shale-Middle and Upper Paleozoic TPS is to the south and southwest, adding areas in Tennessee, Georgia, Alabama, and Mississippi where Devonian strata, including potential petroleum source rocks, are present in the subsurface up to the outcrop. The Middle to Upper Devonian Chattanooga Shale extends from southeastern Kentucky to Alabama and eastern Mississippi. Production from Devonian shale has been established in the Appalachian fold and thrust belt of northeastern Alabama. Exploratory drilling has encountered Middle to Upper Devonian strata containing organic-rich shale in west-central Alabama. The areas added to the TPS are located in the Valley and Ridge, Interior Low Plateaus, and Appalachian Plateaus physiographic provinces, including the portion of the Appalachian fold and thrust belt buried beneath Cretaceous and younger sediments that were deposited on the U.S. Gulf Coastal Plain.

  5. Dinosaur ichnofauna of the Upper Jurassic/Lower Cretaceous of the Paraná Basin (Brazil and Uruguay)

    Science.gov (United States)

    Francischini, H.; Dentzien–Dias, P. C.; Fernandes, M. A.; Schultz, C. L.

    2015-11-01

    Upper Jurassic and Lower Cretaceous sedimentary layers are represented in the Brazilian Paraná Basin by the fluvio-aeolian Guará Formation and the Botucatu Formation palaeoerg, respectively, overlapped by the volcanic Serra Geral Formation. In Uruguay, the corresponding sedimentary units are named Batoví and Rivera Members (both from the Tacuarembó Formation), and the lava flows constitute the Arapey Formation (also in Paraná Basin). Despite the lack of body fossils in the mentioned Brazilian formations, Guará/Batoví dinosaur fauna is composed of theropod, ornithopod and wide-gauge sauropod tracks and isolated footprints, as well as theropod teeth. In turn, the Botucatu/Rivera dinosaur fauna is represented by theropod and ornithopod ichnofossils smaller than those from the underlying units. The analysis of these dinosaur ichnological records and comparisons with other global Mesozoic ichnofauna indicates that there is a size reduction in dinosaur fauna in the more arid Botucatu/Rivera environment, which is dominated by aeolian dunes. The absence of sauropod trackways in the Botucatu Sandstone fits with the increasingly arid conditions because it is difficult for heavy animals to walk on sandy dunes, as well as to obtain the required amount of food resources. This comparison between the Upper Jurassic and Lower Cretaceous dinosaur fauna in south Brazil and Uruguay demonstrates the influence of aridization on the size of animals occupying each habitat.

  6. Subsurface geology of the upper Devonian-lower Mississippian black-shale sequence in eastern Kentucky

    International Nuclear Information System (INIS)

    Dillman, S.B.

    1980-01-01

    The Upper Devonian-Lower Mississippi black-shale sequence is an important source of natural gas in eastern Kentucky and with technological advances may be an important source of synthetic oil and uranium on the flanks of the Cincinnati arch. To enhance the understanding and development of these resources in the black-shale sequence, eight isopach maps, eight structure-contour maps and nine isopach maps of highly radioactive black shale were constructed. Structural features including the Rome trough, Rockcastle River uplift, Pine Mountain thrust fault, Kentucky River and Paint Creek fault zones and unnamed basinal areas in Greenup, Pike, and Knott counties were identified on the maps. Faults bounding the Rome trough and other structures were active intermittently throughout Late Devonian time. Other structures show only post-Devonian activity, whereas some show both Devonian and post-Devonian activity. Comparison of structure-contour and isopach maps allow the differentiation of syn- and post-sedimentray structural activity relative to the black-shale sequence. A north-south trending hinge line separates a broad platform area from an area of rapid eastward thickening into the Appalachian basin. Units 7 through 1 progressively onlap the Cincinnati arch; units 4 through 1 cover the arch

  7. THE ROSSO AMMONITICO VERONESE (MIDDLE-UPPER JURASSIC OF THE TRENTO PLATEAU: A PROPOSALLITHOSTRATIGRAPHIC RDERING AND FORMALIZATION

    Directory of Open Access Journals (Sweden)

    LUCA MARTIRE

    2006-07-01

    Full Text Available We here propose a revision of the stratigraphic interval comprised between the top of platform carbonates, mainly of Early Jurassic age, and the base of the Maiolica, in the Trento Plateau. Most of this interval (upper Bajocian - upper Tithonian is represented by ammonite-bearing, red nodular limestones known with the historical name of Rosso Ammonitico Veronese (RAV. It has been subdivided in three units: a lower unit, calcareous and massively bedded; a middle unit, thinly bedded and cherty; and an upper unit, calcareous and nodular. In addition to these units, other sedimentary bodies are known below the base of the RAV. These are thin and discontinuous, such as the Lumachella a Posidonia alpina (LPa and the Calcari a Skirroceras (CSk, both spanning the upper Aalenian - upper Bajocian. A lithostratigraphic redefinition of the RAV is proposed by addition of two members (LPa e CSk to the three classical members. The new members are easily distinguished by their lithofacies and are always separated from the lower unit by discontinuities. Two sections located on the Altopiano di Asiago are described: Kaberlaba shows all the three members (lower, middle and upper and is proposed as the reference section for a formalization of the RAV; Rabeschini is characterized  by the absence of the middle member and may be held as a complementary section. The RAV lower boundary is everywhere very sharp and marked by a facies contrast; the upper boundary, instead, is transitional and is defined by a progressive change from red, nodular, Saccocoma packstones to white, non-nodular calpionellid wackestones. Calpionellid associations indicate that the upper boundary falls within the upper Tithonian.

  8. Reconstruction of the Upper Jurassic Morrison Formation extinct ecosystem—a synthesis

    Science.gov (United States)

    Turner, Christine E.; Peterson, Fred

    2004-05-01

    A synthesis of recent and previous studies of the Morrison Formation and related beds, in the context of a conceptual climatic/hydrologic framework, permits reconstruction of the Late Jurassic dinosaurian ecosystem throughout the Western Interior of the United States and Canada. Climate models and geologic evidence indicate that a dry climate persisted in the Western Interior during the Late Jurassic. Early and Middle Kimmeridgian eolian deposits and Late Kimmeridgian alkaline, saline wetland/lacustrine deposits demonstrate that dryness persisted throughout the Kimmeridgian. Tithonian-age coal reflects lower evaporation rates associated with a slight cooling trend, but not a significant climate change. With a subtropical high over the Paleo-Pacific Ocean and atmospheric circulation generally toward the east, moisture carried by prevailing winds "rained out" progressively eastward, leaving the continental interior—and the Morrison depositional basin—dry. Within the basin, high evaporation rates associated with the southerly paleolatitude and greenhouse effects added to the dryness. Consequently, the two main sources of water—groundwater and surface water—originated outside the basin, through recharge of regional aquifers and streams that originated in the western uplands. Precipitation that fell west of the basin recharged aquifers that underlay the basin and discharged in wetlands and lakes in the distal, low-lying part of the basin. Precipitation west of the basin also fed intermittent and scarce perennial streams that flowed eastward. The streams were probably "losing" streams in their upstream reaches, and contributed to a locally raised water table. Elsewhere in the basin, where the floodplain intersected the water table, small lakes dotted the landscape. Seasonal storms, perhaps in part from the Paleo-Gulf of Mexico, brought some precipitation directly to the basin, although it was also subjected to "rain out" en route. Thus, meteoric input to the

  9. Reconstruction of the Upper Jurassic Morrison Formation extinct ecosystem - A synthesis

    Science.gov (United States)

    Turner, C.E.; Peterson, F.

    2004-01-01

    A synthesis of recent and previous studies of the Morrison Formation and related beds, in the context of a conceptual climatic/hydrologic framework, permits reconstruction of the Late Jurassic dinosaurian ecosystem throughout the Western Interior of the United States and Canada. Climate models and geologic evidence indicate that a dry climate persisted in the Western Interior during the Late Jurassic. Early and Middle Kimmeridgian eolian deposits and Late Kimmeridgian alkaline, saline wetland/lacustrine deposits demonstrate that dryness persisted throughout the Kimmeridgian. Tithonian-age coal reflects lower evaporation rates associated with a slight cooling trend, but not a significant climate change. With a subtropical high over the Paleo-Pacific Ocean and atmospheric circulation generally toward the east, moisture carried by prevailing winds "rained out" progressively eastward, leaving the continental interior-and the Morrison depositional basin-dry. Within the basin, high evaporation rates associated with the southerly paleolatitude and greenhouse effects added to the dryness. Consequently, the two main sources of water-groundwater and surface water-originated outside the basin, through recharge of regional aquifers and streams that originated in the western uplands. Precipitation that fell west of the basin recharged aquifers that underlay the basin and discharged in wetlands and lakes in the distal, low-lying part of the basin. Precipitation west of the basin also fed intermittent and scarce perennial streams that flowed eastward. The streams were probably "losing" streams in their upstream reaches, and contributed to a locally raised water table. Elsewhere in the basin, where the floodplain intersected the water table, small lakes dotted the landscape. Seasonal storms, perhaps in part from the Paleo-Gulf of Mexico, brought some precipitation directly to the basin, although it was also subjected to "rain out" en route. Thus, meteoric input to the basin was

  10. Regional diagenesis of sandstone in the Upper Jurassic Morrison Formation, San Juan Basin, New Mexico and Colorado

    International Nuclear Information System (INIS)

    Hansley, P.L.

    1990-01-01

    The author reports that early authigenic mineral assemblages and vitroclastic textures are very well preserved in upper sandstones of the Upper Jurassic Morrison Formation. The distributions of the authigenic minerals were controlled, in part, by chemical gradients in a large saline, alkaline lake (Lake T'oo'dichi) that existed in late Morrison time. Sandstones on lake margins were cemented by smectite and silica, whereas sandstones nearer the lake center, in which waters were most saline and alkaline, were cemented by zeolites. Diagenetic alterations in sandstones were promoted by alkaline interstitial waters that emanated from adjacent fine-grained, tuffaceous lake beds. Metastable phases that precipitated first were replaced relatively quickly by more stable, ordered phases in the geochemically favorable environment of the closed basin setting. Elevation of temperatures above the geothermal gradient was proved by the influx of warm, deep-basin waters that locally modified early diagenetic assemblages during burial diagenesis. In organic- (and commonly also uranium ore-) bearing sandstones located primarily in the southern part of the basin, complex diagenetic assemblages resulted from water/rock reactions involving soluble organic complexes

  11. Biostratigraphy of the upper Bajocian-middle Callovian (Middle Jurassic), South America

    Science.gov (United States)

    Riccardi, A. C.; Westermann, G. E. G.; Elmi, S.

    The biostratigraphic division of the upper Bajocian-middle Callovian of South America is based on ammonites from different sections of the following provinces and regions: Neuquén, Mendoza, and San Juan in Argentina; Malleco, Linares, Talca, Atacama, Antofagasta, and Tarapacá in Chile. The complete upper Bajocian-middle Callovian succession includes the following biostratigraphic units: the Megasphaeroceras magnum assemblage zone, lowermost upper Bajocian; the Cadomites-Tulitidae mixed assemblages, (?lower) middle and upper Bathonian; the Steinmanni zone, index Lilloettia steinmanni (Spath), uppermost Bathonian, with two local horizons— Stenocephalites gerthi horizon (Argentina) and Choffatia jupiter horizon (northern Chile); the Vergarensis zone, index Eurycephalites vergarensis (Burck.), near the Bathonian-Callovian boundary; the Bodenbenderi zone, index Neuqueniceras (Frickites) bodenbenderi (Tornq.), lower Callovian; the Proximum zone, index Hecticoceras proximum Elmi, uppermost lower Callovian; and the Rehmannia (Loczyceras) patagoniensis horizon, middle Callovian.

  12. Sedimentology of the Upper Triassic-Lower Jurassic (?) Mosolotsane Formation (Karoo Supergroup), Kalahari Karoo Basin, Botswana

    Science.gov (United States)

    Bordy, Emese M.; Segwabe, Tebogo; Makuke, Bonno

    2010-08-01

    The Mosolotsane Formation (Lebung Group, Karoo Supergroup) in the Kalahari Karoo Basin of Botswana is a scantly exposed, terrestrial red bed succession which is lithologically correlated with the Late Triassic to Early Jurassic Molteno and Elliot Formations (Karoo Supergroup) in South Africa. New evidence derived from field observations and borehole data via sedimentary facies analysis allowed the assessment of the facies characteristics, distribution and thickness variation as well as palaeo-current directions and sediment composition, and resulted in the palaeo-environmental reconstruction of this poorly known unit. Our results show that the Mosolotsane Formation was deposited in a relatively low-sinuosity meandering river system that drained in a possibly semi-arid environment. Sandstone petrography revealed mainly quartz-rich arenites that were derived from a continental block provenance dominated by metamorphic and/or igneous rocks. Palaeo-flow measurements indicate reasonably strong, unidirectional current patterns with mean flow directions from southeast and east-southeast to northwest and west-northwest. Regional thickness and facies distributions as well as palaeo-drainage indicators suggest that the main depocenter of the Mosolotsane Formation was in the central part of the Kalahari Karoo Basin. Separated from this main depocenter by a west-northwest - east-southeast trending elevated area, an additional depocenter was situated in the north-northeast part of the basin and probably formed part of the Mid-Zambezi Karoo Basin. In addition, data also suggests that further northeast-southwest trending uplands probably existed in the northwest and east, the latter separating the main Kalahari Karoo depocenter from the Tuli Basin.

  13. The nature of porosity in organic-rich mudstones of the Upper Jurassic Kimmeridge Clay Formation, North Sea, offshore United Kingdom

    Science.gov (United States)

    Fishman, Neil S.; Hackley, Paul C.; Lowers, Heather; Hill, Ronald J.; Egenhoff, Sven O.; Eberl, Dennis D.; Blum, Alex E.

    2012-01-01

    Analyses of organic-rich mudstones from wells that penetrated the Upper Jurassic Kimmeridge Clay Formation, offshore United Kingdom, were performed to evaluate the nature of both organic and inorganic rock constituents and their relation to porosity in this world-class source rock. The formation is at varying levels of thermal maturity, ranging from immature in the shallowest core samples to mature in the deepest core samples. The intent of this study was to evaluate porosity as a function of both organic macerals and thermal maturity. At least four distinct types of organic macerals were observed in petrographic and SEM analyses and they all were present across the study area. The macerals include, in decreasing abundance: 1) bituminite admixed with clays; 2) elongate lamellar masses (alginite or bituminite) with small quartz, feldspar, and clay entrained within it; 3) terrestrial (vitrinite, fusinite, semifusinite) grains; and 4) Tasmanites microfossils. Although pores in all maceral types were observed on ion-milled surfaces of all samples, the pores (largely nanopores with some micropores) vary as a function of maceral type. Importantly, pores in the macerals do not vary systematically as a function of thermal maturity, insofar as organic pores are of similar size and shape in both the immature and mature Kimmeridge rocks. If any organic pores developed during the generation of hydrocarbons, they were apparently not preserved, possibly because of the highly ductile nature of much of the rock constituents of Kimmeridge mudstones (clays and organic material). Inorganic pores (largely micropores with some nanopores) have been observed in all Kimmeridge mudstones. These pores, particularly interparticle (i.e., between clay platelets), and intraparticle (i.e., in framboidal pyrite, in partially dissolved detrital K-feldspar, and in both detrital and authigenic dolomite) are noteworthy because they compose much of the observable porosity in the shales in both

  14. Litholepas klausreschi gen. et sp. nov., a new neolepadine barnacle (Cirripedia, Thoracica) on a sponge from the Upper Jurassic lithographic limestones of southern Germany

    DEFF Research Database (Denmark)

    Nagler, Christina; Haug, Joachim T.; Glenner, Henrik

    2017-01-01

    In this study we describe a unique fossil comprising 13 intact specimens of a pedunculate cirripede attached to a sponge (Codites serpentinus). The fossil comes from the Upper Jurassic lithographic limestones of southern Germany. Based on the shape and distinctive sculpture of the plates, a new...... uncertain. Representatives of L. klausreschi gen. et sp. nov. are considered to have lived either in a parasitic or commensal relationship partially buried within the sponge....

  15. Mineralization of soft-part anatomy and invading microbes in the horseshoe crab Mesolimulus from the Upper Jurassic Lagerstätte of Nusplingen, Germany.

    Science.gov (United States)

    Briggs, Derek E G; Moore, Rachel A; Shultz, Jeffrey W; Schweigert, Günter

    2005-03-22

    A remarkable specimen of Mesolimulus from the Upper Jurassic (Kimmeridgian) of Nusplingen, Germany, preserves the musculature of the prosoma and associated microbes in three dimensions in calcium phosphate (apatite). The musculature of Mesolimulus conforms closely to that of modern horseshoe crabs. Associated with the muscles are patches of mineralized biofilm with spiral and coccoid forms. This discovery emphasizes the potential of soft-bodied fossils as a source for increasing our knowledge of the diversity of fossil microbes in particular settings.

  16. Assessment of undiscovered continuous oil and gas resources of Upper Cretaceous Shales in the Songliao Basin of China, 2017

    Science.gov (United States)

    Potter, Christopher J.; Schenk, Christopher J.; Pitman, Janet K.; Klett, Timothy R.; Tennyson, Marilyn E.; Gaswirth, Stephanie B.; Leathers-Miller, Heidi M.; Finn, Thomas M.; Brownfield, Michael E.; Mercier, Tracey J.; Marra, Kristen R.; Woodall, Cheryl A.

    2018-05-03

    Using a geology-based assessment methodology, the U.S. Geological Survey estimated mean undiscovered, technically recoverable resources of 3.3 billion barrels of oil and 887 billion cubic feet of gas in shale reservoirs of the Upper Cretaceous Qingshankou and Nenjiang Formations in the Songliao Basin of northeastern China.

  17. Temporal evolution of fault systems in the Upper Jurassic of the Central German Molasse Basin: case study Unterhaching

    Science.gov (United States)

    Budach, Ingmar; Moeck, Inga; Lüschen, Ewald; Wolfgramm, Markus

    2018-03-01

    The structural evolution of faults in foreland basins is linked to a complex basin history ranging from extension to contraction and inversion tectonics. Faults in the Upper Jurassic of the German Molasse Basin, a Cenozoic Alpine foreland basin, play a significant role for geothermal exploration and are therefore imaged, interpreted and studied by 3D seismic reflection data. Beyond this applied aspect, the analysis of these seismic data help to better understand the temporal evolution of faults and respective stress fields. In 2009, a 27 km2 3D seismic reflection survey was conducted around the Unterhaching Gt 2 well, south of Munich. The main focus of this study is an in-depth analysis of a prominent v-shaped fault block structure located at the center of the 3D seismic survey. Two methods were used to study the periodic fault activity and its relative age of the detected faults: (1) horizon flattening and (2) analysis of incremental fault throws. Slip and dilation tendency analyses were conducted afterwards to determine the stresses resolved on the faults in the current stress field. Two possible kinematic models explain the structural evolution: One model assumes a left-lateral strike slip fault in a transpressional regime resulting in a positive flower structure. The other model incorporates crossing conjugate normal faults within a transtensional regime. The interpreted successive fault formation prefers the latter model. The episodic fault activity may enhance fault zone permeability hence reservoir productivity implying that the analysis of periodically active faults represents an important part in successfully targeting geothermal wells.

  18. Reservoir characterization of the Upper Jurassic geothermal target formations (Molasse Basin, Germany): role of thermofacies as exploration tool

    Science.gov (United States)

    Homuth, S.; Götz, A. E.; Sass, I.

    2015-06-01

    The Upper Jurassic carbonates of the southern German Molasse Basin are the target of numerous geothermal combined heat and power production projects since the year 2000. A production-orientated reservoir characterization is therefore of high economic interest. Outcrop analogue studies enable reservoir property prediction by determination and correlation of lithofacies-related thermo- and petrophysical parameters. A thermofacies classification of the carbonate formations serves to identify heterogeneities and production zones. The hydraulic conductivity is mainly controlled by tectonic structures and karstification, whilst the type and grade of karstification is facies related. The rock permeability has only a minor effect on the reservoir's sustainability. Physical parameters determined on oven-dried samples have to be corrected, applying reservoir transfer models to water-saturated reservoir conditions. To validate these calculated parameters, a Thermo-Triaxial-Cell simulating the temperature and pressure conditions of the reservoir is used and calorimetric and thermal conductivity measurements under elevated temperature conditions are performed. Additionally, core and cutting material from a 1600 m deep research drilling and a 4850 m (total vertical depth, measured depth: 6020 m) deep well is used to validate the reservoir property predictions. Under reservoir conditions a decrease in permeability of 2-3 magnitudes is observed due to the thermal expansion of the rock matrix. For tight carbonates the matrix permeability is temperature-controlled; the thermophysical matrix parameters are density-controlled. Density increases typically with depth and especially with higher dolomite content. Therefore, thermal conductivity increases; however the dominant factor temperature also decreases the thermal conductivity. Specific heat capacity typically increases with increasing depth and temperature. The lithofacies-related characterization and prediction of reservoir

  19. Field-scale forward modelling of a shallow marine carbonate ramp: the Upper Jurassic Arab Formation (onshore Abu Dhabi - UAE)

    Science.gov (United States)

    Marchionda, Elisabetta; Deschamps, Rémy; Nader, Fadi H.; Ceriani, Andrea; Di Giulio, Andrea; Lawrence, David; Morad, Daniel J.

    2017-04-01

    The stratigraphic record of a carbonate system is the result of the interplay of several local and global factors that control the physical and the biological responses within a basin. Conceptual models cannot be detailed enough to take into account all the processes that control the deposition of sediments. The evaluation of the key controlling parameters on the sedimentation can be investigated with the use of stratigraphic forward models, that permit dynamic and quantitative simulations of the sedimentary basin infill. This work focuses on an onshore Abu Dhabi field (UAE) and it aims to provide a complete picture of the stratigraphic evolution of Upper Jurassic Arab Formation (Fm.). In this study, we started with the definition of the field-scale conceptual depositional model of the Formation, resulting from facies and well log analysis based on five wells. The Arab Fm. could be defined as a shallow marine carbonate ramp, that ranges from outer ramp deposits to supratidal/evaporitic facies association (from bottom to top). With the reconstruction of the sequence stratigraphic pattern and several paleofacies maps, it was possible to suggest multiple directions of progradations at local scale. Then, a 3D forward modelling tool has been used to i) identify and quantify the controlling parameters on geometries and facies distribution of the Arab Fm.; ii) predict the stratigraphic architecture of the Arab Fm.; and iii) integrate and validate the conceptual model. Numerous constraints were set during the different simulations and sensitivity analyses were performed testing the carbonate production, eustatic oscillations and transport parameters. To verify the geological consistency the 3D forward modelling has been calibrated with the available control points (five wells) in terms of thickness and facies distribution.

  20. 57Fe Mössbauer analysis of the Upper Triassic-Lower Jurassic deep-sea chert: Paleo-redox history across the Triassic-Jurassic boundary and the Toarcian oceanic anoxic event

    International Nuclear Information System (INIS)

    Sato, Tomohiko; Isozaki, Yukio; Shozugawa, Katsumi; Seimiya, Kimiko; Matsuo, Motoyuki

    2012-01-01

    We investigated the paleo-redox change across the Triassic-Jurassic (T-J) boundary (∼200 Ma) and the Early Toarcian oceanic anoxic event (T-OAE; ∼183 Ma) recorded in the Upper Triassic to Lower Jurassic pelagic deep-sea cherts in the Inuyama area, Central Japan. The present 57 Fe Mössbauer spectroscopic analysis for these cherts identified five iron species, i.e., hematite (α-Fe 2 O 3 ), pyrite (FeS 2 ), paramagnetic Fe 3 +  , and two paramagnetic Fe 2 +  with different quadrupole splittings. The occurrence of hematite and pyrite in deep-sea cherts essentially indicates primary oxidizing and reducing depositional conditions, respectively. The results confirmed that oxidizing conditions persisted in deep-sea across the T-J boundary. In contrast, across the T-OAE, deep-sea environment shifted to reducing conditions. The first appearance of the gray pyrite-bearing chert marked the onset of the deep-sea oxygen-depletion in the middle Pliensbachian, i.e., clearly before the shallow-sea T-OAE.

  1. Microbially-induced Fe and Mn oxides in condensed pelagic sediments (Middle-Upper Jurassic, Western Sicily)

    Science.gov (United States)

    Préat, A.; Mamet, B.; Di Stefano, P.; Martire, L.; Kolo, K.

    2011-06-01

    This article presents a petrographic comparison of the Rosso Ammonitico facies of Western Sicily and the original Rosso Ammonitico Veronese of Northern Italy based on a total of 27 sections. The Rosso Ammonitico has been the subject of numerous controversies that range from bathyal to shallow-water platform sedimentation. Therefore it seemed interesting to verify if the term Rosso Ammonitico has the same geologic connotation from region to region. The Middle-Upper Jurassic Rosso Ammonitico of Western Sicily is a condensed succession formed during a period of extensional synsedimentary tectonics related to the spreading of the Ionian Ocean. Slope-to-basin or pelagic carbonate deposits characterize the sedimentation which consists of reddish mudstones and wackestones. The abundant fauna is composed of radiolarians, protoglobigerinids, Saccocoma, Bositra associated with ammonites. A few ferruginous hardgrounds, Fe-Mn oxide crusts and Mn-coated condensation horizons are also present. The red matrices contain abundant Fe-Mn encrusted, microbored and bioeroded bioclasts. Sporadic Fe-Mn oncolites composed of amorphous Mn-minerals and goethite are also conspicuous. The matrix, as well as the shells and the fillings of the complex associated veinlets, are frequently altered into calcite microsparite. Submicronic iron bacterial and fungal filaments associated with mineralized extracellular polymeric substances (EPS) are observed in the matrix. They record dysaerobic microenvironments at or near the sediment-water interfaces. Early mineralized discontinuities enhanced by subsequent pressure dissolution are reported in the succession. Mn-(Ni) bacterial filaments are exceptionally observed in the cortex of the Fe-Mn oncolites. As a consequence of an early lithification, the Mn filaments are poorly preserved. The pigmentation of the rock is due to the dispersion of submicronic oxyhydroxides (now goethite and amorphous iron) formed by bacterial mediation during early diagenesis

  2. Regional paleohydrologic and paleoclimatic settings of wetland/lacustrine depositional systems in the Morrison Formation (Upper Jurassic), Western Interior, USA

    Science.gov (United States)

    Dunagan, S.P.; Turner, C.E.

    2004-01-01

    During deposition of the Upper Jurassic Morrison Formation, water that originated as precipitation in uplands to the west of the Western Interior depositional basin infiltrated regional aquifers that underlay the basin. This regional groundwater system delivered water into the otherwise dry continental interior basin where it discharged to form two major wetland/lacustrine successions. A freshwater carbonate wetland/lacustrine succession formed in the distal reaches of the basin, where regional groundwater discharged into the Denver-Julesburg Basin, which was a smaller structural basin within the more extensive Western Interior depositional basin. An alkaline-saline wetland/lacustrine complex (Lake T'oo'dichi') formed farther upstream, where shallower aquifers discharged into the San Juan/Paradox Basin, which was another small structural basin in the Western Interior depositional basin. These were both wetlands in the sense that groundwater was the major source of water. Input from surface and meteoric water was limited. In both basins, lacustrine conditions developed during episodes of increased input of surface water. Inclusion of wetlands in our interpretation of what had previously been considered largely lacustrine systems has important implications for paleohydrology and paleoclimatology. The distal carbonate wetland/lacustrine deposits are well developed in the Morrison Formation of east-central Colorado, occupying a stratigraphic interval that is equivalent to the "lower" Morrison but extends into the "upper" Morrison Formation. Sedimentologic, paleontologic, and isotopic evidence indicate that regional groundwater discharge maintained shallow, hydrologically open, well oxygenated, perennial carbonate wetlands and lakes despite the semi-arid climate. Wetland deposits include charophyte-rich wackestone and green mudstone. Lacustrine episodes, in which surface water input was significant, were times of carbonate and siliciclastic deposition in scarce deltaic

  3. The Jurassic of Denmark and Greenland: Sedimentology and sequence stratigraphy of paralic and shallow marine Upper Jurassic sandstones in the northern Danish Central Graben

    Directory of Open Access Journals (Sweden)

    Johannessen, Peter N.

    2003-10-01

    Full Text Available Paralic and shallow marine sandstones were deposited in the Danish Central Graben during Late Jurassic rifting when half-grabens were developed and the overall eustatic sea level rose. During the Kimmeridgian, an extensive plateau area consisting of the Heno Plateau and the Gertrud Plateau was situated between two highs, the Mandal High to the north, and the combined Inge and Mads Highs to the west. These highs were land areas situated on either side of the plateaus and supplied sand to the Gertrud and Heno Plateaus. Two graben areas, the Feda and Tail End Grabens, flanked the plateau area to the west and east, respectively. The regressive–ransgressive succession consists of intensely bioturbated shoreface sandstones, 25–75 m thick. Two widespread unconformities (SB1, SB2 are recognised on the plateaus, forming the base of sequence 1 and sequence 2, respectively. These unconformities were created by a fall in relative sea level during which rivers may have eroded older shoreface sands and transported sediment across the Heno andGertrud Plateaus, resulting in the accumulation of shoreface sandstones farther out in the Feda and Tail End Grabens, on the south-east Heno Plateau and in the Salt Dome Province. Duringsubsequent transgression, fluvial sediments were reworked by high-energy shoreface processes on the Heno and Gertrud Plateaus, leaving only a lag of granules and pebbles on the marine transgressive surfaces of erosion (MTSE1, MTSE2.The sequence boundary SB1 can be traced to the south-east Heno Plateau and the Salt Dome Province, where it is marked by sharp-based shoreface sandstones. During low sea level, erosion occurred in the southern part of the Feda Graben, which formed part of the Gertrud and Heno Plateaus, and sedimentation occurred in the Norwegian part of the Feda Graben farther to the north. During subsequent transgression, the southern part of the Feda Graben began to subside, and a succession of backstepping back

  4. Lower limits of ornithischian dinosaur body size inferred from a new Upper Jurassic heterodontosaurid from North America

    Science.gov (United States)

    Butler, Richard J.; Galton, Peter M.; Porro, Laura B.; Chiappe, Luis M.; Henderson, Donald M.; Erickson, Gregory M.

    2010-01-01

    The extremes of dinosaur body size have long fascinated scientists. The smallest (dinosaurs are carnivorous saurischian theropods, and similarly diminutive herbivorous or omnivorous ornithischians (the other major group of dinosaurs) are unknown. We report a new ornithischian dinosaur, Fruitadens haagarorum, from the Late Jurassic of western North America that rivals the smallest theropods in size. The largest specimens of Fruitadens represent young adults in their fifth year of development and are estimated at just 65–75 cm in total body length and 0.5–0.75 kg body mass. They are thus the smallest known ornithischians. Fruitadens is a late-surviving member of the basal dinosaur clade Heterodontosauridae, and is the first member of this clade to be described from North America. The craniodental anatomy and diminutive body size of Fruitadens suggest that this taxon was an ecological generalist with an omnivorous diet, thus providing new insights into morphological and palaeoecological diversity within Dinosauria. Late-surviving (Late Jurassic and Early Cretaceous) heterodontosaurids are smaller and less ecologically specialized than Early (Late Triassic and Early Jurassic) heterodontosaurids, and this ecological generalization may account in part for the remarkable 100-million-year-long longevity of the clade. PMID:19846460

  5. Biozonation of the furongian (upper Cambrian) alum shale formation at Hunneberg, Sweden

    DEFF Research Database (Denmark)

    Rasmussen, Bo Wilhelm; Rasmussen, Jan Audun Liljeroth; Nielsen, Arne Thorshøj

    2016-01-01

    The Furongian Alum Shale at Nygård, Hunneberg, Sweden, has been sampled for trilobites. The section is ≥12.20 m thick and comprises a relatively thick Olenus superzone, overlain by more condensed Parabolina, Leptoplastus, Protopeltura and Peltura superzones. The section is truncated low in the Pe......The Furongian Alum Shale at Nygård, Hunneberg, Sweden, has been sampled for trilobites. The section is ≥12.20 m thick and comprises a relatively thick Olenus superzone, overlain by more condensed Parabolina, Leptoplastus, Protopeltura and Peltura superzones. The section is truncated low...

  6. Germanium and uranium in coalified wood from upper Devonian black shale

    Energy Technology Data Exchange (ETDEWEB)

    Breger, I A; Schopf, J M

    1955-02-01

    Spectrographic analyses were performed on carbonaceous material and shale samples from the Chattanooga shale in Tennessee and the Cleveland member of the Ohio shale in Ohio with particular emphasis on U and Ge. Semiquantitative analyses for 29 elements (Fe, Si, Ge, Al, Ca, V, Ni, U, Mg, Cu, Ti, Cr, Mo, Na, Sr, B, Y, Pb, Ba, Co, Sn, Zr, Mn, Zn, Yb, Ga, Sc, Be) were performed on both ash specimens and whole sample. The analyses showed unusually high percentages of Ge (1 to 5%) U (0.1 to 1%), V (1 to 5%), and Ni (0.1 to 1%) in the ash of coal from the Chattanooga and Ohio shales. Quantitative chemical analysis for U, Ge, V, and Ni in the whole coal and ash were done to check the results of the semiquantitative analyses. Ash content from the proximate analyses indicated that the coal samples tested were similar to vitrain in ash percentage. Because of the unusually high percentages of U and Ge and the low ash of the coals tested, the author felt that the U and Ge might be associated wire also observed with lower radiation doses (200 and 400 rad).

  7. CARBONATE FACIES ZONATION OF THE UPPER JURASSIC-LOWER CRETACEOUS APULIA PLATFORM MARGIN (GARGANO PROMONTORY, SOUTHERN ITALY

    Directory of Open Access Journals (Sweden)

    MICHELE MORSILLI

    1997-07-01

    Full Text Available The Late Jurassic-Early Cretaceous Apulia platform margin and the transition to adjacent basinal deposits (inner platform to basin are well exposed in the Gargano Promontory. Detailed field work has allowed to recognize eight main facies associations which reflect various depositional environments, and which document a differentiated zonation, from the inner platform to the basin. A shallow lagoon existed in the internal part of the Gargano Promontory with a transition to tidal flat areas (F1. Oolitic shoals (F2 bordered this internal peritidal area passing seaward to a reef-flat with abundant corals (F3. A reef-front, associated with a coral rubble zone, has been found in some areas (F4. In the external margin zone, massive wackestones with Ellipsactinia occur (F5 and pass gradually to a rudstone facies on the proximal slope (F6. The base-of-slope facies association consists of pelagic sediments interbedded with gravity-displaced deposits (F7 and F8. The depositional profile of the Apulia Platform is typical of the Tethyan Jurassic-Early Cretaceous platforms, with slope declivities in the order of 25°-28°. The remarkable progradation of the platform in the northern tract of the Gargano (Lesina and Varano lakes area and its substantial stability east- and southwards (Mattinata area suggest a possible windward position of the margin in this latter portion and, in contrast, a leeward position of the northern portion.   

  8. Characterization of lacustrine shale pore structure: The Upper-Triassic Yanchang Formation, Ordos Basin, China

    Directory of Open Access Journals (Sweden)

    Yuxi Yu

    2016-08-01

    Full Text Available Amounts of silty laminae in continental shale gas reservoir were investigated in the Zhangjiatan shale of the Yanchang Formation, Ordos Basin. The purpose of this study is to provide awareness in terms of the nature and discrepancies in pore structure between silty laminae and clayey laminae. By mechanically separating the silty laminae from the shale core, a combination measurement series of mercury injection capillary pressure, N2 adsorption, and carbon dioxide adsorption were performed on the aforementioned two parts. An integrated pore size distribution, with a pore diameter range of 0.1 nm-100 μm, was obtained by using appropriate sample particle size and calculation model. The comparative analysis of the pore structure shows that the clayey laminae are dominated by mesopore and micropore; meanwhile, the silty laminae are dominated by macropore alone. The pore volume distribution in clayey laminae is sorted as mesopore volume > micropore volume > macropore volume, on the other hand, for silty laminae it is macropore volume > mesopore volume > micropore volume. The averaged total pore volume of silty laminae is 2.02 cc/100 g, and for clayey laminae, it is 1.41 cc/100 g. The porosity of silty laminae is 5.40%, which is greater than that of clayey laminae's 3.67%. Since silty laminae have larger pore width and pore space, they are more permeable and porous than the clayey laminae; it also acts as a favorable conduit and reservoir for shale gas.

  9. Paleogeographic and paleo-oceanographic influences on carbon isotope signatures: Implications for global and regional correlation, Middle-Upper Jurassic of Saudi Arabia

    Science.gov (United States)

    Eltom, Hassan A.; Gonzalez, Luis A.; Hasiotis, Stephen T.; Rankey, Eugene C.; Cantrell, Dave L.

    2018-02-01

    Carbon isotope data (δ13C) can provide an essential means for refining paleogeographic and paleo-oceanographic reconstructions, and interpreting stratigraphic architecture within complex carbonate strata. Although the primary controls on global δ13C signatures of marine carbonates are well understood, understanding their latitudinal and regional variability is poor. To better constrain the nature and applications of δ13C stratigraphy, this study: 1) presents a new high-resolution δ13C stratigraphic curve from Middle to Upper Jurassic carbonates in the upper Tuwaiq Mountain, Hanifa, and lower Jubaila formations in central Saudi Arabia; 2) explores their latitudinal and regional variability; and 3) discusses their implications for stratigraphic correlations. Analysis of δ13C data identified six mappable units with distinct δ13C signatures (units 1-6) between up-dip and down-dip sections, and one unit (unit 7) that occurs only in the down-dip section of the study succession. δ13C data from the upper Tuwaiq Mountain Formation and the lower Hanifa Formation (units 1, 2), which represent Upper Callovian to Middle Oxfordian strata, and record two broad positive δ13C excursions. In the upper part of the Hanifa Formation (units 3-6, Early Oxfordian-Late Kimmeridgian), δ13C values decreased upward to unit 7, which showed a broad positive δ13C excursion. Isotopic data suggest similar δ13C trends between the southern margin of the Tethys Ocean (Arabian Plate; low latitude, represented by the study succession) and northern Tethys oceans (high latitude), despite variations in paleoclimatic, paleogeographic, and paleoceanographic conditions. Variations in the δ13C signal in this succession can be attributed to the burial of organic matter and marine circulation at the time of deposition. Our study uses δ13C signatures to provide independent data for chronostratigraphic constraints which help in stratigraphic correlations within heterogeneous carbonate successions.

  10. Characterising the vertical separation of shale-gas source rocks and aquifers across England and Wales (UK)

    Science.gov (United States)

    Loveless, Sian E.; Bloomfield, John P.; Ward, Robert S.; Hart, Alwyn J.; Davey, Ian R.; Lewis, Melinda A.

    2018-03-01

    Shale gas is considered by many to have the potential to provide the UK with greater energy security, economic growth and jobs. However, development of a shale gas industry is highly contentious due to environmental concerns including the risk of groundwater pollution. Evidence suggests that the vertical separation between exploited shale units and aquifers is an important factor in the risk to groundwater from shale gas exploitation. A methodology is presented to assess the vertical separation between different pairs of aquifers and shales that are present across England and Wales. The application of the method is then demonstrated for two of these pairs—the Cretaceous Chalk Group aquifer and the Upper Jurassic Kimmeridge Clay Formation, and the Triassic sandstone aquifer and the Carboniferous Bowland Shale Formation. Challenges in defining what might be considered criteria for `safe separation' between a shale gas formation and an overlying aquifer are discussed, in particular with respect to uncertainties in geological properties, aquifer extents and determination of socially acceptable risk levels. Modelled vertical separations suggest that the risk of aquifer contamination from shale exploration will vary greatly between shale-aquifer pairs and between regions and this will need to be considered carefully as part of the risk assessment and management for any shale gas development.

  11. Gas chromatograph study of bitumen from oil shale of Amman Formation (upper cretaceous), NW Jordan

    International Nuclear Information System (INIS)

    Darwish, H.; Mustafa, H.

    1997-01-01

    The extractable organic matter of seven outcrop samples of Amman Formation Oil Shale have been analysed by Gas Chromatography (GC). The bitumen is rich in heterocompounds contents (> 60 wt%). Gas chromatograms show a predominance of iosprenoids, specially phytane over n-alkanes, and low carbon preference index (CPI). This indicates that the organic matter is immature, and its origin is mainly of marine organisms. These rocks could be possible source rocks due to the high content of hydrocarbon. (authors). 22 refs., 4 figs. 3 tabs

  12. Age and microfacies of oceanic Upper Triassic radiolarite components from the Middle Jurassic ophiolitic mélange in the Zlatibor Mountains (Inner Dinarides, Serbia and their provenance

    Directory of Open Access Journals (Sweden)

    Gawlick Hans-Jürgen

    2017-08-01

    Full Text Available Oceanic radiolarite components from the Middle Jurassic ophiolitic mélange between Trnava and Rožanstvo in the Zlatibor Mountains (Dinaridic Ophiolite Belt west of the Drina–Ivanjica unit yield Late Triassic radiolarian ages. The microfacies characteristics of the radiolarites show pure ribbon radiolarites without crinoids or thin-shelled bivalves. Beside their age and the preservation of the radiolarians this points to a deposition of the radiolarites on top of the oceanic crust of the Neo-Tethys, which started to open in the Late Anisian. South of the study area the ophiolitic mélange (Gostilje–Ljubiš–Visoka–Radoševo mélange contains a mixture of blocks of 1 oceanic crust, 2 Middle and Upper Triassic ribbon radiolarites, and 3 open marine limestones from the continental slope. On the basis of this composition we can conclude that the Upper Triassic radiolarite clasts derive either from 1 the younger parts of the sedimentary succession above the oceanic crust near the continental slope or, more convincingly 2 the sedimentary cover of ophiolites in a higher nappe position, because Upper Triassic ribbon radiolarites are only expected in more distal oceanic areas. The ophiolitic mélange in the study area overlies different carbonate blocks of an underlying carbonate-clastic mélange (Sirogojno mélange. We date and describe three localities with different Upper Triassic radiolarite clasts in a mélange, which occurs A on top of Upper Triassic fore-reef to reefal limestones (Dachstein reef, B between an Upper Triassic reefal limestone block and a Lower Carnian reef limestone (Wetterstein reef, and C in fissures of an Upper Triassic lagoonal to back-reef limestone (Dachstein lagoon. The sedimentary features point to a sedimentary and not to a tectonic emplacement of the ophiolitic mélange (= sedimentary mélange filling the rough topography of the topmost carbonate-clastic mélange below. The block spectrum of the underlying and

  13. Age and microfacies of oceanic Upper Triassic radiolarite components from the Middle Jurassic ophiolitic mélange in the Zlatibor Mountains (Inner Dinarides, Serbia) and their provenance

    Science.gov (United States)

    Gawlick, Hans-Jürgen; Djerić, Nevenka; Missoni, Sigrid; Bragin, Nikita Yu.; Lein, Richard; Sudar, Milan; Jovanović, Divna

    2017-08-01

    Oceanic radiolarite components from the Middle Jurassic ophiolitic mélange between Trnava and Rožanstvo in the Zlatibor Mountains (Dinaridic Ophiolite Belt) west of the Drina-Ivanjica unit yield Late Triassic radiolarian ages. The microfacies characteristics of the radiolarites show pure ribbon radiolarites without crinoids or thin-shelled bivalves. Beside their age and the preservation of the radiolarians this points to a deposition of the radiolarites on top of the oceanic crust of the Neo-Tethys, which started to open in the Late Anisian. South of the study area the ophiolitic mélange (Gostilje-Ljubiš-Visoka-Radoševo mélange) contains a mixture of blocks of 1) oceanic crust, 2) Middle and Upper Triassic ribbon radiolarites, and 3) open marine limestones from the continental slope. On the basis of this composition we can conclude that the Upper Triassic radiolarite clasts derive either from 1) the younger parts of the sedimentary succession above the oceanic crust near the continental slope or, more convincingly 2) the sedimentary cover of ophiolites in a higher nappe position, because Upper Triassic ribbon radiolarites are only expected in more distal oceanic areas. The ophiolitic mélange in the study area overlies different carbonate blocks of an underlying carbonate-clastic mélange (Sirogojno mélange). We date and describe three localities with different Upper Triassic radiolarite clasts in a mélange, which occurs A) on top of Upper Triassic fore-reef to reefal limestones (Dachstein reef), B) between an Upper Triassic reefal limestone block and a Lower Carnian reef limestone (Wetterstein reef), and C) in fissures of an Upper Triassic lagoonal to back-reef limestone (Dachstein lagoon). The sedimentary features point to a sedimentary and not to a tectonic emplacement of the ophiolitic mélange (= sedimentary mélange) filling the rough topography of the topmost carbonate-clastic mélange below. The block spectrum of the underlying and slightly older

  14. Anatomy and Cranial Functional Morphology of the Small-Bodied Dinosaur Fruitadens haagarorum from the Upper Jurassic of the USA

    Science.gov (United States)

    Butler, Richard J.; Porro, Laura B.; Galton, Peter M.; Chiappe, Luis M.

    2012-01-01

    Background Heterodontosaurids are an important but enigmatic and poorly understood early radiation of ornithischian dinosaurs. The late-surviving heterodontosaurid Fruitadens haagarorum from the Late Jurassic (early Tithonian) Morrison Formation of the western USA is represented by remains of several small (dinosaurs. Methodology/Principal Findings We describe the cranial and postcranial anatomy of Fruitadens in detail, providing comparisons to all other known heterodontosaurid taxa. High resolution micro-CT data provides new insights into tooth replacement and the internal anatomy of the tooth-bearing bones. Moreover, we provide a preliminary functional analysis of the skull of late-surviving heterodontosaurids, discuss the implications of Fruitadens for current understanding of heterodontosaurid monophyly, and briefly review the evolution and biogeography of heterodontosaurids. Conclusions/Significance The validity of Fruitadens is supported by multiple unique characters of the dentition and hindlimb as well as a distinct character combination. Fruitadens shares highly distinctive appendicular characters with other heterodontosaurids, strengthening monophyly of the clade on the basis of the postcranium. Mandibular morphology and muscle moment arms suggest that the jaws of late-surviving heterodontosaurids, including Fruitadens, were adapted for rapid biting at large gape angles, contrasting with the jaws of the stratigraphically older Heterodontosaurus, which were better suited for strong jaw adduction at small gapes. The lack of wear facets and plesiomorphic dentition suggest that Fruitadens used orthal jaw movements and employed simple puncture-crushing to process food. In combination with its small body size, these results suggest that Fruitadens was an ecological generalist, consuming select plant material and possibly insects or other invertebrates. PMID:22509242

  15. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2002-09-25

    The University of Alabama in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company are undertaking an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary objective of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. The principal research effort for Year 2 of the project has been reservoir characterization, 3-D modeling and technology transfer. This effort has included six tasks: (1) the study of rockfluid interactions, (2) petrophysical and engineering characterization, (3) data integration, (4) 3-D geologic modeling, (5) 3-D reservoir simulation and (6) technology transfer. This work was scheduled for completion in Year 2. Overall, the project work is on schedule. Geoscientific reservoir characterization is essentially completed. The architecture, porosity types and heterogeneity of the reef and shoal reservoirs at Appleton and Vocation Fields have been characterized using geological and geophysical data. The study of rock-fluid interactions is near completion. Observations regarding the diagenetic processes influencing pore system development and

  16. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2001-09-14

    The University of Alabama in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company are undertaking an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary objective of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. The principal research effort for Year 1 of the project has been reservoir description and characterization. This effort has included four tasks: (1) geoscientific reservoir characterization, (2) the study of rock-fluid interactions, (3) petrophysical and engineering characterization and (4) data integration. This work was scheduled for completion in Year 1. Overall, the project work is on schedule. Geoscientific reservoir characterization is essentially completed. The architecture, porosity types and heterogeneity of the reef and shoal reservoirs at Appleton and Vocation Fields have been characterized using geological and geophysical data. The study of rock-fluid interactions has been initiated. Observations regarding the diagenetic processes influencing pore system development and heterogeneity in these reef and shoal reservoirs have been

  17. IMPROVED OIL RECOVERY FROM UPPER JURASSIC SMACKOVER CARBONATES THROUGH THE APPLICATION OF ADVANCED TECHNOLOGIES AT WOMACK HILL OIL FIELD, CHOCTAW AND CLARKE COUNTIES, EASTERN GULF COASTAL PLAIN

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2003-05-20

    Pruet Production Co. and the Center for Sedimentary Basin Studies at the University of Alabama, in cooperation with Texas A&M University, Mississippi State University, University of Mississippi, and Wayne Stafford and Associates are undertaking a focused, comprehensive, integrated and multidisciplinary study of Upper Jurassic Smackover carbonates (Class II Reservoir), involving reservoir characterization and 3-D modeling and an integrated field demonstration project at Womack Hill Oil Field Unit, Choctaw and Clarke Counties, Alabama, Eastern Gulf Coastal Plain. The principal objectives of the project are: increasing the productivity and profitability of the Womack Hill Field Unit, thereby extending the economic life of this Class II Reservoir and transferring effectively and in a timely manner the knowledge gained and technology developed from this project to producers who are operating other domestic fields with Class II Reservoirs. The principal research efforts for Year 3 of the project have been recovery technology analysis and recovery technology evaluation. The research focus has primarily been on well test analysis, 3-D reservoir simulation, microbial core experiments, and the decision to acquire new seismic data for the Womack Hill Field area. Although Geoscientific Reservoir Characterization and 3-D Geologic Modeling have been completed and Petrophysical and Engineering Characterization and Microbial Characterization are essentially on schedule, a no-cost extension until September 30, 2003, has been granted by DOE so that new seismic data for the Womack Hill Field can be acquired and interpreted to assist in the determination as to whether Phase II of the project should be implemented.

  18. Sedimentology and palaeontology of the Upper Jurassic Puesto Almada Member (Cañadón Asfalto Formation, Fossati sub-basin), Patagonia Argentina: Palaeoenvironmental and climatic significance

    Science.gov (United States)

    Cabaleri, Nora G.; Benavente, Cecilia A.; Monferran, Mateo D.; Narváez, Paula L.; Volkheimer, Wolfgang; Gallego, Oscar F.; Do Campo, Margarita D.

    2013-10-01

    Six facies associations are described for the Puesto Almada Member at the Cerro Bandera locality (Fossati sub-basin). They correspond to lacustrine, palustrine, and pedogenic deposits (limestones); and subordinated alluvial fan, fluvial, aeolian, and pyroclastic deposits. The lacustrine-palustrine depositional setting consisted of carbonate alkaline shallow lakes surrounded by flooded areas in a low-lying topography. The facies associations constitute four shallowing upward successions defined by local exposure surfaces: 1) a Lacustrine-Palustrine-pedogenic facies association with a 'conchostracan'-ostracod association; 2) a Palustrine facies association representing a wetland subenvironment, and yielding 'conchostracans', body remains of insects, fish scales, ichnofossils, and palynomorphs (cheirolepidiacean species and ferns growing around water bodies, and other gymnosperms in more elevated areas); 3) an Alluvial fan facies association indicating the source of sediment supply; and 4) a Lacustrine facies association representing a second wetland episode, and yielding 'conchostracans', insect ichnofossils, and a palynoflora mainly consisting of planktonic green algae associated with hygrophile elements. The invertebrate fossil assemblage found contains the first record of fossil insect bodies (Insecta-Hemiptera and Coleoptera) for the Cañadón Asfalto Formation. The succession reflects a mainly climatic control over sedimentation. The sedimentary features of the Puesto Almada Member are in accordance with an arid climatic scenario across the Upper Jurassic, and they reflect a strong seasonality with periods of higher humidity represented by wetlands and lacustrine sediments.

  19. Petrogenesis and origin of the Upper Jurassic-Lower Cretaceous magmatism in Central High Atlas (Morocco): Major, trace element and isotopic (Sr-Nd) constraints

    Science.gov (United States)

    Essaifi, Abderrahim; Zayane, Rachid

    2018-01-01

    During an uplift phase, which lasted ca. 40 Ma, from the Late Jurassic (165 Ma) to the Early Cretaceous (125 Ma), transitional to moderately alkaline magmatic series were emplaced in the Central High Atlas. The corresponding magmatic products include basaltic lava flows erupted within wide synclines and intrusive complexes composed of layered mafic intrusions and monzonitic to syenitic dykes emplaced along narrow anticlinal ridges. The igneous rock sequence within the intrusive complexes is composed of troctolites, olivine-gabbros, oxide-gabbros, monzonites and syenites. The chemical compositions of the various intrusive rocks can be accounted for by crystal accumulation, fractional crystallization and post-magmatic remobilization. The evolution from the troctolites to the syenites was mainly controlled by a fractional crystallization process marked by early fractionation of olivine, plagioclase and clinopyroxene, followed by separation of biotite, amphibole, apatite, and Ti-magnetite. Hydrothermal activity associated with emplacement of the intrusions within the Jurassic limestones modified the elemental and the Sr isotopic composition of the hydrothermally altered rocks In particular the monzonitic to syenitic dykes underwent an alkali metasomatism marked by depletion in K and Rb and enrichment in Na and Sr. As a result, their Sr isotopic composition was shifted towards higher initial Sr isotopic ratios (0.7067-0.7075) with respect to the associated gabbros (0.7036-0.7046). On the contrary, the Nd isotopic compositions were preserved from isotope exchange with the limestones and vary in a similar range to those of the gabbros (+1.6 < εNdi < +4.1). The isotopic and the trace element ratios of the uncontaminated samples were used to constrain the source characteristics of this magmatism. The Sr-Nd isotopic data and the incompatible element ratios (e.g. La/Nb, Zr/Nb, Th/U, Ce/Pb) are consistent with generation from an enriched upper mantle similar to an ocean

  20. Thermal evolution and shale gas potential estimation of the Wealden and Posidonia Shale in NW-Germany and the Netherlands : a 3D basin modelling study

    NARCIS (Netherlands)

    Bruns, B.; Littke, R.; Gasparik, M.; van Wees, J.-D.; Nelskamp, S.

    Sedimentary basins in NW-Germany and the Netherlands represent potential targets for shale gas exploration in Europe due to the presence of Cretaceous (Wealden) and Jurassic (Posidonia) marlstones/shales as well as various Carboniferous black shales. In order to assess the regional shale gas

  1. Petrotectonic characteristics, geochemistry, and U-Pb geochronology of Jurassic plutons in the Upper Magdalena Valley-Colombia: Implications on the evolution of magmatic arcs in the NW Andes

    Science.gov (United States)

    Rodríguez, G.; Arango, M. I.; Zapata, G.; Bermúdez, J. G.

    2018-01-01

    Field, petrographic, and geochemical characterization along with U-Pb zircon geochronology of the Jurassic plutons exposed in the Upper Magdalena Valley (Colombia) allowed recognizing distinct western and eastern suites formed in at least three magmatic pulses. The western plutons crop out between the eastern flank of the Central Cordillera and the Las Minas range, being limited by the Avirama and the Betania-El Agrado faults. The western suite comprises a quartz monzonite - quartz monzodiorite - quartz diorite series and subordinate monzogranites. Chemically, the rocks are high-K calc-alkaline I-type granitoids (some reaching the shoshonitic series) with metaluminous of magnesium affinity. Trace-element tectonic discrimination is consistent with magmatism in a continental arc environment. Most rocks of this suite crystallized between 195 and 186 Ma (Early Jurassic, Pliensbachian), but locally some plutons yielded younger ages between 182 and 179 Ma (Early Jurassic, Toarcian). The eastern suite crops out in the eastern margin of the Upper Magdalena Valley, east of the Betania - El Agrado fault. Plutons of this unit belong to the monzogranite series with rock types ranging between syenogranites and granodiorites. They are high-K calc-alkaline continental granitoids, some metaluminous and some peraluminous, related to I-type granites generated in a volcanic arc. Crystallization of the suite was between 173 and 169 Ma (Middle Jurassic, Aalenian-Bajocian), but locally these rocks contain zircon with earlier inherited ages related to the magmatic pulse of the western suite between 182 and 179 Ma (Early Jurassic, Toarcian). The evolution of the Jurassic plutons in the Upper Magdalena Valley is best explained by onset or increase in subduction erosion of the accretionary prism. This explains the eastward migration of the arc away from the trench. Subduction of prism sediments increased the water flux from the subducting slab, decreasing solidus temperatures, therefore

  2. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2004-02-25

    The University of Alabama, in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company, has undertaken an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary goal of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. Geoscientific reservoir property, geophysical seismic attribute, petrophysical property, and engineering property characterization has shown that reef (thrombolite) and shoal reservoir lithofacies developed on the flanks of high-relief crystalline basement paleohighs (Vocation Field example) and on the crest and flanks of low-relief crystalline basement paleohighs (Appleton Field example). The reef thrombolite lithofacies have higher reservoir quality than the shoal lithofacies due to overall higher permeabilities and greater interconnectivity. Thrombolite dolostone flow units, which are dominated by dolomite intercrystalline and vuggy pores, are characterized by a pore system comprised of a higher percentage of large-sized pores and larger pore throats. Rock-fluid interactions (diagenesis) studies have shown that although the primary control on

  3. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2003-09-25

    The University of Alabama in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company are undertaking an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling that utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary objective of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. The principal research effort for Year 3 of the project has been reservoir characterization, 3-D modeling, testing of the geologic-engineering model, and technology transfer. This effort has included six tasks: (1) the study of seismic attributes, (2) petrophysical characterization, (3) data integration, (4) the building of the geologic-engineering model, (5) the testing of the geologic-engineering model and (6) technology transfer. This work was scheduled for completion in Year 3. Progress on the project is as follows: geoscientific reservoir characterization is completed. The architecture, porosity types and heterogeneity of the reef and shoal reservoirs at Appleton and Vocation Fields have been characterized using geological and geophysical data. The study of rock-fluid interactions has been completed. Observations regarding the diagenetic

  4. The taphonomy of dinosaurs from the Upper Jurassic of Tendaguru (Tanzania based on field sketches of the German tendaguru expedition (1909–1913

    Directory of Open Access Journals (Sweden)

    W.-D. Heinrich

    1999-01-01

    Full Text Available Tendaguru is one of the most important dinosaur localities in Africa. The Tendaguru Beds have produced a diverse Late Jurassic (Kimmeridgian to Tithonian dinosaur assemblage, including sauropods (Brachiosaurus, Barosaurus, Dicraeosaurus, Janenschia, theropods (e.g., Elaphrosaurus, Ceratosaurus, Allosaurus, and ornithischians (Kentrosaurus, Dryosaurus. Contrary to the well studied skeletal anatomy of the Tendaguru dinosaurs, the available taphonomic information is rather limited, and a generally accepted taphonomic model has not yet been established. Assessment of unpublished excavation sketches by the German Tendaguru expedition (1909–1913 document bone assemblages of sauropod and ornithischian dinosaurs from the Middle Saurian Bed, Upper Saurian Bed, and the Transitional Sands above the Trigonia smeei Bed, and shed some light on the taphonomy of the Tendaguru dinosaurs. Stages of disarticulation range from incomplete skeletons to solitary bones, and strongly argue for carcass decay and post-mortem transport prior to burial. The sauropod bone accumulations are dominated by adult individuals, and juveniles are rare or missing. The occurrence of bones in different superimposed dinosaur-bearing horizons indicates that skeletal remains were accumulated over a long time span during the Late Jurassic, and the majority of the bone accumulations are probably attritional. These accumulations are likely to have resulted from long-term bone imput due to normal mortality events caused by starvation, seasonal drought, disease, old age and weakness. The depositional environment of the Middle and Upper Saurian Bed was mainly limnic to brackish in origin, while the palaeoenvironment of the Transitional Sands was marginal marine. Tendaguru zählt zu den bedeutendsten Dinosaurier-Lagerstätten Afrikas. Aus den Tendaguru-Schichten sind zahlreiche Skelettreste von Sauropoden (Brachiosaurus, Barosaurus, Dicraeosaurus, Janenschia, Theropoden (z.B. Elaphrosaurus

  5. Effect of pore structure on the seepage characteristics of tight sandstone reservoirs: A case study of Upper Jurassic Penglaizhen Fm reservoirs in the western Sichuan Basin

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    Liqiang Sima

    2017-01-01

    Full Text Available Tight sandstone reservoirs are characterized by complex pore structures and strong heterogeneity, and their seepage characteristics are much different from those of conventional sandstone reservoirs. In this paper, the tight sandstone reservoirs of Upper Jurassic Penglaizhen Fm in western Sichuan Basin were analyzed in terms of their pore structures by using the data about physical property, mercury injection and nuclear magnetic resonance (NMR tests. Then, the seepage characteristics and the gas–water two-phase migration mechanisms and distribution of tight sandstone reservoirs with different types of pore structures in the process of hydrocarbon accumulation and development were simulated by combining the relative permeability experiment with the visual microscopic displacement model. It is shown that crotch-like viscous fingering occurs in the process of gas front advancing in reservoirs with different pore structures. The better the pore structure is, the lower the irreducible water saturation is; the higher the gas-phase relative permeability of irreducible water is, the more easily the gas reservoir can be developed. At the late stage of development, the residual gas is sealed in reservoirs in the forms of bypass, cutoff and dead end. In various reservoirs, the interference between gas and water is stronger, so gas and water tends to be produced simultaneously. The sealed gas may reduce the production rate of gas wells significantly, and the existence of water phase may reduce the gas permeability greatly; consequently, the water-bearing low-permeability tight sandstone gas reservoirs reveal serious water production, highly-difficult development and low-recovery percentage at the late stage, which have adverse impacts on the effective production and development of gas wells.

  6. Comparison of the diagenetic and reservoir quality evolution between the anticline crest and flank of an Upper Jurassic carbonate gas reservoir, Abu Dhabi, United Arab Emirates

    Science.gov (United States)

    Morad, Daniel; Nader, Fadi H.; Gasparrini, Marta; Morad, Sadoon; Rossi, Carlos; Marchionda, Elisabetta; Al Darmaki, Fatima; Martines, Marco; Hellevang, Helge

    2018-05-01

    This petrographic, stable isotopic and fluid inclusion microthermometric study of the Upper Jurassic limestones of an onshore field, Abu Dhabi, United Arab Emirates (UAE) compares diagenesis in flanks and crest of the anticline. The results revealed that the diagenetic and related reservoir quality evolution occurred during three phases, including: (i) eogenesis to mesogenesis 1, during which reservoir quality across the field was either deteriorated or preserved by calcite cementation presumably derived from marine or evolved marine pore waters. Improvement of reservoir quality was due to the formation of micropores by micritization of allochems and creation of moldic/intragranular pores by dissolution of peloids and skeletal fragments. (ii) Obduction of Oman ophiolites and formation of the anticline of the studied field was accompanied by cementation by saddle dolomite and blocky calcite. High homogenization temperatures (125-175 °C) and high salinity (19-26 wt% NaCl eq) of the fluid inclusions, negative δ18OVPDB values (-7.7 to -2.9‰), saddle shape of dolomite, and the presence of exotic cements (i.e. fluorite and sphalerite) suggest that these carbonates were formed by flux of hot basinal brines, probably related to this tectonic compression event. (iii) Mesogenesis 2 during subsidence subsequent to the obduction event, which resulted in extensive stylolitization and cementation by calcite. This calcite cement occluded most of the remaining moldic and inter-/intragranular pores of the flank limestones (water zone) whereas porosity was preserved in the crest. This study contributes to: (1) our understanding of differences in the impact of diagenesis on reservoir quality evolution in flanks and crests of anticlines, i.e. impact of hydrocarbon emplacement on diagenesis, and (2) relating various diagenetic processes to burial history and tectonic events of foreland basins in the Arabian Gulf area and elsewhere.

  7. Evidence for Sexual Dimorphism in the Plated Dinosaur Stegosaurus mjosi (Ornithischia, Stegosauria) from the Morrison Formation (Upper Jurassic) of Western USA.

    Science.gov (United States)

    Saitta, Evan Thomas

    2015-01-01

    Conclusive evidence for sexual dimorphism in non-avian dinosaurs has been elusive. Here it is shown that dimorphism in the shape of the dermal plates of Stegosaurus mjosi (Upper Jurassic, western USA) does not result from non-sex-related individual, interspecific, or ontogenetic variation and is most likely a sexually dimorphic feature. One morph possessed wide, oval plates 45% larger in surface area than the tall, narrow plates of the other morph. Intermediate morphologies are lacking as principal component analysis supports marked size- and shape-based dimorphism. In contrast, many non-sex-related individual variations are expected to show intermediate morphologies. Taphonomy of a new quarry in Montana (JRDI 5ES Quarry) shows that at least five individuals were buried in a single horizon and were not brought together by water or scavenger transportation. This new site demonstrates co-existence, and possibly suggests sociality, between two morphs that only show dimorphism in their plates. Without evidence for niche partitioning, it is unlikely that the two morphs represent different species. Histology of the new specimens in combination with studies on previous specimens indicates that both morphs occur in fully-grown individuals. Therefore, the dimorphism is not a result of ontogenetic change. Furthermore, the two morphs of plates do not simply come from different positions on the back of a single individual. Plates from all positions on the body can be classified as one of the two morphs, and previously discovered, isolated specimens possess only one morph of plates. Based on the seemingly display-oriented morphology of plates, female mate choice was likely the driving evolutionary mechanism rather than male-male competition. Dinosaur ornamentation possibly served similar functions to the ornamentation of modern species. Comparisons to ornamentation involved in sexual selection of extant species, such as the horns of bovids, may be appropriate in predicting the

  8. Main factors controlling the sedimentation of high-quality shale in the Wufeng–Longmaxi Fm, Upper Yangtze region

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    Yuman Wang

    2017-09-01

    Full Text Available In this paper, the shale of Upper Ordovician Wufeng Fm–Lower Silurian Longmaxi Fm was taken as an example to reveal the distribution patterns and the main sedimentation controlling factors of high-quality shale in the Upper Yangtze region. This study was made from the aspects of plate movement, fluctuation of sea level, palaeo-productivity, deposition rate and paleogeographic environment, based on the field outcrop sections and drilling data of the southern Sichuan Basin, together with geochemical element testing and biostratigraphical analysis results. The following findings were obtained. First, the collision and joint of Yangtze Plate and its periphery plates and the intra-plate deformation were gentle in the early stage, strong in the late stage, gentle in northwest and strong in southeast, so the sedimentation center in the Upper Yangtze region migrated to the northwest and the closure of sea area in the southern Sichuan Basin changed from weak in early stages to strong in late stages. Second, at the turning period from Ordovician to Silurian, sea levels presented the cycle change of deep–shallow–deep–shallow. Due to the combination of high sea levels and a stable ocean basin in early stages, an extensive anoxic tectonic sedimentary space favorable for organic matters preservation was formed in the sea floor. Third, due to the effect of tectonic movements and sea closure, palaeo-productivity of sea areas in the southern Sichuan Basin presented a trend of being high in the early stage and low in the late stage, and the deposition rate was also low in the early stage and high in the late stage. And fourth, extensive deposition and distribution of shale rich in organic matters and silica was mainly controlled by a stable sea basin with a low subsidence rate, a relatively high sea level, semi-closed waters and low deposition rates. To sum up, the high-quality shale in the Upper Yangtze region is characterized by multiphase

  9. Geothermal prospection in the Greater Geneva Basin (Switzerland and France). Impact of diagenesis on reservoir properties of the Upper Jurassic carbonate sediments

    Science.gov (United States)

    Makhloufi, Yasin; Rusillon, Elme; Brentini, Maud; Clerc, Nicolas; Meyer, Michel; Samankassou, Elias

    2017-04-01

    Diagenesis of carbonate rocks is known to affect the petrophysical properties (porosity, permeability) of the host rock. Assessing the diagenetic history of the rock is thus essential when evaluating any reservoir exploitation project. The Canton of Geneva (Switzerland) is currently exploring the opportunities for geothermal energy exploitation in the Great Geneva Basin (GGB) sub-surface. In this context, a structural analysis of the basin (Clerc et al., 2016) associated with reservoir appraisal (Brentini et al., 2017) and rock-typing of reservoir bodies of potential interest were conducted (Rusillon et al., 2017). Other geothermal exploitation projects elsewhere (e.g. Bavaria, south Germany, Paris Basin, France) showed that dolomitized carbonate rocks have good reservoir properties and are suitable for geothermal energy production. The objectives of this work are to (1) describe and characterize the dolomitized bodies in the GGB and especially their diagenetic history and (2) quantify the reservoir properties of those bodies (porosity, permeability). Currently, our study focuses on the Upper Jurassic sedimentary bodies of the GGB. Field and well data show that the dolomitization is not ubiquitous in the GGB. Results from the petrographical analyses of the Kimmeridgian cores (Humilly-2) and of field analogues (Jura, Saleve and Vuache mountains) display complex diagenetic histories, dependent of the study sites. The paragenesis exhibits several stages of interparticular calcite cementation as well as different stages of dolomitization and/or dedolomitization. Those processes seem to follow constrained path of fluid migrations through burial, faulting or exhumation during the basin's history. These complex diagenetic histories affected the petrophysical and microstructural properties via porogenesis (conservation of initial porosity, moldic porosity) and/or poronecrosis events. The best reservoir properties appear to be recorded in patch reef and peri

  10. Two look-alike dasycladalean algae: Clypeina isabellae masse, Bucur, Virgone & Delmasso, 1999 from the Berriasian of Sardinia (Italy and Clypeina loferensis sp. N. from the upper Jurassic of the Northern Calcareous Alps (Austria

    Directory of Open Access Journals (Sweden)

    Schlagintweit Felix

    2009-01-01

    Full Text Available New material from the Berriasian of eastern Sardinia, Italy, and from the NW of Sardinia published by PECORINI in 1972 as 'Clypeina sp. A', allows a better characterization and an emended diagnosis of Clypeina isabellae MASSE et al., 1999 from the Berriasian of SW France. Another morphologically somehow similar Clypeina species from the Upper Jurassic of the Northern Calcareous Alps of Austria is described as Clypeina loferensis n. sp. Remarks on the genera Clypeina MICHELIN and Hamulusella ELLIOTT, a Clypeina-type dasycladalean alga with proximal bulged laterals, and Clypeina jurassica-sulcata are also provided.

  11. Shale distillation

    Energy Technology Data Exchange (ETDEWEB)

    Blanding, F H

    1946-08-29

    A continuous method of distilling shale to produce valuable hydrocarbon oils is described which comprises providing a fluidized mass of the shale in a distillation zone, withdrawing hydrocarbon vapors from the zone, mixing fresh cold shale with the hydrocarbon vapors to quench the same, whereby the fresh shale is preheated, recovering hydrocarbon vapors and product vapors from the mixture and withdrawing preheated shale from the mixture and charging it to a shale distillation zone.

  12. U-Pb La-ICP-ms geochronology and regional correlation of middle Jurassic intrusive rocks from the Garzon Massif, Upper Magdalena Valley and central cordillera, southern Colombia

    International Nuclear Information System (INIS)

    Bustamante, Camilo; Cardona, Agustin; Bayona, German; Mora, Andres; Valencia, Victor; Gehrels, George; Vervoort, Jeff

    2010-01-01

    New U-Pb zircon geochronology from four granitic units sampled along a southeast-northwest transect between the Garzon massif and the Serrania de las Minas (central cordillera), records a middle Jurassic magmatic activity with two different spatio-temporal domains at ca. 189 ma and 180-173 ma. Reconnaissance data suggest that the four granitoids are characterized by mineralogical and geochemical characteristics akin to a continental magmatic arc setting. The new results suggest that the southern Colombian continental margin includes remnants of tectonomagmatic elements formed by the subduction of the Farallon plate under the South American continental margin. This middle Jurassic arc magmatism is part of the broader Andean scale arc province, and is significant for understanding the tectonic and paleogeographic scenario that characterized the Mesozoic tectonic evolution of the northern Andes.

  13. Origin, sequence stratigraphy and depositional environment of an Upper Ordovician (Hirnantian) deglacial black shale, Jordan-Discussion

    Czech Academy of Sciences Publication Activity Database

    Lüning, S.; Loydell, D. K.; Štorch, Petr; Shahin, Y.; Craig, J.

    2006-01-01

    Roč. 230, 3-4 (2006), s. 352-355 ISSN 0031-0182 Institutional research plan: CEZ:AV0Z30130516 Keywords : Silurian * black shale * sequence stratigraphy Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.822, year: 2006

  14. The Jurassic of Denmark and Greenland: Jurassic lithostratigraphy and stratigraphic development onshore and offshore Denmark

    Directory of Open Access Journals (Sweden)

    Michelsen, Olaf

    2003-10-01

    Full Text Available A complete updated and revised lithostratigraphic scheme for the Jurassic succession of the onshore and offshore Danish areas is presented together with an overview of the geological evolution. The lithostratigraphies of Bornholm, the Danish Basin and the Danish Central Graben are described in ascending order, and a number of new units are defined. On Bornholm, the Lower-Middle Jurassic coal-bearing clays and sands that overlie the Lower Pliensbachian Hasle Formation are referred to the new Sorthat Formation (Lower Jurassic and the revised Bagå Formation (Middle Jurassic. In the southern Danish Central Graben, the Middle Jurassic succession formerly referred to the Lower Graben Sand Formation is now included in the revised Bryne Formation. The Lulu Formation is erected to include the uppermost part of the Middle Jurassic succession, previously referred to the Bryne Formation in the northern Danish Central Graben. The Upper Jurassic Heno Formation is subdivided into two new members, the Gert Member (lower and the Ravn Member (upper. The organic-rich part of the upper Farsund Formation, the former informal `hot unit', is established formally as the Bo Member. Dominantly shallow marine and paralic deposition in the Late Triassic was succeeded by widespread deposition of offshore marine clays in the Early Jurassic. On Bornholm, coastal and paralic sedimentation prevailed. During maximum transgression in the Early Toarcian, sedimentation of organic-rich offshore clays took place in the Danish area. This depositional phase was terminated by a regional erosional event in early Middle Jurassic time, caused by uplift of the central North Sea area, including the Ringkøbing-Fyn High. In the Sorgenfrei-Tornquist Zone to the east, where slow subsidence continued, marine sandy sediments were deposited in response to the uplift. Uplift of the central North Sea area was followed by fault-controlled subsidence accompanied by fluvial and floodplain deposition

  15. Sedimentology, organic matter and diagenesis of fishscale shales in the molasse basin of upper Austria (Upper Eocene - Lower Oligocene); Sedimentologie, organisches Material und Diagenese des Fischschiefers im oberoesterreichischen Molasse-Becken (Obereozaen - Unteroligozaen)

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, H.M. [Inst. fuer Geologie und Palaeontologie der TU Clausthal, Clausthal-Zellerfeld (Germany); Sachsenhofer, R.F.; Bechtel, A. [Inst. fuer Geowiss. der Montanuniversitaet Leoben, Wien (Austria); Wagner, L.; Polesny, H.

    2002-07-01

    Fishscale shales (Schoeneck Formation) is an important parent rock of petroleum in prealpine molasse. Two different formation models are discussed, i.e. deposition and accumulation of organic matter (a) in a stagnating basin and (b) in a buoyancy zone. Both models were derived from samples, but they provide no information on the lithological and geochemical characteristics of complete fishscale shale sequences. This investigation focused on the vertical and lateral sedimentary development and the diagenetic changes of organic matter in the fishscale shales of upper Austria. Additionally, organic-geochemical data were used for validating the two deposition models. [German] Der Fischschiefer (Schoeneck Formation) stellt ein wichtiges Erdoelmuttergestein der alpinen Vorlandmolasse der. Waehrend seiner Ablagerung im Obereozaen(?)-Unteroligozaen wurde infolge der alpinen Orogenese die Paratethys von der Tethys abgetrennt und der Wasseraustausch zur Tethys eingeschraenkt. Gleichzeitig stroemten kalte Wassermassen ueber die polnische Senke in die Paratethys. Die Ablagerung der organisch-reichen Sedimente wird auf diese veraenderte palaeo-ozeanographische Situation zurueckgefuehrt. Zwei unterschiedliche Modelle werden fuer deren Bildung diskutiert: Ablagerung und Akkumulation von organischem Material in (a) einem stagnierenden Becken oder (b) in einer Auftriebszone. Die bislang diskutierten Modelle beruhen auf Ergebnissen vereinzelter Proben. Jedoch liegen keine Informationen hinsichtlich der lithologischen und geochemischen Charakteristika vollstaendiger Fischschiefer-Abfolgen vor. Es ist das Ziel dieses Beitrages, die vertikale und laterale sedimentaere Entwicklung, sowie die diagenetischen Veraenderungen des organischen Materials im Fischschiefer in Oberoesterreich vorzustellen. Zusaetzlich werden organisch-geochemische Daten eingesetzt, um die beiden vorgestellten Ablagerungsmodelle zu ueberpruefen. (orig.)

  16. Sedimentary evolution of the Mesozoic continental redbeds using geochemical and mineralogical tools: the case of Upper Triassic to Lowermost Jurassic Monte di Gioiosa mudrocks (Sicily, southern Italy)

    Science.gov (United States)

    Perri, Francesco; Critelli, Salvatore; Mongelli, Giovanni; Cullers, Robert L.

    2011-10-01

    The continental redbeds from the Internal Domains of the central-western Mediterranean Chains have an important role in the palaeogeographic and palaeotectonic reconstructions of the Alpine circum-Mediterranean orogen evolution since these redbeds mark the Triassic-Jurassic rift-valley stage of Tethyan rifting. The composition and the sedimentary evolution of the Middle Triassic to Lowermost Jurassic continental redbeds of the San Marco d'Alunzio Unit (Peloritani Mountains, Southern Italy), based on mineralogical and chemical analyses, suggests that the studied mudrock sediments share common features with continental redbeds that constitute the Internal Domains of the Alpine Mediterranean Chains. Phyllosilicates are the main components in the mudrocks. The 10 Å-minerals (illite and micas), the I-S mixed layers, and kaolinite are the most abundant phyllosilicates. The amount of illitic layers in I-S mixed layers coupled with the illite crystallinity values (IC) are typical of high degree of diagenesis, corresponding to a lithostatic/tectonic loading of about 4-5 km. The mineralogical assemblage coupled with the A-CN-K plot suggest post-depositional K-enrichments. Palaeoweathering proxies (PIA and CIW) record intense weathering at the source area. Further, the studied sediments are affected by reworking and recycling processes and, as consequence, it is likely these proxies monitor cumulative effect of weathering. The climate in the early Jurassic favoured recycling and weathering occurred under hot, episodically humid climate with a prolonged dry season. The source-area is the low-grade Paleozoic metasedimentary basement. Mafic supply is minor but not negligible as suggested by provenance proxies.

  17. A hyper-robust sauropodomorph dinosaur ilium from the Upper Triassic-Lower Jurassic Elliot Formation of South Africa: Implications for the functional diversity of basal Sauropodomorpha

    Science.gov (United States)

    McPhee, Blair W.; Choiniere, Jonah N.

    2016-11-01

    It has generally been held that the locomotory habits of sauropodomorph dinosaurs moved in a relatively linear evolutionary progression from bipedal through "semi-bipedal" to the fully quadrupedal gait of Sauropoda. However, there is now a growing appreciation of the range of locomotory strategies practiced amongst contemporaneous taxa of the latest Triassic and earliest Jurassic. Here we present on the anatomy of a hyper-robust basal sauropodomorph ilium from the Late Triassic-Early Jurassic Elliot Formation of South Africa. This element, in addition to highlighting the unexpected range of bauplan diversity throughout basal Sauropodomorpha, also has implications for our understanding of the relevance of "robusticity" to sauropodomorph evolution beyond generalized limb scaling relationships. Possibly representing a unique form of hindlimb stabilization during phases of bipedal locomotion, the autapomorphic morphology of this newly rediscovered ilium provides additional insight into the myriad ways in which basal Sauropodomorpha managed the inherited behavioural and biomechanical challenges of increasing body-size, hyper-herbivory, and a forelimb primarily adapted for use in a bipedal context.

  18. SICILIAN JURASSIC PHYSIOGRAPHY AND GEOLOGIC REALMS (ITALY

    Directory of Open Access Journals (Sweden)

    BENEDETTO ABATE

    2004-03-01

    Full Text Available Two tectono-sedimentary domains, which were deformed during the Neogene and evolved into two large structural sectors, characterize the Sicilian Jurassic: the Maghrebides and Peloritani. Africa margin sediments, passing downward to Triassic successions and perhaps originally to Paleozoic deposits, characterize the former. The latter belongs to the European "Calabrian Arc", where the Jurassic transgressively rests on a continental substrate (i.e. the crystalline Variscan basement. These domains are characterized by four sedimentary facies: shallow platform-derived limestones; condensed seamount-type red limestones; nodular limestones with ammonites; deep radiolarites and shales. These facies are illustrated in a dozen of stratigraphic logs. The drowning of most Triassic-Liassic carbonate platforms or ramps and the deepening of adjacent basins came with inferred Jurassic strike-slip tectonics, connected to the relative movement of Africa (Gondwanan part vs Europe (Laurasian part; the same strike-slip tectonics may have caused scattered intraplate volcanic seamounts found in Maghrebides. During the Jurassic the Maghrebide realm was characterized by the interfingering of basins and carbonate platforms. During the Early and Middle Liassic, carbonate platforms and ramps were dominant. Since Toarcian either radiolarites in some basins or Ammonite-bearing calcareous muds developed with intervening basaltic flows, and were accompanied by condensed pelagic carbonates on the ensialic seamount-type highs. The Peloritani realm displays similar characteristics, but with later transgression on the basement, several strike-slip basins and without any volcanoes.

  19. Shale distillation

    Energy Technology Data Exchange (ETDEWEB)

    Blanding, F H

    1948-08-03

    A continuous method of distilling shale to produce valuable hydrocarbon oils is described, which comprises providing a fluidized mass of the shale in a distillation zone, withdrawing hydrocarbon vapors containing shale fines from the zone, mixing sufficient fresh cold shale with the hydrocarbon vapors to quench the same and to cause condensation of the higher boiling constituents thereof, charging the mixture of vapors, condensate, and cold shale to a separation zone where the shale is maintained in a fluidized condition by the upward movement of the hydrocarbon vapors, withdrawing condensate from the separation zone and recycling a portion of the condensate to the top of the separation zone where it flows countercurrent to the vapors passing therethrough and causes shale fines to be removed from the vapors by the scrubbing action of the condensate, recovering hydrocarbon vapors and product vapors from the separation zone, withdrawing preheated shale from the separation zone and charging it to a shale distillation zone.

  20. Improved Oil Recovery from Upper Jurassic Smackover Carbonates through the Application of Advanced Technologies at Womack Hill Oil Field, Choctaw and Clarke Counties, Eastern Gulf Coastal Plain

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2003-12-31

    Pruet Production Co. and the Center for Sedimentary Basin Studies at the University of Alabama, in cooperation with Texas A&M University, Mississippi State University, University of Mississippi, and Wayne Stafford and Associates proposed a three-phase, focused, comprehensive, integrated and multidisciplinary study of Upper Jurassic Smackover carbonates (Class II Reservoir), involving reservoir characterization and 3-D modeling (Phase I) and a field demonstration project (Phases II and III) at Womack Hill Field Unit, Choctaw and Clarke Counties, Alabama, eastern Gulf Coastal Plain. Phase I of the project has been completed. The principal objectives of the project are: increasing the productivity and profitability of the Womack Hill Field Unit, thereby extending the economic life of this Class II Reservoir and transferring effectively and in a timely manner the knowledge gained and technology developed from this project to producers who are operating other domestic fields with Class II Reservoirs. The major tasks of the project included reservoir characterization, recovery technology analysis, recovery technology evaluation, and the decision to implement a demonstration project. Reservoir characterization consisted of geoscientific reservoir characterization, petrophysical and engineering property characterization, microbial characterization, and integration of the characterization data. Recovery technology analysis included 3-D geologic modeling, reservoir simulation, and microbial core experiments. Recovery technology evaluation consisted of acquiring and evaluating new high quality 2-D seismic data, evaluating the existing pressure maintenance project in the Womack Hill Field Unit, and evaluating the concept of an immobilized enzyme technology project for the Womack Hill Field Unit. The decision to implement a demonstration project essentially resulted in the decision on whether to conduct an infill drilling project in Womack Hill Field. Reservoir performance

  1. Improved Oil Recovery from Upper Jurassic Smackover Carbonates through the Application of Advanced Technologies at Womack Hill Oil Field, Choctaw and Clarke Counties, Eastern Gulf Costal Plain

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2006-05-31

    Pruet Production Co. and the Center for Sedimentary Basin Studies at the University of Alabama, in cooperation with Texas A&M University, Mississippi State University, University of Mississippi, and Wayne Stafford and Associates proposed a three-phase, focused, comprehensive, integrated and multidisciplinary study of Upper Jurassic Smackover carbonates (Class II Reservoir), involving reservoir characterization and 3-D modeling (Phase I) and a field demonstration project (Phases II and III) at Womack Hill Field Unit, Choctaw and Clarke Counties, Alabama, eastern Gulf Coastal Plain. Phase I of the project has been completed. The principal objectives of the project are: increasing the productivity and profitability of the Womack Hill Field Unit, thereby extending the economic life of this Class II Reservoir and transferring effectively and in a timely manner the knowledge gained and technology developed from this project to producers who are operating other domestic fields with Class II Reservoirs. The major tasks of the project included reservoir characterization, recovery technology analysis, recovery technology evaluation, and the decision to implement a demonstration project. Reservoir characterization consisted of geoscientific reservoir characterization, petrophysical and engineering property characterization, microbial characterization, and integration of the characterization data. Recovery technology analysis included 3-D geologic modeling, reservoir simulation, and microbial core experiments. Recovery technology evaluation consisted of acquiring and evaluating new high quality 2-D seismic data, evaluating the existing pressure maintenance project in the Womack Hill Field Unit, and evaluating the concept of an immobilized enzyme technology project for the Womack Hill Field Unit. The decision to implement a demonstration project essentially resulted in the decision on whether to conduct an infill drilling project in Womack Hill Field. Reservoir performance

  2. Parameters controlling fracturing distribution: example of an Upper Jurassic marly-calcareous formation (eastern Paris Basin); Parametres controlant la distribution de la fracturation: exemple dans une serie marno-calcaire du Jurassique superieur (Est du bassin de Paris)

    Energy Technology Data Exchange (ETDEWEB)

    Andre, G.; Rebours, H.; Wileveau, Y. [Agence Nationale pour la Gestion des Dechets Radioactifs (ANDRA), Laboratoire de recherche souterrain de Meuse/Haute-Marne, 55 - Bure (France); Proudhon, B. [GEO.TER, 34 - Clapiers (France)

    2006-10-15

    Study of fractures along a 490-m vertical section of marl/limestone alternations in the Upper Jurassic (Meuse/Haute-Marne underground research laboratory-eastern Paris Basin) reveals their organization and the different states of palaeo-stress. Type and extension of tectonic structures seem to be controlled principally by lithology and secondary by depth. Also, it appears deviations of Alpine palaeo-stresses between Kimmeridgian and Oxfordian formations. These deviations are related to the presence of marl/limestone contacts. The vertical evolution of current horizontal maximum stress shows a similar behaviour, with deviations at the walls of Callovo-Oxfordian argilites. These results allow us to point out and to discuss the impact of lithology, rheology and depth on fracturing occurrence and distribution. Furthermore, this study suggests the role of Callovo-Oxfordian as a barrier for fracture development between the limestones of Dogger and Oxfordian formations. (authors)

  3. Distilling shale

    Energy Technology Data Exchange (ETDEWEB)

    Armour, J; Armour, H

    1889-05-07

    The invention relates to retorts and accessory apparatus for distilling shale or other oil-yielding minerals. A series of long vertical retorts, composed of fire-brick or similar refractory material, are arranged in two rows in a bench, being divided into groups of four by transverse vertical partitions. The retorts are surmounted by metal casings or hoppers into which the fresh mineral is charged, and from which the distillate passes off through lateral pipes. Any uncondensed gases from the retorts may be passed into the flues surrounding them by the pipe and burned. The products of combustion from a furnace pass through a series of horizontal flues, being compelled to pass completely round each retort before entering the flue above. The products from two or more sets pass from the upper flues into flues running along the top of the bench, and return through a central flue to the chimney.

  4. Hydrocarbon potential of a new Jurassic play, central Tunisia

    International Nuclear Information System (INIS)

    Beall, A.O.; Law, C.W.

    1996-01-01

    A largely unrecognized Jurassic Sag Basin has been identified in central Tunisia, proximal to the Permo-Carboniferous flexure delineating the northern boundary of the Saharan platform of north Africa. The northwestern margin of the Sag is delineated by an extensive region of salt-cored anticlines and localized salt diapirs extending north and west. Due to lack of deep drilling, delineation of the Sag is largely based on regional gravity data. Subsidence of the Jurassic Sag Basin is characterized by rapid expansion of Jurassic sediments from 400 m. of tidal flat and shelf carbonate at the western outcrop to over 2000 meters of tidal flat and basinal carbonate and shale within the basin center, a five-fold expansion. Rapid loading of the basin continued into Lower Cretaceous time, marked by lateral flowage of Triassic salt into pronounced structural trends. Published source rock data and interpreted subsurface well data provided the basis for GENEX 1-D hydrocarbon generation and expulsion modeling of the Sag. Middle Jurassic black source shales typically contain Type II and Type III kerogens with T.O.C.'s ranging up to 4 percent. Modeling results indicate that middle Jurassic shales are presently mature for liquid generation within portions of the Sag, with maximum generation taking place during the Tertiary. Potential hydrocarbon generation yields, based on 60 meters of mature source shale, are 20,000 BOE/acre for gas and 75,000 BOE/acre for liquids. Prospects within the region could contain an estimated potential reserve of several T.C.F. or over 1 billion barrels of oil

  5. Jurassic Paleolatitudes, Paleogeography, and Climate Transitions In the Mexican Subcontinen

    Science.gov (United States)

    Molina-Garza, R. S.; Geissman, J. W.; Lawton, T. F.

    2014-12-01

    Jurassic northward migration of Mexico, trailing the North America plate, resulted in temporal evolution of climate-sensitive depositional environments. Lower-Middle Jurassic rocks in central Mexico contain a record of warm-humid conditions, which are indicated by coal and compositionally mature sandstone deposited in continental environments. Preliminary paleomagnetic data indicate that these rocks were deposited at near-equatorial paleolatitudes. The Middle Jurassic (ca. 170 Ma) Diquiyú volcanic sequence in central Oaxaca give an overall mean of D=82.2º/ I= +4.1º (n=10; k=17.3, α95=12º). In the Late Jurassic, the Gulf of Mexico formed as a subsidiary basin of the Atlantic Ocean, when the supercontinent Pangaea ruptured. Upper Jurassic strata, including eolianite and widespread evaporite deposits, across Mexico indicate dry-arid conditions. Available paleomagnetic data (compaction-corrected) from eolianites in northeast Mexico indicate deposition at ~15-20ºN. As North America moved northward during Jurassic opening of the Atlantic, different latitudinal regions experienced coeval Late Jurassic climatic shifts. Climate transitions have been widely recognized in the Colorado plateau region. The plateau left the horse-latitudes in the late Middle Jurassic to reach temperate humid climates at ~40ºN in the latest Jurassic. In turn, the southern end of the North America plate (central Mexico) reached arid horse-latitudes in the Late Jurassic. At that time, epeiric platforms developed in the circum-Gulf region after a long period of margin extension. We suggest that Upper Jurassic hydrocarbon source rocks in the circum-Gulf region accumulated on these platforms as warm epeiric hypersaline seas and the Gulf of Mexico itself were fertilized by an influx of wind-blown silt from continental regions. Additional nutrients were brought to shallow zones of photosynthesis by ocean upwelling driven by changes in the continental landmass configuration.

  6. Leakage detection of Marcellus Shale natural gas at an Upper Devonian gas monitoring well: a 3-d numerical modeling approach.

    Science.gov (United States)

    Zhang, Liwei; Anderson, Nicole; Dilmore, Robert; Soeder, Daniel J; Bromhal, Grant

    2014-09-16

    Potential natural gas leakage into shallow, overlying formations and aquifers from Marcellus Shale gas drilling operations is a public concern. However, before natural gas could reach underground sources of drinking water (USDW), it must pass through several geologic formations. Tracer and pressure monitoring in formations overlying the Marcellus could help detect natural gas leakage at hydraulic fracturing sites before it reaches USDW. In this study, a numerical simulation code (TOUGH 2) was used to investigate the potential for detecting leaking natural gas in such an overlying geologic formation. The modeled zone was based on a gas field in Greene County, Pennsylvania, undergoing production activities. The model assumed, hypothetically, that methane (CH4), the primary component of natural gas, with some tracer, was leaking around an existing well between the Marcellus Shale and the shallower and lower-pressure Bradford Formation. The leaky well was located 170 m away from a monitoring well, in the Bradford Formation. A simulation study was performed to determine how quickly the tracer monitoring could detect a leak of a known size. Using some typical parameters for the Bradford Formation, model results showed that a detectable tracer volume fraction of 2.0 × 10(-15) would be noted at the monitoring well in 9.8 years. The most rapid detection of tracer for the leak rates simulated was 81 days, but this scenario required that the leakage release point was at the same depth as the perforation zone of the monitoring well and the zones above and below the perforation zone had low permeability, which created a preferred tracer migration pathway along the perforation zone. Sensitivity analysis indicated that the time needed to detect CH4 leakage at the monitoring well was very sensitive to changes in the thickness of the high-permeability zone, CH4 leaking rate, and production rate of the monitoring well.

  7. Sequence stratigraphy, sedimentary systems and petroleum plays in a low-accommodation basin: Middle to upper members of the Lower Jurassic Sangonghe Formation, Central Junggar Basin, Northwestern China

    Science.gov (United States)

    Feng, Youliang; Jiang, Shu; Wang, Chunfang

    2015-06-01

    The Lower Jurassic Junggar Basin is a low-accommodation basin in northwestern China. Because of low subsidence rates and a warm, wet climate, deposits of the Central subbasin of the Junggar Basin formed from fluvial, deltaic, shallow lake facies. Sequence stratigraphy and sedimentary systems of the Lower Jurassic members of the Sangonghe Formation (J1s) were evaluated by observing cores, interpreting wireline logs and examining seismic profiles. Two third-order sequences were recognized in the strata. The distribution of the sedimentary systems in the systems tracts shows that tectonic movement, paleorelief, paleoclimate and changes in lake level controlled the architecture of individual sequences. During the development of the lowstand systems tract (LST), the intense structural movement of the basin resulted in a significant fall in the water level in the lake, accompanied by rapid accommodation decrease. Braided rivers and their deltaic systems were also developed in the Central Junggar Basin. Sediments carried by braided rivers were deposited on upward slopes of the paleorelief, and braid-delta fronts were deposited on downward slopes. During the transgressive systems tract (TST), the tectonic movement of the basin was quiescent and the climate was warm and humid. Lake levels rose and accommodation increased quickly, shoal lines moved landward, and shore- to shallow-lake deposits, sublacustrine fans and deep-lake facies were deposited in shallow- to deep-lake environments. During the highstand systems tract (HST), the accommodation no longer increased but sediment supply continued, far exceeding accommodation. HST deposits slowly formed in shallow-lake to meandering river delta-front environments. Relatively low rates of structural subsidence and low accommodation resulted in coarse-grained successions that were fining upward. Deposits were controlled by structural movement and paleorelief within the LST to TST deposits in the Central subbasin. Fine- to medium

  8. Traces in the dark: sedimentary processes and facies gradients in the upper shale member of the Upper Devonian-Lower Mississippian Bakken Formation, Williston Basin, North Dakota, U.S.A.

    Science.gov (United States)

    Egenhoff, Sven O.; Fishman, Neil S.

    2013-01-01

    Black, organic-rich rocks of the upper shale member of the Upper Devonian–Lower Mississippian Bakken Formation, a world-class petroleum source rock in the Williston Basin of the United States and Canada, contain a diverse suite of mudstone lithofacies that were deposited in distinct facies belts. The succession consists of three discrete facies associations (FAs). These comprise: 1) siliceous mudstones; 2) quartz- and carbonate-bearing, laminated mudstones; and 3) macrofossil-debris-bearing massive mudstones. These FAs were deposited in three facies belts that reflect proximal to distal relationships in this mudstone system. The macrofossil-debris-bearing massive mudstones (FA 3) occur in the proximal facies belt and contain erosion surfaces, some with overlying conodont and phosphate–lithoclast lag deposits, mudstones with abundant millimeter-scale siltstone laminae showing irregular lateral thickness changes, and shell debris. In the medial facies belt, quartz- and carbonate-bearing, laminated mudstones dominate, exhibiting sub-millimeter-thick siltstone layers with variable lateral thicknesses and localized mudstone ripples. In the distal siliceous mudstone facies belt, radiolarites, radiolarian-bearing mudstones, and quartz- and carbonate-bearing, laminated mudstones dominate. Overall, total organic carbon (TOC) contents range between about 3 and 10 wt %, with a general proximal to distal decrease in TOC content. Abundant evidence of bioturbation exists in all FAs, and the lithological and TOC variations are paralleled by changes in burrowing style and trace-fossil abundance. While two horizontal traces and two types of fecal strings are recognized in the proximal facies belt, only a single horizontal trace fossil and one type of fecal string characterize mudstones in the distal facies belt. Radiolarites intercalated into the most distal mudstones are devoid of traces and fecal strings. Bedload transport processes, likely caused by storm-induced turbidity

  9. Depositional environments and oil potential of Jurassic/Cretaceous source rocks within the Seychelles microcontinent

    Energy Technology Data Exchange (ETDEWEB)

    Plummer, P.S.; Joseph, P.R.; Samson, P.J. [Seychelles National Oil Co., Mahe (Seychelles)

    1998-12-31

    The Seychelles microcontinent became isolated between the Somali, Mascarene and Arabian basins of the Indian Ocean as a result of the Mesozoic fragmentation of Gondwana. Major rifting events occurred during the Triassic-Middle Jurassic and Late Cretaceous (Cenomanian-Santonian and Maastrichtian) during which shaly source rock facies accumulated in principally marginal marine/deltaic environments. Between these times, post-rift passive margin deposition within restricted to open marine environments produced shaly source rocks during late Middle Jurasic-Early Cretaceous, Campanian-Maastrichtian and Paleocene times. Recent geochemical analysis of cuttings from the Seagull Shoals-1 well has identified an oil-prone liptinitic (Type II) coaly shale within early Middle Jurassic abandoned deltaic deposits. This coaly source rock is regionally developed, having also been identified in the Majunja and Morondava basins of Madagascar. Oil-prone Type II organic matter has also been identified in the Owen Bank A-1 well within restricted marine shales of late Middle Jurassic age. These shales are part of a thick post-rift source rock sequence that extends into the Early Cretaceous and is in part correlative with the proven Late Jurassic Uarandab Shale of Somalia. Analysis of Campanian marine shales from Reith Bank-1 well identified significant dilution of total organic carbon content in composite, compared to picked, well cuttings samples. This finding supports a published inference that these post-rift shales have source rock potential. (author)

  10. Paleomagnetic tests for tectonic reconstructions of the Late Jurassic-Early Cretaceous Woyla Group, Sumatra

    Science.gov (United States)

    Advokaat, Eldert; Bongers, Mayke; van Hinsbergen, Douwe; Rudyawan, Alfend; Marshal, Edo

    2017-04-01

    SE Asia consists of multiple continental blocks, volcanic arcs and suture zones representing remnants of closing ocean basins. The core of this mainland is called Sundaland, and was formed by accretion of continental and arc fragments during the Paleozoic and Mesozoic. The former positions of these blocks are still uncertain but reconstructions based on tectonostratigraphic, palaeobiogeographic, geological and palaeomagnetic studies indicate the continental terranes separated from the eastern margin of Gondwana. During the mid-Cretaceous, more continental and arc fragments accreted to Sundaland, including the intra-oceanic Woyla Arc now exposed on Sumatra. These continental fragments were derived from Australia, but the former position of the Woyla Arc is unconstrained. Interpretations on the former position of the Woyla Arc fall in two end-member groups. The first group interprets the Woyla Arc to be separated from West Sumatra by a small back-arc basin. This back arc basin opened in the Late Jurassic, and closed mid-Cretaceous, when the Woyla Arc collided with West Sumatra. The other group interprets the Woyla Arc to be derived from Gondwana, at a position close to the northern margin of Greater India in the Late Jurassic. Subsequently the Woyla Arc moved northwards and collided with West Sumatra in the mid-Cretaceous. Since these scenarios predict very different plate kinematic evolutions for the Neotethyan realm, we here aim to place paleomagnetic constraints on paleolatitudinal evolution of the Woyla Arc. The Woyla Arc consists mainly of basaltic to andesitic volcanics and dykes, and volcaniclastic shales and sandstones. Associated limestones with volcanic debris are interpreted as fringing reefs. This assemblage is interpreted as remnants of an Early Cretaceous intra-oceanic arc. West Sumatra exposes granites, surrounded by quartz sandstones, shales and volcanic tuffs. These sediments are in part metamorphosed. This assemblage is interpreted as a Jurassic

  11. Gas storage in the Upper Devonian-Lower Mississippian Woodford Shale, Arbuckle Mountains, Oklahoma: how much of a role do the cherts play?

    Science.gov (United States)

    Fishman, Neil S.; Ellis, Geoffrey S.; Paxton, Stanley T.; Abbott, Marvin M.; Boehlke, Adam

    2010-01-01

    How gas is stored in shale-gas systems is a critical element in characterizing these potentially prolific, low-porosity/permeability reservoirs. An integrated mineralogic, geochemical, and porosity/permeability study is of the Upper Devonian-Lower Mississippian Woodford Shale, Arbuckle Mountains, southern Oklahoma, at locations previously described through detailed stratigraphic and spectral gamma surveys, was undertaken to provide insights into possible mechanisms by which natural gas might be stored in Woodford reservoirs in the adjacent Anadarko Basin. The outcrops in the Arbuckle Mountains are an ideal location to study the Woodford because here the formation is immature or marginally mature for oil generation (Comer and Hinch, 1987; Lewan, 1987), so deep burial and thermal maturation are much less pronounced than is the case for the Woodford in the basin, and as such the samples we studied are not overprinted by possible alterations resulting from deep burial and heating. Rock types studied in the Woodford Shale are broadly divided into chert (n = 8) and mudstone (n = 10) lithologies that display different characteristics from the outcrop to thin section scales. Woodford cherts, based on quantitative X-ray diffraction (XRD), contain >85 weight (wt) % quartz, green algae). Quartz in mudstones is both detrital and authigenic, with unequivocal authigenic quartz occurring as monocrystalline “grains” that can partly or even completely infill Tasmanites; as in the case of the cherts, authigenic quartz in mudstones must have precipitated soon after deposition before significant burial and collapse of the soft, delicate Tasmanites cysts. MICP analyses (at 50% Hg saturation) reveal that, with one exception, mudstones have (1) porosities ranging from 1.97-6.31%, (2) low calculated permeabilities (0.011-0.089 D), and (3) small mean pore apertures (6.2-17.8 nm). Porosity in the mudstones occurs as (1) “slots” between clay mineral grains or plates, (2) micropores

  12. Assessment of Appalachian basin oil and gas resources: Devonian gas shales of the Devonian Shale-Middle and Upper Paleozoic Total Petroleum System: Chapter G.9 in Coal and petroleum resources in the Appalachian basin: distribution, geologic framework, and geochemical character

    Science.gov (United States)

    Milici, Robert C.; Swezey, Christopher S.; Ruppert, Leslie F.; Ryder, Robert T.

    2014-01-01

    This report presents the results of a U.S. Geological Survey (USGS) assessment of the technically recoverable undiscovered natural gas resources in Devonian shale in the Appalachian Basin Petroleum Province of the eastern United States. These results are part of the USGS assessment in 2002 of the technically recoverable undiscovered oil and gas resources of the province. This report does not use the results of a 2011 USGS assessment of the Devonian Marcellus Shale because the area considered in the 2011 assessment is much greater than the area of the Marcellus Shale described in this report. The USGS assessment in 2002 was based on the identification of six total petroleum systems, which include strata that range in age from Cambrian to Pennsylvanian. The Devonian gas shales described in this report are within the Devonian Shale-Middle and Upper Paleozoic Total Petroleum System, which extends generally from New York to Tennessee. This total petroleum system is divided into ten assessment units (plays), four of which are classified as conventional and six as continuous. The Devonian shales described in this report make up four of these continuous assessment units. The assessment results are reported as fully risked fractiles (F95, F50, F5, and the mean); the fractiles indicate the probability of recovery of the assessment amount. The products reported are oil, gas, and natural gas liquids. The mean estimates for technically recoverable undiscovered hydrocarbons in the four gas shale assessment units are 12,195.53 billion cubic feet (12.20 trillion cubic feet) of gas and 158.91 million barrels of natural gas liquids

  13. Rock mechanics related to Jurassic underburden at Valdemar oil field

    DEFF Research Database (Denmark)

    Foged, Niels

    1999-01-01

    .It has been initiated as a feasibility study of the North Jens-1 core 12 taken in the top Jurassic clay shale as a test specimens for integrated petrological, mineralogical and rock mechanical studies. Following topics are studied:(1) Pore pressure generation due to conversion of organic matter...... and deformation properties of the clay shale using the actual core material or outcrop equivalents.(3) Flushing mechanisms for oil and gas from source rocks due to possibly very high pore water pressure creating unstable conditions in deeply burried sedimentsThere seems to be a need for integrating the knowledge...... in a number of geosciences to the benefit of common understanding of important reservoir mechanisms. Rock mechanics and geotechnical modelling might be key points for this understanding of reservoir geology and these may constitute a platform for future research in the maturing and migration from the Jurassic...

  14. Logging identification for the Lower Cambrian Niutitang shale reservoir in the Upper Yangtze region, China: A case study of the Cengong block, Guizhou Province

    Directory of Open Access Journals (Sweden)

    Ruyue Wang

    2016-06-01

    Full Text Available Currently, China has achieved a breakthrough in the Lower Silurian Longmaxi shale in Sichuan Basin and its surrounding areas. Compared to the Longmaxi shale, the Lower Cambrian Niutitang shale, which has a greater deposition thickness and wider distribution area, is another significant stratum for China's shale gas. Geophysical well logging is one of the most significant methods used for identification and evaluation of shale gas reservoirs throughout the process of shale gas exploration and development. In this paper, the logging response of the Niutitang shale is summarized to “four high and four low”, this was determined through a comparative analysis of three shale gas wells in the Cen'gong block. The Geochemical logging (GEM data shows that as the depth goes deeper the content of Si (quartz increases and the content of Al, Fe, K (Potassium, and Clay minerals decreases. In addition, the Niutitang shale mainly has the feature of a single peak or two continuous peaks in T2 spectrum on the nuclear magnetic resonance (NMR logging response. This has a longer T2 time and greater amplitude than normal shales. The logging response of various lithology and preservation is summarized by overlapping and a cross-plot analysis with the spectral gamma-ray, resistivity, density, acoustic, and compensated neutron logging data, which are sensitive to organic-rich shales. Moreover, the resistivity and acoustic logging data are sensitive to gas content, fluid properties, and preservation conditions, which can be used as indicators of shale gas content and preservation.

  15. Reworked Middle Jurassic sandstones as a marker for Upper Cretaceous basin inversion in Central Europe—a case study for the U-Pb detrital zircon record of the Upper Cretaceous Schmilka section and their implication for the sedimentary cover of the Lausitz Block (Saxony, Germany)

    Science.gov (United States)

    Hofmann, Mandy; Voigt, Thomas; Bittner, Lucas; Gärtner, Andreas; Zieger, Johannes; Linnemann, Ulf

    2018-04-01

    The Saxonian-Bohemian Cretaceous Basin (Elbsandsteingebirge, E Germany and Czech Republic, Elbtal Group) comprises Upper Cretaceous sedimentary rocks from Upper Cenomanian to Santonian age. These sandstones were deposited in a narrow strait of the sea linking the northern Boreal shelf to the southern Tethyan areas. They were situated between the West Sudetic Island in the north and the Mid-European Island in the south. As known by former studies (e.g. Tröger, Geologie 6/7:717-730, 1964; Tröger, Geologie von Sachsen, Schweizerbart, 311-358, 2008; Voigt and Tröger, Proceedings of the 4th International Cretaceous Symposium, 275-290, 1996; Voigt, Dissertation, TU Bergakademie Freiberg, 1-130, 1995; Voigt, Zeitschrift der geologischen Wissenschaften 37(1-2): 15-39, 2009; Wilmsen et al., Freiberger Forschungshefte C540: 27-45, 2011) the main sedimentary input came from the north (Lausitz Block, southern West-Sudetic Island). A section of Turonian to Coniacian sandstones was sampled in the Elbsandsteingebirge near Schmilka (Elbtal Group, Saxony, Germany). The samples were analysed for their U-Pb age record of detrital zircon using LA-ICP-MS techniques. The results show main age clusters typical for the Bohemian Massif (local material) and are interpreted to reflect the erosion of uniform quartz-dominated sediments and basement rocks. Surprisingly, these rocks lack an expected Upper Proterozoic to Lower Palaeozoic age peak, which would be typical for the basement of the adjacent Lausitz Block (c. 540-c. 560 Ma). Therefore, the Lausitz Block basement must have been covered by younger sediments that acted as source rocks during deposition of the Elbtal Group. The sandstones of the Elbe valley (Elbtal Group, Schmilka section) represent the re-deposited sedimentary cover of the Lausitz Block in inverse order. This cover comprised Permian, Triassic, Jurassic and Lower Cretaceous deposits, which are eroded already today and cannot be investigated. Within the samples of the

  16. Depositional environment and organic matter accumulation of Upper Ordovician–Lower Silurian marine shale in the Upper Yangtze Platform, South China

    Science.gov (United States)

    Li, Yangfang; Zhang, Tongwei; Ellis, Geoffrey S.; Shao, Deyong

    2017-01-01

    The main controlling factors of organic matter accumulation in the Upper Ordovician Wufeng–Lower Silurian Longmaxi Formations are complex and remain highly controversial. This study investigates the vertical variation of total organic carbon (TOC) content as well as major and trace element concentrations of four Ordovician–Silurian transition sections from the Upper Yangtze Platform of South China to reconstruct the paleoenvironment of these deposits and to improve our understanding of those factors that have influenced organic matter accumulation in these deposits.The residual TOC content of the Wufeng Formation averages 3.2% and ranges from 0.12 to 6.0%. The overlying lower Longmaxi Formation displays higher TOC content (avg. 4.4%), followed upsection by consistent and lower values that average 1.6% in the upper Longmaxi Formation. The concentration and covariation of redox-sensitive trace elements (Mo, U and V) suggest that organic-rich intervals of the Wufeng Formation accumulated under predominantly anoxic conditions. Organic-rich horizons of the lower Longmaxi Formation were deposited under strongly anoxic to euxinic conditions, whereas organic-poor intervals of the upper Longmaxi Formation accumulated under suboxic conditions. Positive correlations between redox proxies and TOC contents suggest that organic matter accumulation was predominantly controlled by preservation. Barium excess (Baxs) values indicate high paleoproductivity throughout the entire depositional sequence, with an increase in the lower Longmaxi Formation. Increased productivity may have been induced by enhanced P recycling, as evidenced by elevated Corg/Ptot ratios. Mo–U covariation and Mo/TOC values reveal that the Wufeng Formation was deposited under extremely restricted conditions, whereas the Longmaxi Formation accumulated under moderately restricted conditions. During the Late Ordovician, the extremely restricted nature of ocean circulation on the Upper Yangtze Platform in

  17. Lower-crustal xenoliths from Jurassic kimberlite diatremes, upper Michigan (USA): Evidence for Proterozoic orogenesis and plume magmatism in the lower crust of the southern Superior Province

    Science.gov (United States)

    Zartman, Robert E.; Kempton, Pamela D.; Paces, James B.; Downes, Hilary; Williams, Ian S.; Dobosi, Gábor; Futa, Kiyoto

    2013-01-01

    Jurassic kimberlites in the southern Superior Province in northern Michigan contain a variety of possible lower-crustal xenoliths, including mafic garnet granulites, rare garnet-free granulites, amphibolites and eclogites. Whole-rock major-element data for the granulites suggest affinities with tholeiitic basalts. P–T estimates for granulites indicate peak temperatures of 690–730°C and pressures of 9–12 kbar, consistent with seismic estimates of crustal thickness in the region. The granulites can be divided into two groups based on trace-element characteristics. Group 1 granulites have trace-element signatures similar to average Archean lower crust; they are light rare earth element (LREE)-enriched, with high La/Nb ratios and positive Pb anomalies. Most plot to the left of the geochron on a 206Pb/€204Pb vs 207Pb/€204Pb diagram, and there was probably widespread incorporation of Proterozoic to Archean components into the magmatic protoliths of these rocks. Although the age of the Group 1 granulites is not well constrained, their protoliths appear to be have been emplaced during the Mesoproterozoic and to be older than those for Group 2 granulites. Group 2 granulites are also LREE-enriched, but have strong positive Nb and Ta anomalies and low La/Nb ratios, suggesting intraplate magmatic affinities. They have trace-element characteristics similar to those of some Mid-Continent Rift (Keweenawan) basalts. They yield a Sm–Nd whole-rock errorchron age of 1046 ± 140 Ma, similar to that of Mid-Continent Rift plume magmatism. These granulites have unusually radiogenic Pb isotope compositions that plot above the 207Pb/€204Pb vs 206Pb/€204Pb growth curve and to the right of the 4·55 Ga geochron, and closely resemble the Pb isotope array defined by Mid-Continent Rift basalts. These Pb isotope data indicate that ancient continental lower crust is not uniformly depleted in U (and Th) relative to Pb. One granulite xenolith, S69-5, contains quartz, and has a

  18. Distilling shale

    Energy Technology Data Exchange (ETDEWEB)

    Heyl, G E

    1917-02-06

    The yield of oil obtained by distilling shale is increased by first soaking the shale with about 10 percent of its volume of a liquid hydrocarbon for a period of 24 hours or longer. Distillation is carried on up to a temperature of about 220/sup 0/C., and a further 10 percent of hydrocarbon is then added and the distillation continued up to a temperature of about 400/sup 0/C.

  19. Improvements in the distillation of shale, etc

    Energy Technology Data Exchange (ETDEWEB)

    Noad, J

    1912-09-20

    A process for treating shale and other bituminous substances containing sulfur and obtaining desulfurized products of distillation consisting in the consecutive steps of crushing the shale, mixing a suitable liquid with the shale granules, mixing slaked lime with the liquid coated shale granules, and gradually feeding the lime coated shale granules into a retort presenting a series of ledges or the like and working the shale granules down from ledge to ledge so that they are continuously agitated while being heated, the volatile constituents escaping through the lime coating and being conducted away from the upper part of the retort to suitable condensing apparatus, and the sulfur being arrested by the lime coating and together with the exhausted shale and other impurities being discharged from the lower part of the retort.

  20. On the origin of a phosphate enriched interval in the Chattanooga Shale (Upper Devonian) of Tennessee-A combined sedimentologic, petrographic, and geochemical study

    Science.gov (United States)

    Li, Yifan; Schieber, Juergen

    2015-11-01

    The Devonian Chattanooga Shale contains an uppermost black shale interval with dispersed phosphate nodules. This interval extends from Tennessee to correlative strata in Kentucky, Indiana, and Ohio and represents a significant period of marine phosphate fixation during the Late Devonian of North America. It overlies black shales that lack phosphate nodules but otherwise look very similar in outcrop. The purpose of this study is to examine what sets these two shales apart and what this difference tells us about the sedimentary history of the uppermost Chattanooga Shale. In thin section, the lower black shales (PBS) show pyrite enriched laminae and compositional banding. The overlying phosphatic black shales (PhBS) are characterized by phosbioclasts, have a general banded to homogenized texture with reworked layers, and show well defined horizons of phosphate nodules that are reworked and transported. In the PhBS, up to 8000 particles of P-debris per cm2 occur in reworked beds, whereas the background black shale shows between 37-88 particles per cm2. In the PBS, the shale matrix contains between 8-16 phosphatic particles per cm2. The shale matrix in the PhBS contains 5.6% inertinite, whereas just 1% inertinite occurs in the PBS. The shale matrix in both units is characterized by flat REE patterns (shale-normalized), whereas Phosbioclast-rich layers in the PhBS show high concentrations of REEs and enrichment of MREEs. Negative Ce-anomalies are common to all samples, but are best developed in association with Phosbioclasts. Redox-sensitive elements (Co, U, Mo) are more strongly enriched in the PBS when compared to the PhBS. Trace elements associated with organic matter (Cu, Zn, Cd, Ni) show an inverse trend of enrichment. Deposited atop a sequence boundary that separates the two shale units, the PhBS unit represents a transgressive systems tract and probably was deposited in shallower water than the underlying PBS interval. The higher phosphate content in the PhBS is

  1. Process for recovering oil from shale, etc

    Energy Technology Data Exchange (ETDEWEB)

    1920-08-20

    A process is described for recovering oil from oil-shale and the like, by the direct action of the hot gases obtained by burning the carbonized shale residue. It is immediately carried out in separate adjacent chambers, through which the feed goes from one to the other intermittently, from the upper to the lower.

  2. Distilling shale

    Energy Technology Data Exchange (ETDEWEB)

    Kern, L

    1922-07-21

    In the distillation of shale and similar materials the shale is ground and briquetted and the briquettes are placed in a retort so that air passages are left between them, after which they are uniformly and slowly heated to at least 700/sup 0/C, the air passages facilitating the escape of the oil vapors, and the slow heating preventing fusion of the flux forming constituents. After the bitumen has been driven off, air is passed into the retort and heating continued to about 1050/sup 0/C, the result being a porous product suitable for insulating purposes or as a substitute for kieselguhr. The ground shale may be mixed prior to distillation with peat, sawdust, or the like, and with substances which yield acids, such as chlorides, more particularly magnesium chloride, the acids acting on the bitumen.

  3. The Jurassic section along McElmo Canyon in southwestern Colorado

    Science.gov (United States)

    O'Sullivan, Robert B.

    1997-01-01

    In McElmo Canyon, Jurassic rocks are 1500-1600 ft thick. Lower Jurassic rocks of the Glen Canyon Group include (in ascending order) Wingate Sandstone, Kayenta Formation and Navajo Sandstone. Middle Jurassic rocks are represented by the San Rafael Group, which includes the Entrada Sandstone and overlying Wanakah Formation. Upper Jurassic rocks comprise the Junction Creek Sandstone overlain by the Morrison Formation. The Burro Canyon Formation, generally considered to be Lower Cretaceous, may be Late Jurassic in the McElmo Canyon area and is discussed with the Jurassic. The Upper Triassic Chinle Formation in the subsurface underlies, and the Upper Cretaceous Dakota Sandstone overlies, the Jurassic section. An unconformity is present at the base of the Glen Canyon Group (J-0), at the base of the San Rafael Group (J-2), and at the base of the Junction Creek Sandstone (J-5). Another unconformity of Cretaceous age is at the base of the Dakota Sandstone. Most of the Jurassic rocks consist of fluviatile, lacustrine and eolian deposits. The basal part of the Entrada Sandstone and the Wanakah Formation may be of marginal marine origin.

  4. Shale distillation

    Energy Technology Data Exchange (ETDEWEB)

    Jacomini, V V

    1938-06-07

    To produce valuable oils from shale by continuous distillation it is preheated by a heated fluid and introduced into a distilling retort from which the oil vapours and spent material are separately removed and the vapours condensed to recover the oil. The shale is preheated to 400 to 500/sup 0/F in the hopper by combustion gases from a flue and is fed in measured quantities to a surge drum, a loading chamber and surge drum, the latter two being connected to a steam pipe which equalises the pressure thereon. The material passes by two screw conveyors to a retort with deflector bars to scatter the material so that lean hot cycling gas flowing through a pipe is spread out as it makes its way upwardly through the shale and heats the oil so that it is driven off as vapour, collected in the lean gas and carried off through an outlet pipe. A measuring valve is provided at the bottom of a retort and cutter knives cut the spent shale and distribute cooling water thereto. The gases travel through heat exchangers and a condenser to an accumulator where the cycling gas is separated from the vapours, passed to compression, and preheated in a gas exchanger and spiral coils before it is returned to the retort. The oil passes to a storage tank by way of a unit tank in which oil vapours are recovered. Water is collected by a pipe in the tank bottom and returned by shaft to a retort.

  5. Shale processing

    Energy Technology Data Exchange (ETDEWEB)

    Hampton, W H

    1928-05-29

    The process of treating bituminiferous solid materials such as shale or the like to obtain valuable products therefrom, which comprises digesting a mixture of such material in comminuted condition with a suitable digestion liquid, such as an oil, recovering products vaporized in the digestion, and separating residual solid matter from the digestion liquid by centrifuging.

  6. JURASSIC PALEONTOLOGICAL HERITAGE OF MURCIA (BETIC CORDILLERA, SOUTH-EASTERN SPAIN

    Directory of Open Access Journals (Sweden)

    GREGORIO ROMERO

    2004-03-01

    Full Text Available Jurassic rocks of the External and Internal Zones of the Betic Cordillera are widespread in the province of Murcia. Four areas are considered of special interest for stratigraphical and paleontological analysis: a Sierra Quípar and b Sierras Lúgar-Corque (External Subbetic, c Sierra Ricote (Median Subbetic and d Sierra Espuña (Malaguide Complex. The first two contain Jurassic sections including Sinemurian-Tithonian deposits, and major stratigraphic discontinuities, containing significant cephalopod concentrations of taphonomic and taxonomic interest, occuring in the Lower-Upper Pliensbachian, Lower/Middle Jurassic and Middle/Upper Jurassic boundaries. These areas are also relevant for biostratigraphical analysis of the Middle-Upper Jurassic interval. In the Sierra de Ricote, the Mahoma section is of especial interest for the study of Lías/Dogger transition. Casa Chimeneas section constitutes the best Subbetic site for the analysis of the Lower/Upper Bajocian boundary. In the La Bermeja-Casas de Vite area, the Bajocian-Tithonian interval is well-represented, including a parastratotype of the Radiolarite Jarropa Formation. Finally, the Malvariche section in Sierra Espuña represents the best Jurassic succession of Internal Zones of the Betic Cordillera and could be considered as a reference section for this Betic Domain. In this paper a heritage evaluation has been carried out for these classical jurassic sections with the object of protecting these sites according to the legal framework prevailing in the province of Murcia.

  7. The influence of global sea level changes on European shale distribution and gas exploration

    Energy Technology Data Exchange (ETDEWEB)

    Turner, P.; Cornelius, C.T.; Clarke, H. [Cuadrilla Resources Ltd., Staffordshire (United Kingdom)

    2010-07-01

    Technological advances in directional drilling and hydraulic fracturing technology have unlocked new supplies of shale gas from reservoirs that were previously considered to be uneconomic. Several companies, both experienced majors and small independents, are currently evaluating the unconventional resource potential of mainland Europe. This paper demonstrated that global sea level changes govern the distribution of marine black shales. The Hallam Curve was used in this study to identify periods of prospective gas shale deposition. In general, these correspond to post-glacial periods of relatively high sea level. Under-filled marginal sedimentary basins are key exploration targets. The geochemical and petrophysical characteristics of the shales deposited under these conditions are often comparable to North American shales, particularly the Barnett Shale which is currently in production. Many orogenic events influence European shales in terms of organic maturity, hydrocarbon generation and fracture generation. The main prospective horizons in ascending stratigraphic sequence are the Alum Shale, Llandovery Shale, Fammenian/Frasnian Shale, Serpukhovian Shale, Toarcian Shale, Kimmeridge Clay and the Tertiary Eocene and Oligocene shales common to central Europe. This paper presented the authors initial exploration strategy, with particular focus on the Lower Palaeozoic of central Europe, the Namurian of northwest England and the Jurassic Posidonia Formation of the Roer Valley Graben in Holland. The potential obstacles to unconventional exploration in Europe include restricted access to surface locations, high water usage, a lack of convenient pipeline infrastructure, strict environmental regulations, a high population density and lack of suitable drilling rigs and well completion equipment. 13 refs., 7 figs.

  8. Discussion on the exploration & development prospect of shale gas in the Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Dazhong Dong

    2015-01-01

    Full Text Available The Sichuan Basin, a hotspot and one of the most successful areas for shale gas exploration and development, can largely reflect and have a big say in the future prospect of shale gas in China. Through an overall review on the progress in shale gas exploration and development in the Sichuan Basin, we obtained the following findings: (1 the Sichuan Basin has experienced the marine and terrestrial depositional evolution, resulting in the deposition of three types of organic-matter-rich shales (i.e. marine, transitional, and terrestrial, and the occurrence of six sets of favorable shale gas enrichment strata (i.e. the Sinian Doushantuo Fm, the Cambrian Qiongzhusi Fm, the Ordovician Wufeng–Silurian Longmaxi Fm, the Permian Longtan Fm, the Triassic Xujiahe Fm, and the Jurassic Zhiliujing Fm; (2 the five key elements for shale gas accumulation in the Wufeng-Longmaxi Fm are deep-water shelf facies, greater thickness of organic-rich shales, moderate thermal evolution, abundant structural fractures, reservoir overpressure; and (3 the exploration and development of shale gas in this basin still confronts two major challenges, namely, uncertain sweet spots and potential prospect of shale gas, and the immature technologies in the development of shale gas resources at a depth of more than 3500 m. In conclusion, shale gas has been discovered in the Jurassic, Triassic and Cambrian, and preliminary industrial-scale gas has been produced in the Ordovician-Silurian Fm in the Sichuan Basin, indicating a promising prospect there; commercial shale gas can be produced there with an estimated annual gas output of 30–60 billion m3; and shale gas exploration and production experiences in this basin will provide valuable theoretical and technical support for commercial shale gas development in China.

  9. The shale gas potential of the Opalinus Clay and Posidonia Shale in Switzerland - A first assessment

    Energy Technology Data Exchange (ETDEWEB)

    Leu, W. [Geoform Ltd, Villeneuve (Switzerland); Gautschi, A. [NAGRA, Wettingen (Switzerland)

    2014-07-01

    There has been recent interest in the shale gas potential of the Opalinus Clay and Posidonia Shale (Middle and Lower Jurassic) below the Swiss Molasse Basin in the light of the future role of domestic gas production within the expected future energy shift of Switzerland and possible conflicts in underground use. The Opalinus Clay of northern Switzerland is a potential host rock for repositories of both high-level and low-to-intermediate level radioactive waste and the exploitation of shale gas resources within or below this formation would represent a serious conflict of use. Well data from northern Switzerland shows that these two formations are unsuitable for future shale gas recovery. They never reached the gas window during their burial history (maturity values are ≤ 0.6% R{sub o}) and as a consequence never generated significant quantities of thermogenic gas. Geochemical data further shows that the average TOC values are in the range of 0.7%, i.e. clearly below accepted values of more than 1.5% for prospective shales. A review of available exploration data for the Opalinus Clay and Posidonia Shale in the deeper and western part of the Swiss Molasse Basin indicate that their shale gas potential may be substantial. The gross Posidonia Shale thickness increases from central Switzerland from less than 10 m to over 100 m in the Yverdon-Geneva area and is characterised by numerous bituminous intervals. A simplified shale gas resource calculation results for a geologically likely scenario in a technically recoverable gas volume of ∼120 billions m{sup 3}. The current database for such estimates is small and as a consequence, the uncertainties are large. However, these first encouraging results support a more detailed exploration phase with specific geochemical and petrophysical analysis of existing rock and well log data. (authors)

  10. The shale gas potential of the Opalinus Clay and Posidonia Shale in Switzerland - A first assessment

    International Nuclear Information System (INIS)

    Leu, W.; Gautschi, A.

    2014-01-01

    There has been recent interest in the shale gas potential of the Opalinus Clay and Posidonia Shale (Middle and Lower Jurassic) below the Swiss Molasse Basin in the light of the future role of domestic gas production within the expected future energy shift of Switzerland and possible conflicts in underground use. The Opalinus Clay of northern Switzerland is a potential host rock for repositories of both high-level and low-to-intermediate level radioactive waste and the exploitation of shale gas resources within or below this formation would represent a serious conflict of use. Well data from northern Switzerland shows that these two formations are unsuitable for future shale gas recovery. They never reached the gas window during their burial history (maturity values are ≤ 0.6% R o ) and as a consequence never generated significant quantities of thermogenic gas. Geochemical data further shows that the average TOC values are in the range of 0.7%, i.e. clearly below accepted values of more than 1.5% for prospective shales. A review of available exploration data for the Opalinus Clay and Posidonia Shale in the deeper and western part of the Swiss Molasse Basin indicate that their shale gas potential may be substantial. The gross Posidonia Shale thickness increases from central Switzerland from less than 10 m to over 100 m in the Yverdon-Geneva area and is characterised by numerous bituminous intervals. A simplified shale gas resource calculation results for a geologically likely scenario in a technically recoverable gas volume of ∼120 billions m 3 . The current database for such estimates is small and as a consequence, the uncertainties are large. However, these first encouraging results support a more detailed exploration phase with specific geochemical and petrophysical analysis of existing rock and well log data. (authors)

  11. The first finding of reliable Jurassic radiolarians in the Crimea

    Science.gov (United States)

    Vishnevskaya, V. S.; Alekseev, A. S.; Zhegallo, E. A.

    2017-02-01

    Radiolarians of Leugeonidae Yang et Wang, 1990, which represent a morphologically distinctive group of spherical radiolarians of the Spumellaria order, were found for the first time in Crimea and reliably confirm the Jurassic age of the finding. The nodules, which host the Jurassic radiolarians, were collected by A.S. Alekseev in 1983 in the terrigenous sequence of the Lozovskaya tectonic zone. The radiolarian assemblage in the nodules includes Levileugeo ordinarius Yang et Wang, Triactoma jonesi Pessagno, Pseudocrucella aff. prava Blome, Paronella kotura Baumgartner, P. ex gr. mulleri Pessagno, and Praeconocaryomma sp. The Levileugeo genus is easily identified due to its unique hexagonal element, which is typical only of the Jurassic, in particular, Upper Bajocian-Lower Tithonian radiolarians.

  12. Low durophagous predation on Toarcian (Early Jurassic ammonoids in the northwestern Panthalassa shelf basin

    Directory of Open Access Journals (Sweden)

    Yusuke Takeda

    2015-12-01

    Full Text Available Predatory shell breakage is known to occur occasionally on the ventrolateral portion of the body chamber in Mesozoic ammonoids. Here we report, for the first time, quantitative data of shell breakage in large ammonoid samples that were recovered from the lower Toarcian (Lower Jurassic strata in the Toyora area, western Japan. The strata yielding the ammonoid samples consisted mostly of well-laminated, bituminous black shale that was deposited in an oxygen-depleted shelf basin of the northwestern Panthalassa, under the influence of the early Toarcian oceanic anoxic event. Among a total of 1305 specimens from 18 localities, apparent shell breakage was recognised in 35 specimens belonging to 7 genera, resulting in only a 2.7% frequency of occurrence relative to the total number of specimens. The breakage occurs mostly on the ventrolateral side of the body chamber with a complete shell aperture. This fact, as well as the low energy bottom condition suggested for the ammonoid-bearing shale, indicate that the shell breaks observed in the examined ammonoids were not produced by non-biological, post-mortem biostratinomical processes but were lethal injuries inflicted by nektonic predators such as reptiles, jawed fishes, coleoids, nautiloids, and carnivorous ammonoids with calcified rostral tips in their upper and lower jaws. Similar predatory shell breaks on the ventrolateral side of the body chamber have been found in contemporaneous ammonoid assemblages of the Tethys Realm, with a much higher frequency of occurrence than in the examined samples from the northwestern Panthalassa, suggesting a weaker durophagous predation pressure on ammonoids in the latter bioprovince.

  13. New insights on the maturity distribution and shale gas potential of the Lower Saxony Basin, NW-Germany

    Energy Technology Data Exchange (ETDEWEB)

    Bruns, B.; Littke, R. [RWTH Aachen Univ. (Germany). Energy and Mineral Resources Group (EMR); Di Primio, R. [Deutsches GeoForchungsZentrum (GFZ), Potsdam (Germany). Sektion 4.3 - Organische Geochemie; Berner, U. [Bundesanstalt fuer Geowissenschaften und Rohstoffe (BGR), Hannover (Germany)

    2013-08-01

    Due to its economic relevance the Lower Saxony Basin has been intensively investigated. Consequently it can be regarded as a well-known example of a sedimentary basin that experienced strong inversion. Oil and gas source rocks of economical importance comprise Upper Carboniferous coals as well as Jurassic (Toarcian/Posidonia Shale) and Cretaceous (Berriasian/Wealden) marls. Many basin modeling projects have addressed this area but until now the tectonic and maturation history as well as the petroleum system evolution has not been evaluated in a high-resolution 3D model. Therefore, a fully integrated 3D high-resolution numerical petroleum system model was developed incorporating the Lower Saxony Basin and major parts of the Pompeckj Block, and Muensterland Basin. The burial and maturation history has been reconstructed calibrated by large amounts of vitrinite reflectance and downhole temperature data enabling the output of erosion and maturity distribution maps of superior quality. (orig.)

  14. Shale treatment

    Energy Technology Data Exchange (ETDEWEB)

    1941-03-03

    The charge of shale, coal, or the like, is placed in a cartridge which is inserted in a metal cylinder gas and/or steam heated to a temperature of between 300 to 500/sup 0/C is admitted through pipe and passes through two perforations through the charge which is held at a pressure of about .1 to 2 pounds per square inch and an out pipe together with evolved gases and vapours. A lid is clamped in position over the cartridge by means of an eye bolt and a nut.

  15. Jurassic sedimentary evolution of southern Junggar Basin: Implication for palaeoclimate changes in northern Xinjiang Uygur Autonomous Region, China

    Directory of Open Access Journals (Sweden)

    Shun-Li Li

    2014-04-01

    Full Text Available Junggar Basin, located in northern Xinjiang, presents continuous and multikilometer-thick strata of the Jurassic deposits. The Jurassic was entirely terrestrial fluvial and lacustrine deltaic sedimentation. Eight outcrop sections across the Jurassic strata were measured at a resolution of meters in southern Junggar Basin. Controlling factors of sedimentary evolution and palaeoclimate changes in Junggar Basin during the Jurassic were discussed based on lithology, fossils and tectonic setting. In the Early to Middle Jurassic, the warm and wide Tethys Sea generated a strong monsoonal circulation over the central Asian continent, and provided adequate moisture for Junggar Basin. Coal-bearing strata of the Badaowan, Sangonghe, and Xishanyao Formations were developed under warm and humid palaeoclimate in Junggar Basin. In the late Middle Jurassic, Junggar Basin was in a semi-humid and semi-arid environment due to global warming event. Stratigraphy in the upper part of the Middle Jurassic with less plant fossils became multicolor or reddish from dark color sediments. During the Late Jurassic, collision of Lhasa and Qiangtang Block obstructed monsoon from the Tethys Sea. A major change in climate from semi-humid and semi-arid to arid conditions took place, and reddish strata of the Upper Jurassic were developed across Junggar Basin.

  16. Distilling shale

    Energy Technology Data Exchange (ETDEWEB)

    Justice, P M

    1917-09-19

    Light paraffin oils and other oils for motors are obtained from shale, and benzene, toluene, and solvent naphtha are obtained from coal by a process in which the coal or shale is preferably powered to pass through a mesh of 64 to the inch and is heated with a mixture of finely ground carbonate or the like which under the action of heat gives off carbonic acid, and with small iron scrap or its equivalent which is adapted to increase the volume of hydrocarbons evolved. The temperature of the retort is maintained between 175 and 800/sup 0/C., and after all the vapors are given off at the higher temperature a fine jet of water may be injected into the retort and the temperature increased. The produced oil is condensed and purified by fractional distillation, and the gas formed is stored after passing it through a tower packed with coke saturated with a non-volatile oil with recovery of an oil of light specific gravity which is condensed in the tower. The residuum from the still in which the produced oil is fractionated may be treated with carbonate and iron, as in the first stage of the process, and the distillate therefrom passed to a second retort containing manganese dioxide and iron scrap preferably in the proportion of one part or two. The mixture, e.g., one containing shale or oil with six to thirteen percent of oxygen, to which is added three to eight per cent of carbonate, and from one and a half to four per cent of scrap iron, is conveyed by belts and an overhead skip to a hopper of a retort in a furnace heated by burners supplied with producer gas. The retort is fitted with a detachable lid and the vapors formed are led by a pipe to a vertical water-cooled condenser with a drain-cock which leads the condensed oils to a tank, from which a pipe leads to a packed tower for removing light oils and from which the gas passes to a holder.

  17. Detailed facies analysis of the Upper Cretaceous Tununk Shale Member, Henry Mountains Region, Utah: Implications for mudstone depositional models in epicontinental seas

    Science.gov (United States)

    Li, Zhiyang; Schieber, Juergen

    2018-02-01

    Lower-Middle Turonian strata of the Tununk Shale Member of the greater Mancos Shale were deposited along the western margin of the Cretaceous Western Interior Seaway during the Greenhorn second-order sea level cycle. In order to examine depositional controls on facies development in this mudstone-rich succession, this study delineates temporal and spatial relationships in a process-sedimentologic-based approach. The 3-dimensional expression of mudstone facies associations and their stratal architecture is assessed through a fully integrative physical and biologic characterization as exposed in outcrops in south-central Utah. Sedimentologic characteristics from the millimeter- to kilometer-scale are documented in order to fully address the complex nature of sediment transport mechanisms observed in this shelf muddy environment. The resulting facies model developed from this characterization consists of a stack of four lithofacies packages including: 1) carbonate-bearing, silty and sandy mudstone (CSSM), 2) silt-bearing, calcareous mudstone (SCM), 3) carbonate-bearing, silty mudstone to muddy siltstone (CMS), and 4) non-calcareous, silty and sandy mudstone (SSM). Spatial and temporal variations in lithofacies type and sedimentary facies characteristics indicate that the depositional environments of the Tununk Shale shifted in response to the 2nd-order Greenhorn transgressive-regressive sea-level cycle. During this eustatic event, the Tununk shows a characteristic vertical shift from distal middle shelf to outer shelf (CSSM to SCM facies), then from outer shelf to inner shelf environment (SCM to CMS, and to SSM facies). Shifting depositional environments, as well as changes in dominant paleocurrent direction throughout this succession, indicate multiple source areas and transport mechanisms (i.e. longshore currents, offshore-directed underflows, storm reworking). This study provides a rare documentation of the Greenhorn cycle as exposed across the entire shelf setting

  18. Shale retort

    Energy Technology Data Exchange (ETDEWEB)

    Overton, P C

    1936-07-22

    A vertical distillation retort with an enclosed annular heating chamber has enclosed therein tiered compartments spaced apart by chambers into which burners deliver heating gases which pass via ports to the chamber and thence to the atmosphere. Shale is delivered by means of an air tight chute to the uppermost compartment and is spread therein and passed downwardly from compartment to compartment through ports, finally passing from the retort through an airtight chute, by means of scrapers rotatably mounted on a hollow shaft through which noncondensible gases are delivered to the distilling material via jets. The gaseous products of distillation are educted through ports and a manifold, which is also in communication with the head of the retort through the delivery pipe.

  19. Modeling the Middle Jurassic ocean circulation

    Directory of Open Access Journals (Sweden)

    Maura Brunetti

    2015-10-01

    Full Text Available We present coupled ocean–sea-ice simulations of the Middle Jurassic (∼165 Ma when Laurasia and Gondwana began drifting apart and gave rise to the formation of the Atlantic Ocean. Since the opening of the Proto-Caribbean is not well constrained by geological records, configurations with and without an open connection between the Proto-Caribbean and Panthalassa are examined. We use a sea-floor bathymetry obtained by a recently developed three-dimensional (3D elevation model which compiles geological, palaeogeographical and geophysical data. Our original approach consists in coupling this elevation model, which is based on detailed reconstructions of oceanic realms, with a dynamical ocean circulation model. We find that the Middle Jurassic bathymetry of the Central Atlantic and Proto-Caribbean seaway only allows for a weak current of the order of 2 Sv in the upper 1000 m even if the system is open to the west. The effect of closing the western boundary of the Proto-Caribbean is to increase the transport related to barotropic gyres in the southern hemisphere and to change water properties, such as salinity, in the Neo-Tethys. Weak upwelling rates are found in the nascent Atlantic Ocean in the presence of this superficial current and we discuss their compatibility with deep-sea sedimentological records in this region.

  20. Geochemical evidences for palaeoclimatic fluctuations at the Triassic-Jurassic boundary: southwestern margin of the Neotethys in the Salt Range, Pakistan

    Science.gov (United States)

    Iqbal, Shahid; Wagreich, Michael; Jan, Irfanullah; Kürschner, Wolfram Michael; Gier, Susanne

    2017-04-01

    The Triassic-Jurassic boundary interval reveals a change from warm-arid to a warm and humid climate in the Tethyan domain. Sea-level reconstruction records across the European basins during this interval reveal an end-Triassic global regression event and is linked to the Central Atlantic Magmatic Province (CAMP) activity and Pangaea breakup. In the Tethyan Salt Range of Pakistan a succession of Upper Triassic dolomites/green-black mudstones (Kingriali Formation), overlying quartzose sandstone, mudstones, laterites and Lower Jurassic conglomerates/pebbly sandstones (Datta Formation) provides information on the palaeoclimatic evolution of the area. Preliminary palynological results from the mudstones indicate a Rhaetian age for the Kingriali Formation and a Hettangian age for the Datta Formation. X-ray diffraction (XRD) analysis of the mudstones (upper part of the Kingriali Formation) indicates the presence of mainly illite while kaolinite is a minor component. The kaolinite content, a reflection of the advanced stage of chemical weathering and hence warm-humid conditions, increases up-section in the overlying sandstone-mudstone succession. The overlying laterite-bauxite horizons lack illite/smectite and are entirely composed of kaolinite, boehmite and haematite. At places these kaolinite rich horizons are mined in the area (Western Salt Range). The bulk rock geochemistry of the succession confirms a similar trend. The Chemical Index of Alteration (CIA) displays an increasing trend from the Upper Triassic shales (CIA 75-80) through the overlying sandstones/mudstones-laterites to the overlying quartz rich sandstones and mudstones (CIA 90-97). The overall results for the succession reveal an increasing chemical maturity trend (increase in the intensity of chemical weathering) from Rhaetian to Hettangian thereby supporting a change from warm-arid to a warm-humid palaeoclimate, probably extreme greenhouse conditions.

  1. Multiple sulfur-isotopic evidence for a shallowly stratified ocean following the Triassic-Jurassic boundary mass extinction

    Science.gov (United States)

    Luo, Genming; Richoz, Sylvain; van de Schootbrugge, Bas; Algeo, Thomas J.; Xie, Shucheng; Ono, Shuhei; Summons, Roger E.

    2018-06-01

    The cause of the Triassic-Jurassic (Tr-J) boundary biotic crisis, one of the 'Big Five' mass extinctions of the Phanerozoic, remains controversial. In this study, we analyzed multiple sulfur-isotope compositions (δ33S, δ34S and δ36S) of pyrite and Spy/TOC ratios in two Tr-J successions (Mariental, Mingolsheim) from the European Epicontinental Seaway (EES) in order to better document ocean-redox variations during the Tr-J transition. Our results show that upper Rhaetian strata are characterized by 34S-enriched pyrite, low Spy/TOC ratios, and values of Δ33Spy (i.e., the deviation from the mass-dependent array) lower than that estimated for contemporaneous seawater sulfate, suggesting an oxic-suboxic depositional environment punctuated by brief anoxic events. The overlying Hettangian strata exhibit relatively 34S-depleted pyrite, high Δ33Spy, and Spy/TOC values, and the presence of green sulfur bacterial biomarkers indicate a shift toward to euxinic conditions. The local development of intense marine anoxia thus postdated the Tr-J mass extinction, which does not provide support for the hypothesis that euxinia was the main killing agent at the Tr-J transition. Sulfur and organic carbon isotopic records that reveal a water-depth gradient (i.e., more 34S-, 13C-depleted with depth) in combination with Spy/TOC data suggest that the earliest Jurassic EES was strongly stratified, with a chemocline located at shallow depths just below storm wave base. Shallow oceanic stratification may have been a factor for widespread deposition of black shales, a large positive shift in carbonate δ13C values, and a delay in the recovery of marine ecosystems following the Tr-J boundary crisis.

  2. The Devonian Marcellus Shale and Millboro Shale

    Science.gov (United States)

    Soeder, Daniel J.; Enomoto, Catherine B.; Chermak, John A.

    2014-01-01

    The recent development of unconventional oil and natural gas resources in the United States builds upon many decades of research, which included resource assessment and the development of well completion and extraction technology. The Eastern Gas Shales Project, funded by the U.S. Department of Energy in the 1980s, investigated the gas potential of organic-rich, Devonian black shales in the Appalachian, Michigan, and Illinois basins. One of these eastern shales is the Middle Devonian Marcellus Shale, which has been extensively developed for natural gas and natural gas liquids since 2007. The Marcellus is one of the basal units in a thick Devonian shale sedimentary sequence in the Appalachian basin. The Marcellus rests on the Onondaga Limestone throughout most of the basin, or on the time-equivalent Needmore Shale in the southeastern parts of the basin. Another basal unit, the Huntersville Chert, underlies the Marcellus in the southern part of the basin. The Devonian section is compressed to the south, and the Marcellus Shale, along with several overlying units, grades into the age-equivalent Millboro Shale in Virginia. The Marcellus-Millboro interval is far from a uniform slab of black rock. This field trip will examine a number of natural and engineered exposures in the vicinity of the West Virginia–Virginia state line, where participants will have the opportunity to view a variety of sedimentary facies within the shale itself, sedimentary structures, tectonic structures, fossils, overlying and underlying formations, volcaniclastic ash beds, and to view a basaltic intrusion.

  3. Hydrogenation of shale

    Energy Technology Data Exchange (ETDEWEB)

    Bedwell, A J; Clark, E D; Miebach, F W

    1935-09-28

    A process for the distillation, cracking, and hydrogenation of shale or other carbonaceous material consists in first distilling the material to produce hydrocarbon oils. Steam is introduced and is passed downwardly with hydrocarbon vapors from the upper portion of the retort where the temperature is maintained between 400/sup 0/C and 450/sup 0/C over the spent carbonaceous materials. The material is drawn off at the bottom of the retort which is maintained at a temperature ranging from 600/sup 0/C to 800/sup 0/C whereby the hydrocarbon vapors are cracked in the pressure of nascent hydrogen obtained by the action of the introduced steam on the spent material. The cracked gases and undecomposed steam are passed through a catalyst tower containing iron-magnesium oxides resulting in the formation of light volatile oils.

  4. The Jurassic of Denmark and Greenland: Shallow marine syn-rift sedimentation: Middle Jurassic Pelion Formation, Jameson Land, East Greenland

    Directory of Open Access Journals (Sweden)

    Engkilde, Michael

    2003-10-01

    Full Text Available The Middle Jurassic Pelion Formation – Fossilbjerget Formation couplet of Jameson Land, East Greenland, is a well-exposed example of the Middle Jurassic inshore–offshore successions characteristicof the rifted seaways in the Northwest European – North Atlantic region. Early Jurassic deposition took place under relatively quiet tectonic conditions following Late Permian – earliest Triassic and Early Triassic rift phases and the Lower Jurassic stratal package shows an overall layer-cake geometry. A long-term extensional phase was initiated in Middle Jurassic (Late Bajocian time, culminated in the Late Jurassic (Kimmeridgian–Volgian, and petered out in the earliest Cretaceous (Valanginian. The Upper Bajocian – Middle Callovian early-rift succession comprises shallow marine sandstones of the Pelion Formation and correlative offshore siltstones of theFossilbjerget Formation. Deposition was initiated by southwards progradation of shallow marine sands of the Pelion Formation in the Late Bajocian followed by major backstepping in Bathonian–Callovian times and drowning of the sandy depositional system in the Middle–Late Callovian. Six facies associations are recognised in the Pelion–Fossilbjerget couplet, representing estuarine, shoreface, offshore transition zone and offshore environments. The north–southtrendingaxis of the Jameson Land Basin had a low inclination, and deposition was sensitive to even small changes in relative sea level which caused the shorelines to advance or retreat over tens to several hundreds of kilometres. Eight composite sequences, termed P1–P8, are recognised and are subdivided into a total of 28 depositional sequences. The duration of the two orders of sequences was about 1–2 Ma and 360,000 years, respectively. The Upper Bajocian P1–2 sequencesinclude the most basinally positioned shallow marine sandstones, deposited during major sealevel lowstands. The lowstands were terminated by significant marine

  5. Geology of Paleozoic Rocks in the Upper Colorado River Basin in Arizona, Colorado, New Mexico, Utah, and Wyoming, Excluding the San Juan Basin

    Science.gov (United States)

    Geldon, Arthur L.

    2003-01-01

    is 0-2,500 feet thick and is composed almost entirely of Upper Devonian to Upper Mississippian limestone, dolomite, and chert. The overlying (Darwin-Humbug) zone is 0-800 feet thick and consists of Upper Mississippian limestone, dolomite, sandstone, shale, gypsum, and solution breccia. The Madison aquifer is overlain conformably by Upper Mississippian and Pennsylvanian rocks. The Madison aquifer in most areas is overlain by Upper Mississippian to Middle Pennsylvanian rocks of the Four Comers confining unit. The lower part of this confining unit, the Belden-Molas subunit, consists of as much as 4,300 feet of shale with subordinate carbonate rocks, sandstone, and minor gypsum. The upper part of the confining unit, the Paradox-Eagle Valley subunit, in most places consists of as much as 9,700 feet of interbedded limestone, dolomite, shale, sandstone, gypsum, anhydrite, and halite. Locally, the evaporitic rocks are deformed into diapirs as much as 15,000 feet thick. The Four Corners confining unit is overlain gradationally to disconformably by Pennsylvanian rocks. The uppermost Paleozoic rocks comprise the Canyonlands aquifer, which is composed of three zones with distinctly different lithologies. The basal (Cutler-Maroon) zone consists of as much as 16,500 feet of Lower Pennsylvanian to Lower Permian sandstone, conglomerate, shale, limestone, dolomite, and gypsum. The middle (Weber-De Chelly) zone consists of as much as 4,000 feet of Middle Pennsylvanian to Lower Permian quartz sandstone with minor carbonate rocks and shale. The upper (Park City-State Bridge) zone consists of as much as 800 feet of Lower to Upper Permian limestone, dolomite, shale, sandstone, phosphorite, chert, and gypsum. The Canyonlands aquifer is overlain disconformably to unconformably by formations of Triassic and Jurassic age.

  6. Process for retorting shale

    Energy Technology Data Exchange (ETDEWEB)

    1952-03-19

    The method of retorting oil shale to recover valuable liquid and gaseous hydrocarbons consists of heating the oil shale in a retorting zone to a temperature sufficient to convert its kerogenic constituents to normally liquid and normally gaseous hydrocarbons by contact with hot gas previously recovered from shale, cooling the gases and vapors effluent from the retorting zone by direct countercurrent contact with fresh shale to condense the normally liquid constituents of the gases and vapors, separating the fixed gas from the liquid product, heating the fixed gas, and returning it to the retorting zone to contact further quantities of shale.

  7. Bald Mountain gold mining district, Nevada: A Jurassic reduced intrusion-related gold system

    Science.gov (United States)

    Nutt, C.J.; Hofstra, A.H.

    2007-01-01

    The Bald Mountain mining district has produced about 2 million ounces (Moz) of An. Geologic mapping, field relationships, geochemical data, petrographic observations, fluid inclusion characteristics, and Pb, S, O, and H isotope data indicate that An mineralization was associated with a reduced Jurassic intrusion. Gold deposits are localized within and surrounding a Jurassic (159 Ma) quartz monzonite porphyry pluton and dike complex that intrudes Cambrian to Mississippian carbonate and clastic rocks. The pluton, associated dikes, and An mineralization were controlled by a crustal-scale northwest-trending structure named the Bida trend. Gold deposits are localized by fracture networks in the pluton and the contact metamorphic aureole, dike margins, high-angle faults, and certain strata or shale-limestone contacts in sedimentary rocks. Gold mineralization was accompanied by silicification and phyllic alteration, ??argillic alteration at shallow levels. Although An is typically present throughout, the system exhibits a classic concentric geochemical zonation pattern with Mo, W, Bi, and Cu near the center, Ag, Pb, and Zn at intermediate distances, and As and Sb peripheral to the intrusion. Near the center of the system, micron-sized native An occurs with base metal sulfides and sulfosalts. In peripheral deposits and in later stages of mineralization, Au is typically submicron in size and resides in pyrite or arsenopyrite. Electron microprobe and laser ablation ICP-MS analyses show that arsenopyrite, pyrite, and Bi sulfide minerals contain 10s to 1,000s of ppm Au. Ore-forming fluids were aqueous and carbonic at deep levels and episodically hypersaline at shallow levels due to boiling. The isotopic compositions of H and O in quartz and sericite and S and Pb in sulfides are indicative of magmatic ore fluids with sedimentary sulfur. Together, the evidence suggests that Au was introduced by reduced S-bearing magmatic fluids derived from a reduced intrusion. The reduced

  8. Paleoenvironments of the Jurassic and Cretaceous Oceans: Selected Highlights

    Science.gov (United States)

    Ogg, J. G.

    2007-12-01

    There are many themes contributing to the sedimentation history of the Mesozoic oceans. This overview briefly examines the roles of the carbonate compensation depth (CCD) and the associated levels of atmospheric carbon dioxide, of the evolution of marine calcareous microplankton, of major transgressive and regressive trends, and of super-plume eruptions. Initiation of Atlantic seafloor spreading in the Middle Jurassic coincided with an elevated carbonate compensation depth (CCD) in the Pacific-Tethys mega-ocean. Organic-rich sediments that would become the oil wealth of regions from Saudi Arabia to the North Sea were deposited during a continued rise in CCD during the Oxfordian-early Kimmeridgian, which suggests a possible increase in carbon dioxide release by oceanic volcanic activity. Deep-sea deposits in near-equatorial settings are dominated by siliceous shales or cherts, which reflect the productivity of siliceous microfossils in the tropical surface waters. The end-Jurassic explosion in productivity by calcareous microplankton contributed to the lowering of the CCD and onset of the chalk ("creta") deposits that characterize the Tithonian and lower Cretaceous in all ocean basins. During the mid-Cretaceous, the eruption of enormous Pacific igneous provinces (Ontong Java Plateau and coeval edifices) increased carbon dioxide levels. The resulting rise in CCD terminated chalk deposition in the deep sea. The excess carbon was progressively removed in widespread black-shale deposits in the Atlantic basins and other regions - another major episode of oil source rock. A major long-term transgression during middle and late Cretaceous was accompanied by extensive chalk deposition on continental shelves and seaways while the oceanic CCD remained elevated. Pacific guyots document major oscillations (sequences) of global sea level superimposed on this broad highstand. The Cretaceous closed with a progressive sea-level regression and lowering of the CCD that again enabled

  9. Shale gas. Shale gas formation and extraction

    International Nuclear Information System (INIS)

    Renard, Francois; Artru, Philippe

    2015-10-01

    A first article recalls the origin of shale gases and technological breakthroughs which allowed their exploitation, describes the development of shale gas exploitation in the USA during the 2000's and the consequences for the gas and electricity markets, and discusses the various environmental impacts (risks of pollution of aquifers, risks of induced seismicity, use and processing of drilling and production waters). The second article describes the formation of shale gas: presence of organic matter in sediments, early evolution with the biogenic gas, burrowing, diagenesis and oil formation, thermal generation of gas (condensates and methane). The author indicates the location of gas within the rock, and the main sites of shale oils and shale gases in the World. In the next part, the author describes the various phases of shale gas extraction: exploration, oriented drillings, well preparation for hydraulic fracturing, fracturing, processing of fracturing fluids, flow-back, gas production and transport, aquifer protection. He finally gives a brief overview of technical evolution and of shale gas economy

  10. Shale engineering application: the MAL-145 project in West Virginia

    Energy Technology Data Exchange (ETDEWEB)

    Vassilellis, George D.; Li, Charles; Bust, Vivian K. [Gaffney, Cline and Associates (United States); Moos, Daniel; Cade, Randal [Baker Hughes Inc (United States)

    2011-07-01

    With the depletion of conventional fossil fuels and the rising energy demand, oil shale and shale gas are becoming an important component of the oil and gas markets in North America. The aim of this paper is to present a novel methodology for predicting production in shale and tight formations. This method, known as the shale engineering approach and modeling, provides reservoir simulations based on modeling the propagation of the simulated rock volume. This technique was applied to an Upper Devonian shale formation in West Virginia, United States, and was compared to available data such as production logs and downhole microseismic data. Results showed a good match between the shale engineering approach data and early well performance. This paper presented a new reservoir simulation methodology which is successful in forecasting production and which can also be used for field development design and optimization.

  11. Marine Jurassic lithostratigraphy of Thailand

    Science.gov (United States)

    Meesook, A.; Grant-Mackie, J. A.

    Marine Jurassic rocks of Thailand are well-exposed in the Mae Sot and Umphang areas and less extensively near Mae Hong Son, Kanchanaburi, Chumphon and Nakhon Si Thammarat, in the north, west, and south respectively. They are generally underlain unconformably by Triassic and overlain by Quaternary strata. Based mainly on five measured sections, fourteen new lithostratigraphic units are established: (in ascending order) Pa Lan, Mai Hung and Kong Mu Formations of the Huai Pong Group in the Mae Hong Son area; Khun Huai, Doi Yot and Pha De Formations of the Hua Fai Group in the Mae Sot area; Klo Tho, Ta Sue Kho, Pu Khloe Khi and Lu Kloc Tu Formations of the Umphang Group in the Umphang area; and the Khao Lak Formation in the Chumphon area. Mudstone, siltstone, sandstone, limestone and marl are the dominant lithologies. Mudstones, siltstones and sandstones are widespread; limestones are confined to the Mae Sot, Umphang, Kanchanaburi and Mae Hong Son areas; marls are found only in Mae Sot. The sequences are approximately 900 m thick in Mae Sot and 450 m thick in Umphang and are rather thinner in the other areas, particularly in the south. Based on ammonites, with additional data from bivalves and foraminifera, the marine Jurassic is largely Toarcian-Aalenian plus some Bajocian. Late Jurassic ages given previously for strata in the Mae Sot and Umphang areas have not been confirmed.

  12. Oil shale commercialization study

    Energy Technology Data Exchange (ETDEWEB)

    Warner, M.M.

    1981-09-01

    Ninety four possible oil shale sections in southern Idaho were located and chemically analyzed. Sixty-two of these shales show good promise of possible oil and probable gas potential. Sixty of the potential oil and gas shales represent the Succor Creek Formation of Miocene age in southwestern Idaho. Two of the shales represent Cretaceous formations in eastern Idaho, which should be further investigated to determine their realistic value and areal extent. Samples of the older Mesozonic and paleozoic sections show promise but have not been chemically analyzed and will need greater attention to determine their potential. Geothermal resources are of high potential in Idaho and are important to oil shale prospects. Geothermal conditions raise the geothermal gradient and act as maturing agents to oil shale. They also might be used in the retorting and refining processes. Oil shales at the surface, which appear to have good oil or gas potential should have much higher potential at depth where the geothermal gradient is high. Samples from deep petroleum exploration wells indicate that the succor Creek shales have undergone considerable maturation with depth of burial and should produce gas and possibly oil. Most of Idaho's shales that have been analyzed have a greater potential for gas than for oil but some oil potential is indicated. The Miocene shales of the Succor Creek Formation should be considered as gas and possibly oil source material for the future when technology has been perfectes. 11 refs.

  13. Seismic prediction of sweet spots in the Da'anzhai shale play, Yuanba area, the Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Peng Changzi

    2014-12-01

    Full Text Available Burial depth, thickness, total organic carbon (TOC content, brittleness and fracture development of shale reservoirs are the main geologic indexes in the evaluation of sweet spots in shale gas plays. Taking the 2nd interval of Da'anzhai shale of the Lower Jurassic as the study object, a set of techniques in seismic prediction of sweet spots were developed based on special processing of seismic data and comprehensive analysis of various data based on these geologic indexes. First, logging and seismic responses of high quality shales were found out through fine calibration of shale reservoir location with seismogram, which was combined with seismic facies analysis to define the macroscopic distribution of the shale. Then, seismic impedance inversion and GR inversion were used to identify shale from limestone and sandstone. Based on statistical analysis of sensitive parameters such as TOC, the uranium log inversion technique was used to quantitatively predict TOC of a shale reservoir and the thickness of a high quality shale reservoir. After that, fracture prediction technique was employed to predict play fairways. Finally, the pre-stack joint P-wave and S-wave impedance inversion technique was adopted to identify shales with high brittleness suitable for hydraulic fracturing. These seismic prediction techniques have been applied in sorting out sweet spots in the 2nd interval of the Da'anzhai shale play of the Yuanba area, and the results provided a sound basis for the optimization of horizontal well placement and hydraulic fracturing.

  14. Factors controlling the compositional variations among the marine and non-marine black shales from Egypt

    Energy Technology Data Exchange (ETDEWEB)

    Baioumy, Hassan M. [Central Metallurgical R and D Institute, PO Box 87 Helwan, Cairo (Egypt); Ismael, Ismael S. [Faculty of Science, Suez Canal University, Suez (Egypt)

    2010-07-01

    Non-marine (Jurassic) and marine (Cretaceous) black shales from Egypt were subjected to mineralogical and geochemical analyses to examine the controlling factors of their compositional variations. Non-marine black shales are composed of kaolinite and quartz with traces of gypsum, illite, calcite, feldspars, and dolomite, while marine black shales from the Red Sea area are composed of smectite, kaolinite, quartz, calcite, and dolomite with traces of feldspars. Abu Tartur marine black shales are composed of smectite and quartz with traces of feldspars and gypsum. Non-marine black shales show considerably higher Nb, Ta, Hf, and Zr contents and Th/Yb ratios compared to the marine black shales. On the other hand, marine black shales show considerably higher Cr, V, and Zn contents with positive correlations between these elements and organic carbon (C{sub org.}){sub .} Red Sea black shales have higher Ni/Co, V/Cr, and U/Al ratios. Chondrite normalized values of the medium and heavy rare earth elements (MREEs and HREEs, respectively) are higher in the non-marine black shales compared to the marine black shales. Pyrite from non-marine black shales is characterized by high positive {delta}{sup 34}S isotope values (average of + 9.3 permille). Pyrite from Red Sea black shales has low negative {delta}{sup 34}S values (average of -16.7 permille), pyrite from black shales of the lower member of the Duwi Formation has positive {delta}{sup 34}S values (average of 5.8 permille), while pyrite from marine black shales of the middle member has negative {delta}{sup 34}S values (average of -0.83 permille). Source area composition, weathering conditions, depositional environments, and type of organic matter are considered to be the probable controlling factors of these variations. The more felsic constituents in the source area of non-marine black shales is responsible for the relatively high Nb, Ta, Hf, and Zr contents and Th/Yb ratio. Relatively high kaolinite contents and Chemical

  15. Variations in petrophysical properties of shales along a stratigraphic section in the Whitby mudstone (UK)

    Science.gov (United States)

    Barnhoorn, Auke; Houben, Maartje; Lie-A-Fat, Joella; Ravestein, Thomas; Drury, Martyn

    2015-04-01

    In unconventional tough gas reservoirs (e.g. tight sandstones or shales) the presence of fractures, either naturally formed or hydraulically induced, is almost always a prerequisite for hydrocarbon productivity to be economically viable. One of the formations classified so far as a potential interesting formation for shale gas exploration in the Netherlands is the Lower Jurassic Posidonia Shale Formation (PSF). However data of the Posidonia Shale Formation is scarce so far and samples are hard to come by, especially on the variability and heterogeneity of the petrophysical parameters of this shale little is known. Therefore research and sample collection is conducted on a time and depositional analogue of the PSF: the Whitby Mudstone Formation (WMF) in the United Kingdom. A large number of samples along a ~7m stratigraphic section of the Whitby Mudstone Formation have been collected and analysed. Standard petrophysical properties such as porosity and matrix densities are quantified for a number of samples throughout the section, as well as mineral composition analysis based on XRD/XRF and SEM analyses. Seismic velocity measurements are also conducted at multiple heights in the section and in multiple directions to elaborate on anisotropy of the material. Attenuation anisotropy is incorporated as well as Thomsen's parameters combined with elastic parameters, e.g. Young's modulus and Poisson's ratio, to quantify the elastic anisotropy. Furthermore rock mechanical experiments are conducted to determine the elastic constants, rock strength, fracture characteristics, brittleness index, fraccability and rock mechanical anisotropy across the stratigraphic section of the Whitby mudstone formation. Results show that the WMF is highly anisotropic and it exhibits an anisotropy on the large limit of anisotropy reported for US gas shales. The high anisotropy of the Whitby shales has an even larger control on the formation of the fracture network. Furthermore, most petrophysical

  16. The occurrence of a shallow-water Ammobaculoides assemblage in the Middle Jurassic (Bajocian) Dhruma Formation of Central Saudi Arabia

    Science.gov (United States)

    Kaminski, Michael A.; Hammad Malik, Muhammad; Setoyama, Eiichi

    2018-01-01

    We report the occurrence of an Ammobaculoides-dominated assemblage in the lowermost member of the Middle Jurassic Dhruma Formation exposed west of Riyadh, Saudi Arabia. The new species Ammobaculoides dhrumaensis n.sp. is described from the green shale of the D1 unit (also known as the Balum Member) of the Dhruma Formation, which has been assigned an early Bajocian age based on ammonites. Our new finding constitutes the oldest reported worldwide occurrence of the agglutinated foraminiferal genus Ammobaculoides Plummer, 1932.

  17. Shale Gas and Oil in Germany - Resources and Environmental Impacts

    Science.gov (United States)

    Ladage, Stefan; Blumenberg, Martin; Houben, Georg; Pfunt, Helena; Gestermann, Nicolai; Franke, Dieter; Erbacher, Jochen

    2017-04-01

    In light of the controversial debate on "unconventional" oil and gas resources and the environmental impacts of "fracking", the Federal Institute for Geosciences and Natural Resources (BGR) conducted a comprehensive resource assessment of shale gas and light tight oil in Germany and studied the potential environmental impacts of shale gas development and hydraulic fracturing from a geoscientific perspective. Here, we present our final results (BGR 2016), incorporating the majority of potential shale source rock formations in Germany. Besides shale gas, light tight oil has been assessed. According to our set of criteria - i.e. thermal maturity 0.6-1.2 %vitrinite reflectance (VR; oil) and >1.2 % VR (gas) respectively, organic carbon content > 2%, depth between 500/1000 m and 5000 m as well as a net thickness >20 m - seven potentially generative shale formations were indentified, the most important of them being the Lower Jurassic (Toarcian) Posidonia shale with both shale gas and tight oil potential. The North German basin is by far the most prolific basin. The resource assessment was carried out using a volumetric in-place approach. Variability inherent in the input parameters was accounted for using Monte-Carlo simulations. Technically recoverable resources (TRR) were estimated using recent, production-based recovery factors of North American shale plays and also employing Monte-Carlo simulations. In total, shale gas TRR range between 320 and 2030 bcm and tight oil TRR between 13 and 164 Mio. t in Germany. Tight oil potential is therefore considered minor, whereas the shale gas potential exceeds that of conventional resources by far. Furthermore an overview of numerical transport modelling approaches concerning environmental impacts of the hydraulic fracturing is given. These simulations are based on a representative lithostratigraphy model of the North-German basin, where major shale plays can be expected. Numerical hydrogeological modelling of frac fluid

  18. Distillation of shale and other bituminous substances. [shale granules wetted, mixed with lime, heated; sulfur recovered

    Energy Technology Data Exchange (ETDEWEB)

    Noad, J

    1912-09-23

    A process is described for the treatment of shale and other bituminous substances containing sulfur and recovering desulfurized distillates. The process consists of first grinding the shale and mixing the granules obtained with a convenient liquid. The shale granules coated or covered with liquid and mixed with slacked lime are fed into a retort with a series of steps or their equivalent, made to descend, step by step, in such manner that they are continually agitated and heated. The volatile constituents escape through the coating or sheath of lime and are carried away at the upper part of the retort to a convenient condensing apparatus, the sulfur being retained by the sheath of lime and is discharged at the bottom of the retort with the spent shale and other impurities.

  19. Distillation of bituminous shale

    Energy Technology Data Exchange (ETDEWEB)

    Seguin, M

    1875-02-16

    The retort with its accessories constitutes a distillation apparatus for shale composed of a cylindrical, vertical, fixed, tubular, and of ring form metal retort. Also it is comprised of a special hearth of large dimensions in the form of a circular pocket receiving from the retort as heating agent the distilled shale and emitting by radiation the heat that makes the distillation apparatus for the shale act.

  20. First American record of the Jurassic ichnogenus Deltapodus and a review of the fossil record of stegosaurian footprints

    DEFF Research Database (Denmark)

    Milàn, Jesper; Chiappe, Luis M

    2009-01-01

    We describe the first American stegosaur track of the ichnospecies Deltapodus brodricki, collected in the Upper Jurassic Morrison Formation of San Juan County, southeastern Utah, United States. The track is preserved as a natural cast on the underside of a slab of fluvial sandstone and consists o...... and highlights the similarities between the Late Jurassic dinosaur faunas of North America and those of Western Europe....

  1. Dinosaur tracks in Lower Jurassic coastal plain sediments (Sose Bugt Member, Rønne Formation) on Bornholm, Denmark

    DEFF Research Database (Denmark)

    Clemmensen, Lars B; Milàn, Jesper; Pedersen, Gunver K

    2014-01-01

    Fluvial palaeochannels of coastal plain sediments of the Lower Jurassic Sose Bugt Member of the Rønne Formation exposed in the coastal cliffs at Sose Bugt, Bornholm, contain abundant dinosaur or other large vertebrate tracks in the form of deformation structures exposed in vertical section...... track. Contemporary Upper Triassic – Lower Jurassic strata from southern Sweden and Poland contain a diverse track fauna, supporting our interpretation. This is the earliest evidence of dinosaur activity in Denmark....

  2. Barnett shale completions

    Energy Technology Data Exchange (ETDEWEB)

    Schein, G. [BJ Services, Dallas, TX (United States)

    2006-07-01

    Fractured shales yield oil and gas in various basins across the United States. A map indicating these fractured shale source-reservoir systems in the United States was presented along with the numerous similarities and differences that exist among these systems. Hydrocarbons in the organic rich black shale come from the bacterial decomposition of organic matter, primary thermogenic decomposition of organic matter or secondary thermogenic cracking of oil. The shale may be the reservoir or other horizons may be the primary or secondary reservoir. The reservoir has induced micro fractures or tectonic fractures. This paper described the well completions in the Barnett Shale in north Texas with reference to major players, reservoir properties, mineralogy, fluid sensitivity, previous treatments, design criteria and production examples. The Barnett Shale is an organic, black shale with thickness ranging from 100 to 1000 feet. The total organic carbon (TOC) averages 4.5 per cent. The unit has undergone high rate frac treatments. A review of the vertical wells in the Barnett Shale was presented along with the fracture treatment schedule and technology changes. A discussion of refracturing opportunities and proppant settling and transport revealed that additional proppant increases fluid recovery and enhances production. Compatible scale inhibitors and biocides can be beneficial. Horizontal completions in the Barnett Shale have shown better results than vertical wells, as demonstrated in a production comparison of 3 major horizontal wells in the basin. tabs., figs.

  3. Oil shale technology

    International Nuclear Information System (INIS)

    Lee, S.

    1991-01-01

    Oil shale is undoubtedly an excellent energy source that has great abundance and world-wide distribution. Oil shale industries have seen ups and downs over more than 100 years, depending on the availability and price of conventional petroleum crudes. Market forces as well as environmental factors will greatly affect the interest in development of oil shale. Besides competing with conventional crude oil and natural gas, shale oil will have to compete favorably with coal-derived fuels for similar markets. Crude shale oil is obtained from oil shale by a relatively simple process called retorting. However, the process economics are greatly affected by the thermal efficiencies, the richness of shale, the mass transfer effectiveness, the conversion efficiency, the design of retort, the environmental post-treatment, etc. A great many process ideas and patents related to the oil shale pyrolysis have been developed; however, relatively few field and engineering data have been published. Due to the vast heterogeneity of oil shale and to the complexities of physicochemical process mechanisms, scientific or technological generalization of oil shale retorting is difficult to achieve. Dwindling supplied of worldwide petroleum reserves, as well as the unprecedented appetite of mankind for clean liquid fuel, has made the public concern for future energy market grow rapidly. the clean coal technology and the alternate fuel technology are currently of great significance not only to policy makers, but also to process and chemical researchers. In this book, efforts have been made to make a comprehensive text for the science and technology of oil shale utilization. Therefore, subjects dealing with the terminological definitions, geology and petrology, chemistry, characterization, process engineering, mathematical modeling, chemical reaction engineering, experimental methods, and statistical experimental design, etc. are covered in detail

  4. Shale oil. II. Gases from oil shale

    Energy Technology Data Exchange (ETDEWEB)

    McKee, R H; Manning, P D.V.

    1927-01-01

    Oil shale (from Colorado) was pyrolyzed, and the gaseous products obtained were studied. The organic material present in oil shale contains carboxyl groups that lose carbon dioxide during pyrolysis before the formation of soluble bitumen. Nitrogen was evolved as ammonia in two stages and was not continuous. The first evolution was from loosely combined nitrogen structures, whereas the second was from more stable forms. No hydrocarbons were present as such in the kerogen. The gaseous products from oil-shale pyrolysis were similar to those obtained by distillation of colophony, amber, coal, and wood. This places the kerogen of the oil shale in the same series of carbonaceous substances as those from which coals are formed. Kerogen appeared to be decomposed in three steps; namely, to insoluble bitumen, to soluble bitumen, and to oil (gas evolution accompanied each step). Its low solubility and the character of its pyrolytic gas indicated that kerogen is largely a resinous residue from vegetation of the past era and may have been formed by the tranportation of coal-forming organic debris to inland salty lakes or carried to the sea by clay-laden waters. The salt water and the natural settling action precipitated the clay and organic matter in an almost homogeneous deposit. Oil shales have existed to the present time because they have not been subjected to high pressures or elevated temperatures that would have changed them to petroleum.

  5. Geologic framework for the assessment of undiscovered oil and gas resources in sandstone reservoirs of the Upper Jurassic-Lower Cretaceous Cotton Valley Group, U.S. Gulf of Mexico region

    Science.gov (United States)

    Eoff, Jennifer D.; Dubiel, Russell F.; Pearson, Ofori N.; Whidden, Katherine J.

    2015-01-01

    The U.S. Geological Survey (USGS) is assessing the undiscovered oil and gas resources in sandstone reservoirs of the Upper Jurassic–Lower Cretaceous Cotton Valley Group in onshore areas and State waters of the U.S. Gulf of Mexico region. The assessment is based on geologic elements of a total petroleum system. Four assessment units (AUs) are defined based on characterization of hydrocarbon source and reservoir rocks, seals, traps, and the geohistory of the hydrocarbon products. Strata in each AU share similar stratigraphic, structural, and hydrocarbon-charge histories.

  6. Environmental baselines: preparing for shale gas in the UK

    Science.gov (United States)

    Bloomfield, John; Manamsa, Katya; Bell, Rachel; Darling, George; Dochartaigh, Brighid O.; Stuart, Marianne; Ward, Rob

    2014-05-01

    Groundwater is a vital source of freshwater in the UK. It provides almost 30% of public water supply on average, but locally, for example in south-east England, it is constitutes nearly 90% of public supply. In addition to public supply, groundwater has a number of other uses including agriculture, industry, and food and drink production. It is also vital for maintaining river flows especially during dry periods and so is essential for maintaining ecosystem health. Recently, there have been concerns expressed about the potential impacts of shale gas development on groundwater. The UK has abundant shales and clays which are currently the focus of considerable interest and there is active research into their characterisation, resource evaluation and exploitation risks. The British Geological Survey (BGS) is undertaking research to provide information to address some of the environmental concerns related to the potential impacts of shale gas development on groundwater resources and quality. The aim of much of this initial work is to establish environmental baselines, such as a baseline survey of methane occurrence in groundwater (National methane baseline study) and the spatial relationships between potential sources and groundwater receptors (iHydrogeology project), prior to any shale gas exploration and development. The poster describes these two baseline studies and presents preliminary findings. BGS are currently undertaking a national survey of baseline methane concentrations in groundwater across the UK. This work will enable any potential future changes in methane in groundwater associated with shale gas development to be assessed. Measurements of methane in potable water from the Cretaceous, Jurassic and Triassic carbonate and sandstone aquifers are variable and reveal methane concentrations of up to 500 micrograms per litre, but the mean value is relatively low at documented in the range 2km. The geological modelling process will be presented and discussed

  7. Origin of oil shales

    Energy Technology Data Exchange (ETDEWEB)

    Weeks, W G

    1923-01-01

    The theory by Jones was questioned. Oil shales do not contain partly decomposed vegetable matter, and, where particles of vegetation are identified, they do not prove that kerogen was formed in its place. Some shales do contain free oil that can be extracted with solvents.

  8. Chemical aspects of shale and shale oils

    Energy Technology Data Exchange (ETDEWEB)

    Hackford, J E

    1922-01-01

    To prove that the kerogen in oil shale is a form of bitumen, several experiments were made with oil shale and a heavy asphaltic oil mixed with fuller's earth. When distilled, both the oil shale and asphalt-impregnated fuller's earth yielded paraffin oil, wax, and hydrogen sulfide (if sulfur was present). Both yielded ammonia if nitrogen was present. The organic material in each was partly isolated by extraction with pyridine and appeared to be the same. Oil shale is a marl that was saturated with oil or through which oil has passed or filtered. The insolubilities of its organic compounds are due to a slightly elevated temperature for a prolonged period and to the retaining effect exerted by the finely divided marl. The marl exerted a selective action on the oil and absorbed the asphaltum, sulfur, and nitrogen compounds from the oil. The class of oil evolved from a shale depended on the nature of the original compounds absorbed. Asphaltenes obtained from crude oil by precipitation with ethyl ether produced distillation products of water, hydrogen sulfide, ammonia, oil, wax, and a carbonaceous residue. Water was formed by decomposition of oxyasphaltenes and hydrogen sulfide by decomposition of thioasphaltenes. Ammonia was evolved during decomposition if lime was present, but if there was not sufficient free lime present, pyridine and pyrrole derivatives were redistilled as such. The oil and wax that resulted from the dry distillation were true decomposition products and equaled about 60 weight-percent of the asphaltenes. The oil and wax content of the mixture varied between 8 and 10 percent. The carbonaceous residue, which represented approximately 40 percent of the original asphaltene, was a decomposition product of the asphaltenes. Geologic comparisons of oil-shale deposits and oil-well fields were also made.

  9. Oil shale activities in China

    International Nuclear Information System (INIS)

    Peng, D.; Jialin, Q.

    1991-01-01

    China has abundant oil shale resources, of the Early Silurian to Neogene age, the most important being the Tertiary period. The proved oil shale reserves in Fushun amount to 3.6 billion t, in Maoming 4.1 billion t. In Fushun, oil shale is produced by open-pit mining as a byproduct of coal, in Maoming it is also mined in open pits, but without coal. In China, scale oil has been produced from oil shale for 60 years. Annual production of crude shale oil amounts to about 200 000 t. The production costs of shale oil are lower than the price of crude petroleum on the world market. China has accumulated the experience and technologies of oil shale retorting. The Fushun type retort has been elaborated, in which the latent and sensible heat of shale coke is well utilized. But the capacity of such retort is relatively small, therefore it is suitable for use in small or medium oil plants. China has a policy of steadily developing shale oil industry. China is conducting oil shale research and developing oil shale processing technology. Much attention is being pay ed to the comprehensive utilization of oil shale, shale oil, and to environmental problems. In China, oil shale is mostly used for producing shale by retorting, attention will also be paid to direct combustion for power generation. Great achievements in oil shale research have been made in the eighties, and there will be a further development in the nineties. (author), 12 refs., 3 tabs

  10. Stratigraphy and macrofauna of the Lower Jurassic (Toarcian) Marrat Formation, central Saudi Arabia

    Science.gov (United States)

    El-Sorogy, Abdelbaset S.; Gameil, Mohamed; Youssef, Mohamed; Al-Kahtany, Khaled M.

    2017-10-01

    The stratigraphy and macrofaunal content of the Lower Jurassic (Toarcian) Marrat Formation was studied at Khashm adh Dhibi, central Saudi Arabia. The studied succession is dominated by limestones and dolomites, with subordinate occurrences of sandstones, siltstones and claystones. The formation is highly fossiliferous with brachiopods, gastropods, bivalves, ammonites and echinoids, particularly the lower and upper members. Twenty nine species are identified, they include 7 species of brachiopods, 8 gastropods, 8 bivalves, 4 ammonites and 2 echinoids. Many of the identified fauna are correlated with Jurassic equivalents in Jordan, Italy, Morocco, Egypt and India. Three gastropod species: Globularia subumbilicata, Ampullospira sp., Purpuroidea peristriata and seven bivalve species: Palaeonucula lateralis, Chlamys (Radulopecten) fibrosa, Eligmus weiri, E.integer, E. asiaticus, Musculus somaliensis and Pholadomya orientalis were recognized for the first time in the Lower Jurassic deposits of Saudi Arabia.

  11. Common clay and shale

    Science.gov (United States)

    Virta, R.L.

    2000-01-01

    Part of the 1999 Industrial Minerals Review. The clay and shale market in 1999 is reviewed. In the U.S., sales or use of clay and shale increased from 26.4 million st in 1998 to 27.3 million st in 1999, with an estimated 1999 value of production of $143 million. These materials were used to produce structural clay products, lightweight aggregates, cement, and ceramics and refractories. Production statistics for clays and shales and for their uses in 1999 are presented.

  12. Triassic-Jurassic pteridosperms of Australasia: speciation, diversity and decline

    Energy Technology Data Exchange (ETDEWEB)

    Pattemore, G. A.; Rigby, J. F.; Playford, G.

    2015-07-01

    Pteridosperms are preserved abundantly in the Gondwanan Triassic, with many species exhibiting consider- able morphological variation that has been attributed to a hybridization model of speciation. This is an improbable explanation given that hybridization is very rare in gymnosperms. Allopatric speciation resulting from geographic and climatic provincialism is a more likely explanation for the morphological diversity which is well represented in Anisian Norian (Middle and Upper Triassic) floras of Australasia and elsewhere in Gondwana. Most specimens are distributed among three families: Umkomasiaceae, Peltaspermaceae and Matatiellaceae. These families, together with other possibly pteridospermous genera, are reviewed herein. Diversity in these families apparently declined by the Rhaetian and they did not persist into the Gondwanan post-Triassic. Australasian post-Triassic strata contain remarkably different floral assemblages to those of the Triassic. No fructifications are clearly pteridospermous and no remains show any obvious relationship with pteridosperms of the Gondwanan Triassic. Caytonialean fructifications are not known in Australasian strata; however, associated foliage has been reported from the Eastern Gondwanan Upper Triassic through Middle Jurassic including Australia. Much fern-like foliage, claimed to be pteridospermous from the Lower Jurassic through Eocene of Eastern Gondwana, lacks supporting evidence of such affiliation. (Author)

  13. Revised models for hydrocarbon generation, migration and accumulation in Jurassic coal measures of the Turpan basin, NW China

    Energy Technology Data Exchange (ETDEWEB)

    Li Maowen; Stasiuk, L.D. [Geological Survey of Canada, Calgary, Alberta (Canada); Bao Jianping [Jianghan Petroleum University, Hubei (China); Lin, R. [Petroleum University (Beijing), Changping (China); Yuan Mingsheng [PetroChina Tu-Ha Oilfield Company, Xingjiang (China)

    2001-07-01

    Whether or not the Lower-Middle Jurassic coal measures in the Turpan basin of NW China have generated commercial quantities of liquid petroleums is a problem of considerable importance that remains contentious as it has not yet been resolved unequivocally. This study provides evidence against the Jurassic humic coals as the only major source for the oils discovered in the Taibei depression of this basin and suggests additional significant contributions from the Upper Permian and Middle-Lower Jurassic lacustrine source rocks. The Carboniferous-Permian marine source rocks may have been important also in limited locations along the major basement faults. Molecular and petrographic data indicate that the majority of the Middle Jurassic strata are currently immature or marginally mature with respect to hydrocarbon generation. Within the major depocenters, the Middle-Lower Jurassic coal-bearing strata of the Baodaowan and Xishanyao formations has reached the conventional oil window (i.e. with vitrinite reflectance >0.7 per cent Ro). Pre-Jurassic (Upper Permian in particular) derived hydrocarbons appear to be widespread in extracts of fractured Jurassic coal and fine-grained rocks. Large differences have been observed in the absolute concentrations of biomarker compounds in rock extracts of various source intervals. Thus, 'coaly' biomarker signatures of the oils most likely resulted from mixing and migration contamination when hydrocarbons derived from mature source rocks migrated up through highly fractured coal seams along deep-seated faults. In addition to conventional exploration targets, revised petroleum generation and accumulation models predict that the focus in the Turpan basin should also include deep structures within the Carboniferous-Permian strata and subtle, low magnitude anticlines and stratigraphic traps within thr Triassic-Jurassic sections. (author)

  14. Improvements in shale retorts

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, A C

    1915-05-01

    This invention has reference to shale retorts and particularly related to the discharge of the spent material from the bottom of retorts or gas producers for the destructive distillation of shale, coal or other bituminous substances. It consists in the combination of a blade and means for rocking the same, a bottom piece or table, holes or slots in the same, a passage in the front brick-work of the retort, and a hopper with discharge doors.

  15. Intergrated study of the Devonian-age black shales in eastern Ohio. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Gray, J.D.; Struble, R.A.; Carlton, R.W.; Hodges, D.A.; Honeycutt, F.M.; Kingsbury, R.H.; Knapp, N.F.; Majchszak, F.L.; Stith, D.A.

    1982-09-01

    This integrated study of the Devonian-age shales in eastern Ohio by the Ohio Department of Natural Resources, Division of Geological Survey is part of the Eastern Gas Shales Project sponsored by the US Department of Energy. The six areas of research included in the study are: (1) detailed stratigraphic mapping, (2) detailed structure mapping, (3) mineralogic and petrographic characterization, (4) geochemical characterization, (5) fracture trace and lineament analysis, and (6) a gas-show monitoring program. The data generated by the study provide a basis for assessing the most promising stratigraphic horizons for occurrences of natural gas within the Devonian shale sequence and the most favorable geographic areas of the state for natural gas exploration and should be useful in the planning and design of production-stimulation techniques. Four major radioactive units in the Devonian shale sequence are believed to be important source rocks and reservoir beds for natural gas. In order of potential for development as an unconventional gas resource, they are (1) lower and upper radioactive facies of the Huron Shale Member of the Ohio Shale, (2) upper Olentangy Shale (Rhinestreet facies equivalent), (3) Cleveland Shale Member of the Ohio Shale, and (4) lower Olentangy Shale (Marcellus facies equivalent). These primary exploration targets are recommended on the basis of areal distribution, net thickness of radioactive shale, shows of natural gas, and drilling depth to the radioactive unit. Fracture trends indicate prospective areas for Devonian shale reservoirs. Good geological prospects in the Devonian shales should be located where the fracture trends coincide with thick sequences of organic-rich highly radioactive shale.

  16. Geologic models and evaluation of undiscovered conventional and continuous oil and gas resources: Upper Cretaceous Austin Chalk

    Science.gov (United States)

    Pearson, Krystal

    2012-01-01

    The Upper Cretaceous Austin Chalk forms a low-permeability, onshore Gulf of Mexico reservoir that produces oil and gas from major fractures oriented parallel to the underlying Lower Cretaceous shelf edge. Horizontal drilling links these fracture systems to create an interconnected network that drains the reservoir. Field and well locations along the production trend are controlled by fracture networks. Highly fractured chalk is present along both regional and local fault zones. Fractures are also genetically linked to movement of the underlying Jurassic Louann Salt with tensile fractures forming downdip of salt-related structures creating the most effective reservoirs. Undiscovered accumulations should also be associated with structure-controlled fracture systems because much of the Austin that overlies the Lower Cretaceous shelf edge remains unexplored. The Upper Cretaceous Eagle Ford Shale is the primary source rock for Austin Chalk hydrocarbons. This transgressive marine shale varies in thickness and lithology across the study area and contains both oil- and gas-prone kerogen. The Eagle Ford began generating oil and gas in the early Miocene, and vertical migration through fractures was sufficient to charge the Austin reservoirs.

  17. Marcellus shale gas potential in the southern tier of New York

    Energy Technology Data Exchange (ETDEWEB)

    Faraj, B. [Talisman Energy Inc., Calgary, AB (Canada); Duggan, J. [Hunt Oil Canada, Calgary, AB (Canada)

    2008-07-01

    Marcellus shale is a significant, underexplored, shale gas target in the Appalachian Basin. Gas-in-place estimates in the Marcellus shale range from 200 to 100 billion cubic feet (bcf). The Devonian shales have favorable attributes such as high total organic content (TOC), high gas content, favorable mineralogy and over-pressured. Land owned by Fortuna Energy in the northern Appalachian Basin may contain significant shale gas with unrisked gas-in-place in excess of 10 trillion cubic feet. Unlocking the true shale gas potential requires innovative drilling and completion techniques. This presentation discussed Marcellus shale gas potential in the southern tier and a test program being conducted by Fortuna to test the potential. Several photographs were shown, including Taughannock Falls, Finger Lakes and the Ithaca Shale, Sherburne Sandstone, and Geneseo Shale; two orthogonal fracture sets in the Upper Devonian Geneseo Shale; and two orthogonal fracture sets in the Upper Devonian Rocks, near Corning, New York. Figures that were presented included the supercontinent Pangaea in the early Triassic; undiscovered gas resources in the Appalachian Basin; stratigraphy; and total gas production in New York since 1998. Fortuna's work is ongoing in the northern Appalachian Basin. tabs., figs.

  18. Sorption of cesium, strontium, and technetium onto organic-extracted shales

    International Nuclear Information System (INIS)

    Ho, P.C.

    1992-01-01

    The sorption of Cs(I), Sr(II), and Tc(VII) onto organic-extracted shales from synthetic brine groundwaters and from 0.03-M NaHCO 3 solution under oxid conditions at room temperature has been studied. The shale samples used in this study were Pumpkin Valley, Upper Dowelltown, Pierre and Green River Formation Shales. The organic content of these shales ranges from less than 2 wt% to 13 wt%. Soxhlet extraction with chloroform and a mixture of chloroform and methanol removed 0.07 to 5.9 wt% of the total organic matter from these shales. In comparison with the results of sorption of these three metal ions onto the corresponding untreated shales, it was observed that there were moderate to significant sorption decreases of Cs(I) and Sr(II) on all four organic-extracted shale samples and moderate sorption decrease of Tc(VII) on the organic-extracted Pumpkin Valley, Pierre, and Green River Shale samples, but only moderate sorption increases of Tc(VII) on the organic-extracted Upper Dowelltown Shale samples from the brine groundwaters. Nevertheless, sorption of Cs(I), Sr(II), and Tc(VII) on all four organic-extracted shale samples from the bicarbonate solution in most cases did not show a consistent pattern. (orig.)

  19. Mineralogical and geochemical characterization of the Jurassic coal from Egypt

    Energy Technology Data Exchange (ETDEWEB)

    Baioumy, H.M. [Central Metallurgical Research and Development Institute, Cairo (Egypt)

    2009-06-15

    The Jurassic coal deposit in the Maghara area, Sinai, Egypt contains at least 11 coal seams of lenticular shape. The thickness of the main coal seams ranges from 130 cm to 2 m and are underlain and overlain by thin black shale beds. Mineralogical analysis indicated that this coal is characterized by low mineral matter with traces of quartz in some samples. However, coal ash is made up of quartz with traces of calcite, anhydrite, and hematite. Analysis of coal rank parameters indicated that the Maghara coal can be classified as medium volatile bituminous coal. The high sulfur contents and the relatively high proportion of pyritic sulfur suggest a possible marine transgression after the deposition of precursor peat. This interpretation is supported by the relatively high B contents. The relatively high Ge in the Maghara coal could be attributed to an infiltration of Ge enriched water from the surrounding siliceous sediments probably during diagenesis. The high Au contents were contributed to an Au-rich provenance of the ash contents of this coal. Rare earth elements geochemistry indicated low concentrations of these elements with slight enrichment of light rare earth elements (LREEs), slight negative Eu anomaly, and relatively flat heavy rare earth elements (HREEs) patterns. The low contents of trace and rare earth elements, particularly those with environmental relevance, compared to the usual concentration ranges in worldwide coal gives an advantage for this coal.

  20. Process for oil shale retorting

    Science.gov (United States)

    Jones, John B.; Kunchal, S. Kumar

    1981-10-27

    Particulate oil shale is subjected to a pyrolysis with a hot, non-oxygenous gas in a pyrolysis vessel, with the products of the pyrolysis of the shale contained kerogen being withdrawn as an entrained mist of shale oil droplets in a gas for a separation of the liquid from the gas. Hot retorted shale withdrawn from the pyrolysis vessel is treated in a separate container with an oxygenous gas so as to provide combustion of residual carbon retained on the shale, producing a high temperature gas for the production of some steam and for heating the non-oxygenous gas used in the oil shale retorting process in the first vessel. The net energy recovery includes essentially complete recovery of the organic hydrocarbon material in the oil shale as a liquid shale oil, a high BTU gas, and high temperature steam.

  1. Process for extracting oil shale

    Energy Technology Data Exchange (ETDEWEB)

    1920-08-22

    A process is described for recovering bituminous material from oil shale, characterized in that the oil shale is extracted with wood spirits oil (byproduct of woodspirit rectification), if necessary in admixture with other solvents in the cold or the hot.

  2. Apparatus for treating bituminous shale

    Energy Technology Data Exchange (ETDEWEB)

    1942-11-24

    A method is given of transforming finely crushed bituminous shale, for instance of maximum particle size of about 5 mm, into balls, nodules, or similar shapes, in which the shale to be treated is passed in the form of lumps through a rotary drum. The finely crushed shale with a higher content of moisture is brought into contact with finely crushed shale of a lower content of moisture, and thereby serves as kernel material during the formation of the nodules or similar shapes.

  3. Shale oil combustion

    International Nuclear Information System (INIS)

    Al-dabbas, M.A.

    1992-05-01

    A 'coutant' carbon steel combustion chamber cooled by water jacket was conslructed to burn diesel fuel and mixlure of shale oil and diesel fuels. During experimental work nir fuel ratio was determined, temperaturces were measured using Chromel/ Almel thermocouple, finally the gasous combustion product analysis was carricd out using gas chromatograph technique. The constructed combustion chamber was operating salisfactory for several hours of continous work. According to the measurements it was found that: the flame temperature of a mixture of diesel and shale oil fuels was greater than the flame temperature of diesel fuel. and the sulfer emissious of a mixture of diesel and shale oil fuels was higher than that of diesel fuel. Calculation indicated that the dry gas energy loss was very high and the incomplete combustion energy loss very small. (author). 23 refs., 35 figs

  4. Oil shale highlights

    International Nuclear Information System (INIS)

    1994-01-01

    The low prices of crude oil have continued to retard the commercial development of oil shale and other syn fuels. Although research funds are more difficult to find, some R and D work by industry, academia, and governmental agencies continues in the United States and in other parts of the world. Improvements in retorting technology, upgrading oil-shale feedstock, and developing high-value niche-market products from shale oil are three notable areas of research that have been prominent for the past several years. Although the future prices of conventional crude cannot be predicted, it seems evident that diminishing supplies and a burgeoning world population will force us to turn to alternate fossil fuels as well as to cleaner sources of non-fossil energy. (author)

  5. Shale oil combustion

    Energy Technology Data Exchange (ETDEWEB)

    Al-dabbas, M A

    1992-05-01

    A `coutant` carbon steel combustion chamber cooled by water jacket was conslructed to burn diesel fuel and mixlure of shale oil and diesel fuels. During experimental work nir fuel ratio was determined, temperaturces were measured using Chromel/ Almel thermocouple, finally the gasous combustion product analysis was carricd out using gas chromatograph technique. The constructed combustion chamber was operating salisfactory for several hours of continous work. According to the measurements it was found that: the flame temperature of a mixture of diesel and shale oil fuels was greater than the flame temperature of diesel fuel. and the sulfer emissious of a mixture of diesel and shale oil fuels was higher than that of diesel fuel. Calculation indicated that the dry gas energy loss was very high and the incomplete combustion energy loss very small. (author). 23 refs., 35 figs.

  6. Microfacies and microfossils in Upper Jurassic limestones from Cheile Turenilor

    Directory of Open Access Journals (Sweden)

    Emanoil Săsăran

    2001-09-01

    Full Text Available In the Cheile Turenilor (Tureni Gorges area, a carbonate succession about 150 m thick developed on top of island arc magmatites. It mainly consist of gravity - induced deposits (debris flows, mass flows and grain flows. Coral, sponges and stromatoporoid bioconstructions are associated. Microbolites play an important role, as binders of the intraclastic rudstones/ grainstones facies, as well as of the incorporated corals, sponges, stromatoporoids, bryozoans, molluscs.

  7. Faunes du Jurassique supérieur dans les séries pélagiques de l'escarpement de Malte (Mer Ionienne. Implications paléogéographiques Upper Jurassic Fauna in the Pelagic Series of the Malta Escarpment (Lonian Sea. Paleogeographic Implications

    Directory of Open Access Journals (Sweden)

    Enay R.

    2006-11-01

    Full Text Available Au cours d'une campagne de plongée sur les escarpements qui bordent le bassin Ionien profond, des roches sédimentaires d'âge jurassique supérieur ont pu être récoltées dans l'escarpement de Malte, associées à des coulées de pillow-lavas. Les faunes d'Ammonites, typiquement mésogéennes, indiquent des âges oxfordien et tithonique. Elles peuvent correspondre à un milieu de dépôt profond. Les foraminifères recueillis dans les niveaux équivalents, riches en radiolaires, sclérites d'holothuries, fragments d'aptychus et rares Ostracodes, indiquent un âge oxfordien au sens large et un milieu de dépôt relativement profond. Cette série, relativement condensée et profonde, est comparable aux séries du même âge connues en Sicile. Elle s'oppose aux séries de calcaires de plate-forme néritiques du Trias-Lias inférieur qui constituent la base de la coupe. II y a donc eu un changement radical de milieu de sédimentation entre le Lias et le Callovo-Oxfordien, accompagné d'une distension révélée par un magmatisme important. During a diving campaing along the escarpments bordering the deep lonian Basin, Upper Jurassic sedimentary rocks were gathered from the Malta escarpment, associated with pillow-lava. Typically Mesogean ammonite fauna indicate Oxfordian and Tithonian ages. They correspond to a relatively deep deposition environment. The Foraminifers gathered in the equivalent levels, which proved to be rich in radiolarians, holothuroid sclerites, aptychus fragments and sparse ostracodes, indicate an Oxfordian age and a relatively deep deposition environnent. This relatively condensed and deep series can be compared with series of the same age known in Sicily. It is opposed to the Lower Triassic-Lias neritic platform limestone series making up the bottom of the section. A radical change in sedimentation thus occured between the Lias and the Callovo-Oxfordain, accompanied by a distension revealed by extensive magmatism.

  8. Shale gas - Risks and stakes

    International Nuclear Information System (INIS)

    Parks, Olivier

    2014-01-01

    This book aims at exploring all aspects of the shale gas issue: geological data, environmental impacts, financial aspects and economical impacts of shale gas exploitation. It compares the available information with the field reality and defeats the dogmatic mirages. The research and compilation work carried out by the author make this book a reference in the domain of shale gas exploitation

  9. Process of briquetting fine shale

    Energy Technology Data Exchange (ETDEWEB)

    Kraemer, J

    1943-05-05

    A process is described for the preparation of briquetts of fine bituminous shale, so-called Mansfield copper shale, without addition of binding material, characterized in that the fine shale is warmed to about 100/sup 0/C and concurrently briquetted in a high-pressure rolling press or piece press under a pressure of 300 to 800 kg/cm/sup 2/.

  10. Treating oil shale

    Energy Technology Data Exchange (ETDEWEB)

    Dolbear, S H

    1921-01-04

    Oil shale is treated for the separation of the valuable organic compounds, with a view to economy in subsequent destructive distillation, by grinding to powder, mixing with water to form a pulp, adding a small quantity of an oil liquid and aerating the mixture to form a froth containing the organic compounds. If the powdered shale contains sufficient free oil, the addition of oil to the pulp may be dispensed with. In some cases an electrolyte such as sulfuric acid may be added to the pulp.

  11. Treating bituminous shale

    Energy Technology Data Exchange (ETDEWEB)

    Ginet, J H

    1921-03-09

    Apparatus for the treatment of bituminous shales is described wherein a number of separate compartments are arranged in alignment and communicate with each other near the bottom thereof, each of the compartments being provided with outlets for the gases evolved therein, while agitators are arranged in each of the compartments, each agitator being composed of a number of shovels which sweep up the comminuted shale at their forward end and discharge it at their rearward end into the path of the next adjacent agitator.

  12. Origin of oil shale

    Energy Technology Data Exchange (ETDEWEB)

    Cunningham-Craig, E H

    1915-01-01

    Kerogen was believed to be formed by the inspissation of petroleum. During this process nitrogen and sulfur compounds were concentrated in the most inspissated or weathered products. At a certain stage, reached gradually, the organic matter became insoluble in carbon-disulfide and ceased to be a bitumen. Oil shale was formed by the power of certain clays or shales to absorb inspissated petroleum, particularly unsaturated hydrocarbons. This adsorption apparently depended on the colloid content of the argillaceous rock. This rock retained these impregnated petroleum residues long after porous sandstones in the vicinity had lost all traces of petroleum by weathering and leaching.

  13. Organic material of the Messel oil shales

    Energy Technology Data Exchange (ETDEWEB)

    Jankowski, B.; Littke, R.

    1986-05-01

    According to chemism, the Messel oil shales belong to the Kerogen type II, formed by algae with additions of huminite detritus, i.e. residues of higher plants. This has been confirmed by the organo-petrographic studies reported. The oil shale deposits are characterised by their content of organic materials, the occurrence of a cream-coloured inertinite maceral, and of siderite. Hence, two facies can be clearly discriminated, the lower one containing relatively much organic material and the cream-coloured inertinite, but no siderite, and the upper facies exhibiting just the opposite. As the detritus is finely grained and quite uniform in content of huminite and silicate material, and only few spores and pollen have been found, there is reason to assume that the two facies represent sediments formed far from the border of the lake.

  14. Apparatus for decomposing shale

    Energy Technology Data Exchange (ETDEWEB)

    Gislain, M

    1865-06-20

    The apparatus is designed to fulfill the three following conditions: (1) complete extraction of the mineral oil, by avoiding partial decomposition; (2) purification of the said oil from products formed in the decomposition of the shale; (3) breaking down of the said oil into more products of different density. The separation of the heavy and bituminous products is claimed.

  15. Organic geochemistry: Effects of organic components of shales on adsorption: Progress report

    International Nuclear Information System (INIS)

    Ho, P.C.

    1988-11-01

    The Sedimentary Rock Program at the Oak Ridge National Laboratory is investigating shale to determine its potential suitability as a host rock for the disposal of high-level radioactive wastes (HLW). The selected shales are Upper Dowelltown, Pierre, Green River Formation, and two Conasauga (Nolichucky and Pumpkin Valley) Shales, which represent mineralogical and compositional extremes of shales in the United States. According to mineralogical studies, the first three shales contain 5 to 13 wt % of organic matter, and the two Conasauga Shales only contain trace amounts (2 wt %) of organic matter. Soxhlet extraction with chloroform and a mixture of chloroform and methanol can remove 0.07 to 5.9 wt % of the total organic matter from these shales. Preliminary analysis if these organic extracts reveals the existence of organic carboxylic acids and hydrocarbons in these samples. Adsorption of elements such as Cs(I), Sr(II) and Tc(VII) on the organic-extracted Upper Dowelltown, Pierre, green River Formation and Pumpkin Valley Shales in synthetic groundwaters (simulating groundwaters in the Conasauga Shales) and in 0.03-M NaHCO 3 solution indicates interaction between each of the three elements and the organic-extractable bitumen. 28 refs., 8 figs., 10 tabs

  16. Process of recovering shale oil

    Energy Technology Data Exchange (ETDEWEB)

    1949-01-17

    A process is disclosed for recovering oil from shale rock by means of channels cut in the shale deposit, to which heat is carried for warming the shale mass and which are separated from the fume channels formed in the shale by parts of the shale rock, characterized in that heating elements are put down in the heating channels, which occupy less cross section than these channels, and in the so-formed space between the channel wall and the heating element a filling is placed, which facilitates heat transfer between the heating element and the shale and simultaneously prevents a streaming of the oily product gasified out of the shale from working into the heating element and stopping it.

  17. Late Jurassic low latitude of Central Iran: paleogeographic and tectonic implications

    Science.gov (United States)

    Mattei, Massimo; Muttoni, Giovanni; Cifelli, Francesca

    2014-05-01

    The individual blocks forming present-day Central Iran are now comprised between the Zagros Neo-Tethys suture to the south and the Alborz Palaeo-Tethys suture to the north. At the end of the Palaeozoic, the Iranian blocks rifted away from the northern margin of Gondwana as consequence of the opening of the Neo-Tethys, and collided with Eurasia during the Late Triassic, giving place to the Eo-Cimmerian orogeny. From then on, the Iranian block(s) should have maintained European affinity. Modern generations of apparent polar wander paths (APWPs) show the occurrence in North American and African coordinates of a major and rapid shift in pole position (=plate shift) during the Middle-Late Jurassic. This so-called monster polar shift is predicted also for Eurasia from the North Atlantic plate circuit, but Jurassic data from this continent are scanty and problematic. Here, we present paleomagnetic data from the Kimmeridgian-Tithonian (Upper Jurassic) Garedu Formation of Iran. Paleomagnetic component directions of primary (pre-folding) age indicate a paleolatitude of deposition of 10°N ± 5° that is in excellent agreement with the latitude drop predicted for Iran from APWPs incorporating the Jurassic monster polar shift. We show that paleolatitudes calculated from these APWPs, used in conjunction with simple zonal climate belts, better explain the overall stratigraphic evolution of Iran during the Mesozoic.

  18. TRANSITION FROM CARBONATE PLATFORM TO PELAGIC DEPOSITION (MID JURASSIC- LATE CRETACEOUS, VOURINOS MASSIF, NORTHERN GREECE

    Directory of Open Access Journals (Sweden)

    NICOLAOS CARRAS

    2004-03-01

    Full Text Available A Jurassic- Cretaceous carbonate succession crops out along the Zyghosti Rema, Kozani (Northern Greece. The substratum consists of the ophiolitic succession of the Vourinos Massif (Pelagonian Domain: serpentinites tectonically overlain by basalts, with thin lenses of radiolarian cherts of middle Bathonian age. The contact with the overlying Jurassic limestones is tectonic. Eight informal units have been distinguished within the Mesozoic limestones, from the base upwards. (A bioclastic, intraclastic and oolitic packstone (Callovian- Oxfordian. (B bioclastic packstone and coral boundstone (Oxfordian . (C bioclastic and oncoidal wackestone with Clypeina jurassica (Oxfordian- Upper Kimmeridgian. (D (Upper Kimmeridgian- Portlandian: oncoidal packstone and rudstone (facies D1; intraclastic and bioclastic grainstone and packstone (facies D2; neptunian dykes with intraclastic and bioclastic wackestone and packstone filling (facies D3; neptunian dykes with Fe-Mn rich laterite filling and with pink silty filling of early Late Cretaceous age. An unconformity surface, due to emersion and erosion of the platform during the latest Jurassic- Early Cretaceous, is overlain by (E intraclastic, bioclastic packstone and grainstone (Cenomanian. (F massive body of debrites with coral, echinoderm, algae and rudist large clasts (facies F1 (Cenomanian; turbiditic beds of bioclastic, intraclastic and lithoclastic rudstone and grainstone (facies F2. (G thin bedded bioclastic mudstone and wackestone with planktonic foraminifers and radiolarians, alternating with turbiditic beds of bioclastic, intraclastic packstone and rudstone and with conglomeratic levels and slumped beds of the previous turbidites (upper Santonian- lower Campanian. (H: bioclastic packstone with planktonic foraminifers (facies H1 (lower Campanian - ?Maastrichtian; amalgamated turbiditic beds of bioclastic wackestone and packstone with planktonic foraminifers (facies H2; turbiditic beds of bioclastic

  19. The influence of soluble organic matter on shale reservoir characterization

    Directory of Open Access Journals (Sweden)

    Lei Pan

    2016-06-01

    Full Text Available Shale with a maturity within the “oil window” contains a certain amount of residual soluble organic matter (SOM. This SOM have an important influence on characterization of shale reservoir. In this study, two shale samples were collected from the Upper Permian Dalong Formation in the northwestern boundary of Sichuan Basin. Their geochemistry, mineral composition, and pore structure (surface area and pore volume were investigated before and after removing the SOM by means of extraction via dichloromethane or trichloromethane. The results show that the TOC, S1, S2, and IH of the extracted samples decrease significantly, but the mineral composition has no evident change as compared with their raw samples. Thus, we can infer that the original pore structure is thought to be unaffected from the extraction. The SOM occupies pore volume and hinders pores connectivity. The extraction greatly increases the surface area and pore volume of the samples. The residual SOM in the shale samples occur mainly in the micropores and smaller mesopores, and their occupied pore size range seems being constrained by the maturity. For the lower mature shale samples, the SOM is mainly hosted in organic pores that are less than 5 nm in size. For the middle mature shale samples, the micropores and some mesopores ranging between 2 and 20 nm in size are the main storage space for the SOM.

  20. Climate impact of potential shale gas production in the EU

    Energy Technology Data Exchange (ETDEWEB)

    Forster, D.; Perks, J. [AEA Technology plc, London (United Kingdom)

    2012-07-15

    Existing estimates of GHG emissions from shale gas production and available abatement options were used to obtain improved estimates of emissions from possible shale gas exploitation in the EU. GHG emissions per unit of electricity generated from shale gas were estimated to be around 4 to 8% higher than for electricity generated by conventional pipeline gas from within Europe. These additional emissions arise in the pre-combustion stage, predominantly in the well completion phase when the fracturing fluid is brought back to the surface together with released methane. If emissions from well completion are mitigated, through flaring or capture, and utilised, then this difference is reduced to 1 to 5%. The analysis suggests that the emissions from shale gas-based power generation (base case) are 2 to 10% lower than those from electricity generated from sources of conventional pipeline gas located outside of Europe (in Russia and Algeria), and 7 to 10% lower than those from electricity generated from LNG imported into Europe. However, under our 'worst case' shale gas scenario, where all flow back gases at well completion are vented, emissions from electricity generated from shale gas would be similar to the upper emissions level for electricity generated from imported LNG and for gas imported from Russia.

  1. Climate impact of potential shale gas production in the EU

    Energy Technology Data Exchange (ETDEWEB)

    Forster, D.; Perks, J. [AEA Technology plc, London (United Kingdom)

    2012-07-15

    Existing estimates of GHG emissions from shale gas production and available abatement options were used to obtain improved estimates of emissions from possible shale gas exploitation in the EU. GHG emissions per unit of electricity generated from shale gas were estimated to be around 4 to 8% higher than for electricity generated by conventional pipeline gas from within Europe. These additional emissions arise in the pre-combustion stage, predominantly in the well completion phase when the fracturing fluid is brought back to the surface together with released methane. If emissions from well completion are mitigated, through flaring or capture, and utilised, then this difference is reduced to 1 to 5%. The analysis suggests that the emissions from shale gas-based power generation (base case) are 2 to 10% lower than those from electricity generated from sources of conventional pipeline gas located outside of Europe (in Russia and Algeria), and 7 to 10% lower than those from electricity generated from LNG imported into Europe. However, under our 'worst case' shale gas scenario, where all flow back gases at well completion are vented, emissions from electricity generated from shale gas would be similar to the upper emissions level for electricity generated from imported LNG and for gas imported from Russia.

  2. Shale gas - uncertain destiny?

    International Nuclear Information System (INIS)

    Signoret, Stephane

    2013-01-01

    This article outlines that, even if it would be allowed, the exploitation of shale gas in France would need ten years to start, and no one can say what would be our needs then and what would be the situation of the gas market at that time. Even if the government decided to forbid hydraulic fracturing, there could be some opportunity for experimentation with a search for alternative technology. The article notices that risks associated with hydraulic fracturing and extraction of non conventional hydrocarbons, i.e. water pollution and consumption and land use, are variously perceived in different European countries (Germany, Romania, Poland) where important American actors are present (Chevron, Exxon) to exploit shale gases. In the USA, the economic profitability seems in fact to rapidly decrease

  3. Mineralogy and geochemistry of Mississippian and Lower Pennsylvanian black shales at the northern margin of the Variscan mountain belt (Germany and Belgium)

    Energy Technology Data Exchange (ETDEWEB)

    Rippen, D.; Uffmann, A.K.; Littke, R. [RWTH Aachen Univ. (Germany). Energy and Mineral Resources Group (EMR)

    2013-08-01

    Ongoing exploration on unconventional gas resources in Central Europe led to a focus of interest on Paleozoic black shale formations. The work presented here comprises diverse assessment-critical data of potentially economic black shale formations of the Carboniferous, including mineralogy, geochemical data, petrophysical data and geological parameters such as burial and thermal history. The sampled and investigated Paleozoic black shales are highly mature to overmature in terms of oil generation, although some gas generation potential remains. Especially the shales of the uppermost Mississippian (Upper Alum Shale/Chokier Formation) have high contents of organic carbon, are tens of meters thick and reached the gas window. Adjacent carbonates are often stained black and rich in solid bitumen, indicating a former oil impregnation of these reservoirs. Furthermore, the geochemical and petrophysical properties of the Upper Alum Shale and Chokier Formation black shales are similar to those of already producing shale gas plays like the Barnett shale in the USA. These shale sequences are enriched in silica, needed for enhanced fraccability performance at production stage. Although all hydrocarbon potential for the Mississippian shales is exhausted, a high retention potential of thermally generated gas is favored by thick overlying sequences of greywackes and shales in most of the investigated areas. Based on these observations, the Upper Alum Shale and the Chokier formation can be regarded as potential gas shale targets. Any exploration will have to take place north of the outcrop areas, because present-day Mississippian strata are completely eroded south of the studied outcrops. Most other Mississippian and Pennsylvanian black shales are relatively thin and are therefore not considered as primary targets for shale gas plays. (orig.)

  4. The Jurassic of North-East Greenland: Jurassic dinoflagellate cysts from Hochstetter Forland, North-East Greenland

    Directory of Open Access Journals (Sweden)

    Piasecki, Stefan

    2004-11-01

    Full Text Available Three sections in Hochstetter Forland, North-East Greenland, referred to the Jurassic Payer Dal and Bernbjerg Formations, have been analysed for dinoflagellate cysts. The dinoflagellate cysts,new finds of ammonites and previously recorded marine faunas form the basis for improved dating of the succession. The basal strata of the Payer Dal Formation at Kulhus is here dated as Late Callovian, Peltoceras athleta Chronozone, based on the presence of relatively abundant Limbicysta bjaerkei, Mendicodinium groenlandicum, Rhychoniopsis cladophora and Tubotuberella dangeardii in an otherwise poor Upper Callovian dinoflagellate assemblage. Ammoniteshave not been recorded from these strata. The upper Payer Dal Formation at Agnetesøelven is dated as Late Oxfordian, Amoeboceras glosense – Amoeboceras serratum Chronozones, based onthe presence of Sciniodinium crystallinum, together with Cribroperidinium granuligera and Stephanelytron sp. The age is in accordance with ammonites present in the uppermost part ofthe formation at Søndre Muslingebjerg. New ammonites in the Bernbjerg Formation at Agnetesøelven together with dinoflagellate cysts indicate an earliest Kimmeridgian age, Raseniacymodoce and Aulacostephanoides mutabilis Chronozones.The Upper Callovian dinoflagellate cysts from Hochstetter Forland belong to a local brackish to marginal marine assemblage, which only allows a fairly broad correlation to coeval assemblagesin central East Greenland. In contrast, the Oxfordian and Kimmeridgian assemblages are fully marine and can be correlated from Milne Land in central East Greenland via Hochstetter Forland to Peary Land in eastern North Greenland.

  5. Discovery of Jurassic ammonite-bearing series in Jebel Bou Hedma (South-Central Tunisian Atlas): Implications for stratigraphic correlations and paleogeographic reconstruction

    Science.gov (United States)

    Bahrouni, Néjib; Houla, Yassine; Soussi, Mohamed; Boughdiri, Mabrouk; Ali, Walid Ben; Nasri, Ahmed; Bouaziz, Samir

    2016-01-01

    Recent geological mapping undertaken in the Southern-Central Atlas of Tunisia led to the discovery of Jurassic ammonite-bearing series in the Jebel Bou Hedma E-W anticline structure. These series represent the Southernmost Jurassic rocks ever documented in the outcrops of the Tunisian Atlas. These series which outcrop in a transitional zone between the Southern Tunisian Atlas and the Chott basin offer a valuable benchmark for new stratigraphic correlation with the well-known Jurassic series of the North-South Axis of Central Tunisia and also with the Jurassic subsurface successions transected by petroleum wells in the study area. The preliminary investigations allowed the identification, within the most complete section outcropping in the center of the structure, of numerous useful biochronological and sedimentological markers helping in the establishment of an updated Jurassic stratigraphic framework chart of South-Western Tunisia. Additionally, the Late Jurassic succession documents syn-sedimentary features such as slumping, erosion and reworking of sediments and ammonite faunas that can be considered as strong witnesses of an important geodynamic event around the Jurassic-Cretaceous boundary. These stratigraphic and geodynamic new data make of the Jurassic of Jebel Bou Hedma a key succession for stratigraphic correlation attempt between Atlas Tunisian series and those currently buried in the Chott basin or outcropping in the Saharan platform. Furthermore, the several rich-ammonite identified horizons within the Middle and Upper Jurassic series constitute reliable time lines that can be useful for both paleogeographic and geodynamic reconstructions of this part of the North African Tethyan margin but also in the refinement of the potential migration routes for ammonite populations from the Maghrebian Southern Tethys to Arabia.

  6. Distillation of oil shales

    Energy Technology Data Exchange (ETDEWEB)

    Bronder, G A

    1926-03-22

    To distill oil shales, cannel coals, and other carbonaceous materials for the extraction therefrom of hydrocarbons and volatile nitrogenous compounds, hard non-condensable gases from the condensers and scrubbers are withdrawn by blowers and admixed with burnt gases, obtained through conduits from the flues of heaters, and forced downwardly through horizontal chambers, connected by vertical conduits, of the heaters and delivered into the retort beneath the grate. Passing upwardly through the charge they vaporize the volatile substances in the shale, and a suction pump removes the vapors from the top of the retort. Immediately they are produced and at substantially the same temperature as that at which they emanate, thus preventing cracking of the oil vapors and condensation of the oil at the top of the retort. The amount of burnt flue gas admixed with the hard gases is regulated by two valves until a required uniform temperature is obtained. A generator supplies producer gas to a heater at the commencement of the retorting operation for circulation through the shale charge to initially produce oil vapors. The generator is connected by a pipe to the gas conduit leading to blowers.

  7. Apparatus for recovering oil from Posidonien shale

    Energy Technology Data Exchange (ETDEWEB)

    1920-04-13

    Equipment for recovering oil from shale and the like, as well as the distilling of coal is characterized in that a number of chambers provided in a known way with upper and lower air supply are arranged open to the receiver of the oil vapors through removable domes which can be attached to the usual oil-vapor carry-off. Arrangement is characterized in that the domes are movable to the side, so that they can be interchangeably attached to the different chambers.

  8. Early to middle Jurassic salt in Baltimore Canyon trough

    Science.gov (United States)

    McKinney, B. Ann; Lee, Myung W.; Agena, Warren F.; Poag, C. Wylie

    2005-01-01

    A pervasive, moderately deep (5-6 s two-way traveltime), high-amplitude reflection is traced on multichannel seismic sections over an approximately 7500 km² area of Baltimore Canyon Trough. The layer associated with the reflection is about 25 km wide, about 60 m thick in the center, and thins monotonically laterally, though asymmetrically, at the edges. Geophysical characteristics are compatible with an interpretation of this negative-polarity reflector as a salt lens deposited on the top of a synrift evaporite sequence. However, alternative interpretations of the layer as gas-saturated sediments, an overpressured shale, or a weathered igneous intrusion are also worthy of consideration.Geophysical analyses were made on three wavelet- and true-amplitude processed multichannel seismic dip lines. The lens-shaped layer demarked by the reflection has a velocity of 4.4 km/s; the lens lies within strata having velocities of 5.3 to 5.7 km/s. A trough marking the onset of the lens has an amplitude that is 10 to 20 db greater than reflections from the encasing layers and an apparent reflection coefficient of -0.24. Using amplitude versus offset analysis methods, we determined that observed reflection coefficients, though variable, decrease consistently with respect to increasing offset. Linear inversion yields a low density, about 2.2 g/cc. Integration of one of the true-amplitude-processed lines and one-dimensional modeling of the layer provide data on the impedance contrast and interference patterns that further reinforce the salt lens interpretation.The thin, horizontal salt lens was probably deposited or precipitated during the Jurassic in a shallow, narrow (peripheral) rift basin, as rifting progressed down the North Atlantic margin. Unlike thicker deposits in other areas that deformed and flowed, often into diapir structures, this thin lens has remained relatively undisturbed since deposition.

  9. Middle to late Jurassic in Poland; Mellem - Oevre jura i Polen

    Energy Technology Data Exchange (ETDEWEB)

    Poulsen, N.E.; Bojesen-Koefoed, J.; Drewniak, A.; Glowniak, E.; Ineson, J.; Matyja, B.A.; Merta, T.; Wierzbowski, A.

    1998-12-01

    Results of this project have contributed to the renewed research in the area of the Middle Jurassic ammonite stratigraphy. Upper Jurassic ammonite stratigraphy is a very actively researched field at the Geological Institute of the Warsaw University. The stratigraphical distribution of dinoflagellate cysts within the Upper Bajocian-Bathonian-Lower Callovian has provided a detailed correlation between the Polish Submediterranean Province (northern Tethyan realm) and the Subboreal Province of the North Sea area (chronostratigraphy and dinoflagellate zonation). One of the most interesting results is the improved correlation of the Oxfordian/Kimmeridgean boundary between these two provinces. The source mineral research contributed new data about the oil/gas potential of megafacies in the central Poland. The planned model development of catagenesis of Middle Jurassic clay sediments in relation to salt deposits could not be established from the found low TOC values and very low hydrogen index values between 6 and 141. The organic material can be characterized as kerogen-type III/IV. Kerogen is considered generally immature with regard to oil/gas formation. The detailed study of sponge bioherms in North-Western Poland has resulted in better understanding of the architecture and evolution of these bioherms. (EG)

  10. The oldest known snakes from the Middle Jurassic-Lower Cretaceous provide insights on snake evolution.

    Science.gov (United States)

    Caldwell, Michael W; Nydam, Randall L; Palci, Alessandro; Apesteguía, Sebastián

    2015-01-27

    The previous oldest known fossil snakes date from ~100 million year old sediments (Upper Cretaceous) and are both morphologically and phylogenetically diverse, indicating that snakes underwent a much earlier origin and adaptive radiation. We report here on snake fossils that extend the record backwards in time by an additional ~70 million years (Middle Jurassic-Lower Cretaceous). These ancient snakes share features with fossil and modern snakes (for example, recurved teeth with labial and lingual carinae, long toothed suborbital ramus of maxillae) and with lizards (for example, pronounced subdental shelf/gutter). The paleobiogeography of these early snakes is diverse and complex, suggesting that snakes had undergone habitat differentiation and geographic radiation by the mid-Jurassic. Phylogenetic analysis of squamates recovers these early snakes in a basal polytomy with other fossil and modern snakes, where Najash rionegrina is sister to this clade. Ingroup analysis finds them in a basal position to all other snakes including Najash.

  11. The Jurassic-Cretaceous basaltic magmatism of the Oued El-Abid syncline (High Atlas, Morocco): Physical volcanology, geochemistry and geodynamic implications

    Science.gov (United States)

    Bensalah, Mohamed Khalil; Youbi, Nasrrddine; Mata, João; Madeira, José; Martins, Línia; El Hachimi, Hind; Bertrand, Hervé; Marzoli, Andrea; Bellieni, Giuliano; Doblas, Miguel; Font, Eric; Medina, Fida; Mahmoudi, Abdelkader; Beraâouz, El Hassane; Miranda, Rui; Verati, Chrystèle; De Min, Angelo; Ben Abbou, Mohamed; Zayane, Rachid

    2013-05-01

    Basaltic lava flows, dykes and sills, interbedded within red clastic continental sedimentary sequences (the so called "Couches Rouges") are widespread in the Oued El-Abid syncline. They represent the best candidates to study the Jurassic-Cretaceous magmatism in the Moroccan High Atlas. The volcanic successions were formed during two pulses of volcanic activity, represented by the Middle to Upper Jurassic basaltic sequence B1 (1-4 eruptions) and the Lower Cretaceous basaltic sequence B2 (three eruptions). Whether belonging to the B1 or B2, the lava flows present morphology and internal structures typical of inflated pahoehoe. Our geochemical data show that, at least for Jurassic magmatism, the dykes, and sills cannot be considered as strictly representing the feeders of the sampled lava flows. The Middle to Upper Jurassic pulse is moderately alkaline in character, while the Lower Cretaceous one is transitional. Crustal contamination plays a minor role in the petrogenesis of these magmas, which were generated by variable partial melting degrees of a garnet-bearing mantle source. Magmatism location was controlled by pre-existing Hercynian fault systems reactivated during a Middle to Upper Jurassic-Cretaceous rifting event. The associated lithospheric stretching induced melting, by adiabatic decompression, of enriched low-solidus infra-lithospheric domains.

  12. Yield and characteristics of shale oil from the retorting of oil shale and fine oil-shale ash mixtures

    International Nuclear Information System (INIS)

    Niu, Mengting; Wang, Sha; Han, Xiangxin; Jiang, Xiumin

    2013-01-01

    Highlights: • The whole formation process of shale oil might be divided into four stages. • Higher ash/shale mass ratio intensified the cracking and coking of shale oil. • Ash/shale ratio of 1:2 was recommended for oil shale fluidized bed retort with fine oil-shale ash as solid heat carrier. - Abstract: For exploring and optimizing the oil shale fluidized bed retort with fine oil-shale ash as a solid heat carrier, retorting experiments of oil shale and fine oil-shale ash mixtures were conducted in a lab-scale retorting reactor to investigate the effects of fine oil-shale ash on shale oil. Oil shale samples were obtained from Dachengzi Mine, China, and mixed with fine oil-shale ash in the ash/shale mass ratios of 0:1, 1:4, 1:2, 1:1, 2:1 and 4:1. The experimental retorting temperature was enhanced from room temperature to 520 °C and the average heating rate was 12 °C min −1 . It was found that, with the increase of the oil-shale ash fraction, the shale oil yield first increased and then decreased obviously, whereas the gas yield appeared conversely. Shale oil was analyzed for the elemental analysis, presenting its atomic H/C ratio of 1.78–1.87. Further, extraction and simulated distillation of shale oil were also conducted to explore the quality of shale oil. As a result, the ash/shale mixing mass ratio of 1:2 was recommended only for the consideration of increasing the yield and quality of shale oil

  13. The influence of hurricanes upon the quiet depositional conditions in the Lower Emsian La Vid shales of Colle (NW Spain)

    NARCIS (Netherlands)

    Stel, Jan H.

    1976-01-01

    The author supposes that the fossil content of thin carbonate units in the Upper La Vid shales (Lower Devonian) of Colle was influenced by heavy storms like hurricanes. Apart from microplankton (Cramer, 1964) no fossils are found in the shales. Together with the very well developed fissility of the

  14. Oil shale (in memoriam)

    International Nuclear Information System (INIS)

    Strandberg, Marek

    2000-01-01

    Plans for the continued use of oil shale may lead the development of this country into an impasse. To this day no plans have been made for transition from the use of energy based on fossil fuels to that based on renewable resources. Without having any clear strategic plan politicians have been comforting both themselves and the population with promises to tackle the problem when the right time comes. Today the only enterprise whose cash flows and capital would really make it possible to reform the power industry is the firm Eesti Energia (Estonian Energy). However, its sole present shareholder - the state - prefers the sale of the firm's shares to carrying out a radical reform. At the same time, local consumers are likely to rather be willing to pay for the expensive electric energy produced from renewable resources than for that produced from fossil fuels, the price of which will also remain high due to the pollution tax. Practically it is impossible to buy a globally balanced environment for money - pollution taxes are but punitive mechanisms. The investments made into the oil-shale industry will also reinforce the cultural distance of North-East Estonia from the rest of Estonia - the uniform and prevalently Russian-speaking industrial area will be preserved as long as capital will continue to flow into the oil shale industry concentrated there. The way out would be for industries to make wider use of ecological and ecosystemic technologies and for the state to enforce ecologically balanced economic and social policies. (author)

  15. Process for refining shale bitumen

    Energy Technology Data Exchange (ETDEWEB)

    Plauson, H

    1920-09-19

    A process is disclosed for refining shale bitumen for use as heavy mineral oil, characterized by mixtures of blown hard shale pitch and heavy mineral oil being blown with hot air at temperatures of 120 to 150/sup 0/ with 1 to 3 percent sulfur, and if necessary with 0.5 to 3 percent of an aldehyde.

  16. Distilling shale and the like

    Energy Technology Data Exchange (ETDEWEB)

    Gee, H T.P.

    1922-02-23

    In distilling shale or like bituminous fuels by internal heating with hot gas obtained by the gasifying of the shale residues with air or steam or a mixture of these, the amount and temperature of the gaseous distilling medium is regulated between the gasifying and the distilling chambers, by the introduction of cold gas or air.

  17. Shale Gas Technology. White Paper

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-09-15

    Shale gas is extracted using horizontal drilling and hydraulic fracturing or 'fracking'. None of which are particularly new technologies or shale gas specific. In this white paper attention is paid to Horizontal drilling; Hydraulic fracturing or 'frackin'; Other 'unconventionals'; and Costs.

  18. Shale Gas Technology. White Paper

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-09-15

    Shale gas is extracted using horizontal drilling and hydraulic fracturing or 'fracking'. None of which are particularly new technologies or shale gas specific. In this white paper attention is paid to Horizontal drilling; Hydraulic fracturing or 'frackin'; Other 'unconventionals'; and Costs.

  19. Recovering valuable shale oils, etc

    Energy Technology Data Exchange (ETDEWEB)

    Engler, C

    1922-09-26

    A process is described for the recovery of valuable shale oils or tars, characterized in that the oil shale is heated to about 300/sup 0/C or a temperature not exceeding this essentially and then is treated with a solvent with utilization of this heat.

  20. Chemical process for improved oil recovery from Bakken shale

    Energy Technology Data Exchange (ETDEWEB)

    Shuler, Patrick; Tang, Hongxin; Lu, Zayne [ChemEOR Inc (United States); Tang, Youngchun [Power Environmental Energy Research Institute (United States)

    2011-07-01

    This paper presents the new chemically-improved oil recovery process (IOR) process for Bakken formation reservoirs. A custom surfactant agent can be used in standard hydraulic fracturing treatments in the Bakken to increase oil recovery. The rock formation consists of three members: the lower shale, middle dolostone and the upper shale. The dolostone was deposited as a coastal carbonate during shallower water and the shales were deposited in a relatively deep marine condition. With the widespread advent of horizontal well drilling and large-volume hydraulic fracturing treatments, production from the Bakken has become very active. The experimental results exhibited that specialized surfactant formulations will interact with this mixed oil-wet low permeability middle member to produce more oil. It was also observed that oil recovery by spontaneous imbibition was fast and significant. The best surfactant found in this study is compatible with a common fracture fluid system.

  1. Organic substances of bituminous shales

    Energy Technology Data Exchange (ETDEWEB)

    Lanin, V A; Pronina, M V

    1944-01-01

    Samples of Gdov (Estonia) and Volga (Russia) oil shales were oxidized by alkaline permanganate to study the distribution of carbon and the composition of the resulting oxidation products. Gdov shale was rather stable to oxidation and, after 42 hours 61.2 percent of the organic material remained unoxidized. Five hundred hours were required for complete oxidation, and the oxidation products consisted of CO/sub 2/, acetic, oxalic, and succinic acids. The oxidation products from Volga shale consisted of CO/sub 2/, acetic, oxalic, succinic, adipic, phthalic, benzenetricarboxylic, benzenetetracarboxylic, and benzenepentacarboxylic acids. The results indicated that Gdov shale is free of humic substances and is of sapropelic origin, while Volga shale is of sapropelic-humic origin.

  2. The Shale Gas potential of Lower Carboniferous Sediments in Germany

    Science.gov (United States)

    Kerschke, D.; Mihailovic, A.; Schulz, H., -M.; Horsfield, B.

    2012-04-01

    Organic-rich Carboniferous sediments are proven source rocks for conventional gas systems in NW Europe and are likely gas shale candidates. Within the framework of GeoEnergie, an initiative to strengthen scientific excellence, funded by the German Ministry of Education and Research (BMBF), the influence of palaeogeography and basin dynamics on sedimentology and diagenesis is being investigated. Our aim is to unravel the evolution of shale gas-relevant properties which control gas prospectivity and production parameters like porosity, brittleness, etc. for the Lower Carboniferous in Germany. Northern Germany is underlain by thick, mudstone-bearing Carboniferous successions with a wide range of thermal maturities. Some of these mudstone horizons are rich in organic carbon which is either of marine and/or terrigenous origin. During the Carboniferous deposition of fine-grained, TOC-rich basinal sediments changed into shallow marine to paralic siliciclastic sediments (carbonates during the Lower Carboniferous) in the north, and grade into coarse-grained sediments close to the uprising Variscan mountains in the south. As a result different architectural elements including TOC-rich fine-grained sediments like basinal shales, fine-grained parts of turbidites, and shallow marine mudstones occur in both the Lower and the Upper Carboniferous section. A high shale gas potential occurs in basinal shales of Namurian age with marine organic material and TOC contents of up to 8 % (Rhenish Alum Shales). Such sediments with thermal maturities between 1.3 to 3.0 % vitrinite reflectance and sufficient quartz contents occur in wide areas of present-day Central European Basins System (CEBS), and are at favourable depth for shale gas exploration predominantly along the southern CEBS margin.

  3. Treatment of oil shale

    Energy Technology Data Exchange (ETDEWEB)

    Brown, H L

    1922-07-04

    To distill oil shale in lump form, it is fed as a continuous charge through an axially rotating externally heated retorting chamber, where the exposed surfaces of the lumps are gradually decomposed by destructive distillation, and light physical shocks are continuously administered to them, due to their tumbling-over motion and their contact with the ribs, to knock off the decomposing surfaces and present fresh surfaces for distillation. The vapors are withdrawn through a conduit, and the partially distilled lumps are fed through a shoot into a plurality of rotating externally heated retorts, similar in character to the first retort, from whence the vapors pass through a conduit to condensing apparatus, from which the permanent gases are withdrawn, and used for fuel in the distillation zone, while the residue is discharged into a water well. An auxiliary heating conduit, having a burner discharging into it, may be employed, while in some cases steam may be used if required. In two modifications, different arrangements of the retorts are shown, as well as means within the retorts for breaking up the lumps of shale.

  4. Distillation of shale

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, J

    1877-01-05

    The retort consists of a trough fitted with a hood, the edges of which hood dip into a channel of water formed round the sides of the trough, and thereby seal the retort. The shale is introduced at one end of the hood through a double-valved inlet hopper, and is moved along the retort by transverse scrapers or paddles. At the other end it falls through a double-valved outlet upon a set of firebars which carry it along under the retort, where either alone or in admixture with other fuel it is used for heating the vessel. The vapors from the shale pass off through pipes in the hood, or an inverted channel may be formed along the center of the hood for collecting the vapors from different parts of the vessel. The scrapers are worked by rocking shafts supported on bearings in the edges of the trough, and are made to feather when moving in a direction from the discharged end. Levers from the rocking shafts project down into the water channel, where they are connected with horizontal bars made to reciprocate longitudinally by suitable means, thus working the scrapers without using stuffing-boxes. Rotating scrapers may be substituted for the reciprocating ones.

  5. Evaluation of excavation experience: Pierre shale. Final report

    International Nuclear Information System (INIS)

    Abel, J.F. Jr.; Gentry, D.W.

    1975-01-01

    Pierre shale and its stratigraphic equivalents represent a potentially favorable geologic environment for underground storage of hazardous waste products. These rock formations cover great areal and vertical extents, and represent some of the least permeable rock formations within the continental United States. There are, however, several engineering problems associated with constructing underground openings in Pierre shale. This formation is relatively weak and tends to deteriorate rather rapidly if not protected from the mine environment. It will be necessary to place all underground openings below the surficially weathered upper 50 to 70 feet of Pierre shale which contains groundwater moving on fracture permeability. The optimum site for disposal of hazardous waste in Pierre shale, or its stratigraphic equivalents, would be a seismically stable platform bounded on all sides by faults. The optimum size of individual openings would be the minimum necessary for access, storage, and retrieval of waste components. Underground excavations in Pierre shale must be made with care, must be of limited dimensions, must be widely spaced, must be protected from prolonged contact with the mine environment, must be supported immediately after excavation, and must be sited to avoid areas of faulting and(or) intense jointing. Underground openings constructed with boring machines and supported with wet shotcrete are recommended

  6. Sandstone-body and shale-body dimensions in a braided fluvial system: Salt wash sandstone member (Morrison formation), Garfield County, Utah

    Science.gov (United States)

    Robinson, J.W.; McCabea, P.J.

    1997-01-01

    Excellent three-dimensional exposures of the Upper Jurassic Salt Wash Sandstone Member of the Morrison Formation in the Henry Mountains area of southern Utah allow measurement of the thickness and width of fluvial sandstone and shale bodies from extensive photomosaics. The Salt Wash Sandstone Member is composed of fluvial channel fill, abandoned channel fill, and overbank/flood-plain strata that were deposited on a broad alluvial plain of low-sinuosity, sandy, braided streams flowing northeast. A hierarchy of sandstone and shale bodies in the Salt Wash Sandstone Member includes, in ascending order, trough cross-bedding, fining-upward units/mudstone intraclast conglomerates, singlestory sandstone bodies/basal conglomerate, abandoned channel fill, multistory sandstone bodies, and overbank/flood-plain heterolithic strata. Trough cross-beds have an average width:thickness ratio (W:T) of 8.5:1 in the lower interval of the Salt Wash Sandstone Member and 10.4:1 in the upper interval. Fining-upward units are 0.5-3.0 m thick and 3-11 m wide. Single-story sandstone bodies in the upper interval are wider and thicker than their counterparts in the lower interval, based on average W:T, linear regression analysis, and cumulative relative frequency graphs. Multistory sandstone bodies are composed of two to eight stories, range up to 30 m thick and over 1500 m wide (W:T > 50:1), and are also larger in the upper interval. Heterolithic units between sandstone bodies include abandoned channel fill (W:T = 33:1) and overbank/flood-plain deposits (W:T = 70:1). Understanding W:T ratios from the component parts of an ancient, sandy, braided stream deposit can be applied in several ways to similar strata in other basins; for example, to (1) determine the width of a unit when only the thickness is known, (2) create correlation guidelines and maximum correlation lengths, (3) aid in interpreting the controls on fluvial architecture, and (4) place additional constraints on input variables to

  7. Sedimentary record of subsidence pulse at the Triassic/Jurassic boundary interval in the Slovenian Basin (eastern Southern Alps

    Directory of Open Access Journals (Sweden)

    Rožič Boštjan

    2017-08-01

    Full Text Available In the Alpine Realm the Early Jurassic is characterized by the disintegration and partial drowning of vast platform areas. In the eastern part of the Southern Alps (present-day NW Slovenia, the Julian Carbonate Platform and the adjacent, E-W extending Slovenian Basin underwent partial disintegration, drowning and deepening from the Pliensbachian on, whereas only nominal environmental changes developed on the large Dinaric (Friuli, Adriatic Carbonate Platform to the south (structurally part of the Dinarides. These events, however, were preceded by an earlier - and as yet undocumented extensional event - that took place near the Triassic/Jurassic boundary. This paper provides evidence of an accelerated subsidence from four selected areas within the Slovenian Basin, which show a trend of eastwardly-decreasing deformation. In the westernmost (Mrzli vrh section - the Upper Triassic platform-margin - massive dolomite is overlain by the earliest Jurassic toe-of-slope carbonate resediments and further, by basin-plain micritic limestone. Further east (Perbla and Liščak sections the Triassic-Jurassic transition interval is marked by an increase in resedimented carbonates. We relate this to the increasing inclination and segmentation of the slope and adjacent basin floor. The easternmost (Mt. Porezen area shows a rather monotonous, latest Triassic-Early Jurassic basinal sedimentation. However, changes in the thickness of the Hettangian-Pliensbachian Krikov Formation point to a tilting of tectonic blocks within the basin area. Lateral facies changes at the base of the formation indicate that the tilting occurred at and/or shortly after the Triassic/Jurassic boundary

  8. Sedimentary record of subsidence pulse at the Triassic/Jurassic boundary interval in the Slovenian Basin (eastern Southern Alps)

    Science.gov (United States)

    Rožič, Boštjan; Jurkovšek, Tea Kolar; Rožič, Petra Žvab; Gale, Luka

    2017-08-01

    In the Alpine Realm the Early Jurassic is characterized by the disintegration and partial drowning of vast platform areas. In the eastern part of the Southern Alps (present-day NW Slovenia), the Julian Carbonate Platform and the adjacent, E-W extending Slovenian Basin underwent partial disintegration, drowning and deepening from the Pliensbachian on, whereas only nominal environmental changes developed on the large Dinaric (Friuli, Adriatic) Carbonate Platform to the south (structurally part of the Dinarides). These events, however, were preceded by an earlier - and as yet undocumented extensional event - that took place near the Triassic/Jurassic boundary. This paper provides evidence of an accelerated subsidence from four selected areas within the Slovenian Basin, which show a trend of eastwardly-decreasing deformation. In the westernmost (Mrzli vrh) section - the Upper Triassic platform-margin - massive dolomite is overlain by the earliest Jurassic toe-of-slope carbonate resediments and further, by basin-plain micritic limestone. Further east (Perbla and Liščak sections) the Triassic-Jurassic transition interval is marked by an increase in resedimented carbonates. We relate this to the increasing inclination and segmentation of the slope and adjacent basin floor. The easternmost (Mt. Porezen) area shows a rather monotonous, latest Triassic-Early Jurassic basinal sedimentation. However, changes in the thickness of the Hettangian-Pliensbachian Krikov Formation point to a tilting of tectonic blocks within the basin area. Lateral facies changes at the base of the formation indicate that the tilting occurred at and/or shortly after the Triassic/Jurassic boundary

  9. A marine biogeochemical perspective on black shale deposition

    Science.gov (United States)

    Piper, D. Z.; Calvert, S. E.

    2009-06-01

    Deposition of marine black shales has commonly been interpreted as having involved a high level of marine phytoplankton production that promoted high settling rates of organic matter through the water column and high burial fluxes on the seafloor or anoxic (sulfidic) water-column conditions that led to high levels of preservation of deposited organic matter, or a combination of the two processes. Here we review the hydrography and the budgets of trace metals and phytoplankton nutrients in two modern marine basins that have permanently anoxic bottom waters. This information is then used to hindcast the hydrography and biogeochemical conditions of deposition of a black shale of Late Jurassic age (the Kimmeridge Clay Formation, Yorkshire, England) from its trace metal and organic carbon content. Comparison of the modern and Jurassic sediment compositions reveals that the rate of photic zone primary productivity in the Kimmeridge Sea, based on the accumulation rate of the marine fraction of Ni, was as high as 840 g organic carbon m - 2 yr -1. This high level was possibly tied to the maximum rise of sea level during the Late Jurassic that flooded this and other continents sufficiently to allow major open-ocean boundary currents to penetrate into epeiric seas. Sites of intense upwelling of nutrient-enriched seawater would have been transferred from the continental margins, their present location, onto the continents. This global flooding event was likely responsible for deposition of organic matter-enriched sediments in other marine basins of this age, several of which today host major petroleum source rocks. Bottom-water redox conditions in the Kimmeridge Sea, deduced from the V:Mo ratio in the marine fraction of the Kimmeridge Clay Formation, varied from oxic to anoxic, but were predominantly suboxic, or denitrifying. A high settling flux of organic matter, a result of the high primary productivity, supported a high rate of bacterial respiration that led to the

  10. The pore structure and fractal characteristics of shales with low thermal maturity from the Yuqia Coalfield, northern Qaidam Basin, northwestern China

    Science.gov (United States)

    Hou, Haihai; Shao, Longyi; Li, Yonghong; Li, Zhen; Zhang, Wenlong; Wen, Huaijun

    2018-03-01

    The continental shales from the Middle Jurassic Shimengou Formation of the northern Qaidam Basin, northwestern China, have been investigated in recent years because of their shale gas potential. In this study, a total of twenty-two shale samples were collected from the YQ-1 borehole in the Yuqia Coalfield, northern Qaidam Basin. The total organic carbon (TOC) contents, pore structure parameters, and fractal characteristics of the samples were investigated using TOC analysis, low-temperature nitrogen adsorption experiments, and fractal analysis. The results show that the average pore size of the Shimengou shales varied from 8.149 nm to 20.635 nm with a mean value of 10.74 nm, which is considered mesopore-sized. The pores of the shales are mainly inkbottle- and slit-shaped. The sedimentary environment plays an essential role in controlling the TOC contents of the low maturity shales, with the TOC values of shales from deep to semi-deep lake facies (mean: 5.23%) being notably higher than those of the shore-shallow lake facies (mean: 0.65%). The fractal dimensions range from 2.4639 to 2.6857 with a mean of 2.6122, higher than those of marine shales, which indicates that the pore surface was rougher and the pore structure more complex in these continental shales. The fractal dimensions increase with increasing total pore volume and total specific surface area, and with decreasing average pore size. With increasing TOC contents in shales, the fractal dimensions increase first and then decrease, with the highest value occurring at 2% of TOC content, which is in accordance with the trends between the TOC and both total specific surface area and total pore volume. The pore structure complexity and pore surface roughness of these low-maturity shales would be controlled by the combined effects of both sedimentary environments and the TOC contents.

  11. Jurassic-Paleogene intraoceanic magmatic evolution of the Ankara Mélange, north-central Anatolia, Turkey

    Science.gov (United States)

    Sarifakioglu, E.; Dilek, Y.; Sevin, M.

    2014-02-01

    Oceanic rocks in the Ankara Mélange along the Izmir-Ankara-Erzincan suture zone (IAESZ) in north-central Anatolia include locally coherent ophiolite complexes (∼ 179 Ma and ∼ 80 Ma), seamount or oceanic plateau volcanic units with pelagic and reefal limestones (96.6 ± 1.8 Ma), metamorphic rocks with ages of 256.9 ± 8.0 Ma, 187.4 ± 3.7 Ma, 158.4 ± 4.2 Ma, and 83.5 ± 1.2 Ma indicating northern Tethys during the late Paleozoic through Cretaceous, and subalkaline to alkaline volcanic and plutonic rocks of an island arc origin (∼ 67-63 Ma). All but the arc rocks occur in a shale-graywacke and/or serpentinite matrix, and are deformed by south-vergent thrust faults and folds that developed in the middle to late Eocene due to continental collisions in the region. Ophiolitic volcanic rocks have mid-ocean ridge (MORB) and island arc tholeiite (IAT) affinities showing moderate to significant large ion lithophile elements (LILE) enrichment and depletion in Nb, Hf, Ti, Y and Yb, which indicate the influence of subduction-derived fluids in their melt evolution. Seamount/oceanic plateau basalts show ocean island basalt (OIB) affinities. The arc-related volcanic rocks, lamprophyric dikes and syenodioritic plutons exhibit high-K shoshonitic to medium- to high-K calc-alkaline compositions with strong enrichment in LILE, rare earth elements (REE) and Pb, and initial ɛNd values between +1.3 and +1.7. Subalkaline arc volcanic units occur in the northern part of the mélange, whereas the younger alkaline volcanic rocks and intrusions (lamprophyre dikes and syenodioritic plutons) in the southern part. The late Permian, Early to Late Jurassic, and Late Cretaceous amphibole-epidote schist, epidote-actinolite, epidote-chlorite and epidote-glaucophane schists represent the metamorphic units formed in a subduction channel in the northern Neotethys. The Middle to Upper Triassic neritic limestones spatially associated with the seamount volcanic rocks indicate that the northern

  12. New evidence for mammaliaform ear evolution and feeding adaptation in a Jurassic ecosystem

    Science.gov (United States)

    Luo, Zhe-Xi; Meng, Qing-Jin; Grossnickle, David M.; Liu, Di; Neander, April I.; Zhang, Yu-Guang; Ji, Qiang

    2017-08-01

    Stem mammaliaforms are forerunners to modern mammals, and they achieved considerable ecomorphological diversity in their own right. Recent discoveries suggest that eleutherodontids, a subclade of Haramiyida, were more species-rich during the Jurassic period in Asia than previously recognized. Here we report a new Jurassic eleutherodontid mammaliaform with an unusual mosaic of highly specialized characteristics, and the results of phylogenetic analyses that support the hypothesis that haramiyidans are stem mammaliaforms. The new fossil shows fossilized skin membranes that are interpreted to be for gliding and a mandibular middle ear with a unique character combination previously unknown in mammaliaforms. Incisor replacement is prolonged until well after molars are fully erupted, a timing pattern unique to most other mammaliaforms. In situ molar occlusion and a functional analysis reveal a new mode of dental occlusion: dual mortar-pestle occlusion of opposing upper and lower molars, probably for dual crushing and grinding. This suggests that eleutherodontids are herbivorous, and probably specialized for granivory or feeding on soft plant tissues. The inferred dietary adaptation of eleutherodontid gliders represents a remarkable evolutionary convergence with herbivorous gliders in Theria. These Jurassic fossils represent volant, herbivorous stem mammaliaforms associated with pre-angiosperm plants that appear long before the later, iterative associations between angiosperm plants and volant herbivores in various therian clades.

  13. Exotic Members of Southern Alaska's Jurassic Arc

    Science.gov (United States)

    Todd, E.; Jones, J. V., III; Karl, S. M.; Box, S.; Haeussler, P. J.

    2017-12-01

    The Jurassic Talkeetna arc and contemporaneous plutonic rocks of the Alaska-Aleutian Range batholith (ARB) are key components of the Peninsular terrane of southern Alaska. The Talkeetna arc, considered to be a type example of an intra-oceanic arc, was progressively accreted to northwestern North America in the Jurassic to Late Cretaceous, together with associated components of the Wrangellia Composite terrane. Older Paleozoic and Mesozoic rock successions closely associated with the ARB suggest that at least part of the Peninsular terrane might be an overlap succession built on pre-existing crust, possibly correlative with the Wrangellia terrane to the east. However, the relationship between the Talkeetna arc, ARB, and any pre-existing crust remains incompletely understood. Field investigations focused on the petrogenesis of the ARB near Lake Clark National Park show that Jurassic to Late Cretaceous plutonic rocks commonly host a diverse range of mineralogically distinct xenolith inclusions, ranging in size from several cm to hundreds of meters. The modal fraction of these inclusions ranges from 50% in some outcrops. They are generally mafic in composition and, with few exceptions, are more mafic than host plutonic rocks, although they are observed as both igneous (e.g., gabbro cumulate, diorite porphyry) and metamorphic types (e.g., amphibolite, gneiss and quartzite). Inclusion shapes range from angular to rounded with sharp to diffuse boundaries and, in some instances, are found as planar, compositionally distinct bands or screens containing high-temperature ductile shear fabrics. Other planar bands are more segmented, consistent with lower-temperature brittle behavior. Comparison of age, geochemical fractionation trends, and isotope systematics between the inclusions and host plutons provides a critical test of whether they are co-genetic with host plutons. Where they are related, mafic inclusions provide clues about magmatic evolution and fractionation history

  14. Carbon sequestration in depleted oil shale deposits

    Science.gov (United States)

    Burnham, Alan K; Carroll, Susan A

    2014-12-02

    A method and apparatus are described for sequestering carbon dioxide underground by mineralizing the carbon dioxide with coinjected fluids and minerals remaining from the extraction shale oil. In one embodiment, the oil shale of an illite-rich oil shale is heated to pyrolyze the shale underground, and carbon dioxide is provided to the remaining depleted oil shale while at an elevated temperature. Conditions are sufficient to mineralize the carbon dioxide.

  15. Distilling oil shale

    Energy Technology Data Exchange (ETDEWEB)

    Crozier, R H

    1923-04-18

    In the fractional distillation of oils from oil shale and similar materials the charge is passed continuously through a vertical retort heated externally by hot combustion gases in flues and internally by the passage of these gases through flues passing through the retort so that zones of increasing temperature are maintained. A vapor trap is provided in each zone having an exit pipe leading through a dust trap to a condenser. The bottoms of the conical vapor traps are provided with annular passages perforated to permit of steam being sprayed into the charge to form screens which prevent the vapors in different zones from mingling, and steam may also be introduced through perforations in an annular steam box. Dampers are provided to control the passage of the heating gases through the flues independently.

  16. Distilling shale and coal

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, H; Young, G

    1923-01-09

    In a process of recovering oil from shale or coal the material is ground and may be subjected to a cleaning or concentrating process of the kind described in Specification 153,663 after which it is distilled in a furnace as described in Specification 13,625/09 the sections of the furnace forming different temperature zones, and the rate of the passage of the material is regulated so that distillation is complete with respect to the temperature of each zone, the whole distillation being accomplished in successive stages. The vapors are taken off at each zone and superheated steam may be passed into the furnace at suitable points and the distillation terminated at any stage of the process.

  17. Distillation of shale

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, E L

    1923-09-04

    To retort shale, lignite, coal, or the like for the recovery of gas and oils or spirits, it is fed through a hopper and then passed in a thin film through the space between the casing and outer shell by means of louvres which with the shell and the outer shell are reciprocated vertically. The top of the shell connected by brackets and lifting joists are pivoted to an eccentric driven by a shaft. The spent material passes through openings in the fixed base casting and openings in a moving ring which is rotated by a pawl and ratchet gear actuated by the reciprocation of the shell. The openings are opposite one another at the commencement of the downward movement of the louvres and shell and closed when the louvres are right down and on their upward movement.

  18. Distilling coal, shale, etc

    Energy Technology Data Exchange (ETDEWEB)

    Bussey, C C

    1916-07-17

    In the extraction of vovolatile ingredients from coal, shale, lignite, and other hydrocarbonaceous materials by passing through the material a heating-agent produced by burning at the base of the charge a portion of the material from which the volatile ingredients have been extracted, the temperature of the heating agent is maintained constant by continuously removing the residue from the bottom of the apparatus. The temperature employed is 800/sup 0/F or slightly less, so as to avoid any breaking-down action. As shown the retort is flared downwardly, and is provided at the base with a fireplace, which is in communication with the interior of the retort through flues fitted with screens and dampers. Beneath the bottom of the retort is mounted a movable grate carried on endless sprocket chains, which are preferably set so that the grate inclines downwardly towards the coke, etc.

  19. Recovering oil from shale

    Energy Technology Data Exchange (ETDEWEB)

    Leahey, T; Wilson, H

    1920-11-13

    To recover oil free from inorganic impurities and water, and utilize the oil vapor and tarry matter for the production of heat, shale is heated in a retort at a temperature of not less than 120/sup 0/C. The vapors pass by a pipe into a water jacketed condenser from which the condensate and gas pass through a pipe into a chamber and then by a pipe to a setting chamber from where the light oils are decanted through a pipe into a tank. The heavy oil is siphoned through a pipe into a tank, while the gas passes through a pipe into a scrubber and then into a drier, exhauster and pipe to the flue and ports, above the fire-bars, into the retort. Air is introduced through a pipe, flue, and ports.

  20. Neutron activation determination of rhenium in shales shales and molybdenites

    International Nuclear Information System (INIS)

    Zajtsev, E.I.; Radinovich, B.S.

    1977-01-01

    Described is the technique for neutron activation determination of rhenium in shales and molybdenites with its radiochemical extraction separation by methyl-ethyl ketone. The sensitivity of the analysis is 5x10 -7 %. Experimental checking of the developed technique in reference to the analysis of shales and molybdenites was carried out. Estimated is the possibility of application of X-ray gamma-spectrometer to instrumental determination of rhenium in molybdenites

  1. Preservation of carbohydrates through sulfurization in a Jurassic euxinic shelf sea: Examination of the Blackstone Band TOC-cycle in the Kimmeridge Clay Formation, UK

    NARCIS (Netherlands)

    Dongen, B.E. van; Schouten, S.; Sinninghe Damsté, J.S.

    2006-01-01

    A complete total organic carbon (TOC) cycle in the Upper Jurassic Kimmeridge Clay Formation (KCF) comprising the extremely TOC-rich (34%) Blackstone Band was studied to investigate the controlling factors on TOC accumulation. Compared with the under- and overlying strata, TOC in the Blackstone

  2. The Middle Jurassic microflora from El Maghara N° 4 borehole, Northern Sinai, Egypt

    Science.gov (United States)

    Mohsen, Sayed Abdel

    The coal bearing formation in El Maghara area, northern Sinai, yielded abundant, diverse and generally well preserved spores, pollen and marine microflora. The palynological analysis of the fine clastic sediments in this formation yielded (71) species related to (44) genera. Three different palynological assemblage zones can be distinguished. The sediments which contain lower and the upper assemblage zones bearing the coal seems, were deposited in non-marine (swamp) environment. In the middle assemblage zone few marine microflora can be identified, indicating a coastal near shore marine environment. Compared with other palynologic data obtained from Egypt and other countries, the three described assemblage zones belong to Middle Jurassic (Bathonian) age.

  3. Discovery of the first ichthyosaur from the Jurassic of India: Implications for Gondwanan palaeobiogeography.

    Directory of Open Access Journals (Sweden)

    Guntupalli V R Prasad

    Full Text Available An articulated and partially preserved skeleton of an ichthyosaur was found in the Upper Jurassic (Upper Kimmeridgian Katrol Formation exposed at a site south of the village Lodai in Kachchh district, Gujarat (western India. Here we present a detailed description and inferred taxonomic relationship of the specimen. The present study revealed that the articulated skeleton belongs to the family Ophthalmosauridae. The new discovery from India further improves the depauperate fossil record of ichthyosaurs from the former Gondwanan continents. Based on the preserved length of the axial skeleton and anterior part of the snout and taking into account the missing parts of the skull and postflexural region, it is suggested that the specimen may represent an adult possibly reaching a length of 5.0-5.5 m. The widespread occurrence of ophthalmosaurids in the Upper Jurassic deposits of western Tethys, Madagascar, South America and India points to possible faunal exchanges between the western Tethys and Gondwanan continents through a southern seaway.

  4. Oil shale utilization in Israel

    International Nuclear Information System (INIS)

    Kaiser, A.

    1993-01-01

    Geological surveys have confirmed the existence of substantial Israeli oil shale reserves. The proven reserves contain approximately 12 billion tons of available ores, and the potential is deemed to be much higher. Economic studies conducted by PAMA indicate promising potential for power generation via Israel oil shale combustion. Electric power from oil shale appears competitive with power generated from coal fired power plants located along the coast. PAMA's demonstration power plant has been in operation since the end of 1989. Based on the successful results of the first year of operation, PAMA and IEC are now engaged in the pre-project program for a 1000 MW commercial oil shale fired power plant, based on eight 120 MW units; the first unit is scheduled to begin operation in 1996

  5. Shale gas: the water myth

    Energy Technology Data Exchange (ETDEWEB)

    O' Shea, Kerry [Dillon Consulting Limited (Canada)

    2010-07-01

    In recent years, due to the depletion of traditional fossil fuel resources and the rising price of energy, production from unconventional gas activities has increased. Large shale gas plays are available in Quebec but environmental concerns, mainly in terms of water resources, have been raised. The aim of this paper is to provide information on the impact of shale gas exploitation on water resources. It is shown herein that shale gas water use is not significant, the water use of 250 wells represents only 0.3% of the Quebec pulp and paper industry's water use, or 0.0004% of the flow of the St Lawrence. It is also shown that the environmental risk associated with fracking and drilling activities is low. This paper demonstrated that as long as industry practices conform to a well-designed regulatory framework, shale gas development in Quebec will have a low impact on water resources and the environment.

  6. BLM Colorado Oil Shale Leases

    Data.gov (United States)

    Department of the Interior — KMZ file Format –This data set contains the Oil Shale Leases for the State of Colorado, derived from Legal Land Descriptions (LLD) contained in the US Bureau of Land...

  7. THE TRIASSIC/JURASSIC BOUNDARY IN THE ANDES OF ARGENTINA

    Directory of Open Access Journals (Sweden)

    ALBERTO C. RICCARDI

    2004-03-01

    Full Text Available The Arroyo Malo Formation at Alumbre Creek, on the northern bank of the Atuel River, west central Argentina, comprises a c. 300 m thick continuous marine succession across the Triassic-Jurassic System boundary, consisting of massive and laminated pelites indicative of a slope depositional environment. Late Triassic invertebrates, including ammonoids, nautiloids, bivalves, gastropods, brachiopods and corals are restricted to the lower 150 m. Beds between 125-135 m from the bottom yield Choristoceras cf. marshi Hauer, a species found in the Marshi/Crickmayi Zone of Europe and North America, together with loose fragments of Psiloceras cf. pressum Hillebrandt, coeval with the lower to middle part of the Hettangian Planorbis Zone. About 80 m higher are beds yielding Psiloceras cf. rectocostatum Hillebrandt, a species that gives name to an Andean biozone partially coeval with the Johnstoni and Plicatulum Subzones, upper Planorbis Zone. Other fossils recorded in the Rhaetian strata of this section are foraminifers, ostracods and plant remains identified as Zuberia cf. zuberi (Szaj. Freng. and Clathropteris sp. The section was also sampled for conodonts and radiolarians, thus far with negative results. A palaeomagnetic study is underway.

  8. Stabilization of gasoline from shale

    Energy Technology Data Exchange (ETDEWEB)

    Benedetti, L

    1929-03-14

    A process is described of stabilizing gasoline from shale, consisting in treating by agitating the gasoline freshly distilled from shale oil with 1.5 percent of its weight of sulfuric acid diluted to more than 10 times its volume, after which separating the pyridine, then treating by agitating with sulfuric acid which treatment separates the unsaturated hydrocarbons and finally treating by agitating with 1.5 percent of its weight of saturated caustic soda solution and washing with water.

  9. Laboratory characterization of shale pores

    Science.gov (United States)

    Nur Listiyowati, Lina

    2018-02-01

    To estimate the potential of shale gas reservoir, one needs to understand the characteristics of pore structures. Characterization of shale gas reservoir microstructure is still a challenge due to ultra-fine grained micro-fabric and micro level heterogeneity of these sedimentary rocks. The sample used in the analysis is a small portion of any reservoir. Thus, each measurement technique has a different result. It raises the question which methods are suitable for characterizing pore shale. The goal of this paper is to summarize some of the microstructure analysis tools of shale rock to get near-real results. The two analyzing pore structure methods are indirect measurement (MIP, He, NMR, LTNA) and direct observation (SEM, TEM, Xray CT). Shale rocks have a high heterogeneity; thus, it needs multiscale quantification techniques to understand their pore structures. To describe the complex pore system of shale, several measurement techniques are needed to characterize the surface area and pore size distribution (LTNA, MIP), shapes, size and distribution of pore (FIB-SEM, TEM, Xray CT), and total porosity (He pycnometer, NMR). The choice of techniques and methods should take into account the purpose of the analysis and also the time and budget.

  10. Geochemical characterization of the Jurassic Amran deposits from Sharab area (SW Yemen): Origin of organic matter, paleoenvironmental and paleoclimate conditions during deposition

    Science.gov (United States)

    Hakimi, Mohammed Hail; Abdullah, Wan Hasiah; Makeen, Yousif M.; Saeed, Shadi A.; Al-Hakame, Hitham; Al-Moliki, Tareq; Al-Sharabi, Kholah Qaid; Hatem, Baleid Ali

    2017-05-01

    Calcareous shales and black limestones of the Jurassic Amran Group, located in the Sharab area (SW Yemen), were analysed based on organic and inorganic geochemical methods. The results of this study were used to reconstruct the paleoenvironmental and paleoclimatic conditions during Jurassic time and their relevance to organic matter enrichment during deposition of the Amran calcareous shale and black limestone deposits. The analysed Amran samples have present-day TOC and Stotal content values in the range of 0.25-0.91 wt % and 0.59-4.96 wt %, respectively. The relationship between Stotal and TOC contents indicates that the Jurassic Amran deposits were deposited in a marine environment as supported by biomarker environmental indicators. Biomarker distributions also reflect that the analysed Amran deposits received high contributions of marine organic matter (e.g., algal and microbial) with minor amount of land plant source inputs. Low oxygen (reducing) conditions during deposition of the Jurassic Amran deposits are indicated from low Pr/Ph values and relatively high elemental ratios of V/Ni and V/(V + Ni). Enrichment in the pyrite grains and very high DOPT and high Fe/Al ratios further suggest reducing bottom waters. This paleo-redox (i.e., reducing) conditions contributed to preservation of organic matter during deposition of the Jurassic Amran deposits. Semi-arid to warm climatic conditions are also evidenced during deposition of the Amran sediments and consequently increased biological productivity within the photic zone of the water column during deposition. Therefore, the increased bio-productivity in combination with good preservation of organic matter identified as the major mechanisms that gave rise to organic matter enrichment. This contradicts with the low organic matter content of the present-day TOC values of less than 1%. The biomarker maturity data indicate that the analysed Amran samples are of high thermal maturity; therefore, the low present-day TOC

  11. Biogenic gas in the Cambrian-Ordovcian Alum Shale (Denmark and Sweden)

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, H.M.; Wirth, R.; Biermann, S.; Arning, E.T. [Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum GFZ, Potsdam (Germany); Krueger, M.; Straaten, N. [BGR Hannover (Germany); Bechtel, A. [Montanuniv. Leoben (Austria); Berk, W. van [Technical Univ. of Clausthal (Germany); Schovsbo, N.H. [Geological Survey of Denmark and Greenland - GEUS, Copenhagen (Denmark); Crabtree, Stephen [Gripen Gas (Sweden)

    2013-08-01

    Shale gas is mainly produced from thermally mature black shales. However, biogenic methane also represents a resource which is often underestimated. Today biogenic methane is being produced from the Upper Devonian Antrim Shale in the Michigan Basin which was the most successfully exploited shale gas system during the 1990-2000 decade in the U.S.A. before significant gas production from the Barnett Shale started (Curtis et al., 2008). The Cambro-Ordovician Alum Shale in northern Europe has thermal maturities ranging from overmature in southern areas (Denmark and southern Sweden) to immature conditions (central Sweden). Biogenic methane is recorded during drilling in central Sweden. The immature Alum Shale in central Sweden has total organic carbon (TOC) contents up to 20 wt%. The hydrogen index HI ranges from 380 to 560 mgHC/gTOC at very low oxygen index (OI) values of around 4 mg CO{sub 2}/gTOC, Tmax ranges between 420 - 430 C. The organic matter is highly porous. In general, the Alum Shale is a dense shale with intercalated sandy beds which may be dense due to carbonate cementation. Secondary porosity is created in some sandy beds due to feldspar dissolution and these beds serve as gas conduits. Methane production rates with shale as substrate in the laboratory are dependent on the kind of hydrocarbon-degrading microbial enrichment cultures used in the incubation experiments, ranging from 10-620 nmol/(g*d). In these experiments, the CO{sub 2} production rate was always higher than for methane. Like the northern part of North America, also Northern European has been covered by glaciers during the Pleistocene and similar geological processes may have developed leading to biogenic shale gas formation. For the Antrim Shale one hypothesis suggests that fresh waters, recharged from Pleistocene glaciation and modern precipitation, suppressed basinal brine salinity along the northern margins of the Michigan Basin to greater depths and thereby enhancing methanogenesis

  12. Mid-ocean ridges produced thicker crust in the Jurassic than in Recent times

    Science.gov (United States)

    Van Avendonk, H. J.; Harding, J.; Davis, J. K.; Lawver, L. A.

    2016-12-01

    We present a compilation of published marine seismic refraction data to show that oceanic crust was 1.7 km thicker on average in the mid-Jurassic (170 Ma) than along the present-day mid-ocean ridge system. Plate reconstructions in a fixed hotspot framework show that the thickness of oceanic crust does not correlate with proximity to mantle hotspots, so it is likely that mid-plate volcanism is not the cause of this global trend. We propose that more melt was extracted from the upper mantle beneath mid-ocean ridges in the Jurassic than in recent times. Numerical studies show that temperature increase of 1 degree C in the mantle can lead to approximately 50-70 m thicker crust, so the upper mantle may have cooled 15-20 degrees C/100 Myr since 170 Ma. This average temperature decrease is larger than the secular cooling rate of the Earth's mantle, which is roughly 10 degrees C/100 Myr since the Archean. Apparently, the present-day configuration and dynamics of continental and oceanic plates removes heat more efficiently from the Earth's mantle than in its earlier history. The increase of ocean crustal thickness with plate age is also stronger in the Indian and Atlantic oceans than in the Pacific Ocean basin. This confirms that thermal insulation by the supercontinent Pangaea raised the temperature of the underlying asthenospheric mantle, which in turn led to more magmatic output at the Jurassic mid-ocean ridges of the Indian and Atlantic oceans.

  13. GRI's Devonian Shales Research Program

    International Nuclear Information System (INIS)

    Guidry, F.K.

    1991-01-01

    This paper presents a summary of the key observations and conclusions from the Gas Research Institute's (GRI's) Comprehensive Study Well (CSW) research program conducted in the Devonian Shales of the Appalachian Basin. Initiated in 1987, the CSW program was a series of highly instrumented study wells drilled in cooperation with industry partners. Seven wells were drilled as part of the program. Extensive data sets were collected and special experiments were run on the CSW's in addition to the operator's normal operations, with the objectives of identifying geologic production controls, refining formation evaluation tools, and improving reservoir description and stimulation practices in the Devonian Shales. This paper highlights the key results from the research conducted in the CSW program in the areas of geologic production controls, formation evaluation, stimulation and reservoir engineering, and field operations. The development of geologic, log analysis, and reservoir models for the Shales from the data gathered and analysis, and reservoir models for the Shales from the data gathered and analyzed during the research is discussed. In addition, on the basis of what was learned in the CSW program, GRI's plans for new research in the Devonian Shales are described

  14. Distillation of shale in situ

    Energy Technology Data Exchange (ETDEWEB)

    de Ganahl, C F

    1922-07-04

    To distill buried shale or other carbon containing compounds in situ, a portion of the shale bed is rendered permeable to gases, and the temperature is raised to the point of distillation. An area in a shale bed is shattered by explosives, so that it is in a relatively finely divided form, and the tunnel is then blocked by a wall, and fuel and air are admitted through pipes until the temperature of the shale is raised to such a point that a portion of the released hydrocarbons will burn. When distillation of the shattered area takes place and the lighter products pass upwardly through uptakes to condensers and scrubbers, liquid oil passes to a tank and gas to a gasometer while heavy unvaporized products in the distillation zone collect in a drain, flow into a sump, and are drawn off through a pipe to a storage tank. In two modifications, methods of working are set out in cases where the shale lies beneath a substantially level surface.

  15. Sedimentation of Jurassic fan-delta wedges in the Xiahuayuan basin reflecting thrust-fault movements of the western Yanshan fold-and-thrust belt, China

    Science.gov (United States)

    Lin, Chengfa; Liu, Shaofeng; Zhuang, Qitian; Steel, Ronald J.

    2018-06-01

    Mesozoic thrusting within the Yanshan fold-and-thrust belt of North China resulted in a series of fault-bounded intramontane basins whose infill and evolution remain poorly understood. In particular, the bounding faults and adjacent sediment accumulations along the western segments of the belt are almost unstudied. A sedimentological and provenance analysis of the Lower Jurassic Xiahuayuan Formation and the Upper Jurassic Jiulongshan Formation have been mapped to show two distinctive clastic wedges: an early Jurassic wedge representing a mass-flow-dominated, Gilbert-type fan delta with a classic tripartite architecture, and an late Jurassic shoal-water fan delta without steeply inclined strata. The basinward migration of the fan-delta wedges, together with the analysis of their conglomerate clast compositions, paleocurrent data and detrital zircon U-Pb age spectra, strongly suggest that the northern-bounding Xuanhuan thrust fault controlled their growth during accumulation of the Jiulongshan Formation. Previous studies have suggested that the fan-delta wedge of the Xiahuayuan Formation was also syntectonic, related to movement on the Xuanhua thrust fault. Two stages of thrusting therefore exerted an influence on the formation and evolution of the Xiahuayuan basin during the early-late Jurassic.

  16. Intelligent fracture creation for shale gas development

    KAUST Repository

    Douglas, Craig C.; Qin, Guan; Collier, Nathan; Gong, Bin

    2011-01-01

    Shale gas represents a major fraction of the proven reserves of natural gas in the United States and a collection of other countries. Higher gas prices and the need for cleaner fuels provides motivation for commercializing shale gas deposits even

  17. Shale gas exploitation: Status, problems and prospect

    Directory of Open Access Journals (Sweden)

    Shiqian Wang

    2018-02-01

    Full Text Available Over the past five years, great progress has been made in shale gas exploitation, which has become the most driving force for global gas output growth. Hydrocarbon extraction from shale helps drive the USA on the road to energy independence. Besides, shale oil & gas production has been kept in a sustained growth by continuous improvement in drilling efficiency and well productivity in the case of tumbling oil prices and rig counts. Shale gas reserves and production have been in a rapid growth in China owing to the Lower Paleozoic Wufeng and Longmaxi shale gas exploitation in the Sichuan Basin, which has become an important sector for the future increment of gas reserves and output in China. However, substantial progress has been made neither in non-marine shale gas exploitation as previously expected nor in the broad complicated tectonic areas in South China for which a considerable investment was made. Analysis of the basic situation and issues in domestic shale gas development shows that shale gas exploitation prospects are constrained by many problems in terms of resources endowment, horizontal well fracturing technology, etc. especially in non-marine shale deposits and complicated tectonic areas in South China where hot shales are widely distributed but geological structures are found severely deformed and over matured. Discussion on the prospects shows that the sustained and steady growth in shale gas reserves and production capacity in the coming years lies in the discovery and supersession of new shale plays in addition to Wufeng and Longmaxi shale plays, and that a technological breakthrough in ultra-high-pressure and ultra-deep (over 3500 m buried in the Sichuan Basin marine shale gas exploitation is the key and hope. Keywords: Shale gas, Exploitation, Marine facies, Hot shale, Resource endowment, Sichuan Basin, South China, Complicated tectonic area, Gas play

  18. Oil. The revenge of shales

    International Nuclear Information System (INIS)

    Dupin, Ludovic

    2017-01-01

    This article comments the evolutions noticed during these past years as the USA started to exploit non conventional hydrocarbons (shale gas and oil), and thus reduced their supplies from the Middle East. In reaction, OPEC members provoked a massive oil price decrease. If shale oil exploitation in the USA has slowed down for a while, it starts again: the number of platforms and production are increasing. Moreover, the profitability threshold is strongly decreasing. Argentina and China are also developing this sector, and Great-Britain and South-Africa are about to start projects. The article outlines that, even though France decided not to exploit shale gas and oil, French industries are present on this market and technology. In an interview, a representative of the French sector of non conventional hydrocarbons comments these evolutions as well as the French decision and its possible evolutions

  19. Process for treating oil shale

    Energy Technology Data Exchange (ETDEWEB)

    1920-08-22

    A process for treating oil shale is characterized in that the shale is first finely ground, then heated in the presence of steam in a high-pressure retort at 1 to 50 atmospheres pressure at a temperature of 200/sup 0/ to 450/sup 0/C and then with large amounts of water with or without materials forming emulsions with water or with oil. Solution medium suitable for bitumen or paraffin is beaten up in a rapid hammer mill until all or most all of the oil or bitumen is emulsified. The emulsion is separated by filter-pressing and centrifuging from the solid shale residue and the oil or bitumen is again separated from the emulsion medium by heating, acidulating, standing, or centrifuging, and then in known ways is further separated, refined, and worked up.

  20. Obtaining shale distillate free from sulphur

    Energy Technology Data Exchange (ETDEWEB)

    Heyl, G E

    1917-09-14

    A process whereby, from sulfur-containing shale, products free from sulfur may be obtained, consisting of mixing with the finely ground shale a portion of iron salts containing sufficient metal to unite with all the sulfur in the shale and form sulfide therewith, grinding the mixture to a fine state of subdivision and subsequently subjecting it to destructive distillation.

  1. Maquoketa Shale Caprock Integrity Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Leetaru, Hannes

    2014-09-30

    The Knox Project objective is to evaluate the potential of formations within the Cambrian-Ordovician strata above the Mt. Simon Sandstone (St. Peter Sandstone and Potosi Dolomite) as potential targets for carbon dioxide (CO2) sequestration in the Illinois and Michigan Basins. The suitability of the St. Peter Sandstone and Potosi Dolomite to serve as reservoirs for CO2 sequestration is discussed in separate reports. In this report the data gathered from the Knox project, the Illinois Basin – Decatur Project (IBDP) and Illinois Industrial Carbon Capture and Sequestration project (IL-ICCS) are used to make some conclusions about the suitability of the Maquoketa shale as a confining layer for CO2 sequestration. These conclusions are then upscaled to basin-wide inferences based on regional knowledge. Data and interpretations (stratigraphic, petrophysical, fractures, geochemical, risk, seismic) applicable to the Maquoketa Shale from the above mentioned projects was inventoried and summarized. Based on the analysis of these data and interpretations, the Maquoketa Shale is considered to be an effective caprock for a CO2 injection project in either the Potosi Dolomite or St. Peter Sandstone because it has a suitable thickness (~200ft. ~61m), advantageous petrophysical properties (low effective porosity and low permeability), favorable geomechanical properties, an absence of observable fractures and is regionally extensive. Because it is unlikely that CO2 would migrate upward through the Maquoketa Shale, CO2, impact to above lying fresh water aquifers is unlikely. Furthermore, the observations indicate that CO2 injected into the St. Peter Sandstone or Potosi Dolomite may never even migrate up into the Maquoketa Shale at a high enough concentrations or pressure to threaten the integrity of the caprock. Site specific conclusions were reached by unifying the data and conclusions from the IBDP, ICCS and the Knox projects. In the Illinois Basin, as one looks further away from

  2. Origin of Scottish oil shales

    Energy Technology Data Exchange (ETDEWEB)

    Conacher, H R.J.

    1916-12-01

    Oil shales contain two distinct types of organic material, one is comparable to the woody material in coal and the other consists of yellow bodies. When distilled, the latter yields the liquid product typical of oil shale, whereas the woody material produces large amounts of ammonia. The yellow bodies have been described by various investigators as fossil algae, spores, or dried-up globules of petroleum. In this study it was concluded that the yellow bodies were fragments of resins set free by the decay and oxidation of the vegetable matter with which they were originally associated.

  3. Tracing biosignatures from the Recent to the Jurassic in sabkha-associated microbial mats

    Science.gov (United States)

    van der Land, Cees; Dutton, Kirsten; Andrade, Luiza; Paul, Andreas; Sherry, Angela; Fender, Tom; Hewett, Guy; Jones, Martin; Lokier, Stephen W.; Head, Ian M.

    2017-04-01

    Microbial mat ecosystems have been operating at the sediment-fluid interface for over 3400 million years, influencing the flux, transformation and preservation of carbon from the biosphere to the physical environment. These ecosystems are excellent recorders of rapid and profound changes in earth surface environments and biota as they often survive crisis-induced extreme paleoenvironmental conditions. Their biosignatures, captured in the preserved organic matter and the biominerals that form the microbialite rock, constitute a significant tool in understanding geobiological processes and the interactions of the microbial communities with sediments and with the prevailing physical chemical parameters, as well as the environmental conditions at a local and global scale. Nevertheless, the exact pathways of diagenetic organic matter transformation and early-lithification, essential for the accretion and preservation in the geological record as microbialites, are not well understood. The Abu Dhabi coastal sabkha system contains a vast microbial mat belt that is dominated by continuous polygonal and internally-laminated microbial mats across the upper and middle intertidal zones. This modern system is believed to be the best analogue for the Upper Jurassic Arab Formation, which is both a prolific hydrocarbon reservoir and source rock facies in the United Arab Emirates and in neighbouring countries. In order to characterise the processes that lead to the formation of microbialites we investigated the modern and Jurassic system using a multidisciplinary approach, including growth of field-sampled microbial mats under controlled conditions in the laboratory and field-based analysis of microbial communities, mat mineralogy and organic biomarker analysis. In this study, we focus on hydrocarbon biomarker data obtained from the surface of microbial mats actively growing in the intertidal zone of the modern system. By comparing these findings to data obtained from recently

  4. Shale Gas characteristics of Permian black shales (Ecca group, Eastern Cape, South Africa)

    Science.gov (United States)

    Geel, Claire; Booth, Peter; Schulz, Hans-Martin; Horsfield, Brian; de Wit, Maarten

    2013-04-01

    This study involves a comprehensive and detailed lithological, sedimentalogical, structural and geochemical description of the lower Ecca Group in the Eastern Cape, South Africa. The Ecca group hosts a ~ 245 million year old organic-rich black shale, which has recently been the focus of interest of petroleum companies worldwide. The shale was deposited under anoxic conditions in a setting which formed as a consequence of retro-arc foreland basin development related to the Cape Fold Belt. This sedimentary/tectonic environment provided the conditions for deeply buried black shales to reach maturity levels for development in the gas window. The investigation site is called the Greystone Area and is situated north of Wolwefontein en route to Jansenville. The area has outcrops of the Dwyka, the Ecca and the lower Beaufort Groups. The outcrops were mapped extensively and the data was used in conjunction with GIS software to produce a detailed geological map. North-south cross sections were drawn to give indication of bed thicknesses and formation depths. Using the field work, data two boreholes were accurately sited on the northern limb of a shallow easterly plunging syncline. The first borehole reached 100m and the second was drilled to 292m depth (100m percussion and 192m core). The second borehole was drilled 200m south of the first, to penetrate the formations at a greater depth and to avoid surface weathering. Fresh core from the upper Dwyka Group, the Prince Albert Formation, the Whitehill Formation, Collingham Formation and part of the Ripon Formation were successfully extracted and a detailed stratigraphic log has been drawn up. The core was sampled during extraction and the samples were immediately sent to the GFZ in Potsdam, Germany, for geochemical analyses. As suspected the black shales of the the Whitehill Formation are high in organic carbon and have an average TOC value of 4.5%, whereas the Prince Albert and Collingham Formation are below 1%. Tmax values

  5. Tracking Early Jurassic marine (de)oxygenation

    Science.gov (United States)

    Them, T. R., II; Caruthers, A. H.; Gill, B. C.; Gröcke, D. R.; Marroquín, S. M.; Owens, J. D.

    2017-12-01

    It has been suggested that the carbon cycle was perturbed during the Toarcian OAE (T-OAE) as observed in the carbon isotope record, and more recently other elemental cycles (e.g., Hg, Mo, Os, S). The most widely accepted hypothesis focuses on the emplacement of the Karoo-Ferrar large igneous province, outgassing of greenhouse gases, and subsequent feedbacks in the Earth system, which caused severe environmental change and biological turnover. Feedbacks to elevated atmospheric pCO2 include enhanced weathering rates, dissociation of methane clathrates, increased terrestrial methanogenesis, and widespread marine anoxia. The sequence of events related to the development and duration of marine anoxia are not well constrained for this time interval due to a lack of open-ocean geochemical records. In order to reconstruct the timing of marine deoxygenation during the Early Jurassic T-OAE, we have utilized thallium isotopes, a novel geochemical proxy from multiple anoxic basins in North America and Germany. Three sites representing a basin transect from the Western Canada Sedimentary Basin, and one site from the South German Basin, were chosen to reconstruct the thallium isotopic composition (ɛ205Tl) of the ocean. The ɛ205Tl composition of sediments deposited under anoxic and euxinic water columns records the global seawater ɛ205Tl composition, a function of the amount of manganese oxides that are precipitated. Increased geographic extent of marine anoxia will cause a decrease in manganese oxide precipitation and perturb the thallium system. Importantly, the inputs of thallium are nearly identical, thus changes in these fluxes cannot drive the observed perturbation. Our new Early Jurassic ɛ205Tl records suggest that the onset of marine deoxygenation occurred concurrently with Karoo-Ferrar magmatism in the late Pliensbachian and continued until after the T-OAE. These new data support a Karoo-Ferrar trigger of the T-OAE. However, thallium isotopes also suggest that

  6. A new method for calculating gas saturation of low-resistivity shale gas reservoirs

    Directory of Open Access Journals (Sweden)

    Jinyan Zhang

    2017-09-01

    Full Text Available The Jiaoshiba shale gas field is located in the Fuling area of the Sichuan Basin, with the Upper Ordovician Wufeng–Lower Silurian Longmaxi Fm as the pay zone. At the bottom of the pay zone, a high-quality shale gas reservoir about 20 m thick is generally developed with high organic contents and gas abundance, but its resistivity is relatively low. Accordingly, the gas saturation calculated by formulas (e.g. Archie using electric logging data is often much lower than the experiment-derived value. In this paper, a new method was presented for calculating gas saturation more accurately based on non-electric logging data. Firstly, the causes for the low resistivity of shale gas reservoirs in this area were analyzed. Then, the limitation of traditional methods for calculating gas saturation based on electric logging data was diagnosed, and the feasibility of the neutron–density porosity overlay method was illustrated. According to the response characteristics of neutron, density and other porosity logging in shale gas reservoirs, a model for calculating gas saturation of shale gas was established by core experimental calibration based on the density logging value, the density porosity and the difference between density porosity and neutron porosity, by means of multiple methods (e.g. the dual-porosity overlay method by optimizing the best overlay coefficient. This new method avoids the effect of low resistivity, and thus can provide normal calculated gas saturation of high-quality shale gas reservoirs. It works well in practical application. This new method provides a technical support for the calculation of shale gas reserves in this area. Keywords: Shale gas, Gas saturation, Low resistivity, Non-electric logging, Volume density, Compensated neutron, Overlay method, Reserves calculation, Sichuan Basin, Jiaoshiba shale gas field

  7. Discovery of the early Jurassic Gajia mélange in the Bangong-Nujiang suture zone: Southward subduction of the Bangong-Nujiang Ocean?

    Science.gov (United States)

    Lai, Wen; Hu, Xiumian; Zhu, Dicheng; An, Wei; Ma, Anlin

    2017-06-01

    Mélange records a series of geological processes associated with oceanic subduction and continental collision. This paper reports for the first time the presence of Early Jurassic mélange from NW Nagqu in the southern margin of the Bangong-Nujiang suture zone, termed as the Gajia mélange. It shows typically blocks-in-matrix structure with matrix of black shale and siliceous mudstone, and several centimeters to several meters sized blocks of sandstone, silicalite, limestone and basalt. The sandstone blocks consist of homologous sandstone and two types of exotic sandstone, with different modal compositions. The Group 1 of exotic sandstone blocks consists of mainly of feldspar and quartz, whereas the Group 2 is rich in volcanic detritus. The Group 3 of homologous sandstone blocks is rich in feldspar and volcanic detritus with rare occurrence of quartz. U-Pb age data and in situ Hf isotopic compositions of detrital zircons from sandstone blocks are similar to those from the Lhasa terrane, suggesting that the sandstone blocks in the Gajia mélange most probably came from the Lhasa terrane. The YC1σ(2+) age of homologous sandstone blocks is 177 ± 2.4 Ma, suggesting an Early Jurassic depositional age for the sandstones within the Gajia mélange. The Gajia mélange likely records the southward subduction of the Bangong-Nujiang Ocean during the Early Jurassic.

  8. Annual monsoon rains recorded by Jurassic dunes.

    Science.gov (United States)

    Loope, D B; Rowe, C M; Joeckel, R M

    2001-07-05

    Pangaea, the largest landmass in the Earth's history, was nearly bisected by the Equator during the late Palaeozoic and early Mesozoic eras. Modelling experiments and stratigraphic studies have suggested that the supercontinent generated a monsoonal atmospheric circulation that led to extreme seasonality, but direct evidence for annual rainfall periodicity has been lacking. In the Mesozoic era, about 190 million years ago, thick deposits of wind-blown sand accumulated in dunes of a vast, low-latitude desert at Pangaea's western margin. These deposits are now situated in the southwestern USA. Here we analyse slump masses in the annual depositional cycles within these deposits, which have been described for some outcrops of the Navajo Sandstone. Twenty-four slumps, which were generated by heavy rainfall, appear within one interval representing 36 years of dune migration. We interpret the positions of 20 of these masses to indicate slumping during summer monsoon rains, with the other four having been the result of winter storms. The slumped lee faces of these Jurassic dunes therefore represent a prehistoric record of yearly rain events.

  9. First Jurassic grasshopper (Insecta, Caelifera) from China.

    Science.gov (United States)

    Gu, Jun-Jie; Yue, Yanli; Shi, Fuming; Tian, He; Ren, Dong

    2016-09-20

    Orthoptera is divided into two suborders, the Ensifera (katydids, crickets and mole crickets) and the Caelifera (grasshoppers and pygmy mole crickets). The earliest definitive caeliferans are those found in the Triassic (Bethoux & Ross 2005). The extinct caeliferan families, such as Locustopsidae and Locustavidae, may prove to be stem groups to some of the modern superfamilies (Grimaldi & Engel 2005). Locustopsidae is known from the Late Triassic or Early Jurassic to Late Cretaceous, consisting of two subfamilies (Gorochov et al. 2006). They are recorded from Europe, England, Russia, central Asia, China, Egypt, North America, Brazil and Australia. Up to now, Late Mesozoic fossil deposits of China has been reported plenty taxa of orthopterids, e.g. ensiferans, phasmatodeans, grylloblattids (Cui et al. 2012; Gu et al. 2010; Gu et al. 2012a; Gu et al. 2012b; Ren et al. 2012; Wang et al. 2014); but, with few caeliferans records, only four species, Pseudoacrida costata Lin 1982, Mesolocustopsis sinica Hong 1990, Tachacris stenosis Lin 1977 and T. turgis Lin 1980, were reported from the Early Cretaceous of Ningxia, Shandong, Yunnan and Zhejiang of China.

  10. Tellurium Enrichment in Jurassic Coal, Brora, Scotland

    Directory of Open Access Journals (Sweden)

    Liam Bullock

    2017-11-01

    Full Text Available Mid-Jurassic pyritic coals exposed at the village of Brora, northern Scotland, UK, contain a marked enrichment of tellurium (Te relative to crustal mean, average world coal compositions and British Isles Carboniferous coals. The Te content of Brora coal pyrite is more than one order of magnitude higher than in sampled pyrite of Carboniferous coals. The Te enrichment coincides with selenium (Se and mercury (Hg enrichment in the rims of pyrite, and Se/Te is much lower than in pyrites of Carboniferous coals. Initial pyrite formation is attributed to early burial (syn-diagenesis, with incorporation of Te, Se, Hg and lead (Pb during later pyrite formation. The source of Te may have been a local hydrothermal system which was responsible for alluvial gold (Au in the region, with some Au in Brora headwaters occurring as tellurides. Anomalous Te is not ubiquitous in coal, but may occur locally, and is detectable by laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS.

  11. Mechanical Characterization of Mancos Shale

    Science.gov (United States)

    Broome, S.; Ingraham, M. D.; Dewers, T. A.

    2015-12-01

    A series of tests on Mancos shale have been undertaken to determine the failure surface and to characterize anisotropy. This work supports additional studies which are being performed on the same block of shale; fracture toughness, permeability, and chemical analysis. Mechanical tests are being conducted after specimens were conditioned for at least two weeks at 70% constant relative humidity conditions. Specimens are tested under drained conditions, with the constant relative humidity condition maintained on the downstream side of the specimen. The upstream is sealed. Anisotropy is determined through testing specimens that have been cored parallel and perpendicular to the bedding plane. Preliminary results show that when loaded parallel to bedding the shale is roughly 50% weaker. Test are run under constant mean stress conditions when possible (excepting indirect tension, unconfined compression, and hydrostatic). Tests are run in hydrostatic compaction to the desired mean stress, then differential stress is applied axially in displacement control to failure. The constant mean stress condition is maintained by decreasing the confining pressure by half of the increase in the axial stress. Results will be compared to typical failure criteria to investigate the effectiveness of capturing the behavior of the shale with traditional failure theory. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. SAND2015-6107 A.

  12. Carbon cycle history through the Middle Jurassic (Aalenian - Bathonian) of the Mecsek Mountains, Southern Hungary

    Science.gov (United States)

    Price, Gregory D.; Főzy, István; Galácz, András

    2018-04-01

    A carbonate carbon isotope curve from the Aalenian-Bathonian interval is presented from the Óbánya valley, of the Mecsek Mountains, Hungary. This interval is certainly less well constrained and studied than other Jurassic time slices. The Óbánya valley lies in the eastern part of the Mecsek Mountains, between Óbánya and Kisújbánya and provides exposures of an Aalenian to Lower Cretaceous sequence. It is not strongly affected by tectonics, as compared to other sections of eastern Mecsek of the same age. In parts, a rich fossil assemblage has been collected, with Bathonian ammonites being especially valuable at this locality. The pelagic Middle Jurassic is represented by the Komló Calcareous Marl Formation and thin-bedded limestones of the Óbánya Limestone Formation. These are overlain by Upper Jurassic siliceous limestones and radiolarites of the Fonyászó Limestone Formation. Our new data indicate a series of carbon isotope anomalies within the late Aalenian and early-middle Bajocian. In particular, analysis of the Komló Calcareous Marl Formation reveals a negative carbon isotope excursion followed by positive values that occurs near the base of the section (across the Aalenian-Bajocian boundary). The origin of this carbon-isotope anomaly is interpreted to lie in significant changes to carbon fluxes potentially stemming from reduced run off, lowering the fertility of surface waters which in turn leads to lessened primary production and a negative δ13C shift. These data are comparable with carbonate carbon isotope records from other Tethyan margin sediments. Our integrated biostratigraphy and carbon isotope stratigraphy enable us to improve stratigraphic correlation and age determination of the examined strata. Therefore, this study of the Komló Calcareous Marl Formation confirms that the existing carbon isotope curves serve as a global standard for Aalenian-Bathonian δ13C variation.

  13. Carbon cycle history through the Middle Jurassic (Aalenian – Bathonian of the Mecsek Mountains, Southern Hungary

    Directory of Open Access Journals (Sweden)

    Price Gregory D.

    2018-04-01

    Full Text Available A carbonate carbon isotope curve from the Aalenian–Bathonian interval is presented from the Óbánya valley, of the Mecsek Mountains, Hungary. This interval is certainly less well constrained and studied than other Jurassic time slices. The Óbánya valley lies in the eastern part of the Mecsek Mountains, between Óbánya and Kisújbánya and provides exposures of an Aalenian to Lower Cretaceous sequence. It is not strongly affected by tectonics, as compared to other sections of eastern Mecsek of the same age. In parts, a rich fossil assemblage has been collected, with Bathonian ammonites being especially valuable at this locality. The pelagic Middle Jurassic is represented by the Komló Calcareous Marl Formation and thin-bedded limestones of the Óbánya Limestone Formation. These are overlain by Upper Jurassic siliceous limestones and radiolarites of the Fonyászó Limestone Formation. Our new data indicate a series of carbon isotope anomalies within the late Aalenian and early-middle Bajocian. In particular, analysis of the Komló Calcareous Marl Formation reveals a negative carbon isotope excursion followed by positive values that occurs near the base of the section (across the Aalenian–Bajocian boundary. The origin of this carbon-isotope anomaly is interpreted to lie in significant changes to carbon fluxes potentially stemming from reduced run off, lowering the fertility of surface waters which in turn leads to lessened primary production and a negative δ13C shift. These data are comparable with carbonate carbon isotope records from other Tethyan margin sediments. Our integrated biostratigraphy and carbon isotope stratigraphy enable us to improve stratigraphic correlation and age determination of the examined strata. Therefore, this study of the Komló Calcareous Marl Formation confirms that the existing carbon isotope curves serve as a global standard for Aalenian–Bathonian δ13C variation.

  14. Embryology of Early Jurassic dinosaur from China with evidence of preserved organic remains.

    Science.gov (United States)

    Reisz, Robert R; Huang, Timothy D; Roberts, Eric M; Peng, ShinRung; Sullivan, Corwin; Stein, Koen; LeBlanc, Aaron R H; Shieh, DarBin; Chang, RongSeng; Chiang, ChengCheng; Yang, Chuanwei; Zhong, Shiming

    2013-04-11

    Fossil dinosaur embryos are surprisingly rare, being almost entirely restricted to Upper Cretaceous strata that record the late stages of non-avian dinosaur evolution. Notable exceptions are the oldest known embryos from the Early Jurassic South African sauropodomorph Massospondylus and Late Jurassic embryos of a theropod from Portugal. The fact that dinosaur embryos are rare and typically enclosed in eggshells limits their availability for tissue and cellular level investigations of development. Consequently, little is known about growth patterns in dinosaur embryos, even though post-hatching ontogeny has been studied in several taxa. Here we report the discovery of an embryonic dinosaur bone bed from the Lower Jurassic of China, the oldest such occurrence in the fossil record. The embryos are similar in geological age to those of Massospondylus and are also assignable to a sauropodomorph dinosaur, probably Lufengosaurus. The preservation of numerous disarticulated skeletal elements and eggshells in this monotaxic bone bed, representing different stages of incubation and therefore derived from different nests, provides opportunities for new investigations of dinosaur embryology in a clade noted for gigantism. For example, comparisons among embryonic femora of different sizes and developmental stages reveal a consistently rapid rate of growth throughout development, possibly indicating that short incubation times were characteristic of sauropodomorphs. In addition, asymmetric radial growth of the femoral shaft and rapid expansion of the fourth trochanter suggest that embryonic muscle activation played an important role in the pre-hatching ontogeny of these dinosaurs. This discovery also provides the oldest evidence of in situ preservation of complex organic remains in a terrestrial vertebrate.

  15. Desulfurization of Jordanian oil shale

    International Nuclear Information System (INIS)

    Abu-Jdayil, B. M.

    1990-01-01

    Oxy desulfurization process and caustic treatment were applied in this work to remove sulfur from Jordanian oil shale. The oxy desulfurization process has been studied in a batch process using a high pressure autoclave, with constant stirring speed, and oxygen and water were used as desulfurizing reagents. Temperature, oxygen pressure, batch time, and particle size were found to be important process variables, while solid/liquid ratio was found to have no significant effect on the desulfurization process. The response of different types of oil shale to this process varied, and the effect of the process variables on the removal of total sulfur, pyritic sulfur, organic sulfur, total carbon, and organic carbon were studied. An optimum condition for oxy desulfurization of El-Lajjun oil shale, which gave maximum sulfur removal with low loss of carbon, was determined from the results of this work. The continuous reaction model was found to be valid, and the rate of oxidation for El-Lajjun oil shale was of the first order with respect to total sulfur, organic sulfur, total carbon, and organic carbon. For pyritic sulfur oxidation, the shrinking core model was found to hold and the rate of reaction controlled by diffusion through product ash layer. An activation energy of total sulfur, organic sulfur, pyritic sulfur, total carbon, and organic carbon oxidation was calculated for the temperature range of 130 -190 degrees celsius. In caustic treatment process, aqueous sodium hydroxide at 160 degrees celsius was used to remove the sulfur from El-Lajjun oil shale. The variables tested (sodium hydroxide concentration and treatment time) were found to have a significant effect. The carbon losses in this process were less than in the oxy desulfurization process. 51 refs., 64 figs., 121 tabs. (A.M.H.)

  16. The Jurassic of Denmark and Greenland: The Jurassic of East Greenland: a sedimentary record of thermal subsidence, onset and culmination of rifting

    Directory of Open Access Journals (Sweden)

    Surlyk, Finn

    2003-10-01

    Full Text Available The Late Palaeozoic – Mesozoic extensional basin complex of East Greenland contains a record of deposition during a period of Rhaetian – Early Bajocian thermal subsidence, the onset of riftingin the Late Bajocian, its growth during the Bathonian–Kimmeridgian, culmination of rifting in the Volgian – Early Ryazanian, and waning in the Late Ryazanian – Hauterivian. The area was centred over a palaeolatitude of about 45°N in the Rhaetian and drifted northwards to about 50°N in the Hauterivian. A major climate change from arid to humid subtropical conditions took place at the Norian–Rhaetian transition. Deposition was in addition governed by a long-term sea-level rise with highstands in the Toarcian–Aalenian, latest Callovian and Kimmeridgian, and lowstands in the latest Bajocian – earliest Bathonian, Middle Oxfordian and Volgian.The Rhaetian – Lower Bajocian succession is considered the upper part of a megasequence, termed J1, with its base in the upper Lower Triassic, whereas the Upper Bajocian – Hauterivian succession forms a complete, syn-rift megasequence, termed J2. The southern part of the basin complex in Jameson Land contains a relatively complete Rhaetian–Ryazanian succession and underwent only minor tilting during Middle Jurassic – earliest Cretaceous rifting. Rhaetian – Lower Jurassic deposits are absent north of Jameson Land and this region was fragmented into strongly tilted fault blocks during the protracted rift event. The syn-rift successions of the two areas accordingly show different long-term trends in sedimentary facies. In the southern area, the J2 syn-rift megasequence forms a symmetrical regressive–transgressive–regressive cycle, whereas the J2 megasequence in the northern area shows an asymmetrical, stepwise deepening trend.A total of eight tectonostratigraphic sequences are recognised in the Rhaetian–Hauterivian interval. They reflect major changes in basin configuration, drainage systems

  17. Animal behavior frozen in time: gregarious behavior of Early Jurassic lobsters within an ammonoid body chamber.

    Science.gov (United States)

    Klompmaker, Adiël A; Fraaije, René H B

    2012-01-01

    Direct animal behavior can be inferred from the fossil record only in exceptional circumstances. The exceptional mode of preservation of ammonoid shells in the Posidonia Shale (Lower Jurassic, lower Toarcian) of Dotternhausen in southern Germany, with only the organic periostracum preserved, provides an excellent opportunity to observe the contents of the ammonoid body chamber because this periostracum is translucent. Here, we report upon three delicate lobsters preserved within a compressed ammonoid specimen of Harpoceras falciferum. We attempt to explain this gregarious behavior. The three lobsters were studied using standard microscopy under low angle light. The lobsters belong to the extinct family of the Eryonidae; further identification was not possible. The organic material of the three small lobsters is preserved more than halfway into the ammonoid body chamber. The lobsters are closely spaced and are positioned with their tails oriented toward each other. The specimens are interpreted to represent corpses rather than molts. The lobsters probably sought shelter in preparation for molting or against predators such as fish that were present in Dotternhausen. Alternatively, the soft tissue of the ammonoid may have been a source of food that attracted the lobsters, or it may have served as a long-term residency for the lobsters (inquilinism). The lobsters represent the oldest known example of gregariousness amongst lobsters and decapods in the fossil record. Gregarious behavior in lobsters, also known for extant lobsters, thus developed earlier in earth's history than previously known. Moreover, this is one of the oldest known examples of decapod crustaceans preserved within cephalopod shells.

  18. Shaly sand evaluation using gamma ray spectrometry, applied to the North Sea Jurassic

    International Nuclear Information System (INIS)

    Marett, G.; Chevalier, P.; Souhaite, P.; Suau, J.

    1976-01-01

    In formations where radioactive minerals other than clay are present, their effects on log responses result in a reduction of the accuracy of determination of the shale fraction. The gamma ray log, which is one of the primary indicators for shaliness determination, is the most affected; other logs used in shaliness indicators are also influenced, particularly when heavy minerals are present, such as those encountered in the micaceous sandstones of the North Sea Jurassic. For comparison purposes, possible ways to correct for heavy radioactive minerals using a conventional logging suite are described. Computer processed examples illustrate the results obtained. A different approach is through an analysis of the natural gamma ray spectrum of the formation, as determined with the gamma ray spectrometry tool. Natural gamma rays originate from the radioactive isotope of potassium and the radioactive elements of the uranium and thorium series. Each of these three elements contributes its distinctive spectrum to that of the formation in proportion to its abundance. Thus, by analysis of the formation spectrum, the presence of each can be detected and its amount estimated. This makes possible quantitative corrections to the shaliness indicators. A computer program which performs the necessary computations is described, and several log examples using this technique are presented

  19. Breccia pipes in the Karoo Basin, South Africa, as conduits for metamorphic gases to the Early Jurassic atmosphere

    Science.gov (United States)

    Silkoset, Petter; Svensen, Henrik; Planke, Sverre

    2014-05-01

    The Toarcian (Early Jurassic) event was manifested by globally elevated temperatures and anoxic ocean conditions that particularly affected shallow marine taxa. The event coincided with the emplacement of the vast Karoo-Ferrar Large Igneous Province. Among the suggestions for trigger mechanisms for the climatic perturbation is metamorphic methane generation from black shale around the sills in the Karoo Basin, South Africa. The sill emplacement provides a mechanism for voluminous in-situ production and emission of greenhouse gases, and establishes a distinct link between basin-trapped and atmospheric carbon. In the lower stratigraphic levels of the Karoo Basin, black shales are metamorphosed around sills and the sediments are cut by a large number of pipe structures with metamorphic haloes. The pipes are vertical, cylindrical structures that contain brecciated and baked sediments with variable input of magmatic material. Here, we present borehole, petrographic, geochemical and field data from breccia pipes and contact aureoles based on field campaigns over a number of years (2004-2014). The metamorphism around the pipes show equivalent metamorphic grade as the sediments around nearby sills, suggesting a more prominent phreatomagmatic component than previously thought. The stratigraphic position of pipes and the breccia characteristics strengthens the hypothesis of a key role in the Toarcian carbon isotope excursion.

  20. Early Jurassic diversification of pycnodontiform fishes (Actinopterygii, Neopterygii) after the end-Triassic extinction event: evidence from a new genus and species, Grimmenodon aureum.

    Science.gov (United States)

    Stumpf, Sebastian; Ansorge, Jörg; Pfaff, Cathrin; Kriwet, Jürgen

    2017-07-04

    A new genus and species of pycnodontiform fishes, Grimmenodon aureum , from marginal marine, marine-brackish lower Toarcian ( Harpoceras exaratum ammonite subzone) clay deposits of Grimmen in northeastern Germany is described. The single specimen represents a diagnostic left prearticular dentition characterized by unique tooth arrangement and ornamentation patterns. Grimmenodon aureum , gen. et sp. nov., is the second unambiguously identified pycnodontiform species from the Early Jurassic, in addition to Eomesodon liassicus from the early Lower Jurassic of western Europe. We also report an indeterminate pycnodontiform tooth crown from the upper Pliensbachian ( Pleuroceras apyrenum ammonite subzone) of the same site. The material expands the Early Jurassic range of pycnodontiforms significantly northwards and confirms their presence before and immediately following the onset of the Toarcian Oceanic Anoxic Event (T-OAE) in the marginal marine ecosystems south of the Fennoscandian Shield. Moreover, the new records indicate that the Early Jurassic diversity of pycnodontiform fishes was greater than previously assumed and probably equaled that of the Late Triassic. Therefore, it is hypothesized that the Triassic-Jurassic mass extinction event did not affect pycnodontiform fishes significantly. Micro-computed tomography was used to study the internal anatomy of the prearticular of Grimmenodon aureum , gen. et sp. nov. Our results show that no replacement teeth were formed within the tooth-bearing bone but rather were added posteriorly to functional teeth. http://zoobank.org/urn:lsid:zoobank.org:pub:A56BDE9C-40C4-4CFA-9C2E-F5FA35A66F2 Citation for this article: Stumpf, S., J. Ansorge, C. Pfaff, and J. Kriwet. 2017. Early Jurassic diversification of pycnodontiform fishes (Actinopterygii, Neopterygii) after the end-Triassic extinction event: Evidence from a new genus and species, Grimmenodon aureum . Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2017.1344679.

  1. Paleoredoc and pyritization of soft-bodied fossils in the Ordovician Frankfort Shale of New York

    DEFF Research Database (Denmark)

    Farrell, Una C.; Briggs, Derek E. G.; Hammarlund, Emma U.

    2013-01-01

    Multiple beds in the Frankfort Shale (Upper Ordovician, New York State), including the original "Beecher's Trilobite Bed," yield fossils with pyritized soft-tissues. A bed-by-bed geochemical and sedimentological analysis was carried out to test previous models of soft-tissue pyritization...

  2. Petrophysics of shale intervals in the Skjold Field, Danish North Sea

    DEFF Research Database (Denmark)

    Mbia, Ernest Ncha; Fabricius, Ida Lykke; Oji, C. O.

    2011-01-01

    interval 6 is mainly shale. X-ray diffraction analysis reveals the dominance of inter-layered smectite/illite in interval 1–3 and upper part of interval 4, whereas illite dominates interval 5 and 6. Other minerals include kaolinite, chlorite, quartz, calcite, Opal-CT, dolomite and plagioclase...

  3. Reflectance measurements of zooclasts and solid bitumen in Lower Paleozoic shales, southern Scandinavia

    DEFF Research Database (Denmark)

    Petersen, Henrik I.; Schovsbo, Niels H.; Nielsen, Arne Thorshøj

    2013-01-01

    -like particles and graptolite fragments. The Middle Cambrian to Furongian (upper Cambrian) shales may contain sparse fragments of vase-shaped microfossils (VSM) that seem to follow the maturation trend of chitinozoans. In the present sample set, the reflectance of chitinozoans and VSM is comparable...

  4. Conversion characteristics of 10 selected oil shales

    Energy Technology Data Exchange (ETDEWEB)

    Miknis, F.P.

    1989-08-01

    The conversion behavior of 10 oil shale from seven foreign and three domestic deposits has been studied by combining solid- and liquid-state nuclear magnetic resonance (NMR) measurements with material balance Fischer assay conversion data. The extent of aromatization of aliphatic carbons was determined. Between zero and 42% of the raw shale aliphatic carbon formed aromatic carbon during Fischer assay. For three of the shales, there was more aromatic carbon in the residue after Fisher assay than in the raw shale. Between 10 and 20% of the raw shale aliphatic carbons ended up as aliphatic carbons on the spent shale. Good correlations were found between the raw shale aliphatic carbon and carbon in the oil and between the raw shale aromatic carbon and aromatic carbon on the spent shale. Simulated distillations and molecular weight determinations were performed on the shale oils. Greater than 50% of the oil consisted of the atmospheric and vacuum gas oil boiling fractions. 14 refs., 15 figs., 1 tab.

  5. Can Switching from Coal to Shale Gas Bring Net Carbon Reductions to China?

    Science.gov (United States)

    Qin, Yue; Edwards, Ryan; Tong, Fan; Mauzerall, Denise L

    2017-03-07

    To increase energy security and reduce emissions of air pollutants and CO 2 from coal use, China is attempting to duplicate the rapid development of shale gas that has taken place in the United States. This work builds a framework to estimate the lifecycle greenhouse gas (GHG) emissions from China's shale gas system and compares them with GHG emissions from coal used in the power, residential, and industrial sectors. We find the mean lifecycle carbon footprint of shale gas is about 30-50% lower than that of coal in all sectors under both 20 year and 100 year global warming potentials (GWP 20 and GWP 100 ). However, primarily due to large uncertainties in methane leakage, the upper bound estimate of the lifecycle carbon footprint of shale gas in China could be approximately 15-60% higher than that of coal across sectors under GWP 20 . To ensure net GHG emission reductions when switching from coal to shale gas, we estimate the breakeven methane leakage rates to be approximately 6.0%, 7.7%, and 4.2% in the power, residential, and industrial sectors, respectively, under GWP 20 . We find shale gas in China has a good chance of delivering air quality and climate cobenefits, particularly when used in the residential sector, with proper methane leakage control.

  6. Hydrogenation of Estonian oil shale and shale oil

    Energy Technology Data Exchange (ETDEWEB)

    Kogerman, P N; Kopwillem, J

    1932-01-01

    Kukersite was heated in an atmosphere of hydrogen, nitrogen, or water in three series of experiments. Shale samples were heated at 370/sup 0/ to 410/sup 0/C for 2 to 3/sup 1///sub 2/ hours in the presence of 106 to 287 kg/sq cm pressure of water, nitrogen, or hydrogen. In some experiments 5 percent of iron oxide was added to the shale. The amount of kerogen liquefied by hydrogenation was not greater than the amount of liquid products obtained by ordinary distillation. On hydrogenation, kukersite absorbed 1.8 weight-percent of hydrogen. Almost no hydrogenation took place below the decomposition point of kerogen, and the lighter decomposition products were mainly hydrogenated. Hydrogenation of the shale prevented coke formation. Heating kukersite or its crude oil at temperatures of 400/sup 0/ to 410/sup 0/C under 250 kg/sq cm hydrogen pressure produced paraffinic and naphthenic oils of lower boiling points. At higher temperatures and after long-continued heating, the formation of aromatic hydrocarbons was observed.

  7. Shale Oil Value Enhancement Research

    Energy Technology Data Exchange (ETDEWEB)

    James W. Bunger

    2006-11-30

    Raw kerogen oil is rich in heteroatom-containing compounds. Heteroatoms, N, S & O, are undesirable as components of a refinery feedstock, but are the basis for product value in agrochemicals, pharmaceuticals, surfactants, solvents, polymers, and a host of industrial materials. An economically viable, technologically feasible process scheme was developed in this research that promises to enhance the economics of oil shale development, both in the US and elsewhere in the world, in particular Estonia. Products will compete in existing markets for products now manufactured by costly synthesis routes. A premium petroleum refinery feedstock is also produced. The technology is now ready for pilot plant engineering studies and is likely to play an important role in developing a US oil shale industry.

  8. Process of distilling bituminous shale

    Energy Technology Data Exchange (ETDEWEB)

    Mayet, M

    1859-05-19

    This new process consists of placing at the end of a tube or the end of one or more retorts, an aspirating pump and compressor or a blower with two valves doing the same work or, better yet, a fan for sucking the vapor from the shale as it is formed in order to prevent its accumulating in the retorts and being decomposed. A second tube, pierced with little holes, placed in series with the pump, blower, or fan, acts as a vessel or receiver for the water. The vapors from the shale are compressed by the aspirator in the receiver for the water and condensed completely, without loss of gas and disinfect themselves for the most part.

  9. Recovering bituminous matter from shale

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, H D

    1922-08-29

    A process is described for obtaining valuable hydro-carbons from bituminous solids such as shale and the like, which comprises digesting a mixture of such a bituminous solid with a hydro-carbon liquid, the digestion being conducted at temperature high enough to effectively liquefy heavy bituminous matter contained in the solid but insufficiently high to effect substantial distillation of heavy bituminous matter, separating a resultant liquid mixture of hydrocarbons from the residue of such bituminous solid and refining the liquid mixture.

  10. Jurassic domes in the North Sea - northern North Atlantic region

    Energy Technology Data Exchange (ETDEWEB)

    Surlyk, F. [Univ. of Copenhagen, Geological Inst., Copenhagen (Denmark)

    1996-12-31

    The stratigraphic and tectonic evolution of the Jurassic of East Greenland, the Norwegian Shelf and the North Sea is remarkably similar. A major Middle Jurassic unconformity occurs in all three areas. In the North Sea it is commonly termed the `Mid-Cimmerian Unconformity` and is characterized by progressive truncation of the underlying section towards a centre at the triple junction between the Central Graben, Viking Graben and Moray Firth. Strata above the unconformity show a progressive Late Aalenian-Early Kimmeridgian onlap in the same direction. These relations have been interpreted as caused by Early Jurassic uplift and of a major thermal dome in the central North Sea, followed by Medial and Late Jurassic rifting, erosion, deflation and transgression of the dome. The East Greenland unconformity shows progressive truncation of underlying strata from south to north, and Bajocian to Callovian onlap in the same direction. The same pattern seems to be developed on the conjugate Norwegian margin. This suggests the possibility that the three unconformities have similar causes for their development. It is proposed that major rift domes formed in the Central North Sea and in the Greenland-Norway seaway in Early Jurassic times. The domes were eroded and gradually deflated during Medial Jurassic times and were finally submerged by the Late Oxfordian-Kimmeridgian. They were associated with volcanism and rifting which was delayed with respect to dome initiation. Roughly contemperaneous domes were present west of Britain, north of the Porcupine Seabight, and in Scania, southern Sweden, as reflected by development of asymmetrical unconformities showing progressive truncation of underlying strata, onlap of overlying Jurassic strata, and associated intrusive and extrusive volcanism. The domes are related to impingement of the heads of transient mantle plumes at the base of the lithosphere. The associated unconformities are thus of non-eustatic nature. Domal uplift and

  11. Shale oil. I. Genesis of oil shales and its relation to petroleum and other fuels

    Energy Technology Data Exchange (ETDEWEB)

    McKee, R H; Manning, P D.V.

    1927-01-01

    Oil-shale kerogen originated from resinous vegetation residues of past eras, whereas well petroleum was formed from oil shales by pressure and mild heat. Petroleum migrated to its present reservoir from neighboring oil-shale deposits, leaving a residue of black bituminous shales. The high carbon dioxide content of gases present in petroleum wells originated from kerogen, as it gives off carbon dioxide gas before producing soluble oil or bitumen.

  12. Quantifying porosity, compressibility and permeability in Shale

    DEFF Research Database (Denmark)

    Mbia, Ernest Ncha; Fabricius, Ida Lykke; Frykman, Peter

    strain data. We found that Kozeny's modelled permeability fall in the same order of magnitude with measured permeability for shale rich in kaolinite but overestimates permeability by two to three orders of magnitudes for shale with high content of smectite. The empirical Yang and Aplin model gives good...... permeability estimate comparable to the measured one for shale rich in smectite. This is probably because Yang and Aplin model was calibrated in London clay which is rich in smectite....

  13. Method and arrangement of distillation of shales

    Energy Technology Data Exchange (ETDEWEB)

    Bergh, S V

    1920-03-29

    A method is given of distilling shale and other bituminous materials utilizing the heat from the combustion of the residue, possibly with additional heat from other fuels. It is characterized by the shale, which is arranged in layers, being first submitted to a process of distillation utilizing the heat mentioned, and at the same time recovering the products of distillation, and second the shale being burned without disturbing the layers to any appreciable extent. The patent has 16 more claims.

  14. Preparation of cement from oil shale

    Energy Technology Data Exchange (ETDEWEB)

    1922-08-24

    A process for preparing cement from oil shale is described. The simultaneous recovery of shale oil by heating the oil shale formed into briquets with finely ground lime or limestone in a stream of hot gases is characterized by the fact that live steam or fine drops of water as preserving and carbonization means is introduced into the furnace, at the place, where the temperature of the briquet reaches about 500 to 600/sup 0/ C.

  15. Shale gas - the story of a deception

    International Nuclear Information System (INIS)

    Ambroise, Jacques

    2013-01-01

    This bibliographical sheet presents a book which aims at informing citizen about the irreversible consequences of shale gas exploitation on the environment, and about the economical and social aspects of an exploitation of this energy on a large scale. The author highlights the technical and environmental problems raised by hydraulic fracturing, outlines the complexity of the regulatory, legal and administrative framework, discusses the arguments which support shale gas exploitation, and outlines the importance of and energy transition without shale gas. The author notably outlines the conflicts of interest which pervert the debate on shale gas, notably within the French National Assembly

  16. A perspective on Canadian shale gas

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Mike; Davidson, Jim; Mortensen, Paul

    2010-09-15

    In a relatively new development over just the past few years, shale formations are being targeted for natural gas production. Based on initial results, there may be significant potential for shale gas in various regions of Canada, not only in traditional areas of conventional production but also non-traditional areas. However, there is much uncertainty because most Canadian shale gas production is currently in experimental or early developmental stages. Thus, its full potential will not be known for some time. If exploitation proves to be successful, Canadian shale gas may partially offset projected long-term declines in Canadian conventional natural gas production.

  17. Oil shale, shale oil, shale gas and non-conventional hydrocarbons

    Directory of Open Access Journals (Sweden)

    Clerici A.

    2015-01-01

    Full Text Available In recent years there has been a world “revolution” in the field of unconventional hydrocarbon reserves, which goes by the name of “shale gas”, gas contained inside clay sediments micropores. Shale gas finds particular development in the United States, which are now independent of imports and see a price reduction to less than one third of that in Europe. With the high oil prices, in addition to the non-conventional gas also “oil shales” (fine-grained sedimentary rocks that contain a large amount of organic material to be used both to be directly burned or to extract liquid fuels which go under the name of shale oil, extra heavy oils and bitumen are becoming an industrial reality. Both unconventional gas and oil reserves far exceed in the world the conventional oil and gas reserves, subverting the theory of fossil fuels scarcity. Values and location of these new fossil reserves in different countries and their production by comparison with conventional resources are presented. In view of the clear advantages of unconventional fossil resources, the potential environmental risks associated with their extraction and processing are also highlighted.

  18. Total petroleum systems of the Pelagian Province, Tunisia, Libya, Italy, and Malta; the Bou Dabbous, Tertiary and Jurassic-Cretaceous composite

    Science.gov (United States)

    Klett, T.R.

    2001-01-01

    Undiscovered conventional oil and gas resources were assessed within total petroleum systems of the Pelagian Province (2048) as part of the U.S. Geological Survey World Petroleum Assessment 2000. The Pelagian Province is located mainly in eastern Tunisia and northwestern Libya. Small portions of the province extend into Malta and offshore Italy. Although several petroleum systems may exist, only two ?composite? total petroleum systems were identified. Each total petroleum system comprises a single assessment unit. These total petroleum systems are called the Bou Dabbous?Tertiary and Jurassic-Cretaceous Composite, named after the source-rock intervals and reservoir-rock ages. The main source rocks include mudstone of the Eocene Bou Dabbous Formation; Cretaceous Bahloul, Lower Fahdene, and M?Cherga Formations; and Jurassic Nara Formation. Known reservoirs are in carbonate rocks and sandstone intervals throughout the Upper Jurassic, Cretaceous, and Tertiary sections. Traps for known accumulations include fault blocks, low-amplitude anticlines, high-amplitude anticlines associated with reverse faults, wrench fault structures, and stratigraphic traps. The estimated means of the undiscovered conventional petroleum volumes in total petroleum systems of the Pelagian Province are as follows: [MMBO, million barrels of oil; BCFG, billion cubic feet of gas; MMBNGL, million barrels of natural gas liquids] Total Petroleum System MMBO BCFG MMBNGL Bou Dabbous?Tertiary 667 2,746 64 Jurassic-Cretaceous Composite 403 2,280 27

  19. Biostratigraphic analysis of core samples from wells drilled in the Devonian shale interval of the Appalachian and Illinois Basins

    Energy Technology Data Exchange (ETDEWEB)

    Martin, S.J.; Zielinski, R.E.

    1978-07-14

    A palynological investigation was performed on 55 samples of core material from four wells drilled in the Devonian Shale interval of the Appalachian and Illinois Basins. Using a combination of spores and acritarchs, it was possible to divide the Middle Devonian from the Upper Devonian and to make subdivisions within the Middle and Upper Devonian. The age of the palynomorphs encountered in this study is Upper Devonian.

  20. Equatorial origin for Lower Jurassic radiolarian chert in the Franciscan Complex, San Rafael Mountains, southern California

    Science.gov (United States)

    Hagstrum, J.T.; Murchey, B.L.; Bogar, R.S.

    1996-01-01

    Lower Jurassic radiolarian chert sampled at two localities in the San Rafael Mountains of southern California (???20 km north of Santa Barbara) contains four components of remanent magnetization. Components A, B???, and B are inferred to represent uplift, Miocene volcanism, and subduction/accretion overprint magnetizations, respectively. The fourth component (C), isolated between 580?? and 680??C, shows a magnetic polarity stratigraphy and is interpreted as a primary magnetization acquired by the chert during, or soon after, deposition. Both sequences are late Pliensbachian to middle Toarcian in age, and an average paleolatitude calculated from all tilt-corrected C components is 1?? ?? 3?? north or south. This result is consistent with deposition of the cherts beneath the equatorial zone of high biologic productivity and is similar to initial paleolatitudes determined for chert blocks in northern California and Mexico. This result supports our model in which deep-water Franciscan-type cherts were deposited on the Farallon plate as it moved eastward beneath the equatorial productivity high, were accreted to the continental margin at low paleolatitudes, and were subsequently distributed northward by strike-slip faulting associated with movements of the Kula, Farallon, and Pacific plates. Upper Cretaceous turbidites of the Cachuma Formation were sampled at Agua Caliente Canyon to determine a constraining paleolatitude for accretion of the Jurassic chert sequences. These apparently unaltered rocks, however, were found to be completely overprinted by the A component of magnetization. Similar in situ directions and demagnetization behaviors observed in samples of other Upper Cretaceous turbidite sequences in southern and Baja California imply that these rocks might also give unreliable results.

  1. The Upper Danube Nature Park

    International Nuclear Information System (INIS)

    Dosedla, H.C.

    1997-01-01

    When in 1980 the Upper Danube Nature Park was founded as one of 65 nature sanctuaries in Germany there was great diversity of opinions concerning its intended character. The protected region consisting of a geologically outstanding landscape within central Europe is covering the first 80 km the upper Danube where the young river shortly after it's source in the Black Forest is breaking through the narrow canyons of the Jurassic rock plateau of the so-called Suebian Alps and also locates the subterranean passage where the stream is submerging from the surface for nearly ten miles. Since the purpose of nature preservation according to German las is closely combined with the rather contradicting aim of offering an attractive recreation area thus facing the immense impacts of modern mass tourism there are numerous problems which in the course of years have resulted in an intricate patterns of subtle management methods coping with the growing awareness of the ecological balance. (author)

  2. Chemical kinetics and oil shale process design

    Energy Technology Data Exchange (ETDEWEB)

    Burnham, A.K.

    1993-07-01

    Oil shale processes are reviewed with the goal of showing how chemical kinetics influences the design and operation of different processes for different types of oil shale. Reaction kinetics are presented for organic pyrolysis, carbon combustion, carbonate decomposition, and sulfur and nitrogen reactions.

  3. Oil shales and the nuclear process heat

    International Nuclear Information System (INIS)

    Scarpinella, C.A.

    1974-01-01

    Two of the primary energy sources most dited as alternatives to the traditional fossil fuels are oil shales and nuclear energy. Several proposed processes for the extraction and utilization of oil and gas from shale are given. Possible efficient ways in which nuclear heat may be used in these processes are discussed [pt

  4. Compaction Characteristics of Igumale Shale | Iorliam | Global ...

    African Journals Online (AJOL)

    This paper reports the outcome of an investigation into the effect of different compactive energies on the compaction characteristics of Igumale shale, to ascertain its suitability as fill material in highway ... The study showed that Igumale shale is not suitable for use as base, subbase and filling materials in road construction.

  5. Method of distillation of sulfurous bituminous shales

    Energy Technology Data Exchange (ETDEWEB)

    Hallback, A J.S.; Bergh, S V

    1918-04-22

    A method of distillation of sulfur-containing bituminous shales is characterized by passing the hot sulfur-containing and oil-containing gases and vapors formed during the distillation through burned shale containing iron oxide, so that when these gases and vapors are thereafter cooled they will be, as far as possible, free from sulfur compounds. The patent contains six more claims.

  6. Nitrogen fixation by legumes in retorted shale

    Energy Technology Data Exchange (ETDEWEB)

    Hersman, L E; Molitoris, E; Klein, D A

    1981-01-01

    A study was made to determine whether retorted shale additions would significantly affect symbiotic N/sub 2/ fixation. Results indicate that small additions of the shale may stimulate plant growth but with higher concentrations plants are stressed, resulting in a decreased biomass and a compensatory effect of an increased number of nodules and N/sub 2/ fixation potential. (JMT)

  7. Thermophysical properties of Conasauga shale

    International Nuclear Information System (INIS)

    Smith, D.D.

    1978-01-01

    Thermophysical-property characterizations of five Conasauga shale cores were determined at temperatures between 298 and 673 K. Methods of specimen fabrication for different tests were evaluated. Thermal-conductivity and thermal-expansion data were found to be dependent on the structure and orientation of the individual specimens. Thermal conductivities ranged between 2.8 and 1.0 W/m-K with a small negative temperature dependence. Thermal expansions were between 2 and 5 x 10 -3 over the temperature range for the group. Heat capacity varied with the composition. 17 figures, 3 tables

  8. Construction of Shale Gas Well

    Science.gov (United States)

    Sapińska-Śliwa, Aneta; Wiśniowski, Rafał; Skrzypaszek, Krzysztof

    2018-03-01

    The paper describes shale gas borehole axes trajectories (vertical, horizontal, multilateral). The methodology of trajectory design in a two-and three-dimensional space has been developed. The selection of the profile type of the trajectory axes of the directional borehole depends on the technical and technological possibilities of its implementation and the results of a comprehensive economic analysis of the availability and development of the field. The work assumes the possibility of a multivariate design of trajectories depending on the accepted (available or imposed) input data.

  9. Introduction to special section: China shale gas and shale oil plays

    Science.gov (United States)

    Jiang, Shu; Zeng, Hongliu; Zhang, Jinchuan; Fishman, Neil; Bai, Baojun; Xiao, Xianming; Zhang, Tongwei; Ellis, Geoffrey S.; Li, Xinjing; Richards-McClung, Bryony; Cai, Dongsheng; Ma, Yongsheng

    2015-01-01

    In the last 10 years, the success of shale gas and shale oil productions as a result of technological advances in horizontal drilling, hydraulic fracturing and nanoscale reservoir characterization have revolutionized the energy landscape in the United States. Resource assessment by the China Ministry of Land and Resources in 2010 and 2012 and by the U.S. Energy Information Administration in 2011 and 2013 indicates China’s shale gas resource is the largest in the world and shale oil resource in China is also potentially significant. Inspired by the success in the United States, China looks forward to replicating the U.S. experience to produce shale gas to power its economy and reduce greenhouse gas emissions. By 2014, China had drilled 400 wells targeting marine, lacustrine, and coastal swamp transitional shales spanning in age from the Precambrian to Cenozoic in the last five years. So far, China is the leading country outside of North America in the viable production of shale gas, with very promising prospects for shale gas and shale oil development, from the Lower Silurian Longmaxi marine shale in Fuling in the southeastern Sichuan Basin. Geological investigations by government and academic institutions as well as exploration and production activities from industry indicate that the tectonic framework, depositional settings, and geomechanical properties of most of the Chinese shales are more complex than many of the producing marine shales in the United States. These differences limit the applicability of geologic analogues from North America for use in Chinese shale oil and gas resource assessments, exploration strategies, reservoir characterization, and determination of optimal hydraulic fracturing techniques. Understanding the unique features of the geology, shale oil and gas resource potential, and reservoir characteristics is crucial for sweet spot identification, hydraulic fracturing optimization, and reservoir performance prediction.

  10. Different Methods of Predicting Permeability in Shale

    DEFF Research Database (Denmark)

    Mbia, Ernest Ncha; Fabricius, Ida Lykke; Krogsbøll, Anette

    by two to five orders of magnitudes at lower vertical effective stress below 40 MPa as the content of clay minerals increases causing heterogeneity in shale material. Indirect permeability from consolidation can give maximum and minimum values of shale permeability needed in simulating fluid flow......Permeability is often very difficult to measure or predict in shale lithology. In this work we are determining shale permeability from consolidation tests data using Wissa et al., (1971) approach and comparing the results with predicted permeability from Kozeny’s model. Core and cuttings materials...... effective stress to 9 μD at high vertical effective stress of 100 MPa. The indirect permeability calculated from consolidation tests falls in the same magnitude at higher vertical effective stress, above 40 MPa, as that of the Kozeny model for shale samples with high non-clay content ≥ 70% but are higher...

  11. Intelligent fracture creation for shale gas development

    KAUST Repository

    Douglas, Craig C.

    2011-05-14

    Shale gas represents a major fraction of the proven reserves of natural gas in the United States and a collection of other countries. Higher gas prices and the need for cleaner fuels provides motivation for commercializing shale gas deposits even though the cost is substantially higher than traditional gas deposits. Recent advances in horizontal drilling and multistage hydraulic fracturing, which dramatically lower costs of developing shale gas fields, are key to renewed interest in shale gas deposits. Hydraulically induced fractures are quite complex in shale gas reservoirs. Massive, multistage, multiple cluster treatments lead to fractures that interact with existing fractures (whether natural or induced earlier). A dynamic approach to the fracturing process so that the resulting network of reservoirs is known during the drilling and fracturing process is economically enticing. The process needs to be automatic and done in faster than real-time in order to be useful to the drilling crews.

  12. Nitrogen fixation by legumes in retorted shale

    Energy Technology Data Exchange (ETDEWEB)

    Hersman, L E; Molitoris, E; Klein, D A

    1981-01-01

    Although a soil-shale mixture was employed as the growth medium in this experiment, the results presentd are applicable to the proposed method of disposal mentioned earlier. Under field conditions, when covering the retorted shale with topsoil, some mixing of these materials might occur in the plant root region. In addition, it has been demonstrated that buried shale negatively affects enzyme activities in overburden surface soil. The occurrence of either of those events could affect symbiotic N/sub 2/ fixation in a manner similar to that reported in this paper. Researchers conclude that due to the varied effects of retorted shale on the legumes tested, further evaluation of other legumes may be necessary. Additional research would be required to determine which legumes have potential use for reclamation of retorted shale.

  13. Lower Silurian `hot shales' in North Africa and Arabia: regional distribution and depositional model

    Science.gov (United States)

    Lüning, S.; Craig, J.; Loydell, D. K.; Štorch, P.; Fitches, B.

    2000-03-01

    Lowermost Silurian organic-rich (`hot') shales are the origin of 80-90% of Palaeozoic sourced hydrocarbons in North Africa and also played a major role in petroleum generation on the Arabian Peninsula. In most cases, the shales were deposited directly above upper Ordovician (peri-) glacial sandstones during the initial early Silurian transgression that was a result of the melting of the late Ordovician icecap. Deposition of the main organic-rich shale unit in the North African/Arabian region was restricted to the earliest Silurian Rhuddanian stage ( acuminatus, atavus and probably early cyphus graptolite biozones). During this short period (1-2 m.y.), a favourable combination of factors existed which led to the development of exceptionally strong oxygen-deficiency in the area. In most countries of the study area, the post-Rhuddanian Silurian shales are organically lean and have not contributed to petroleum generation. The distribution and thickness of the basal Silurian `hot' shales have been mapped in detail for the whole North African region, using logs from some 300 exploration wells in Libya, Tunisia, Algeria and Morocco. In addition, all relevant, accessible published and unpublished surface and subsurface data of the lower Silurian shales in North Africa and Arabia have been reviewed, including sedimentological, biostratigraphic and organic geochemical data. The lowermost Silurian hot shales of northern Gondwana are laterally discontinuous and their distribution and thickness were controlled by the early Silurian palaeorelief which was shaped mainly by glacial processes of the late Ordovician ice age and by Pan-African and Infracambrian compressional and extensional tectonism. The thickest and areally most extensive basal Silurian organic-rich shales in North Africa occur in Algeria, Tunisia and western Libya, while on the Arabian Peninsula they are most prolific in Saudi Arabia, Oman, Jordan and Iraq. The hot shales were not deposited in Egypt, which was a

  14. Relation of peat to oil shale

    Energy Technology Data Exchange (ETDEWEB)

    Linker, S

    1924-01-01

    Samples of oil shale from the Green River formation and from Elko (Nev.), Brazil, Austria, and South Africa were examined, and several varieties of shale were found. Green River oil shale represents three of the more common types plus one less common type. These were: contorted shale with a velvety appearance, thin paper shale resembling the curled-up leaves of a book, massive black shale resembling a piece of rubber, and a less common type, which showed the bedding planes very clearly. The Elko (Nev.) shale was a light buff color; the shale from Brazil resembled a piece of petrified peat. When the shales were cut very thin, their colors ranged from yellow to reddish-brown. The composition, as seen under the microscope, was of well-preserved plant material such as spores, pollen grains, fragments of cell tissues, algae, fungi, bacteria, macerated organic residue, small pieces of resin, animal fossils, and translucent bodies. Oil shale was produced from organic material that accumulated in peat bogs, marshes, or swamps in fresh or salt waters. The organic matter was decomposed by bacterial action. Certain parts of the plants decayed more readily than others. Before lithification occurred, a chemical action took place that changed the softer tissues of the plant debris into a gel. This collodial matter penetrated and surrounded the more resistant fragments and preserved them from further decay. Certain bog waters contain a high percentage of humic acids in solution or collodial suspension and produce insoluble humates when neutralized. These humates are probably the so-called kerogen bodies.

  15. The Jurassic of Denmark and Greenland: Sedimentology and sequence stratigraphy of the Bryne and Lulu Formations, Middle Jurassic, northern Danish Central Graben

    Directory of Open Access Journals (Sweden)

    Andsbjerg, Jan

    2003-10-01

    Full Text Available The Middle Jurassic Bryne and Lulu Formations of the Søgne Basin (northern part of the Danish Central Graben consist of fluvially-dominated coastal plain deposits, overlain by interfingering shoreface and back-barrier deposits. Laterally continuous, mainly fining-upwards fluvial channel sandstones that locally show evidence for tidal influence dominate the alluvial/coastal plain deposits of the lower Bryne Formation. The sandstones are separated by units of fine-grained floodplain sediments that show a fining-upwards - coarsening-upwards pattern and locally grade into lacustrine mudstones. A regional unconformity that separates the lower Bryne Formation from the mainly estuarine upper Bryne Formation is defined by the strongly erosional base of a succession of stacked channel sandstones, interpreted as the fill of a system of incised valleys. Most of the stacked channel sandstones show abundant mud laminae and flasers, and rare herringbone structures, suggesting that they were deposited in a tidal environment, probably an estuary. Several tens of metres of the lower Bryne Formation may have been removed by erosion at this unconformity. The estuarine channel sandstone succession is capped by coal beds that attain a thickness of several metres in the western part of the Søgne Basin, but are thin and poorly developed in the central part of the basin. Above the coal beds, the Lulu Formation is dominated by various types of tidally influenced paralic deposits in the western part of the basin and by coarsening-upwards shoreface and beach deposits in central parts. Westwards-thickening wedges of paralic deposits interfinger with eastwards-thickening wedges of shallow marine deposits. The Middle Jurassic succession is subdivided into nine sequences. In the lower Bryne Formation, sequence boundaries are situated at the base of laterally continuous fluvial channel sandstones whereas maximum flooding surfaces are placed in laterally extensive floodplain

  16. Effects of experimental parameters on the sorption of cesium, strontium, and uranium from saline groundwaters onto shales: Progress report

    International Nuclear Information System (INIS)

    Meyer, R.E.; Arnold, W.D.; Case, F.I.; O'Kelley, G.D.

    1988-11-01

    This report concerns an extension of the first series of experiments on the sorption properties of shales and their clay mineral components reported earlier. Studies on the sorption of cesium and strontium were carried out on samples of Chattanooga (Upper Dowelltown), Pierre, Green River Formation, Nolichucky, and Pumpkin Valley Shales that had been heated to 120/degree/C in a 0.1-mol/L NaCl solution for periods up to several months and on samples of the same shales which had been heated to 250/degree/C in air for six months, to simulate limiting scenarios in a HLW repository. To investigate the kinetics of the sorption process in shale/groundwater systems, strontium sorption experiments were done on unheated Pierre, Green River Formation, Nolichucky, and Pumpkin Valley Shales in a diluted, saline groundwater and in 0.03-mol/L NaHCO 3 , for periods of 0.25 to 28 days. Cesium sorption kinetics tests were performed on the same shales in a concentrated brine for the same time periods. The effect of the water/rock (W/R) ratio on sorption for the same combinations of unheated shales, nuclides, and groundwaters used in the kinetics experiments was investigated for a range of W/R ratios of 3 to 20 mL/g. Because of the complexity of the shale/groundwater interaction, a series of tests was conducted on the effects of contact time and W/R ratio on the pH of a 0.03-mol/L NaHCO 3 simulated groundwater in contact with shales. 8 refs., 12 figs., 15 tabs

  17. Diversity and paleogeographic distribution of Early Jurassic plesiosaurs

    Science.gov (United States)

    Vincent, Peggy; Suan, Guillaume

    2010-05-01

    Early Jurassic plesiosaurs, a group of extinct marine reptiles, were one of the first groups to be described in the history of vertebrate paleontology. Nevertheless, the paleogeographic distribution and the taxonomic diversity of these forms are still unclear, particularly because most descriptions and taxonomic attributions were realized during the mid 19th to early 20th century. Here we investigate the paleodiversity and paleogeographic distribution of Early Jurassic plesiosaurs using an extensive taxonomic and anatomical revision of most known Early Jurassic specimens. We also present an examination of the biostratigraphic and sedimentological framework of deposits in which these specimens were discovered, in order to decipher whether their fossil record reflects primary paleobiological trends or taphonomic/discovery biases. Early Jurassic Plesiosaur diversity appears to reach its maximum during the Toarcian (falciferum-bifrons ammonite zones). Nevertheless, the inclusion of ghost lineages into the diversity curves indicates that this pattern likely reflects discovery and taphonomical biases rather than primary biodiversity trends. Indeed, most strata where numerous plesiosaurs species were discovered correspond to sediments that were deposited under poorly-oxygenated conditions and exploited at least in a semi-industrial way during the 1800's-1950's. The Lower Jurassic fossiliferous localities that yielded identifiable plesiosaur species are only found in Western Europe (England, Germany, and France). In Europe, the Toarcian stage is the only interval where more than one fossiliferous locality is known (the Hettangian, Sinemurian and Pliensbachian stages being each represented by only one locality where specimens are identifiable at the species level). The different Toarcian fossiliferous sites of Europe do not bear any single common taxon, suggesting a high degree of endemism in Early Jurassic plesiosaurs. Nevertheless, these sites are fundamentally

  18. Preparation of hydraulic cement from oil-shale

    Energy Technology Data Exchange (ETDEWEB)

    1921-08-28

    A process for the preparation of hydraulic cement from oil-shale or oil-shale residue is characterized in that, the oil-shale or shale-coke together with a slight amount of marl is burned under sintering conditions and the residue obtained is ground to a fine dust.

  19. Animal behavior frozen in time: gregarious behavior of Early Jurassic lobsters within an ammonoid body chamber.

    Directory of Open Access Journals (Sweden)

    Adiël A Klompmaker

    Full Text Available Direct animal behavior can be inferred from the fossil record only in exceptional circumstances. The exceptional mode of preservation of ammonoid shells in the Posidonia Shale (Lower Jurassic, lower Toarcian of Dotternhausen in southern Germany, with only the organic periostracum preserved, provides an excellent opportunity to observe the contents of the ammonoid body chamber because this periostracum is translucent. Here, we report upon three delicate lobsters preserved within a compressed ammonoid specimen of Harpoceras falciferum. We attempt to explain this gregarious behavior. The three lobsters were studied using standard microscopy under low angle light. The lobsters belong to the extinct family of the Eryonidae; further identification was not possible. The organic material of the three small lobsters is preserved more than halfway into the ammonoid body chamber. The lobsters are closely spaced and are positioned with their tails oriented toward each other. The specimens are interpreted to represent corpses rather than molts. The lobsters probably sought shelter in preparation for molting or against predators such as fish that were present in Dotternhausen. Alternatively, the soft tissue of the ammonoid may have been a source of food that attracted the lobsters, or it may have served as a long-term residency for the lobsters (inquilinism. The lobsters represent the oldest known example of gregariousness amongst lobsters and decapods in the fossil record. Gregarious behavior in lobsters, also known for extant lobsters, thus developed earlier in earth's history than previously known. Moreover, this is one of the oldest known examples of decapod crustaceans preserved within cephalopod shells.

  20. Paleoenvironmental conditions across the Jurassic-Cretaceous boundary in central-eastern Mexico

    Science.gov (United States)

    Martínez-Yáñez, Mario; Núñez-Useche, Fernando; López Martínez, Rafael; Gardner, Rand D.

    2017-08-01

    The Padni section of central-eastern Mexico is characterized by pelagic, organic-rich carbonates and shales dated in this study by calpionellid biostratigraphy to the late Tithonian-late Berriasian time interval. Microfacies, pyrite framboid size, spectrometric gamma-ray and mineralogical data are herein integrated in order to reconstruct the paleoenvironmental change during the Jurassic-Cretaceous boundary. Deposits of the late Tithonian-early Berriasian are characterized by laminated, organic-rich facies with abundant radiolarian, tiny pyrite framboids and low Th/U ratios. They are linked to upwelling in a semi-restricted basin, high marine productivity and anoxic bottom waters. The early incursions of Tethyan oceanic waters into the proto-Gulf of Mexico occurred during late Tithonian as attested the appearance of calpionellids. Short and intermittent accumulations of saccocomids during early Berriasian suggest episodes of sporadic connection between the Tethys, the proto-Atlantic and the Pacific ocean during sea-level rise events. A full and stable connection between the Tethys and proto-Gulf of Mexico was established until the late Berriasian. This event is supported by the presence of open marine and bioturbated facies with a framboid population typical of dysoxic conditions, higher Th/U ratios and a decreasing pattern of the total organic carbon content. In addition to highlighting the replenishment of the oxygen supply to the basin, this facies also points to a younger age for the finalization of the Yucatán Block rotation and the end of the Gulf of Mexico opening. Deposition of the studied section occurred mostly during a Tithonian-Berriasian arid phase reported in other Tethyan and Atlantic regions. The similarity between the discrete segments of the standard gamma-ray curve defined in the studied outcrop and those reported from subsurface implies their regional continuity allowing their use for correlation purposes.

  1. A review of the organic geochemistry of shales

    International Nuclear Information System (INIS)

    Ho, P.C.; Meyer, R.E.

    1987-06-01

    Shale formations have been suggested as a potential site for a high level nuclear waste repository. As a first step in the study of the possible interaction of nuclides with the organic components of the shales, literature on the identification of organic compounds from various shales of the continent of the United States has been reviewed. The Green River shale of the Cenozoic era is the most studied shale followed by the Pierre shale of the Mesozoic era and the Devonian black shale of the Paleozoic era. Organic compounds that have been identified from these shales are hydrocarbons, fatty acids, fatty alcohols, steranes, terpanes, carotenes, carbohydrates, amino acids, and porphyrins. However, these organic compounds constitute only a small fraction of the organics in shales and the majority of the organic compounds in shales are still unidentified

  2. A mysterious giant ichthyosaur from the lowermost Jurassic of Wales

    Directory of Open Access Journals (Sweden)

    Jeremy E. Martin

    2015-12-01

    Full Text Available Ichthyosaurs rapidly diversified and colonised a wide range of ecological niches during the Early and Middle Triassic period, but experienced a major decline in diversity near the end of the Triassic. Timing and causes of this demise and the subsequent rapid radiation of the diverse, but less disparate, parvipelvian ichthyosaurs are still unknown, notably because of inadequate sampling in strata of latest Triassic age. Here, we describe an exceptionally large radius from Lower Jurassic deposits at Penarth near Cardiff, south Wales (UK the morphology of which places it within the giant Triassic shastasaurids. A tentative total body size estimate, based on a regression analysis of various complete ichthyosaur skeletons, yields a value of 12–15 m. The specimen is substantially younger than any previously reported last known occurrences of shastasaurids and implies a Lazarus range in the lowermost Jurassic for this ichthyosaur morphotype.

  3. Geochemical behavior of Cs, Sr, Tc, Np, and U in saline groundwaters: Sorption experiments on shales and their clay mineral components: Progress report

    International Nuclear Information System (INIS)

    Meyer, R.E.; Arnold, W.D.; Ho, P.C.; Case, F.I.; O'Kelley, G.D.

    1987-11-01

    The Sedimentary Rock Program at the Oak Ridge National Laboratory is investigating shale to determine its potential suitability as a host rock for the disposal of high-level radioactive wastes (HLW). In support of this program, preliminary studies were carried out on sorption of cesium, strontium, technetium, neptunium, and uranium onto Chattanooga (Upper Dowelltown), Pierre, Green River Formation, Nolichucky, and Pumpkin Valley Shales under oxic conditions (air present). Three simulated groundwaters were used. One of the groundwaters was a synthetic brine made up to simulate highly saline groundwaters in the Pumpkin Valley Shale. The second was a 100/1 dilution of this groundwater and the third was 0.03 M NaHCO 3 . Moderate to significant sorption was observed under most conditions for all of the tested radionuclides except technetium. Moderate technetium sorption occurred on Upper Dowelltown Shale, and although technetium sorption was low on the other shales, it was higher than expected for Tc(VII), present as the anion TcO 4 - . Little sorption of strontium onto the shales was observed from the concentrated saline groundwater. These data can be used in a generic fashion to help assess the sorption characteristics of shales in support of a national survey. 10 refs., 4 figs., 23 tabs

  4. Production of oil from Israeli oil shale

    International Nuclear Information System (INIS)

    Givoni, D.

    1993-01-01

    Oil shale can be utilized in two-ways: direct combustion to generate steam and power or retorting to produce oil or gas. PAMA has been developing both direct combustion and retorting processes. Its main effort is in the combustion. An oil shale fired steam boiler was erected in the Rotem industrial complex for demonstration purposes. PAMA has also been looking into two alternative retorting concepts - slow heating of coarse particles and fast heating of fine particles. The present paper provides operating data of oil shale processing in the following scheme: (a) retorting in moving bed, pilot and bench scale units, and (b) retorting in a fluidized bed, bench scale units. (author)

  5. The real hazards of shale gas

    International Nuclear Information System (INIS)

    Favari, Daniele; Picot, Andre; Durand, Marc

    2013-01-01

    This bibliographical sheet presents a book which addresses the issue of shale gas. A first part describes the origin of this gaseous hydrocarbon, the composition of shale gas and its extraction, the technique of hydraulic fracturing, and the environmental risks. A second part addresses the economic, ecologic and political issues. The authors outline that all signs are there to prove the alarming hazards of shale gas. One of the authors outlines the necessity of an energy transition, far from fossil and nuclear energy, in order to guarantee a high level of protection of human health and of the environment

  6. Method of recovering hydrocarbons from oil shale

    Energy Technology Data Exchange (ETDEWEB)

    Walton, D.K.; Slusser, M.S.

    1970-11-24

    A method is described for recovering hydrocarbons from an oil-shale formation by in situ retorting. A well penetrating the formation is heated and gas is injected until a pressure buildup within the well is reached, due to a decrease in the conductivity of naturally occurring fissures within the formation. The well is then vented, in order to produce spalling of the walls. This results in the formation of an enlarged cavity containing rubberized oil shale. A hot gas then is passed through the rubberized oil shale in order to retort hydrocarbons and these hydrocarbons are recovered from the well. (11 claims)

  7. Investigation of the dielectric properties of shale

    International Nuclear Information System (INIS)

    Martemyanov, Sergey M.

    2011-01-01

    The article is dedicated to investigation of the dielectric properties of oil shale. Investigations for samples prepared from shale mined at the deposit in Jilin Province in China were done. The temperature and frequency dependences of rock characteristics needed to calculate the processes of their thermal processing are investigated. Frequency dependences for the relative dielectric constant and dissipation factor of rock in the frequency range from 0,1 Hz to 1 MHz are investigated. The temperature dependences for rock resistance, dielectric capacitance and dissipation factor in the temperature range from 20 to 600°C are studied. Key words: shale, dielectric properties, relative dielectric constant, dissipation factor, temperature dependence, frequency dependence

  8. Selection of logging-based TOC calculation methods for shale reservoirs: A case study of the Jiaoshiba shale gas field in the Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Renchun Huang

    2015-03-01

    Full Text Available Various methods are available for calculating the TOC of shale reservoirs with logging data, and each method has its unique applicability and accuracy. So it is especially important to establish a regional experimental calculation model based on a thorough analysis of their applicability. With the Upper Ordovician Wufeng Fm-Lower Silurian Longmaxi Fm shale reservoirs as an example, TOC calculation models were built by use of the improved ΔlgR, bulk density, natural gamma spectroscopy, multi-fitting and volume model methods respectively, considering the previous research results and the geologic features of the area. These models were compared based on the core data. Finally, the bulk density method was selected as the regional experimental calculation model. Field practices demonstrated that the improved ΔlgR and natural gamma spectroscopy methods are poor in accuracy; although the multi-fitting method and bulk density method have relatively high accuracy, the bulk density method is simpler and wider in application. For further verifying its applicability, the bulk density method was applied to calculate the TOC of shale reservoirs in several key wells in the Jiaoshiba shale gas field, Sichuan Basin, and the calculation accuracy was clarified with the measured data of core samples, showing that the coincidence rate of logging-based TOC calculation is up to 90.5%–91.0%.

  9. Impact of Oxidative Dissolution on Black Shale Fracturing: Implication for Shale Fracturing Treatment Design

    Science.gov (United States)

    You, L.; Chen, Q.; Kang, Y.; Cheng, Q.; Sheng, J.

    2017-12-01

    Black shales contain a large amount of environment-sensitive compositions, e.g., clay minerals, carbonate, siderite, pyrite, and organic matter. There have been numerous studies on the black shales compositional and pore structure changes caused by oxic environments. However, most of the studies did not focus on their ability to facilitate shale fracturing. To test the redox-sensitive aspects of shale fracturing and its potentially favorable effects on hydraulic fracturing in shale gas reservoirs, the induced microfractures of Longmaxi black shales exposed to deionized water, hydrochloric acid, and hydrogen peroxide at room-temperature for 240 hours were imaged by scanning electron microscopy (SEM) and CT-scanning in this paper. Mineral composition, acoustic emission, swelling, and zeta potential of the untreated and oxidative treatment shale samples were also recorded to decipher the coupled physical and chemical effects of oxidizing environments on shale fracturing processes. Results show that pervasive microfractures (Fig.1) with apertures ranging from tens of nanometers to tens of microns formed in response to oxidative dissolution by hydrogen peroxide, whereas no new microfracture was observed after the exposure to deionized water and hydrochloric acid. The trajectory of these oxidation-induced microfractures was controlled by the distribution of phyllosilicate framework and flaky or stringy organic matter in shale. The experiments reported in this paper indicate that black shales present the least resistance to crack initiation and subcritical slow propagation in hydrogen peroxide, a process we refer to as oxidation-sensitive fracturing, which are closely related to the expansive stress of clay minerals, dissolution of redox-sensitive compositions, destruction of phyllosilicate framework, and the much lower zeta potential of hydrogen peroxide solution-shale system. It could mean that the injection of fracturing water with strong oxidizing aqueous solution may

  10. Refining shale-oil distillates

    Energy Technology Data Exchange (ETDEWEB)

    Altpeter, J

    1952-03-17

    A process is described for refining distillates from shale oil, brown coal, tar, and other tar products by extraction with selective solvents, such as lower alcohols, halogen-hydrins, dichlorodiethyl ether, liquid sulfur dioxide, and so forth, as well as treating with alkali solution, characterized in that the distillate is first treated with completely or almost completely recovered phenol or cresotate solution, the oil is separated from the phenolate with solvent, for example concentrated or adjusted to a determined water content of lower alcohol, furfural, halogen-hydrin, dichlorodiethyl ether, liquid sulfur dioxide, or the like, extracted, and the raffinate separated from the extract layer, if necessary after distillation or washing out of solvent, and freeing with alkali solution from residual phenol or creosol.

  11. Shale gas, a hazardous exploitation

    International Nuclear Information System (INIS)

    Maincent, G.

    2011-01-01

    In march 2010 three authorizations to search for shale gases were delivered in France in the regions of Montelimar, Nant and Villeneuve-de-Berg. A general public outcry has led the government to freeze the projects till a complete assessment of the impact on the environment is made. The fears of the public are based on the feedback experience in the Usa where some underground waters were polluted. The source of pollution is twofold: first the additives used in the injected fluids (methanol as an anti-microbic agent, hydrochloric acid to dissolve natural cements or glycol ethylene as a deposit inhibitor) and secondly metal particles of copper, zinc or lead trapped in the clay layers and released by the injection of the fluids. It appears also that the injection of high pressure fluids near a crack can induce earth tremors by reactivating the crack. (A.C.)

  12. The Resurgence of Shale Oil

    International Nuclear Information System (INIS)

    Cornot-Gandolphe, Sylvie

    2017-09-01

    This study addresses the resilience factors of the American production of light tight oil, in particular regarding the evolution of the financial model, and the regulatory changes with the authorisation of exports for crude oil. The paper also evaluates the development perspectives of the production on the medium and long term. US production of light tight oil (LTO, commonly known as 'shale oil') experienced a spectacular expansion between 2010 and 2014, becoming the largest source of growth in world oil production. At the start of 2015, however, the sustainability of its business model became questionable. Oil prices had collapsed and uncertainty about future US production was at its height. The sharp drop in the number of drill holes as of January 2015 raised fears of a rapid fall in US petroleum output. The LTO business model, based largely on the use of debt, reinforced this projection. Independent producers were heavily indebted, and were no longer able to invest in new wells. LTO production would therefore run out of steam. Two years later, LTO has passed its first test successfully. While output of shale gas has clearly fallen, cuts have been modest and much less than had been feared, given the falls in capital spending (CAPEX) and the number of drill holes. Productivity improvements as well as cost reductions have permitted a halving of the LTO equilibrium price. Independent producers have refocused their activities on the most productive basins and sites. The essential role played by the Permian Basin should be stressed at this point. In two years, it has become a new El dorado. Despite the fall in drill holes through to May 2016, production has continued to rise and now amounts to a quarter of American oil output. Furthermore, independents have drawn extra value from their well inventories, which include drilled, but also uncompleted wells. Lastly, the impressive number of drilled wells prior to price cuts has allowed producers to maintain their output

  13. EVALUATION OF SHALE GAS POTENTIAL IN KAZAKHSTAN

    Directory of Open Access Journals (Sweden)

    Lidiya Parkhomchik

    2015-01-01

    Full Text Available The article considers the primary evaluation of the shale gas resource potential in Kazakhstan, as well as defines the most problematic issues for the large-scale shale gas production over the state. The authors pay special attention to the national strategy of the Kazakhstani government in the sphere of the unconventional energy sources production, defining the possible technological and environmental problems for the shale gas extraction. The article also notes that implementation of the fracking technologies in the country could cause both positive and negative effects on the economy of Kazakhstan. Therefore, further steps in this direction should be based on the meaningful and comprehensive geological data regarding the shale gas potential.

  14. Process for desulfurizing shale oil, etc

    Energy Technology Data Exchange (ETDEWEB)

    Escherich, F

    1922-12-17

    A process is described for the desulfurizing of shale oil or tar, with recovery of valuable oils and hydrocarbons, characterized in that the raw material is heated in an autoclave to a pressure of 100 atmospheres or more.

  15. Texture and anisotropy analysis of Qusaiba shales

    KAUST Repository

    Kanitpanyacharoen, Waruntorn; Wenk, Hans-Rudolf; Kets, Frans; Lehr, Christian; Wirth, Richard

    2011-01-01

    Scanning and transmission electron microscopy, synchrotron X-ray diffraction, microtomography and ultrasonic velocity measurements were used to characterize microstructures and anisotropy of three deeply buried Qusaiba shales from the Rub

  16. Fourier Transform Infrared Spectroscopic Determination of Shale ...

    African Journals Online (AJOL)

    acer

    minerals in the mixtures. Samples from a suite of shale reservoir rocks were analysed using standard .... qualitatative and quantitative analysis of soil properties. For example a .... using Cobalt Ka radiation range. Samples were analysed in ...

  17. Triterpene alcohol isolation from oil shale.

    Science.gov (United States)

    Albrecht, P; Ourisson, G

    1969-03-14

    Isoarborinol, an intact pentacyclic unsaturated alcohol, was isolated from the Messel oil shale (about 50 x 106 years old). Complex organic substances, even those very sensitive to oxidation, reduction, or acidic conditions, can thus survive without alteration for long periods.

  18. The Jurassic of Denmark and Greenland: key elements in the reconstruction of the North Atlantic Jurassic rift system

    Directory of Open Access Journals (Sweden)

    Surlyk, Finn

    2003-10-01

    Full Text Available The Jurassic succession of Denmark is largely confined to the subsurface with the exception of exposures on the island of Bornholm in the Baltic Sea. In East Greenland, in contrast, the Jurassic is extensively exposed. Comparison of basin evolution in the two regions, which now occur on two separate plates, thus relies on highly different datasets. It is possible nevertheless to construct an integrated picture allowing testing of hypotheses concerning basin evolution, regional uplift, onset and climax of rifting, relative versus eustatic sea-level changes and sequence stratigraphic subdivision and correlation. On a smaller scale, it is possible to compare the signatures of sequence stratigraphic surfaces as seen on well logs, in cores and at outcrop and of sequences recognised and defined on the basis of very different data types. Breakdown of the successions into tectonostratigraphic megasequences highlights the high degree of similarity in overall basin evolution and tectonic style. An important difference, however, lies in the timing. Major events such as late Early - Middle Jurassic uplift, followed by onset of rifting, basin reorganisation and rift climax were delayed in East Greenland relative to the Danish region. This has important implications both for regional reconstructions of the rift system and for the understanding and testing of classical sequence stratigraphic concepts involving eustatic versus tectonic controls of basin evolution and stratigraphy.

  19. Legal Regime of Shale Gas Extraction

    OpenAIRE

    Ovidiu – Horia Maican

    2013-01-01

    Some countries with large reserves intend to promote shale gas production, in order to reduce their dependency on imported gas. Shale gas will be an important new aspect in the world energy scene, with many effects. European Union wants secure and affordable sources of energy. Natural gas is the cleanest fossil fuel and a vital component of European Union's energy strategy. One of the most important aspects is that gas produces significantly cleaner energy than other fossil fuels. From a lega...

  20. The influence of shale gas on steamcracking

    Energy Technology Data Exchange (ETDEWEB)

    Rupieper, A. [Linde Engineering Dresden GmbH, Dresden (Germany)

    2013-11-01

    US shale gas reserves with more than 860 TCF (Source: U.S. Energy Information Administration study World Shale Gas Resources) account for 2 of the global largest reserves after China. In 7 areas of the US, these reserves are systematically explored, providing a significant amount of cheap natural gas source for decades. The ethane share, carried by such shale gas, can reach up to 16%. Ethane has been already in the past 2 most important feedstock for Steamcrackers, being the backbone of the Petrochemical Industry. Due to availability of vast shale gas, the US steamcracker industry is facing a shift from naphtha to shale gas ethane, as the margin of Ethylene produced from shale gas ethane is significantly larger than that of naphtha based Ethylene (app. + 630 USD/t Ethylene). As a consequence shale gas is ''the magic bullet'' incinerating investments into Steamcrackers and downstream plants for U.S petrochemical industry. Steamcracker Projects with an additional ethylene production capacity of more than 17 million tons/a by 2020 are announced or already under construction. Investments into downstream plants refining the C2 derivatives will follow or are already in planning/engineering phase. But the US market cannot absorb all related products, causing a significant export exposure, which will influence global trade flows for C2 derivatives and affect prices. This article presents the impact of shale gas ethane cracking on: - Trade flow of C2 derivatives; - By-product deficits; - Alternate C3+ derivative production routes; - Challenges related to engineering requirements and project execution for Steamcracker projects. (orig.)

  1. Along strike behavior of the Tizi n' Firest fault during the Lower Jurassic rifting (Central High Atlas Carbonate basin, Morocco)

    Science.gov (United States)

    Sarih, S.; Quiquerez, A.; Allemand, P.; Garcia, J. P.; El Hariri, K.

    2018-03-01

    The purpose of this study is to document the along-strike early syn-rift history of the Lower Jurassic Carbonate basin of the Central High Atlas (Morocco) by combining sedimentological observations and high-resolution biostratigraphy. Six sections, each from the Sinemurian to the Upper Pliensbachian, were investigated along a 75 km-long transect at the hanging wall of a major fault of the Lower Jurassic Basin (i.e. the Tizi n' Firest fault). Depositional geometries of the early syn-rift deposits were reconstructed from the correlation between eight main timelines dated by biochronological markers for a time span covering about 6 Ma. Depocentre migration was examined and accommodation rates were calculated at the sub-zone timescale to discuss the along-strike-fault behavior of the Lower Jurassic basin formation. The early stages of extension are marked by contrasted along-strike variations in depositional geometry thickness, depocentre migration and accommodation rates, leading to the growth of three independent sub-basins (i.e. western, central, and eastern), ranging in size from 30 to 50 km, and displaying three contrasted tectono-sedimentary histories. Our results suggest that, during the early rifting phase, tectonic activity was not a continuous and progressive process evolving towards a rift climax stage, but rather a series of acceleration periods that alternated with periods of much reduced activity. The length of active fault segments is estimated at about 15-20 km, with a lifespan of a few ammonite sub-zones (> 2-3 Ma).

  2. Oil shale mines and their realizable production

    International Nuclear Information System (INIS)

    Habicht, K.

    1994-01-01

    The production of Estonian oil shale depends on its marketing opportunities. The realizable production is a function of the oil shale price, which in turn depends on production costs. The latter are dependent on which mines are producing oil shale and on the volume of production. The purpose of the present article is to analyze which mines should operate under various realizable production scenarios and what should be their annual output so that the total cost of oil shale production (including maintenance at idle mines) is minimized. This paper is also targeted at observing the change in the average production cost per ton of oil shale depending on the realizable output. The calculations are based on data for the first four months of 1993, as collected by N. Barabaner (Estonian Academy of Sciences, Institute of Economy). The data include the total production volume and production cost from the mines of RE 'Eesti Polevkivi' (State Enterprise 'Estonian Oil Shale'). They also project expenses from mine closings in case of conservation. The latter costs were allocated among mines in direct proportion to their respective number of employees. (author)

  3. Senate hearings whet interest in oil shale

    Energy Technology Data Exchange (ETDEWEB)

    Remirez, R

    1967-06-05

    Recent oil shale hearings by the U.S. Senate disclosed the proposed leasing rules for federal oil-shale lands. In addition, Oil Shale Corp. announced that the first commercial shale-oil processing plant would be on stream in 1970. Both these announcements are expected to create a stronger interest in what is possibly the greatest untapped natural wealth in the U.S. According to the leasing rules, development leases would involve the following phases: (1) the contractor would have a 10-yr limit to conduct a research and development program on the leased territory; and (2) upon completion of a successful research program, the Interior Department will make available to lease at least enough land to sustain commercial operation. The terms that applicants will have to meet are included in this report. At the Senate hearing, discussions ranged from opinions indicating that development of oil shale recovery was not immediately necessary to opinions urging rapid development. This report is concluded with a state-of-the-art review of some of the oil shale recovery processes.

  4. Environmental control costs for oil shale processes

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-10-01

    The studies reported herein are intended to provide more certainty regarding estimates of the costs of controlling environmental residuals from oil shale technologies being readied for commercial application. The need for this study was evident from earlier work conducted by the Office of Environment for the Department of Energy Oil Shale Commercialization Planning, Environmental Readiness Assessment in mid-1978. At that time there was little reliable information on the costs for controlling residuals and for safe handling of wastes from oil shale processes. The uncertainties in estimating costs of complying with yet-to-be-defined environmental standards and regulations for oil shale facilities are a critical element that will affect the decision on proceeding with shale oil production. Until the regulatory requirements are fully clarified and processes and controls are investigated and tested in units of larger size, it will not be possible to provide definitive answers to the cost question. Thus, the objective of this work was to establish ranges of possible control costs per barrel of shale oil produced, reflecting various regulatory, technical, and financing assumptions. Two separate reports make up the bulk of this document. One report, prepared by the Denver Research Institute, is a relatively rigorous engineering treatment of the subject, based on regulatory assumptions and technical judgements as to best available control technologies and practices. The other report examines the incremental cost effect of more conservative technical and financing alternatives. An overview section is included that synthesizes the products of the separate studies and addresses two variations to the assumptions.

  5. Depositional features of the Middle Jurassic formation of Field N and their influence on optimal drilling schedule

    International Nuclear Information System (INIS)

    Mishina, D; Rukavishnikov, V; Belozerov, B; Bochkov, A

    2015-01-01

    The Middle Jurassic formation of Field N represented by 4 hydrodynamically connected layers (J5-6, J4, J3 and J2) contains 42% of the field STOIIP. The J2-6 formation is characterized as a gas-oil-condensate massive lithologically and tectonically screened accumulation with a gas cap (J2, J3 layers) and bottom water (J5-6 layer). Oil is predominantly in the J3 and J4 layers. There is a high risk of early gas coning from gas-bearing layers to oil producing wells determined on the basis of production test results, which can significantly decrease the life of the well. To select a more optimal drilling schedule, it is necessary to take the risk of early gas coning into account and determine distinctive features within the gas- saturated zone that can reduce it. The presence of a thick shale barrier between the J2 and J3 layers with thicknesses varying from 0 to 30 m is recognized as the beginning of a transgression cycle, and if the gas cap is only in the J2 layer, this barrier with the thickness of more than 5 m can extensively prevent early gas coning into oil producing wells. The integration of geological information represented by the probability map constructed and petrophysical information represented by the kh map provide the more precise determination of an optimal drilling schedule

  6. Thermochronological Record of a Jurassic Heating-Cooling Cycle Within a Distal Rifted Margin (Calizzano Massif, Ligurian Alps)

    Science.gov (United States)

    Seno, S.; Decarlis, A.; Fellin, M. G.; Maino, M.; Beltrando, M.; Ferrando, S.; Manatschal, G.; Gaggero, L.; Stuart, F. M.

    2017-12-01

    The aim of the present study is to analyse, through thermochronological investigations, the thermal evolution of a fossil distal margin owing to the Alpine Tethys rifting system. The studied distal margin section consists of a polymetamorphic basement (Calizzano basement) and of a well-developed Mesozoic sedimentary cover (Case Tuberto unit) of the Ligurian Alps (NW Italy). The incomplete reset of zircon (U-Th)/He ages and the non-reset of the zircon fission track ages during the Alpine metamorphism indicate that during the subduction and the orogenic stages these rocks were subjected to temperatures lower than 200 ºC. Thus, the Alpine metamorphic overprint occurred during a short-lived, low temperature pulse. The lack of a pervasive orogenic reset, allowed the preservation of an older heating-cooling event that occurred during Alpine Tethys rifting. Zircon fission-track data indicate, in fact, that the Calizzano basement records a cooling under 240 °C, at 156 Ma (early Upper Jurassic). This cooling followed a Middle Jurassic syn-rift heating at temperatures of about 300-350°C, typical of greenschist facies conditions occurred at few kilometres depth, as indicated by stratigraphic and petrologic constraints. Thus, in our interpretation, major crustal thinning likely promoted high geothermal gradients ( 60-90°C/km) triggering the circulation of hot, deep-seated fluids along brittle faults, causing the observed thermal anomaly at shallow crustal level.

  7. Gasification of oil shale by solar energy

    International Nuclear Information System (INIS)

    Ingel, Gil

    1992-04-01

    Gasification of oil shales followed by catalytic reforming can yield synthetic gas, which is easily transportable and may be used as a heat source or for producing liquid fuels. The aim of the present work was to study the gasification of oil shales by solar radiation, as a mean of combining these two energy resources. Such a combination results in maximizing the extractable fuel from the shale, as well as enabling us to store solar energy in a chemical bond. In this research special attention was focused upon the question of the possible enhancement of the gasification by direct solar irradiation of the solid carbonaceous feed stock. The oil shale served here as a model feedstock foe other resources such as coal, heavy fuels or biomass all of which can be gasified in the same manner. The experiments were performed at the Weizman institute's solar central receiver, using solar concentrated flux as an energy source for the gasification. The original contributions of this work are : 1) Experimental evidence is presented that concentrated sunlight can be used effectively to carry out highly endothermic chemical reactions in solid particles, which in turn forms an essential element in the open-loop solar chemical heat pipe; 2) The solar-driven gasification of oil shales can be executed with good conversion efficiencies, as well as high synthesis gas yields; 3)There was found substantial increase in deliverable energy compared to the conventional retorting of oil shales, and considerable reduction in the resulting spent shale. 5) A detailed computer model that incorporates all the principal optical and thermal components of the solar concentrator and the chemical reactor has been developed and compared favorably against experimental data. (author)

  8. Using Neutron Scattering and Mercury Intrusion Techniques to Characterize Micro- and Nano-Pore Structure of Shale

    Science.gov (United States)

    Zhang, Y.; Barber, T.; Hu, Q.; Bleuel, M.

    2017-12-01

    The micro- and nano-pore structure of oil shale plays a critical role in hydrocarbon storage and migration. This study aims to characterize the pore structure of three Bakken members (i.e., upper organic-rich shale, middle silty/sandy dolomites, and lower organic-rich shale), through small and ultra-small angle neutron scattering (SANS and USANS) techniques, as well as mercury injection capillary pressure (MICP) analyses. SANS/USANS have the capabilities of measuring total porosity (connected and closed porosity) across nm-mm spectrum, not measurable than other fluid-invasion approaches, such as MICP which obtains connected porosity and pore-throat size distribution. Results from both techniques exhibit different features of upper/lower Bakken and middle Bakken, as a result of various mineral composition and organic matter contents. Middle Bakken is primarily dominated by the mineral pores, while in the upper and lower Bakken, organic pores contribute a significant portion of total porosity. A combination of USANS/SANS and MICP techniques gives a comprehensive picture of shale micro- and nano-pore structure.

  9. Experimental Study of Cement - Sandstone/Shale - Brine - CO2 Interactions.

    Science.gov (United States)

    Carroll, Susan A; McNab, Walt W; Torres, Sharon C

    2011-11-11

    Reactive-transport simulation is a tool that is being used to estimate long-term trapping of CO2, and wellbore and cap rock integrity for geologic CO2 storage. We reacted end member components of a heterolithic sandstone and shale unit that forms the upper section of the In Salah Gas Project carbon storage reservoir in Krechba, Algeria with supercritical CO2, brine, and with/without cement at reservoir conditions to develop experimentally constrained geochemical models for use in reactive transport simulations. We observe marked changes in solution composition when CO2 reacted with cement, sandstone, and shale components at reservoir conditions. The geochemical model for the reaction of sandstone and shale with CO2 and brine is a simple one in which albite, chlorite, illite and carbonate minerals partially dissolve and boehmite, smectite, and amorphous silica precipitate. The geochemical model for the wellbore environment is also fairly simple, in which alkaline cements and rock react with CO2-rich brines to form an Fe containing calcite, amorphous silica, smectite and boehmite or amorphous Al(OH)3. Our research shows that relatively simple geochemical models can describe the dominant reactions that are likely to occur when CO2 is stored in deep saline aquifers sealed with overlying shale cap rocks, as well as the dominant reactions for cement carbonation at the wellbore interface.

  10. Distribution of K, Na, Th and U in sandstones and shales from western Shikoku, Japan

    International Nuclear Information System (INIS)

    Ishihara, Shunso; Sakamaki, Yukio; Mochizuki, Tsunekazu; Terashima, Shigeru; Endo, Yuji

    1981-01-01

    The regional variation of K, Na, Th and U distributions was studied on 58 sandstones, 81 shales and 3 green schists from the sedimentary terrains across western Shikoku. The geological structure of the studied district is explained. The regional characteristics of the sedimentary rocks are best demonstrated in the composition of the sandstones. The sandstones, in the source areas of which granitic and rhyolitic rocks exist and which have been deposited rapidly, were rich in K, whereas those derived mainly from mafic volcanic areas showed high Na content. The sandstones of the Shimanto Supergroup had the intermediate values, and K and K + Na contents became low in the south where the younger Upper Shimanto Group is exposed. Th and U in both sandstones and shales were highest in the Izumi Group, and generally low in the Shimanto Supergroup. The black shales of the Shimanto Supergroup did not show U-anomaly. In each group, highly matured rocks gave slightly higher Th/U ratio. Highly matured polycyclic sediments contained the least amount of radioactive elements. The radioactive anomaly due to the anomalous K contained in sericite, and that due to U in black shale were found in Chichibu and Sambosan belts. Similar anomaly was discovered in the foot wall of Mn deposits in the same zone. The possibility of anomalous U may be the least in the Shimanto Supergroup. (Kako, I.)

  11. Tectonic forcing of early to middle jurassic seawater Sr/Ca

    DEFF Research Database (Denmark)

    Ullmann, Clemens Vinzenz; Hesselbo, Stephen P.; Korte, Christoph

    2013-01-01

    The Jurassic Period (ca. 201–145 Ma) is marked by fundamental reorganizations of paleogeography, paleoceanography, ecosystems, and the progressive shift from aragonite to calcite as the favored marine biogenic carbonate polymorph. Sr/Ca ratios of well-preserved Jurassic oysters and belemnites from...

  12. Evidence of lacustrine sedimentation in the Upper Permian Bijori

    Indian Academy of Sciences (India)

    The Upper Permian Bijori Formation of the Satpura Gondwana basin comprising fine- to coarsegrained sandstone, carbonaceous shale/mudstone and thin coal bands was previously interpreted as the deposits of meandering rivers. The present study documents abundance of wave ripples, hummocky and swaley ...

  13. Iron speciation and mineral characterization of upper Jurassic reservoir rocks in the Minhe Basin, NW China

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Xiangxian; Zheng, Guodong, E-mail: gdzhbj@mail.iggcas.ac.cn; Xu, Wang [Chinese Academy of Sciences, Key Laboratory of Petroleum Resources, Gansu Province / Key Laboratory of Petroleum Resources Research, Institute of Geology and Geophysics (China); Liang, Minliang [Chinese Academy of Geological Sciences, Institute of Geomechanics, Key Lab of Shale Oil and Gas Geological Survey (China); Fan, Qiaohui; Wu, Yingzhong; Ye, Conglin [Chinese Academy of Sciences, Key Laboratory of Petroleum Resources, Gansu Province / Key Laboratory of Petroleum Resources Research, Institute of Geology and Geophysics (China); Shozugawa, Katsumi; Matsuo, Motoyuki [The University of Tokyo, Graduate School of Arts and Sciences (Japan)

    2016-12-15

    Six samples from a natural outcrop of reservoir rocks with oil seepage and two control samples from surrounding area in the Minhe Basin, northwestern China were selectively collected and analyzed for mineralogical composition as well as iron speciation using X-ray powder diffraction (XRD) and Mössbauer spectroscopy, respectively. Iron species revealed that: (1) the oil-bearing reservoir rocks were changed by water-rock-oil interactions; (2) even in the same site, there was a different performance between sandstone and mudstone during the oil and gas infusion to the reservoirs; and (3) this was evidence indicating the selective channels of hydrocarbon migration. In addition, these studies showed that the iron speciation by Mössbauer spectroscopy could be useful for the study of oil and gas reservoirs, especially the processes of the water-rock interactions within petroleum reservoirs.

  14. Characterization of nanoporous shales with gas sorption

    Science.gov (United States)

    Joewondo, N.; Prasad, M.

    2017-12-01

    The understanding of the fluid flow in porous media requires the knowledge of the pore system involved. Fluid flow in fine grained shales falls under different regime than transport regime in conventional reservoir due to the different average pore sizes in the two materials; the average pore diameter of conventional sandstones is on the micrometer scale, while of shales can be as small as several nanometers. Mercury intrusion porosimetry is normally used to characterize the pores of conventional reservoir, however with increasingly small pores, the injection pressure required to imbibe the pores becomes infinitely large due to surface tension. Characterization of pores can be expressed by a pore size distribution (PSD) plot, which reflects distribution of pore volume or surface area with respect to pore size. For the case of nanoporous materials, the surface area, which serves as the interface between the rock matrix and fluid, becomes increasingly large and important. Physisorption of gas has been extensively studied as a method of nanoporous solid characterization (particularly for the application of catalysis, metal organic frameworks, etc). The PSD is obtained by matching the experimental result to the calculated theoretical result (using Density Functional Theory (DFT), a quantum mechanics based modelling method for molecular scale interactions). We present the challenges and experimental result of Nitrogen and CO2 gas sorption on shales with various mineralogy and the interpreted PSD obtained by DFT method. Our result shows significant surface area contributed by the nanopores of shales, hence the importance of surface area measurements for the characterization of shales.

  15. A New Insight into Shale-Gas Accumulation Conditions and Favorable Areas of the Xinkailing Formation in the Wuning Area, North-West Jiangxi, China

    Directory of Open Access Journals (Sweden)

    Shangru Li

    2017-12-01

    Full Text Available In north-west Jiangxi, China, most shale-gas exploration has been focused on the Lower Cambrian Hetang and Guanyintang formations, whereas the Upper Ordovician Xinkailing formation shale has been ignored for years due to heavy weathering. This study systematically analyzed gas source conditions, reservoir conditions and gas-bearing ability in order to reveal the shale-gas accumulation conditions of the Xinkailing formation. The results show that the Xinkailing formation is characterized by thick deposition of black shale (10–80 m, high organic content (with total organic carbon between 1.18% and 3.11%, on average greater than 2%, relatively moderate thermal evolution (with vitrinite reflectance between 2.83% and 3.21%, high brittle-mineral content (greater than 40%, abundant nanopores and micro-fractures, very good adsorption ability (adsorption content between 2.12 m3/t and 3.47 m3/t, on average about 2.50 m3/t, and strong sealing ability in the underlying and overlying layers, all of which favor the generation and accumulation of shale gas. The Wuning-Lixi and Jinkou-Zhelin areas of the Xinkailing formation were selected as the most realistic and favorable targets for shale-gas exploration and exploitation. In conclusion, the Wuning area has great potential and can provide a breakthrough in shale gas with further investigation.

  16. Characterisation of organic carbon in black shales of the Kachchh ...

    Indian Academy of Sciences (India)

    46

    2Petroleum Geochemistry and Microbiology Group, National Geophysical Research Institute, .... gypsiferous shale of the Naredi Formation of early Eocene age (Biswas 1992). The shale .... This inference also helps us to explain the existence.

  17. A re-examination of paleomagnetic results from NA Jurassic sedimentary rocks: Additional evidence for proposed Jurassic MUTO?

    Science.gov (United States)

    Housen, B. A.

    2015-12-01

    Kent and Irving, 2010; and Kent et al, 2015 propose a monster shift in the position of Jurassic (160 to 145 Ma) paleopoles for North America- defined by results from igneous rocks. This monster shift is likely an unrecognized true polar wander occurrence. Although subject to inclination error, results from sedimentary rocks from North America, if corrected for these effects, can be used to supplement the available data for this time period. Steiner (2003) reported results from 48 stratigraphic horizons sampled from the Callovian Summerville Fm, from NE New Mexico. A recalculated mean of these results yields a mean direction of D = 332, I = 39, n=48, k = 15, α95 = 5.4°. These data were analyzed for possible inclination error-although the dataset is small, the E-I results yielded a corrected I = 53. This yields a corrected paleopole for NA at ~165 Ma located at 67° N and 168° E.Paleomagnetic results from the Black Hills- Kilanowski (2002) for the Callovian Hulett Mbr of the Sundance Fm, and Gregiore (2001) the Oxfordian-Tithonian Morrison Fm (Gregiore, 2001) have previously been interpreted to represent Eocene-aged remagnetizations- due to the nearly exact coincidence between the in-situ pole positions of these Jurassic units with the Eocene pole for NA. Both of the tilt-corrected results for these units have high latitude poles (Sundance Fm: 79° N, 146° E; Morrison Fm: 89° N, 165° E). An E-I analysis of these data will be presented- using a provisional inclination error of 10°, corrected paleopoles are: (Sundance Fm: 76° N, 220° E; Morrison Fm: 77° N, 266° E). The Black Hills 165 Ma (Sundance Fm) and 145 Ma (Morrison Fm) poles, provisionally corrected for 10° inclination error- occur fairly close to the NA APWP proposed by Kent et al, 2015- using an updated set of results from kimberlites- the agreement between the Sundance Fm and the Triple-B (158 Ma) pole would be nearly exact with a slightly lesser inclination error. The Summerville Fm- which is

  18. Amphibious flies and paedomorphism in the Jurassic period.

    Science.gov (United States)

    Huang, Diying; Nel, André; Cai, Chenyang; Lin, Qibin; Engel, Michael S

    2013-03-07

    The species of the Strashilidae (strashilids) have been the most perplexing of fossil insects from the Jurassic period of Russia and China. They have been widely considered to be ectoparasites of pterosaurs or feathered dinosaurs, based on the putative presence of piercing and sucking mouthparts and hind tibio-basitarsal pincers purportedly used to fix onto the host's hairs or feathers. Both the supposed host and parasite occur in the Daohugou beds from the Middle Jurassic epoch of China (approximately 165 million years ago). Here we analyse the morphology of strashilids from the Daohugou beds, and reach markedly different conclusions; namely that strashilids are highly specialized flies (Diptera) bearing large membranous wings, with substantial sexual dimorphism of the hind legs and abdominal extensions. The idea that they belong to an extinct order is unsupported, and the lineage can be placed within the true flies. In terms of major morphological and inferred behavioural features, strashilids resemble the recent (extant) and relict members of the aquatic fly family Nymphomyiidae. Their ontogeny are distinguished by the persistence in adult males of larval abdominal respiratory gills, representing a unique case of paedomorphism among endopterygote insects. Adult strashilids were probably aquatic or amphibious, shedding their wings after emergence and mating in the water.

  19. Improving horizontal completions on heterogeneous tight shales

    Energy Technology Data Exchange (ETDEWEB)

    Suarez-Rivera, Roberto; Deenadayalu, Chaitanya; Chertov, Maxim; Novalo Hartanto, Ricardo; Gathogo, Patrick [Schlumberger (United States); Kunjir, Rahul [University of Utah (United States)

    2011-07-01

    Evaluation of the two formation characteristics conducive to economic well production is important when tight shale formation characterization and completion design are being considered. This paper presents the basic understanding required to improve the efficiency of horizontal completions in oil and gas producing shales. Guidelines are defined for effective perforation and fracturing to improve the efficiency and sustainability of horizontal completions using extensive laboratory characterization of mechanical properties on core, core/log integration and continuous mapping of these properties by logging-while-drilling (LWD) methods. The objective is to improve completion design efficiency. This is accomplished by suitable selection of perforation intervals based on an understanding of the relevant physical processes and rock characterization. Conditions at two reservoir regions, the near-wellbore and the far-wellbore, are outlined and are essential to completion design. From the study, it can be concluded that tight shales are strongly anisotropic and cannot be approximated using isotropic models.

  20. Cracking mechanism of shale cracks during fracturing

    Science.gov (United States)

    Zhao, X. J.; Zhan, Q.; Fan, H.; Zhao, H. B.; An, F. J.

    2018-06-01

    In this paper, we set up a model for calculating the shale fracture pressure on the basis of Huang’s model by the theory of elastic-plastic mechanics, rock mechanics and the application of the maximum tensile stress criterion, which takes into account such factors as the crustal stress field, chemical field, temperature field, tectonic stress field, the porosity of shale and seepage of drilling fluid and so on. Combined with the experimental data of field fracturing and the experimental results of three axis compression of shale core with different water contents, the results show that the error between the present study and the measured value is 3.85%, so the present study can provide technical support for drilling engineering.

  1. Thermocatalytical processing of coal and shales

    Directory of Open Access Journals (Sweden)

    Zhaksyntay Kairbekov

    2012-12-01

    Full Text Available The article investigates the questions of thermocatalytical conversion of organic mass of coal (OMC, it is shown that in the absence of a catalyst process is carried out by a radical process. Accumulated data on the properties for radicals of different structure and therefore different reaction capacity enables us to understand and interpret the conversion of OMC. Thermal conversion of OMC regarded as a kind of depolymerization, accompanied by decomposition of the functional groups with the formation of radicals, competing for hydrogen atom. Catalyst can change the direction and conditions of the process. Modern catalysts can reduce the process pressure up to 50 atm., with a high degree of coal conversion. We consider examples of simultaneous conversion of coal and shale, shale and masut, shale and tar.

  2. Multiphysical Testing of Soils and Shales

    CERN Document Server

    Ferrari, Alessio

    2013-01-01

    Significant advancements in the experimental analysis of soils and shales have been achieved during the last few decades. Outstanding progress in the field has led to the theoretical development of geomechanical theories and important engineering applications. This book provides the reader with an overview of recent advances in a variety of advanced experimental techniques and results for the analysis of the behaviour of geomaterials under multiphysical testing conditions. Modern trends in experimental geomechanics for soils and shales are discussed, including testing materials in variably saturated conditions, non-isothermal experiments, micro-scale investigations and image analysis techniques. Six theme papers from leading researchers in experimental geomechanics are also included. This book is intended for postgraduate students, researchers and practitioners in fields where multiphysical testing of soils and shales plays a fundamental role, such as unsaturated soil and rock mechanics, petroleum engineering...

  3. Relations globales entre sédimentation de black shales océaniques et dépôts subséquents de phosphates. L'exemple du Crétacé moyen-supérieur de l'Atlantique centre et nord et du Crétacé supérieur-Eocène de la bordure ouest et nord du bouclier Africano-arabe Global Relations Between the Sedimentation of Oceanic Black Shales and Subsequent Phosphate Deposits. Example of the Middle-Upper Cretaceous in the Central and Northern Atlantic and of the Upper Cretaceous-Eocene on the Western and Northern Edges of the African-Arabian Shield

    Directory of Open Access Journals (Sweden)

    Busson G.

    2006-11-01

    contrepartie en phosphore. Les deux phénomènes apparaissent parfaitement complémentaires et ils s'éclairent mutuellement : le phosphore aurait été capitalisé dans les mers à black shales euxiniques de l'Atlantique; puis, lors de l'établissement des premières circulations, il aurait été recyclé sur les plates-formes épicontinentales bordant l'est de cet océan. La discussion porte sur l'ajustement chronologique des deux phénomènes et sur l'interprétation des phosphates téthysiens (Europe, Proche-Orient, etc. dans la perspective des mécanismes proposés. Loin des explications unifactorielles, on souligne la conjonction de facteurs responsables de ce phénomène phosphaté ainsi que de son âge et de ses modalités d'expression. On a global scale, the large-scale accumulations of sedimentary phosphorites seem to be irregularly distributed in time. The ones from the Upper Cretaceous- Eocene on the western and northern edges of the African-Arabian shield are quantitatively exceptional and are interesting because of the ideas they suggest as to a global mechanism. First of all, some present-day oceanographic data are emphasized - movement of phosphate-containing material towards and inside the ocean, distribution of phosphates in oceanic water masses and especially in euxinic waters. The several theories formely proposed to explain the episodic nature of phosphate sedimentation are reviewed and criticized (Strakhov, Fischer, Arthur, Sheldon, etc. . Then the breakdown by countries of the amounts of phosphates deposited in part of the Mesogean and Atlantic realms is given. This causes us to focus our attention on the Moroccan phosphates which are by far the most abundant and are situated in a key position. Nevertheless, it is recalled that the dual latitudinal evolution in the Cretaceous and Paleogene, from the north towards the south in the present northern hemisphere, and from the south towards the north in the present southern hemisphere, makes purely latitudinal

  4. Assessment of potential unconventional lacustrine shale-oil and shale-gas resources, Phitsanulok Basin, Thailand, 2014

    Science.gov (United States)

    Schenk, Christopher J.; Charpentier, Ronald R.; Klett, Timothy R.; Mercier, Tracey J.; Tennyson, Marilyn E.; Pitman, Janet K.; Brownfield, Michael E.

    2014-01-01

    Using a geology-based assessment methodology, the U.S. Geological Survey assessed potential technically recoverable mean resources of 53 million barrels of shale oil and 320 billion cubic feet of shale gas in the Phitsanulok Basin, onshore Thailand.

  5. Thermal effects in shales: measurements and modeling

    International Nuclear Information System (INIS)

    McKinstry, H.A.

    1977-01-01

    Research is reported concerning thermal and physical measurements and theoretical modeling relevant to the storage of radioactive wastes in a shale. Reference thermal conductivity measurements are made at atmospheric pressure in a commercial apparatus; and equipment for permeability measurements has been developed, and is being extended with respect to measurement ranges. Thermal properties of shales are being determined as a function of temperature and pressures. Apparatus was developed to measure shales in two different experimental configurations. In the first, a disk 15 mm in diameter of the material is measured by a steady state technique using a reference material to measure the heat flow within the system. The sample is sandwiched between two disks of a reference material (single crystal quartz is being used initially as reference material). The heat flow is determined twice in order to determine that steady state conditions prevail; the temperature drop over the two references is measured. When these indicate an equal heat flow, the thermal conductivity of the sample can be calculated from the temperature difference of the two faces. The second technique is for determining effect of temperature in a water saturated shale on a larger scale. Cylindrical shale (or siltstone) specimens that are being studied (large for a laboratory sample) are to be heated electrically at the center, contained in a pressure vessel that will maintain a fixed water pressure around it. The temperature is monitored at many points within the shale sample. The sample dimensions are 25 cm diameter, 20 cm long. A micro computer system has been constructed to monitor 16 thermocouples to record variation of temperature distribution with time

  6. Laboratory weathering of combusted oil shale

    International Nuclear Information System (INIS)

    Essington, M.E.

    1991-01-01

    The objective of this study was to examine the mineralogy and leachate chemistry of three combusted oil shales (two Green River Formation and one New Albany) in a laboratory weathering environment using the humidity cell technique. The mineralogy of the combusted western oil shales (Green River Formation) is process dependent. In general, processing resulted in the formation of anhydrite, lime, periclase, and hematite. During the initial stages of weathering, lime, periclase, and hematite. During the initial stages of weathering, lime, periclase, and anhydrite dissolve and ettringite precipitates. The initial leachates are highly alkaline, saline, and dominated by Na, hydroxide, and SO 4 . As weathering continues, ettringite precipitates. The initial leachates are highly alkaline, saline, and dominated by Na, hydroxide, and SO 4 . As weathering continues, ettringite dissolves, gypsum and calcite precipitate, and the leachates are dominated by Mg, SO 4 , and CO 3 . Leachate pH is rapidly reduced to between 8.5 and 9 with leaching. The combusted eastern oil shale (New Albany) is composed of quartz, illite, hematite, and orthoclase. Weathering results in the precipitation of gypsum. The combusted eastern oil shale did not display a potential to produce acid drainage. Leachate chemistry was dominated by Ca and SO 4 . Element concentrations continually decreased with weathering. IN a western disposal environment receiving minimal atmospheric precipitation, spent oil shale will remain in the initial stages of weathering, and highly alkaline and saline conditions will dominate leachate chemistry. In an eastern disposal environment, soluble salts will be rapidly removed from the spent oil shale to potentially affect the surrounding environment

  7. New Jurassic tettigarctid cicadas from China with a novel example of disruptive coloration

    Directory of Open Access Journals (Sweden)

    Jun Chen

    2016-12-01

    Full Text Available Tettigarctidae is the most primitive family of Cicadoidea, with only two relict species. Although they are relatively well known from Eurasia, Australia, Africa, and South America, their Mesozoic examples are typically preserved only as isolated forewings. Herein, a new genus Sanmai Chen, Zhang, and B. Wang with three new species (Sanmai kongi Chen, Zhang, and B. Wang, S. mengi Chen, Zhang, and B. Wang, and S. xuni Chen, Zhang, and B. Wang are described based on fossil specimens from the Middle–Upper Jurassic of northeastern China, with well-preserved body structures, forewing and hindwing venations, making it the hitherto best known extinct tettigarctid taxon. The new genus, provisionally assigned to the tribe Turutanoviini, provides some new information about the evolution and palaeobiogeography of Mesozoic Tettigarctidae. The genus Paraprosbole is synonymized with Shuraboprosbole. In addition, the coloration pattern of forewing, prominent on some specimens of Sanmai kongi Chen, Zhang, and B. Wang sp. nov. and Sanmai xuni Chen, Zhang, and B. Wang sp. nov., represents a novel example of disruptive coloration in Tettigarctidae, which can effectively break up the body outline as well as surface, and so likely enabled these cicadas to reduce the detectability of potential predators.

  8. Preparing hydraulic cement from oil-shale slag

    Energy Technology Data Exchange (ETDEWEB)

    1921-11-19

    A process for the preparation of hydraulic cementing material from oil shale or oil-shale slag according to Patent 411,584 is characterized by the fact that the oil-shale slag is added to burnt marl, blast-furnace slag, and the like, whereupon the mixture is milled to dust in the known way.

  9. Rapid gas development in the Fayetteville shale basin, Arkansas

    Science.gov (United States)

    Advances in drilling and extraction of natural gas have resulted in rapid expansion of wells in shale basins. The rate of gas well installation in the Fayetteville shale is 774 wells a year since 2005 with thousands more planned. The Fayetteville shale covers 23,000 km2 although ...

  10. Reducing the greenhouse gas footprint of shale gas

    International Nuclear Information System (INIS)

    Wang Jinsheng; Ryan, David; Anthony, Edward J.

    2011-01-01

    Shale gas is viewed by many as a global energy game-changer. However, serious concerns exist that shale gas generates more greenhouse gas emissions than does coal. In this work the related published data are reviewed and a reassessment is made. It is shown that the greenhouse gas effect of shale gas is less than that of coal over long term if the higher power generation efficiency of shale gas is taken into account. In short term, the greenhouse gas effect of shale gas can be lowered to the level of that of coal if methane emissions are kept low using existing technologies. Further reducing the greenhouse gas effect of shale gas by storing CO 2 in depleted shale gas reservoirs is also discussed, with the conclusion that more CO 2 than the equivalent CO 2 emitted by the extracted shale gas could be stored in the reservoirs at significantly reduced cost. - Highlights: ► The long-term greenhouse gas footprint of shale gas is smaller than that of coal. ► Carbon capture and storage should be considered for fossil fuels including shale gas. ► Depleted shale gas fields could store more CO 2 than the equivalent emissions. ► Linking shale gas development with CO 2 storage could largely reduce the total cost.

  11. Extraction of hydrocarbon products from shales and coals

    Energy Technology Data Exchange (ETDEWEB)

    Reed, V Z

    1918-05-17

    A process is disclosed of extracting hydrocarbon oil matter from petroleum-bearing shales and coals which comprises subjecting a mass of such shale or coal, before distillation to the solvent action of material containing an acid, permitting the solvent material to pass through the mass of shale or coal, and recovering the combined solvent and extracted matter.

  12. shales: a review of their classifications, properties and importance to ...

    African Journals Online (AJOL)

    DJFLEX

    In the Niger Delta petroleum province, the source rocks and seal rocks are the marine/deltaic, plastic and over-pressured shales of Akata and Agbada Formations. KEY WORDS: Shales, Classification, Strength, Composition, Petroleum Industry, Niger Delta. INTRODUCTION. Shales are fine-grained laminated or fissile.

  13. Method of concentrating oil shale by flotation

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, M

    1941-01-28

    A method is described of concentrating oil shale by flotation. It is characterized by grinding the shale to a grain size which, roughly speaking, is less than 0.06 mm. and more conveniently should be less than 0.05 mm., and followed by flotation. During the process the brown foam formed is separated as concentrate, while the black-brown to all-black foam is separated as a middle product, ground fine again, and thereafter floated once more. The patent contains five additional claims.

  14. Black shales and naftogenesis. A review

    International Nuclear Information System (INIS)

    Yudovich, Yu.E.; Ketris, M.P.

    1993-01-01

    A genetic relation between petroleum plus hydrocarbon gases and bio organic authigenic matter has been well established. As black shales are enriched in organic matter they may serve as potential petroleum beds on the depths suitable for petroleum generation (2-5 km). The calculations made by petroleum geologists showed that hydrocarbon amounts generated by black shales made up to one fifth of the initial organic matter at the end of MK-2 stage of catagenesis. Consequently, black shales may serve as the main oil producers in many sedimentary basins. Petroleum generation in black shales has some peculiarities. Abundant masses of organic matter generate huge amounts of hydrocarbon gases which in turn produce anomalous high bed pressures followed by pulse cavitation effect. Bed pressures 1.5 times higher than normal lithostatic pressure have been detected in oil-bearing black shales of the Cis-Caucasus on the depth of 2.0-2.5 km, along with very high (6 degrees per 100 m) geothermal gradient. According to Stavropol oil geologists, there occurs an effect of rock-by-fluid-destruction after fluid pressure has greatly exceeded the lithostatic pressure. Stress tensions discharge by impulses and cracks may appear with a rate of 0.3-0.7 of the sound speed. Cavitation of gaseous bubbles is produced by sharp crack extension. Such cavitation accounts for impact waves and increased local pressure and temperature. Such an increase, in turn, fastens petroleum generation and new rock cracking. The effect of over-pressed rocks associated with black shales may serve as a process indicator. That is why the geophysical methods detect enhanced specific gravity and decreased porosity zones in such black shales. Cracks and petroleum accumulation occur on the flanks of such zones of rock-by-fluid-destruction. Some black shales may be petroleum-productive due to enhanced uranium content. There exist ideas about uranium-derived heat or radiolytic effects on the petroleum generation. Such

  15. Analysis of the kerogen of oil shales

    Energy Technology Data Exchange (ETDEWEB)

    Quass, F W; Down, A L

    1939-01-01

    Comments are given on the method developed by F. W. Quass for reducing the amount of mineral matter present in certain coals and oil shales (torbanites). The method consisted of grinding oil shale with water in a porcelain ball mill in the presence of oil. The oil formed a paste with the carbonaceous material, and a greater portion of the mineral matter remained suspended in the water and was separated. Ultimate analyses of the enriched samples indicated that the percent of carbon was higher, the percent of hydrogen and oxygen was lower, and the ratio of carbon to hydrogen and carbon to oxygen increased in the enriched samples.

  16. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    Energy Technology Data Exchange (ETDEWEB)

    Brandon C. Nuttall

    2005-04-26

    Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library were sampled to determine CO{sub 2} and CH{sub 4} adsorption isotherms. Sidewall core samples were acquired to investigate CO{sub 2} displacement of methane. An elemental capture spectroscopy log was acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 14 percent. CO{sub 2} adsorption capacities at 400 psi range from a low of 14 scf/ton in less organic-rich zones to more than 136 scf/ton. There is a direct correlation between measured total organic carbon content and the adsorptive capacity of the shale; CO{sub 2} adsorption capacity increases with increasing organic carbon content. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO{sub 2} in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO{sub 2}, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

  17. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    Energy Technology Data Exchange (ETDEWEB)

    Brandon C. Nuttall

    2005-01-28

    Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library were sampled to determine CO{sub 2} and CH{sub 4} adsorption isotherms. Sidewall core samples were acquired to investigate CO{sub 2} displacement of methane. An elemental capture spectroscopy log was acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 14 percent. CO{sub 2} adsorption capacities at 400 psi range from a low of 14 scf/ton in less organic-rich zones to more than 136 scf/ton. There is a direct correlation between measured total organic carbon content and the adsorptive capacity of the shale; CO{sub 2} adsorption capacity increases with increasing organic carbon content. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO{sub 2} in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO{sub 2}, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

  18. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    Energy Technology Data Exchange (ETDEWEB)

    Brandon C. Nuttall

    2004-08-01

    Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library are being sampled to collect CO{sub 2} adsorption isotherms. Sidewall core samples have been acquired to investigate CO{sub 2} displacement of methane. An elemental capture spectroscopy log has been acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 4.62 percent. CO{sub 2} adsorption capacities at 400 psi range from a low of 19 scf/ton in less organic-rich zones to more than 86 scf/ton in the Lower Huron Member of the shale. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO{sub 2} in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO{sub 2}, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

  19. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    Energy Technology Data Exchange (ETDEWEB)

    Brandon C. Nuttall

    2005-07-29

    Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library were sampled to determine CO{sub 2} and CH{sub 4} adsorption isotherms. Sidewall core samples were acquired to investigate CO{sub 2} displacement of methane. An elemental capture spectroscopy log was acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 14 percent. CO{sub 2} adsorption capacities at 400 psi range from a low of 14 scf/ton in less organic-rich zones to more than 136 scf/ton. There is a direct correlation between measured total organic carbon content and the adsorptive capacity of the shale; CO{sub 2} adsorption capacity increases with increasing organic carbon content. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO{sub 2} in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO{sub 2}, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

  20. Characterization of shale gas enrichment in the Wufeng Formation–Longmaxi Formation in the Sichuan Basin of China and evaluation of its geological construction–transformation evolution sequence

    Directory of Open Access Journals (Sweden)

    Zhiliang He

    2017-02-01

    Full Text Available Shale gas in Upper Ordovician Wufeng Formation–Lower Silurian Longmaxi Formation in the Sichuan Basin is one of the key strata being explored and developed in China, where shale gas reservoirs have been found in Fuling, Weiyuan, Changning and Zhaotong. Characteristics of shale gas enrichment in the formation shown by detailed profiling and analysis are summarized as “high, handsome and rich”. “High” mainly refers to the high quality of original materials for the formation of shale with excellent key parameters, including the good type and high abundance of organic matters, high content of brittle minerals and moderate thermal evolution. “Handsome” means late and weak deformation, favorable deformation mode and structure, and appropriate uplift and current burial depth. “Rich” includes high gas content, high formation pressure coefficient, good reservoir property, favorable reservoir scale transformation and high initial and final output, with relative ease of development and obvious economic benefit. For shale gas enrichment and high yield, it is important that the combination of shale was deposited and formed in excellent conditions (geological construction, and then underwent appropriate tectonic deformation, uplift, and erosion (geological transformation. Evaluation based on geological construction (evolution sequence from formation to the reservoir includes sequence stratigraphy and sediment, hydrocarbon generation and formation of reservoir pores. Based on geological transformation (evolution sequence from the reservoir to preservation, the strata should be evaluated for structural deformation, the formation of reservoir fracture and preservation of shale gas. The evaluation of the “construction - transformation” sequence is to cover the whole process of shale gas formation and preservation. This way, both positive and negative effects of the formation-transformation sequence on shale gas are assessed. The evaluation

  1. Factors controlling Li concentration and isotopic composition in formation waters and host rocks of Marcellus Shale, Appalachian Basin

    Science.gov (United States)

    Phan, Thai T.; Capo, Rosemary C; Stewart, Brian W.; Macpherson, Gwen; Rowan, Elisabeth L.; Hammack, Richard W.

    2015-01-01

    In this study, water and whole rock samples from hydraulically fractured wells in the Marcellus Shale (Middle Devonian), and water from conventional wells producing from Upper Devonian sandstones were analyzed for lithium concentrations and isotope ratios (δ7Li). The distribution of lithium concentrations in different mineral groups was determined using sequential extraction. Structurally bound Li, predominantly in clays, accounted for 75-91 wt. % of total Li, whereas exchangeable sites and carbonate cement contain negligible Li (shale in Greene Co., Pennsylvania, and Tioga Co., New York, ranged from -2.3 to + 4.3‰, similar to values reported for other shales in the literature. The δ7Li values in shale rocks with stratigraphic depth record progressive weathering of the source region; the most weathered and clay-rich strata with isotopically light Li are found closest to the top of the stratigraphic section. Diagenetic illite-smectite transition could also have partially affected the bulk Li content and isotope ratios of the Marcellus Shale.

  2. Factors controlling Li concentration and isotopic composition in formation waters and host rocks of Marcellus Shale, Appalachian Basin

    Science.gov (United States)

    Phan, Thai T.; Capo, Rosemary C; Stewart, Brian W.; Macpherson, Gwen; Rowan, Elisabeth L.; Hammack, Richard W.

    2015-01-01

    In this study, water and whole rock samples from hydraulically fractured wells in the Marcellus Shale (Middle Devonian), and water from conventional wells producing from Upper Devonian sandstones were analyzed for lithium concentrations and isotope ratios (δ7Li). The distribution of lithium concentrations in different mineral groups was determined using sequential extraction. Structurally bound Li, predominantly in clays, accounted for 75-91 wt. % of total Li, whereas exchangeable sites and carbonate cement contain negligible Li (< 3%). Up to 20% of the Li is present in the oxidizable fraction (organic matter and sulfides). The δ7Li values for whole rock shale in Greene Co., Pennsylvania, and Tioga Co., New York, ranged from -2.3 to + 4.3‰, similar to values reported for other shales in the literature. The δ7Li values in shale rocks with stratigraphic depth record progressive weathering of the source region; the most weathered and clay-rich strata with isotopically light Li are found closest to the top of the stratigraphic section. Diagenetic illite-smectite transition could also have partially affected the bulk Li content and isotope ratios of the Marcellus Shale.

  3. Geomagnetic Reversals of the Late Jurassic and Early Cretaceous Captured in a North China Core

    Science.gov (United States)

    Kuhn, T.; Fu, R. R.; Kent, D. V.; Olsen, P. E.

    2016-12-01

    The Tuchengzi formation in North China nominally spans nearly 20 million years of the Late Jurassic and Early Cretaceous, an interval during which age calibration of the Geomagnetic Polarity Time Scale (GPTS) based on seafloor magnetic anomalies is poorly known. The overlying Yixian formation is of special paleontological interest due to an abundance of spectacularly preserved macrofossils of feathered non-avian dinosaurs, birds, mammals, and insects. Scarce fossils in the Tuchengzi, sparse accurate radiometric dates on both the Tuchengzi and overlying Yixian formation, and scant previous paleomagnetic studies on these formations motivated our application of magnetostratigraphy as a geochronological tool. We constructed a geomagnetic reversal sequence from the upper 142m of a 200m core extracted in Liaoning Province at Huangbanjigou spanning the lower Yixian Formation and the unconformably underlying Tuchengzi Formation. Thermal demagnetization up to 680°C in steps of 25-50°C revealed predominantly normal overprints consistent with the modern day field with unblocking temperatures between 125°C and as high as 550°C, as well as normal and reverse characteristic components with unblocking temperatures between 500°C and 680°C. Going up from the base of the core, there is a reverse polarity magnetozone >6m thick, followed by a 5m normal magnetozone, a 10m reverse magnetozone, a 25m normal magnetozone, and a 6m reverse magnetozone truncated by the Yixian-Tuchengzi unconformity. Above the unconformity, all 81m of core were normal. These results indicate that a meaningful polarity stratigraphy can be recovered from the Tuchengzi and Yixian formations that will be invaluable for correlations across the Tuchengzi and potentially the Yixian formations, which span thousands of square kilometers and vary in thickness by many hundreds of meters. The results also demonstrate that, in combination with accurate and precise radiometric dates, the Tuchengzi Formation has the

  4. Structuring of The Jurassic Basin of Chott in Gabes region (Southern Tunisia) associated to the Liassic rifting from geophysical and well data

    Science.gov (United States)

    Hassine, Mouna; Abbes, Chedly; Azaiez, Hajer; Gabtni, Hakim; Bouzid, Wajih

    2016-04-01

    The graben system of El Hamma, west of Gabes in Tunisia, corresponds to a pull apart basin developed in an extensive relay zone between two principal shear corridors (PSC) with a dextral sliding of N110-120 average direction. These PSC corresponds to two segments of the south-Atlasic shear corridor of NW-SE direction, which extends from Chott El Hodna in Algeria, to the NW, to the Libyan Djeferra to the SE (M.Hassine and al., 2015; M.Hassine and al., work in progress). This work aims to define the basin structuring during the Jurassic, especially from the Upper Lias during the Liassic rifting. For this, we performed seismic, gravity and well data analysis. Several wells situated in this basin and on its edges, which totally or partly crossed the Jurassic series which were described by several authors (J. Bonnefous, 1972 ; M. Soussi, 2002, 2004). These series corresponds to the Nara formation (PF Burollet, 1956) elevated to a group rank by M. Soussi (2003). It consists of two carbonate units separated by a marl-carbonate and sandstone member, dated successively of lower Lias (Hettangian- lower Pliensbachian.), Toarcian to Callovian and Upper Callovian-Tithonian. The correlation of this Jurassic formations along a North-South transect shows, from the South to the North, a significant variation in facies and thickness of the Jurassic series especially from the Upper Lias. Two resistant moles appears to the Northern and Southern edges of the pull-apart basin of El Hamma. The trend reversal of the lateral evolution of this series take place on the border NW-SE faults of the basin (PSC). The analysis of several seismic lines calibrated to well data, reveals a differentiated structuring inside the pull-apart basin itself, associated on the one hand, to the play of the N160 and N130-140 direction fault network which structure the basin in horsts and grabens of second order ( M. Hassine and al., 2015); and on the other hand, to the rise of the upper Triassic evaporates

  5. Evaluating possible industrial applications of combustible shales and shale ash wastes

    Directory of Open Access Journals (Sweden)

    Н. К. Кондрашева

    2016-08-01

    Full Text Available Today energy consumption is constantly growing while explored reserves of easily accessible oil are depleting, which is a reason why most countries tend to diversify their energy mix, develop non-hydrocarbon energy sources and use domestic types of fuel, including the low grade ones. Thereby interest is raised to such a source of hydrocarbons as combustible shales. Combustible shales appear to be one of the highest-potential types of organic raw materials, which may offset and in future even substitute oil products and gas. The paper is investigating behavior and structure of combustible shales during heat treatment in order to identify their possible industrial applications. A synchronous thermal analysis has been held, chemical composition of combustible shales’ mineral fraction and optimal conditions for shale fines briquetting have been determined.

  6. Permeability - Fluid Pressure - Stress Relationship in Fault Zones in Shales

    Science.gov (United States)

    Henry, P.; Guglielmi, Y.; Morereau, A.; Seguy, S.; Castilla, R.; Nussbaum, C.; Dick, P.; Durand, J.; Jaeggi, D.; Donze, F. V.; Tsopela, A.

    2016-12-01

    Fault permeability is known to depend strongly on stress and fluid pressures. Exponential relationships between permeability and effective pressure have been proposed to approximate fault response to fluid pressure variations. However, the applicability of these largely empirical laws remains questionable, as they do not take into account shear stress and shear strain. A series of experiments using mHPP probes have been performed within fault zones in very low permeability (less than 10-19 m2) Lower Jurassic shale formations at Tournemire (France) and Mont Terri (Switzerland) underground laboratories. These probes allow to monitor 3D displacement between two points anchored to the borehole walls at the same time as fluid pressure and flow rate. In addition, in the Mont-Terri experiment, passive pressure sensors were installed in observation boreholes. Fracture transmissivity was estimated from single borehole pulse test, constant pressure injection tests, and cross-hole tests. It is found that the transmissivity-pressure dependency can be approximated with an exponential law, but only above a pressure threshold that we call the Fracture Opening Threshold (F.O.P). The displacement data show a change of the mechanical response across the F.O.P. The displacement below the F.O.P. is dominated by borehole response, which is mostly elastic. Above F.O.P., the poro-elasto-plastic response of the fractures dominates. Stress determinations based on previous work and on the analysis of slip data from mHPPP probe indicate that the F.O.P. is lower than the least principal stress. Below the F.O.P., uncemented fractures retain some permeability, as pulse tests performed at low pressures yield diffusivities in the range 10-2 to 10-5 m2/s. Overall, this dual behavior appears consistent with the results of CORK experiments performed in accretionary wedge decollements. Results suggest (1) that fault zones become highly permeable when approaching the critical Coulomb threshold (2

  7. RUSSIA DOESN’T SUPPORT «SHALE REVOLUTION»

    Directory of Open Access Journals (Sweden)

    S. S. Zhiltsov

    2015-01-01

    Full Text Available Growth of volumes of production of shale gas in the USA compelled Russia to pay attention to this type of resourses. The interest to shale gas in Russia was limited to discussions at the level of experts and reflection of importance of this problem in statements of politicians. In the next years in Russia don't plan production of shale gas commercially. It is connected with existence in Russia of considerable reserves of traditional natural gas, absence of exact data of reserves of shale gas, high costs of production, and also environmental risks which accompany development of fields of shale gas.

  8. Middle to Late Jurassic Tectonic Evolution of the Klamath Mountains, California-Oregon

    Science.gov (United States)

    Harper, Gregory D.; Wright, James E.

    1984-12-01

    The geochronology, stratigraphy, and spatial relationships of Middle and Late Jurassic terranes of the Klamath Mountains strongly suggest that they were formed in a single west-facing magmatic arc built upon older accreted terranes. A Middle Jurassic arc complex is represented by the volcanic rocks of the western Hayfork terrane and consanguineous dioritic to peridotitic plutons. New U/Pb zircon dates indicate that the Middle Jurassic plutonic belt was active from 159 to 174 Ma and is much more extensive than previously thought. This plutonic belt became inactive just as the 157 Ma Josephine ophiolite, which lies west and structurally below the Middle Jurassic arc, was generated. Late Jurassic volcanic and plutonic arc rocks (Rogue Formation and Chetco intrusive complex) lie outboard and structurally beneath the Josephine ophiolite; U/Pb and K/Ar age data indicate that this arc complex is coeval with the Josephine ophiolite. Both the Late Jurassic arc complex and the Josephine ophiolite are overlain by the "Galice Formation," a Late Jurassic flysch sequence, and are intruded by 150 Ma dikes and sills. The following tectonic model is presented that accounts for the age and distribution of these terranes: a Middle Jurassic arc built on older accreted terranes undergoes rifting at 160 Ma, resulting in formation of a remnant arc/back-arc basin/island arc triad. This system collapsed during the Late Jurassic Nevadan Orogeny (150 Ma) and was strongly deformed and stacked into a series of east-dipping thrust sheets. Arc magmatism was active both before and after the Nevadan Orogeny, but virtually ceased at 140 Ma.

  9. Jurassic onychites (arm hooks) from squid-like cephalopods from the Wessex Basin, southern England

    Science.gov (United States)

    Hart, Malcolm; Hughes, Zoe; Page, Kevin; Price, Gregory; Smart, Christopher

    2017-04-01

    Modern coleoid (squid-like) cephalopods have arms that carry arrays of both suckers and hardened, organic hooks. Fossil arm hooks have been known since the description of Sternberg in 1823, although he identified them as algal remains. During the twentieth century there have been a number of descriptions of hooks (Kulicki & Szaniawski, 1972; Clarke & Engeser, 1988). Kulicki & Szaniawski (1972) gave these 'morphotypes' names using a binomial classification though, with many lacking defined (and figured) holotypes and, in some cases, only one recorded specimen, some of their designations should be regarded as invalid. Some of their morphotypes have, however, been reported widely, from DSDP sites on the Falkland Plateau as well as New Zealand, Germany, Svalbard, Poland and the United Kingdom. Exceptional soft-bodied preservation of species such as Belemnotheutis antiquus (Pearce, 1847) from the Callovian-Oxfordian of Wiltshire (UK) and Clarkeiteuthis montefiore (Buckman, 1880) from the Sinemurian of Dorset (UK) has allowed the identification of the host animal of some morphotypes, though the majority remain un-attributable. In the Christian Malford lagerstätte (Upper Callovian) of Wiltshire large numbers of hooks (including forms described as Acanthuncus, Arites, Deinuncus, Falcuncus, Longuncus and Paraglycerites) are found associated with an abundance of statoliths (cephalopod 'ear bones') and macrofossil evidence of both belemnites and teuthids, some of which includes exceptional soft-bodied preservation (Wilby et al., 2004; Hart et al., 2016). Many of the hook types cannot, at present be assigned to known taxa of coleoid. In Belemnotheutis antiquus there appears to be one form of simple, slightly curved hook and their shape appears to remain constant throughout the Callovian -Kimmeridgian interval. In the Lias Group, hooks of Clarkeiteuthis are very different, with inflated, often bi-lobate bases and each arm often characterised by the presence of different shapes

  10. Electromagnetic De-Shaling of Coal

    NARCIS (Netherlands)

    De Jong, T.P.R.; Mesina, M.B.; Kuilman, W.

    2003-01-01

    The efficiency with which an electromagnetic sensor array is able to distinguish density and ash content of coal and shale mixtures was determined experimentally. The investigated sensor was originally designed for automatic metal detection and sorting in industrial glass recycle processing, where

  11. [Chemical hazards arising from shale gas extraction].

    Science.gov (United States)

    Pakulska, Daria

    2015-01-01

    The development of the shale industry is gaining momentum and hence the analysis of chemical hazards to the environment and health of the local population is extreiely timely and important. Chemical hazards are created during the exploitation of all minerals, but in the case of shale gas production, there is much more uncertainty as regards to the effects of new technologies application. American experience suggests the increasing risk of environmental contamination, mainly groundwater. The greatest, concern is the incomplete knowledge of the composition of fluids used for fracturing shale rock and unpredictability of long-term effects of hydraulic fracturing for the environment and health of residents. High population density in the old continent causes the problem of chemical hazards which is much larger than in the USA. Despite the growing public discontent data on this subject are limited. First of all, there is no epidemiological studies to assess the relationship between risk factors, such as air and water pollution, and health effects in populations living in close proximity to gas wells. The aim of this article is to identify and discuss existing concepts on the sources of environmental contamination, an indication of the environment elements under pressure and potential health risks arising from shale gas extraction.

  12. Chemical hazards arising from shale gas extraction

    Directory of Open Access Journals (Sweden)

    Daria Pakulska

    2015-02-01

    Full Text Available The development of the shale industry is gaining momentum and hence the analysis of chemical hazards to the environment and health of the local population is extremely timely and important. Chemical hazards are created during the exploitation of all minerals, but in the case of shale gas production, there is much more uncertainty as regards to the effects of new technologies application. American experience suggests the increasing risk of environmental contamination, mainly groundwater. The greatest concern is the incomplete knowledge of the composition of fluids used for fracturing shale rock and unpredictability of long-term effects of hydraulic fracturing for the environment and health of residents. High population density in the old continent causes the problem of chemical hazards which is much larger than in the USA. Despite the growing public discontent data on this subject are limited. First of all, there is no epidemiological studies to assess the relationship between risk factors, such as air and water pollution, and health effects in populations living in close proximity to gas wells. The aim of this article is to identify and discuss existing concepts on the sources of environmental contamination, an indication of the environment elements under pressure and potential health risks arising from shale gas extraction. Med Pr 2015;66(1:99–117

  13. Method of treating oil-bearing shale

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, N H

    1926-04-14

    The process is given for treating shale or other oil-bearing mineral which consists of the application of dry heat to render the oil soluble and subjects the product of the heat treatment to an operation to extract the soluble oils.

  14. Epistemic values in the Burgess Shale debate

    DEFF Research Database (Denmark)

    Baron, Christian

    2009-01-01

    Focusing primarily on papers and books discussing the evolutionary and systematic interpretation of the Cambrian animal fossils from the Burgess Shale fauna, this paper explores the role of epistemic values in the context of a discipline (paleontology) striving to establish scientific authority w...

  15. Fourier Transform Infrared Spectroscopic Determination of Shale ...

    African Journals Online (AJOL)

    A Classical Least Square (CLS) model was developed from the attenuated spectra of mixtures of five mineral standards chosen to represent the most frequently encountered minerals in shale-type reservoir rocks namely: quartz, illite/smectite (30:70), kaolinite, calcite and dolomite. The CLS model developed was able to ...

  16. Evaluation of waste disposal by shale fracturing

    International Nuclear Information System (INIS)

    Weeren, H.O.

    1976-02-01

    The shale fracturing process is evaluated as a means for permanent disposal of radioactive intermediate level liquid waste generated at the Oak Ridge National Laboratory. The estimated capital operating and development costs of a proposed disposal facility are compared with equivalent estimated costs for alternative methods of waste fixation

  17. Quantitative effects of the shale oil revolution

    International Nuclear Information System (INIS)

    Belu Mănescu, Cristiana; Nuño, Galo

    2015-01-01

    The aim of this paper is to analyze the impact of the so-called “shale oil revolution” on oil prices and economic growth. We employ a general equilibrium model of the world oil market in which Saudi Arabia is the dominant firm, with the rest of the producers as a competitive fringe. Our results suggest that most of the expected increase in US oil supply due to the shale oil revolution has already been incorporated into prices and that it will produce an additional increase of 0.2% in the GDP of oil importers in the period 2010–2018. We also employ the model to analyze the collapse in oil prices in the second half of 2014 and conclude that it was mainly due to positive unanticipated supply shocks. - Highlights: • We analyze the impact of the “shale oil revolution” on oil prices and economic growth. • We employ a general equilibrium model of the oil market in which Saudi Arabia is the dominant firm. • We find that most of the shale oil revolution is already priced in. • We also analyze the decline in oil prices in the second half of 2014. • We find that unanticipated supply shocks played the major role in the fall.

  18. Shale Gas Development and Drinking Water Quality.

    Science.gov (United States)

    Hill, Elaine; Ma, Lala

    2017-05-01

    The extent of environmental externalities associated with shale gas development (SGD) is important for welfare considerations and, to date, remains uncertain (Mason, Muehlenbachs, and Olmstead 2015; Hausman and Kellogg 2015). This paper takes a first step to address this gap in the literature. Our study examines whether shale gas development systematically impacts public drinking water quality in Pennsylvania, an area that has been an important part of the recent shale gas boom. We create a novel dataset from several unique sources of data that allows us to relate SGD to public drinking water quality through a gas well's proximity to community water system (CWS) groundwater source intake areas.1 We employ a difference-in-differences strategy that compares, for a given CWS, water quality after an increase in the number of drilled well pads to background levels of water quality in the geographic area as measured by the impact of more distant well pads. Our main estimate finds that drilling an additional well pad within 1 km of groundwater intake locations increases shale gas-related contaminants by 1.5–2.7 percent, on average. These results are striking considering that our data are based on water sampling measurements taken after municipal treatment, and suggest that the health impacts of SGD 1 A CWS is defined as the subset of public water systems that supplies water to the same population year-round. through water contamination remains an open question.

  19. Geochemical controls on groundwater chemistry in shales

    International Nuclear Information System (INIS)

    Von Damm, K.L.

    1989-01-01

    The chemistry of groundwaters is one of the most important parameters in determining the mobility of species within a rock formation. A three pronged approach was used to determine the composition of, and geochemical controls, on groundwaters specifically within shale formations: (1) available data were collected from the literature, the US Geological Survey WATSTORE data base, and field sampling, (2) the geochemical modeling code EQ3/6 was used to simulate interaction of various shales and groundwaters, and (3) several types of shale were reacted with synthetic groundwaters in the laboratory. The comparison of model results to field and laboratory data provide a means of validating the models, as well as a means of deconvoluting complex field interactions. Results suggest that groundwaters in shales have a wide range in composition and are primarily of the Na-Cl-HCO 3 - type. The constancy of the Na:Cl (molar) ratio at 1:1 and the Ca:Mg ratio from 3:1 to 1:1 suggests the importance of halite and carbonates in controlling groundwater compositions. In agreement with the reaction path modeling, most of the groundwaters are neutral to slightly alkaline at low temperatures. Model and experimental results suggest that reaction (1) at elevated temperatures, or (2) in the presence of oxygen will lead to more acidic conditions. Some acetate was found to be produced in the experiments; depending on the constraints applied, large amounts of acetate were produced in the model results. 13 refs., 1 tab

  20. Process of distillation of oil shale

    Energy Technology Data Exchange (ETDEWEB)

    Saxton, A L

    1968-08-16

    In an oil-shale distillation apparatus with a single retort, in which separate zones of preheating, distillation, combustion, and cooling are maintained, the operation is conducted at a presssure higher than the atmospheric pressure, preferably at a gage pressure between about 0.35 and 7.0 bars. This permits increasing the capacity of the installation.

  1. Furnace for distillation of shales, etc

    Energy Technology Data Exchange (ETDEWEB)

    Germain-Clergault, M

    1863-07-09

    Practical experience and continuous operation of 55 retorts for 5 years of the system of vertical retorts patented in 1857 (French Patent 18,422) has shown the advantages resulting from this furnace which gives over a mean yield of 5% of Auton shale, which is /sup 1///sub 2/% more than the old systems with a fuel economy varying from 15 to 20%.

  2. Shale gases, a windfall for France?

    International Nuclear Information System (INIS)

    Tonnac, Alain de; Perves, Jean-Pierre

    2013-11-01

    After having recalled the definition and origin of shale gases, the different non conventional gases and their exploitation techniques (hydraulic fracturing and horizontal drilling) this report examines whether these gases are an opportunity for France. Some characteristics and data of the fossil and gas markets are presented and commented: world primary energy consumption, proved reserves of non conventional gases and their locations, European regions which may possess reserves of shale gases and coal-bed methane, origins of gas imports in France. The second part addresses shale gas deposits and their exploitation: discussion of the influence of the various rock parameters, evolution of production. The third part discusses the exploitation techniques and specific drilling tools. The issue of exploitation safety and security is addressed as well as the associated controversies: about the pollution of underground waters, about the fact that deep drillings result in pollution, about the risks associated with hydraulic fracturing and injections of chemical products, about the hold on ground and site degradation, about water consumption, about pollution due to gas pipeline leakage, about seismic risk, about noise drawbacks, about risks for health, about exploration and production authorization and license, and about air pollution and climate. The last part addresses the French situation and its future: status of the energy bill, recommendations made by a previous government, cancellation of authorizations, etc. Other information are provided in appendix about non conventional hydrocarbons, about shale gas exploitation in the USA, and about the Lacq gas

  3. Total and the Algerian shale gas

    International Nuclear Information System (INIS)

    Chapelle, Sophie; Petitjean, Olivier; Maurin, Wilfried; Balvet, Jacqueline; Combes, Maxime; Geze, Francois; Hamouchene, Hamza; Hidouci, Ghazi; Malti, Hocine; Renaud, Juliette; Simon, Antoine; Titouche, Fateh

    2015-01-01

    This publication proposes a rather detailed and discussed overview of the movement of mobilisation of Algerian people (notably those living in the Sahara) against projects of exploration and exploitation of shale gases in Algeria by the Total group. The authors also recall and comment the long and heavy history of hydrocarbon management in Algeria, the role of international firms and of western interests (notably French interests) in this country, and the position of Total regarding the stake related to shale gases. The authors outline problems created by shale gas exploitation regarding water consumption and waste waters. They also notice that the safety of wells is at the centre of the protest. Problems raised by hydraulic fracturing are reviewed: seismic activity, chemical pollution, air pollution and greenhouse gases, landscape destruction. The attitude of the Algerian government is commented. Then, the authors try to identify and describe the action of Total in the Algerian shale gas sector, discuss the possible French influence, and outline the presence of Total all over the world in this sector

  4. Naval Petroleum and Oil Shale Reserves

    International Nuclear Information System (INIS)

    1992-01-01

    During fiscal year 1992, the reserves generated $473 million in revenues, a $181 million decrease from the fiscal year 1991 revenues, primarily due to significant decreases in oil and natural gas prices. Total costs were $200 million, resulting in net cash flow of $273 million, compared with $454 million in fiscal year 1991. From 1976 through fiscal year 1992, the Naval Petroleum and Oil Shale Reserves generated more than $15 billion in revenues and a net operating income after costs of $12.5 billion. In fiscal year 1992, production at the Naval Petroleum Reserves at maximum efficient rates yielded 26 million barrels of crude oil, 119 billion cubic feet of natural gas, and 164 million gallons of natural gas liquids. From April to November 1992, senior managers from the Naval Petroleum and Oil Shale Reserves held a series of three workshops in Boulder, Colorado, in order to build a comprehensive Strategic Plan as required by Secretary of Energy Notice 25A-91. Other highlights are presented for the following: Naval Petroleum Reserve No. 1--production achievements, crude oil shipments to the strategic petroleum reserve, horizontal drilling, shallow oil zone gas injection project, environment and safety, and vanpool program; Naval Petroleum Reserve No. 2--new management and operating contractor and exploration drilling; Naval Petroleum Reserve No. 3--steamflood; Naval Oil Shale Reserves--protection program; and Tiger Team environmental assessment of the Naval Petroleum and Oil Shale Reserves in Colorado, Utah, and Wyoming

  5. China organic-rich shale geologic features and special shale gas production issues

    Directory of Open Access Journals (Sweden)

    Yiwen Ju

    2014-06-01

    Full Text Available The depositional environment of organic-rich shale and the related tectonic evolution in China are rather different from those in North America. In China, organic-rich shale is not only deposited in marine environment, but also in non-marine environment: marine-continental transitional environment and lacustrine environment. Through analyzing large amount of outcrops and well cores, the geologic features of organic-rich shale, including mineral composition, organic matter richness and type, and lithology stratigraphy, were analyzed, indicating very special characteristics. Meanwhile, the more complex and active tectonic movements in China lead to strong deformation and erosion of organic-rich shale, well-development of fractures and faults, and higher thermal maturity and serious heterogeneity. Co-existence of shale gas, tight sand gas, and coal bed methane (CBM proposes a new topic: whether it is possible to co-produce these gases to reduce cost. Based on the geologic features, the primary production issues of shale gas in China were discussed with suggestions.

  6. Contaminants from Cretaceous Black Shale Part 1: Natural weathering processes controlling contaminant cycling in Mancos Shale, southwestern United States, with emphasis on salinity and selenium

    Science.gov (United States)

    Tuttle, Michele L.W.; Fahy, Juli W.; Elliott, John G.; Grauch, Richard I.; Stillings, Lisa L.

    2013-01-01

    Soils derived from black shale can accumulate high concentrations of elements of environmental concern, especially in regions with semiarid to arid climates. One such region is the Colorado River basin in the southwestern United States where contaminants pose a threat to agriculture, municipal water supplies, endangered aquatic species, and water-quality commitments to Mexico. Exposures of Cretaceous Mancos Shale (MS) in the upper basin are a major contributor of salinity and selenium in the Colorado River. Here, we examine the roles of geology, climate, and alluviation on contaminant cycling (emphasis on salinity and Se) during weathering of MS in a Colorado River tributary watershed. Stage I (incipient weathering) began perhaps as long ago as 20 ka when lowering of groundwater resulted in oxidation of pyrite and organic matter. This process formed gypsum and soluble organic matter that persist in the unsaturated, weathered shale today. Enrichment of Se observed in laterally persistent ferric oxide layers likely is due to selenite adsorption onto the oxides that formed during fluctuating redox conditions at the water table. Stage II weathering (pedogenesis) is marked by a significant decrease in bulk density and increase in porosity as shale disaggregates to soil. Rainfall dissolves calcite and thenardite (Na2SO4) at the surface, infiltrates to about 1 m, and precipitates gypsum during evaporation. Gypsum formation (estimated 390 kg m−2) enriches soil moisture in Na and residual SO4. Transpiration of this moisture to the surface or exposure of subsurface soil (slumping) produces more thenardite. Most Se remains in the soil as selenite adsorbed to ferric oxides, however, some oxidizes to selenate and, during wetter conditions is transported with soil moisture to depths below 3 m. Coupled with little rainfall, relatively insoluble gypsum, and the translocation of soluble Se downward, MS landscapes will be a significant nonpoint source of salinity and Se to the

  7. Shale as a radioactive waste repository: the importance of vermiculite

    Energy Technology Data Exchange (ETDEWEB)

    Komarneni, S; Roy, D M; Pennsylvania State Univ., University Park; USA). Materials Research Labs.)

    1979-01-01

    Cesium sorption and fixation properties of thirty shale minerals and shales were investigated in search of a criterion for the suitability of shales for a radioactive waste repository. Shales and illites containing vermiculite fixed the largest proportion of total Cs sorbed (up to 91%) against displacement with 0.1 N KCl. For example, a slate sample fixed 33% of the total Cs sorbed while its weathered counterpart in which chlorite had altered to vermiculite fixed 89% of the total Cs sorbed. Since Cs is one of the most soluble and hazardous radioactive ions, its containment is of great importance in safe radioactive waste disposal. Presence of vermiculite in a shale body may therefore, serve as one criterion in the selection of a suitable shale for radioactive waste disposal if and when shales in geologically stable areas are selected for repositories.

  8. Partial diagenetic overprint of late jurassic belemnites from New Zealand

    DEFF Research Database (Denmark)

    Ullmann, Clemens Vinzenz; Campbell, Hamish J.; Frei, Robert

    2013-01-01

    δ7Li values become more positive with progressive alteration. The direction and magnitude of the trends in the geochemical record indicate that one main phase of alteration that occurred in the Late Cretaceous caused most of the diagenetic signature in the calcite. Despite relatively deep burial......The preservation potential and trends of alteration of many isotopic systems (e.g. Li, Mg, Ca) that are measured in fossil carbonates are little explored, yet extensive paleoenvironmental interpretations have been made on the basis of these records. Here we present a geochemical dataset for a Late...... Jurassic (~153 Ma) belemnite (Belemnopsis sp.) from New Zealand that has been partially overprinted by alteration. We report the physical pathways and settings of alteration, the resulting elemental and isotopic trends including δ7Li values and Li/Ca ratios, and assess whether remnants of the primary shell...

  9. Geochemical Astro- and Geochronological Constraints on the Early Jurassic

    Science.gov (United States)

    Storm, M.; Condon, D. J.; Ruhl, M.; Jenkyns, H. C.; Hesselbo, S. P.; Al-Suwaidi, A. H.; Percival, L.

    2017-12-01

    The Early Jurassic Hettangian and Sinemurian time scales are poorly defined due to the lack of continuous geochemical records, and the temporal constrain of the Toarcian Oceanic Anoxic Event and associated global carbon cycle perturbation is afflicted by geochemical and biostratigraphical uncertainties of the existing radiometric dates from various volcanic ash bearing sections. Here we present a continuous, orbitally paced Hettangian to Pliensbachian carbon-isotope record of the Mochras drill-core (Cardigan bay Basin, UK). The record generates new insights into the evolution and driving mechanisms of the Early Jurassic carbon cycle, and is contributing to improve the Hettangian and Sinemurian time scale. Furthermore, we introduce a new high-resolution carbon-isotope chemostratigraphy, integrated with ammonite biostratigraphy and new U/Pb single zircon geochronology of the Las Overas section (Neuquén Basin, Argentina). The studied section comprises sediments from the tenuicostatum to Dumortiera Andean Ammonite zone (tenuicostatum to levesqui European standard zones). A stratigraphically expanded negative shift in d13Corg values, from -24‰ down to -32­‰, appears in the tenuicostatum and hoelderi ammonite zone, coeval to the negative excursion in European realm which is associated with the Toarcian Oceanic Anoxic Event. The negative isotope excursion appears concomitant with an increase in sedimentary mercury levels, indicating enhanced volcanic activity. TOC values and elemental data suggest a high sedimentation dilution in the tenuicostatum to pacificum zone. The new geochronological data from several volcanic ash beds throughout the section are further improving the temporal correlation between the Early Toarcian isotope event and causal mechanisms

  10. Broad-scale patterns of late jurassic dinosaur paleoecology.

    Science.gov (United States)

    Noto, Christopher R; Grossman, Ari

    2010-09-03

    There have been numerous studies on dinosaur biogeographic distribution patterns. However, these distribution data have not yet been applied to ecological questions. Ecological studies of dinosaurs have tended to focus on reconstructing individual taxa, usually through comparisons to modern analogs. Fewer studies have sought to determine if the ecological structure of fossil assemblages is preserved and, if so, how dinosaur communities varied. Climate is a major component driving differences between communities. If the ecological structure of a fossil locality is preserved, we expect that dinosaur assemblages from similar environments will share a similar ecological structure. This study applies Ecological Structure Analysis (ESA) to a dataset of 100+ dinosaur taxa arranged into twelve composite fossil assemblages from around the world. Each assemblage was assigned a climate zone (biome) based on its location. Dinosaur taxa were placed into ecomorphological categories. The proportion of each category creates an ecological profile for the assemblage, which were compared using cluster and principal components analyses. Assemblages grouped according to biome, with most coming from arid or semi-arid/seasonal climates. Differences between assemblages are tied to the proportion of large high-browsing vs. small ground-foraging herbivores, which separates arid from semi-arid and moister environments, respectively. However, the effects of historical, taphonomic, and other environmental factors are still evident. This study is the first to show that the general ecological structure of Late Jurassic dinosaur assemblages is preserved at large scales and can be assessed quantitatively. Despite a broad similarity of climatic conditions, a degree of ecological variation is observed between assemblages, from arid to moist. Taxonomic differences between Asia and the other regions demonstrate at least one case of ecosystem convergence. The proportion of different ecomorphs, which

  11. Isopach map of interval between top of the Pictured Cliffs Sandstone and the Huerfanito Bentonite bed of the Lewis Shale, La Plata County, Colorado, and Rio Arriba and San Juan counties, New Mexico

    Science.gov (United States)

    Sandberg, D.T.

    1986-01-01

    This thickness map of a Late Cretaceous interval in the northwestern part of the San Juan Basin is part of a study of the relationship between ancient shore 1ines and coal-forming swamps during the filial regression of the Cretaceous epicontinental sea. The top of the thickness interval is the top of the Pictured Cliffs Sands tone. The base of the interval is a thin time marker, the Huerfanito Bentonite Bed of the Lewis Shale. The interval includes all of the Pictured Cliffs Sandstone and the upper part of the Lewis Shale. The northwest boundary of the map area is the outcrop of the Pictured Cliffs Sandstone and the Lewis Shale.

  12. A review of the organic geochemistry of shales and possible interactions between the organic matter of shales and radionuclides

    International Nuclear Information System (INIS)

    Ho, P.C.

    1990-01-01

    Shale formations have been suggested as potential host rocks for high level nuclear waste repositories. Several studies have demonstrated the interactions of nuclides with organic compounds found in shales. In order to understand the possibility of interaction between organic components of shales and trace elements, literature on the identification of organic compounds from various shales of the continental United States and evidences of interactions have been reviewed first. The Green River Formation of the Cenozoic era is the most studied shale followed by the Pierre Shale of the Mesozoic era and the Devonian Black Shale of the Paleozoic era. Organic compounds that have been identified from these shales are mainly hydrocarbons and carboxylates along with small amounts of other compounds. These organic compounds, however, constitute only a small fraction of the organic matter in shales; the majority of the organic compounds in shales are still unidentified. Interaction between organics and trace elements are found mostly due to the formation of complexes between carboxylates of shales and the elements. (orig.)

  13. Petrogenesis of volcanic rocks that host the world-class Agsbnd Pb Navidad District, North Patagonian Massif: Comparison with the Jurassic Chon Aike Volcanic Province of Patagonia, Argentina

    Science.gov (United States)

    Bouhier, Verónica E.; Franchini, Marta B.; Caffe, Pablo J.; Maydagán, Laura; Rapela, Carlos W.; Paolini, Marcelo

    2017-05-01

    We present the first study of the volcanic rocks of the Cañadón Asfalto Formation that host the Navidad world-class Ag + Pb epithermal district located in the North Patagonian Massif, Patagonia, Argentina. These volcanic and sedimentary rocks were deposited in a lacustrine environment during an extensional tectonic regime associated with the breakup of Gondwana and represent the mafic to intermediate counterparts of the mainly silicic Jurassic Chon Aike Volcanic Province. Lava flows surrounded by autobrecciated carapace were extruded in subaerial conditions, whereas hyaloclastite and peperite facies suggest contemporaneous subaqueous volcanism and sedimentation. LA-ICPMS Usbnd Pb ages of zircon crystals from the volcanic units yielded Middle Jurassic ages of 173.9 ± 1.9 Ma and 170.8 ± 3 Ma. In the Navidad district, volcanic rocks of the Cañadón Asfalto Formation show arc-like signatures including high-K basaltic-andesite to high-K dacite compositions, Rb, Ba and Th enrichment relative to the less mobile HFS elements (Nb, Ta), enrichment in light rare earth elements (LREE), Ysbnd Ti depletion, and high Zr contents. These characteristics could be explained by assimilation of crustal rocks in the Jurassic magmas, which is also supported by the presence of zircon xenocrysts with Permian and Middle-Upper Triassic ages (281.3 Ma, 246.5, 218.1, and 201.3 Ma) and quartz xenocrysts recognized in these volcanic units. Furthermore, Sr and Nd isotope compositions suggest a contribution of crustal components in these Middle Jurassic magmas. High-K basaltic andesite has initial 87Sr/86Sr ratios of 0.70416-0.70658 and ξNd(t) values of -5.3 and -4. High-K dacite and andesite have initial 87Sr/86Sr compositions of 0.70584-0.70601 and ξNd(t) values of -4,1 and -3,2. The range of Pb isotope values (206Pb/204Pb = 18.28-18.37, 207Pb/204Pb = 15.61-15.62, and 208Pb/204Pb = 38.26-38.43) of Navidad volcanic rocks and ore minerals suggest mixing Pb sources with contributions of

  14. Evolution of the Toarcian (Early Jurassic) carbon-cycle and global climatic controls on local sedimentary processes (Cardigan Bay Basin, UK)

    Science.gov (United States)

    Xu, Weimu; Ruhl, Micha; Jenkyns, Hugh C.; Leng, Melanie J.; Huggett, Jennifer M.; Minisini, Daniel; Ullmann, Clemens V.; Riding, James B.; Weijers, Johan W. H.; Storm, Marisa S.; Percival, Lawrence M. E.; Tosca, Nicholas J.; Idiz, Erdem F.; Tegelaar, Erik W.; Hesselbo, Stephen P.

    2018-02-01

    The late Early Jurassic Toarcian Stage represents the warmest interval of the Jurassic Period, with an abrupt rise in global temperatures of up to ∼7 °C in mid-latitudes at the onset of the early Toarcian Oceanic Anoxic Event (T-OAE; ∼183 Ma). The T-OAE, which has been extensively studied in marine and continental successions from both hemispheres, was marked by the widespread expansion of anoxic and euxinic waters, geographically extensive deposition of organic-rich black shales, and climatic and environmental perturbations. Climatic and environmental processes following the T-OAE are, however, poorly known, largely due to a lack of study of stratigraphically well-constrained and complete sedimentary archives. Here, we present integrated geochemical and physical proxy data (high-resolution carbon-isotope data (δ13 C), bulk and molecular organic geochemistry, inorganic petrology, mineral characterisation, and major- and trace-element concentrations) from the biostratigraphically complete and expanded entire Toarcian succession in the Llanbedr (Mochras Farm) Borehole, Cardigan Bay Basin, Wales, UK. With these data, we (1) construct the first high-resolution biostratigraphically calibrated chemostratigraphic reference record for nearly the complete Toarcian Stage, (2) establish palaeoceanographic and depositional conditions in the Cardigan Bay Basin, (3) show that the T-OAE in the hemipelagic Cardigan Bay Basin was marked by the occurrence of gravity-flow deposits that were likely linked to globally enhanced sediment fluxes to continental margins and deeper marine (shelf) basins, and (4) explore how early Toarcian (tenuicostatum and serpentinum zones) siderite formation in the Cardigan Bay Basin may have been linked to low global oceanic sulphate concentrations and elevated supply of iron (Fe) from the hinterland, in response to climatically induced changes in hydrological cycling, global weathering rates and large-scale sulphide and evaporite deposition.

  15. Paleontology, sedimentology and paleoenvironment of a new fossiliferous locality of the Jurassic Cañadón Asfalto Formation, Chubut Province, Argentina

    Science.gov (United States)

    Gallego, Oscar F.; Cabaleri, Nora G.; Armella, Claudia; Volkheimer, Wolfgang; Ballent, Sara C.; Martínez, Sergio; Monferran, Mateo D.; Silva Nieto, Diego G.; Páez, Manuel A.

    2011-02-01

    A new Late Jurassic assemblage of “conchostracans”, ostracods, bivalves and caddisfly cases from the locality “Estancia La Sin Rumbo”, Chubut Province (Patagonia, Argentina) is recorded. The fossils occur in the upper part of an outcropping 45 m thick volcaniclastic lacustrine sequence of yellowish tuffs and tuffites of the Puesto Almada Member, which is the upper member of the Cañadón Asfalto Formation with U/Pb age of 161 ± 3 Ma. The sequence represents one sedimentary cycle composed of a (lower) hemicycle of expansion and a (higher) hemicycle of contraction of the water body. The invertebrates lived in small freshwater bodies during the periods of expansion of the lake. The occurrence of a great number of small spinicaudatans, associated with mud-cracks, is evidence of dry climatic conditions and suggests several local mortality events. The spinicaudatan record of the fushunograptid-orthestheriid (component of the Eosestheriopsis dianzhongensis fauna) and the presence of Congestheriella rauhuti Gallego and Shen, suggest a Late Jurassic (Oxfordian to Tithonian) age. Caddisfly cases are recorded for the first time in the Cañadón Asfalto Basin.

  16. The challenges of a possible exploitation of shale gas in Denmark

    Science.gov (United States)

    Jacobsen, Ole S.; Kidmose, Jacob; Johnsen, Anders R.; Gravesen, Peter; Schovsbo, Niels H.

    2017-04-01

    Extraction of shale gas has in recent years attracted increasing interest internationally and in Denmark. The potential areas for shale gas extraction from Alum shale in Denmark are defined as areas where Alum shale is at least 20 m thick, gas mature and buried at 1.5 to 7 km depth. Sweet Spots are areas where Alum shale potentially has a high utility value. Sweet Spots are identified and cover an area of approximately 6,800 km2 and are divided into two subareas; where the shale is at 1.5-5 km depth (2,400 km2) or at 5-7 km depth (4,400 km2). The shale in the upper depth interval has the greatest interest, as these areas are localized most accurate as the production from the deep interval is less costly. Many potential risks has been identified by exploitation of unconventional gas, of which groundwater contamination, waste management and radioactive substances are classified as the most important. The international literature reports a water demand with an average of about 18,000 m3 for older wells whereas newer fracking methods have less water usage. Based heron the estimated water consumption is between 20 million to 66 million m3 water in Danish shale gas production well and thus significantly in the total water budget. Consumption of water for shale gas will however be distributed over a number of years. The temporal development in water usage will depend on how quickly the gas wells are developed. The available groundwater resource in Denmark is estimated to about 1 billion m3 / year. Groundwater abstraction has been slightly falling the last decades and is now totally 700 million m3 / year. The use of surface water in Denmark is thus negligible. Although groundwater attraction is only 70 % of the available, the resource is overexploited in many areas due to water consumption is very unevenly distributed varying from region to region. The composition of potential hydraulic fracturing liquids in Denmark is at present unknown, but is expected to be selected

  17. The Jurassic of Denmark and Greenland: The Middle Jurassic of western and northern Europe: its subdivisions, geochronology and correlations

    Directory of Open Access Journals (Sweden)

    Callomon, John H.

    2003-10-01

    Full Text Available The palaeogeographic settings of Denmark and East Greenland during the Middle Jurassic are outlined. They lay in the widespread epicontinental seas that covered much of Europe in the post-Triassic transgression. It was a period of continuing eustatic sea-level rise, with only distant connections to world oceans: to the Pacific, via the narrow Viking Straits between Greenland and Norway and hence the arctic Boreal Sea to the north; and to the subtropical Tethys, via some 1200 km of shelf-seas to the south. The sedimentary history of the region was strongly influenced by two factors: tectonism and climate. Two modes of tectonic movement governed basinal evolution: crustal extension leading to subsidence through rifting, such as in the Viking and Central Grabens of the North Sea; and subcrustal thermal upwelling, leading to domal uplift and the partition of marine basins through emergent physical barriers, as exemplified by the Central North Sea Dome with its associated volcanics. The climatic gradient across the 30º of temperate latitude spanned by the European seas governed biotic diversity and biogeography, finding expression in rock-forming biogenic carbonates that dominate sediments in the south and give way to largely siliciclastic sediments in the north. Geochronology of unrivalled finesse is provided by standard chronostratigraphy based on the biostratigraphy of ammonites. The Middle Jurassic saw the onset of considerable bioprovincial endemisms in these guide-fossils, making it necessary to construct parallel standard zonations for Boreal, Subboreal or NW European and Submediterranean Provinces, of which the NW European zonation provides the primary international standard. The current versions of these zonations are presented and reviewed.

  18. Shale gas development impacts on surface water quality in Pennsylvania

    Science.gov (United States)

    Olmstead, Sheila M.; Muehlenbachs, Lucija A.; Shih, Jhih-Shyang; Chu, Ziyan; Krupnick, Alan J.

    2013-01-01

    Concern has been raised in the scientific literature about the environmental implications of extracting natural gas from deep shale formations, and published studies suggest that shale gas development may affect local groundwater quality. The potential for surface water quality degradation has been discussed in prior work, although no empirical analysis of this issue has been published. The potential for large-scale surface water quality degradation has affected regulatory approaches to shale gas development in some US states, despite the dearth of evidence. This paper conducts a large-scale examination of the extent to which shale gas development activities affect surface water quality. Focusing on the Marcellus Shale in Pennsylvania, we estimate the effect of shale gas wells and the release of treated shale gas waste by permitted treatment facilities on observed downstream concentrations of chloride (Cl−) and total suspended solids (TSS), controlling for other factors. Results suggest that (i) the treatment of shale gas waste by treatment plants in a watershed raises downstream Cl− concentrations but not TSS concentrations, and (ii) the presence of shale gas wells in a watershed raises downstream TSS concentrations but not Cl− concentrations. These results can inform future voluntary measures taken by shale gas operators and policy approaches taken by regulators to protect surface water quality as the scale of this economically important activity increases. PMID:23479604

  19. Comparative acute toxicity of shale and petroleum derived distillates.

    Science.gov (United States)

    Clark, C R; Ferguson, P W; Katchen, M A; Dennis, M W; Craig, D K

    1989-12-01

    In anticipation of the commercialization of its shale oil retorting and upgrading process, Unocal Corp. conducted a testing program aimed at better defining potential health impacts of a shale industry. Acute toxicity studies using rats and rabbits compared the effects of naphtha, Jet-A, JP-4, diesel and "residual" distillate fractions of both petroleum derived crude oils and hydrotreated shale oil. No differences in the acute oral (greater than 5 g/kg LD50) and dermal (greater than 2 g/kg LD50) toxicities were noted between the shale and petroleum derived distillates and none of the samples were more than mildly irritating to the eyes. Shale and petroleum products caused similar degrees of mild to moderate skin irritation. None of the materials produced sensitization reactions. The LC50 after acute inhalation exposure to Jet-A, shale naphtha, (greater than 5 mg/L) and JP-4 distillate fractions of petroleum and shale oils was greater than 5 mg/L. The LC50 of petroleum naphtha (greater than 4.8 mg/L) and raw shale oil (greater than 3.95 mg/L) also indicated low toxicity. Results demonstrate that shale oil products are of low acute toxicity, mild to moderately irritating and similar to their petroleum counterparts. The results further demonstrate that hydrotreatment reduces the irritancy of raw shale oil.

  20. The Impact of Global Warming and Anoxia on Marine Benthic Community Dynamics: an Example from the Toarcian (Early Jurassic)

    Science.gov (United States)

    Danise, Silvia; Twitchett, Richard J.; Little, Crispin T. S.; Clémence, Marie-Emilie

    2013-01-01

    The Pliensbachian-Toarcian (Early Jurassic) fossil record is an archive of natural data of benthic community response to global warming and marine long-term hypoxia and anoxia. In the early Toarcian mean temperatures increased by the same order of magnitude as that predicted for the near future; laminated, organic-rich, black shales were deposited in many shallow water epicontinental basins; and a biotic crisis occurred in the marine realm, with the extinction of approximately 5% of families and 26% of genera. High-resolution quantitative abundance data of benthic invertebrates were collected from the Cleveland Basin (North Yorkshire, UK), and analysed with multivariate statistical methods to detect how the fauna responded to environmental changes during the early Toarcian. Twelve biofacies were identified. Their changes through time closely resemble the pattern of faunal degradation and recovery observed in modern habitats affected by anoxia. All four successional stages of community structure recorded in modern studies are recognised in the fossil data (i.e. Stage III: climax; II: transitional; I: pioneer; 0: highly disturbed). Two main faunal turnover events occurred: (i) at the onset of anoxia, with the extinction of most benthic species and the survival of a few adapted to thrive in low-oxygen conditions (Stages I to 0) and (ii) in the recovery, when newly evolved species colonized the re-oxygenated soft sediments and the path of recovery did not retrace of pattern of ecological degradation (Stages I to II). The ordination of samples coupled with sedimentological and palaeotemperature proxy data indicate that the onset of anoxia and the extinction horizon coincide with both a rise in temperature and sea level. Our study of how faunal associations co-vary with long and short term sea level and temperature changes has implications for predicting the long-term effects of “dead zones” in modern oceans. PMID:23457537

  1. Can the US shale revolution be duplicated in Europe?

    International Nuclear Information System (INIS)

    Saussay, Aurelien

    2015-04-01

    Over the past decade, the rapid increase in shale gas and shale oil production in the United States has profoundly changed energy markets in North America, and has led to a significant decrease in American natural gas prices. The possible existence of large shale deposits in Europe, mainly in France, Poland and the United Kingdom, has fostered speculation on whether the 'shale revolution', and its accompanying macro-economic impacts, could be duplicated in Europe. However, a number of uncertainties, notably geological, technological and regulatory, make this possibility unclear. We present a techno-economic model, SHERPA (Shale Exploitation and Recovery Projection and Analysis), to analyze the main determinants of the profitability of shale wells and plays. We calibrate our model using production data from the leading American shale plays. We use SHERPA to estimate three shale gas production scenarios exploring different sets of geological and technical hypotheses for the largest potential holder of shale gas deposits in Europe, France. Even considering that the geology of the potential French shale deposits is favorable to commercial extraction, we find that under assumptions calibrated on U.S. production data, natural gas could be produced at a high breakeven price of $8.6 per MMBtu, and over a 45 year time-frame have a net present value of $19.6 billion - less than 1% of 2012 French GDP. However, the specificities of the European context, notably high deposit depth and stricter environmental regulations, could increase drilling costs and further decrease this low profitability. We find that a 40% premium over American drilling costs would make shale gas extraction uneconomical. Absent extreme well productivity, it appears very difficult for shale gas extraction to have an impact on European energy markets comparable to the American shale revolution. (author)

  2. Geology of the Devonian black shales of the Appalachian Basin

    Science.gov (United States)

    Roen, J.B.

    1984-01-01

    Black shales of Devonian age in the Appalachian Basin are a unique rock sequence. The high content of organic matter, which imparts the characteristic lithology, has for years attracted considerable interest in the shales as a possible source of energy. The recent energy shortage prompted the U.S. Department of Energy through the Eastern Gas Shales Project of the Morgantown Energy Technology Center to underwrite a research program to determine the geologic, geochemical, and structural characteristics of the Devonian black shales in order to enhance the recovery of gas from the shales. Geologic studies by Federal and State agencies and academic institutions produced a regional stratigraphic network that correlates the 15 ft black shale sequence in Tennessee with 3000 ft of interbedded black and gray shales in central New York. These studies correlate the classic Devonian black shale sequence in New York with the Ohio Shale of Ohio and Kentucky and the Chattanooga Shale of Tennessee and southwestern Virginia. Biostratigraphic and lithostratigraphic markers in conjunction with gamma-ray logs facilitated long-range correlations within the Appalachian Basin. Basinwide correlations, including the subsurface rocks, provided a basis for determining the areal distribution and thickness of the important black shale units. The organic carbon content of the dark shales generally increases from east to west across the basin and is sufficient to qualify as a hydrocarbon source rock. Significant structural features that involve the black shale and their hydrocarbon potential are the Rome trough, Kentucky River and Irvine-Paint Creek fault zone, and regional decollements and ramp zones. ?? 1984.

  3. Features of the first great shale gas field in China

    Directory of Open Access Journals (Sweden)

    Ruobing Liu

    2016-04-01

    Full Text Available On the 28th of November 2012, high shale gas flow was confirmed to be 203 × 103 m3 in Longmaxi Formation; this led to the discovery of the Fuling Shale Gas Field. On the 10th of July in 2014, the verified geological reserves of the first shale gas field in China were submitted to the National Reserves Committee. Practices of exploration and development proved that the reservoirs in the Fuling Shale Gas Field had quality shales deposited in the deep-shelf; the deep-shelf had stable distribution, great thickness with no interlayers. The shale gas field was characterized by high well production, high-pressure reservoirs, good gas elements, and satisfactory effects on testing production; it's from the mid-deep depth of the quality natural gas reservoirs that bore high pressure. Comprehensive studies on the regional sedimentary background, lithology, micropore structures, geophysical properties, gas sources, features of gas reservoirs, logging responding features, and producing features of gas wells showed the following: (1 The Longmaxi Formation in the Fuling Shale Gas Field belongs to deep-shelf environment where wells developed due to organic-rich shales. (2 Thermal evolution of shales in Longmaxi Formation was moderate, nanometer-level pores developed as well. (3 The shale gas sources came from kerogens the Longmaxi Formation itself. (4 The shale gas reservoirs of the Fuling Longmaxi Formation were similar to the typical geological features and producing rules in North America. The findings proved that the shale gas produced in the Longmaxi Formation in Fuling was the conventional in-situ detained, self-generated, and self-stored shale gas.

  4. First diagnostic marine reptile remains from the Aalenian (Middle Jurassic): a new ichthyosaur from southwestern Germany.

    Science.gov (United States)

    Maxwell, Erin E; Fernández, Marta S; Schoch, Rainer R

    2012-01-01

    The Middle Jurassic was a critical time in the evolutionary history of ichthyosaurs. During this time interval, the diverse, well-studied faunas of the Lower Jurassic were entirely replaced by ophthalmosaurids, a new group that arose sometime prior to the Aalenian-Bajocian boundary and by the latest middle Jurassic comprised the only surviving group of ichthyosaurs. Thus, the Middle Jurassic Aalenian-Bathonian interval (176-165 million years ago) comprises the time frame during which ophthalmosaurids not only originated but also achieved taxonomic dominance. However, diagnostic ichthyosaur remains have been described previously from only a single locality from this interval, from the Bajocian of Argentina. In this paper, we describe a new species of ichthyosaur based on a partial articulated specimen from the Middle Jurassic of southwestern Germany. This specimen was recovered from the Opalinuston Formation (early Aalenian) and is referable to Stenopterygius aaleniensis sp. nov. reflecting features of the skull and forefin. The genus Stenopterygius is diverse and abundant in the Lower Jurassic of Europe, but its presence has not previously been confirmed in younger (Middle Jurassic) rocks from the northern hemisphere. This specimen represents the only diagnostic ichthyosaur remains reported from the Aalenian. It bears numerous similarities in size and in morphology to the Lower Jurassic species of the genus Stenopterygius and provides additional evidence that the major ecological changes hypothesized to have occurred at the end of the Toarcian took place sometime after this point and most likely did not occur suddenly. There is currently no evidence for the presence of ophthalmosaurids in the northern hemisphere during the Aalenian-Bathonian interval.

  5. First diagnostic marine reptile remains from the Aalenian (Middle Jurassic: a new ichthyosaur from southwestern Germany.

    Directory of Open Access Journals (Sweden)

    Erin E Maxwell

    Full Text Available BACKGROUND: The Middle Jurassic was a critical time in the evolutionary history of ichthyosaurs. During this time interval, the diverse, well-studied faunas of the Lower Jurassic were entirely replaced by ophthalmosaurids, a new group that arose sometime prior to the Aalenian-Bajocian boundary and by the latest middle Jurassic comprised the only surviving group of ichthyosaurs. Thus, the Middle Jurassic Aalenian-Bathonian interval (176-165 million years ago comprises the time frame during which ophthalmosaurids not only originated but also achieved taxonomic dominance. However, diagnostic ichthyosaur remains have been described previously from only a single locality from this interval, from the Bajocian of Argentina. METHODOLOGY/PRINCIPAL FINDINGS: In this paper, we describe a new species of ichthyosaur based on a partial articulated specimen from the Middle Jurassic of southwestern Germany. This specimen was recovered from the Opalinuston Formation (early Aalenian and is referable to Stenopterygius aaleniensis sp. nov. reflecting features of the skull and forefin. The genus Stenopterygius is diverse and abundant in the Lower Jurassic of Europe, but its presence has not previously been confirmed in younger (Middle Jurassic rocks from the northern hemisphere. CONCLUSIONS/SIGNIFICANCE: This specimen represents the only diagnostic ichthyosaur remains reported from the Aalenian. It bears numerous similarities in size and in morphology to the Lower Jurassic species of the genus Stenopterygius and provides additional evidence that the major ecological changes hypothesized to have occurred at the end of the Toarcian took place sometime after this point and most likely did not occur suddenly. There is currently no evidence for the presence of ophthalmosaurids in the northern hemisphere during the Aalenian-Bathonian interval.

  6. Is Estonian oil shale beneficial in the future?

    International Nuclear Information System (INIS)

    Reinsalu, Enno

    1998-01-01

    Oil shale mining production reached its maximum level of 31.35·10 6 tonnes per year in 1980. After the eighties there was a steady decline in mining. The first scientific prognoses of the inescapable decrease in oil shale mining were published in 1988. According to this, the Estonian oil shale industry would vanish in the third decade of the next century. From the beginning of the nineties, the consumption and export of electricity have dropped in Estonia. The minimum level of oil shale mining was 13.5·10 6 tonnes per year. This occurred in 1994/1995. Some increase in consumption of electric power and oil shale began at the end of 1995. Oil shale processing began to increase gradually in 1993. Oil shale is the most important fuel in Estonia today. In 1997, oil shale provided 76% of Estonia's primary energy supply and accounted for 57% of its economic value. Oil shale is the cheapest fuel in Estonia. Nowadays, oil shale provides an essential part of the fuel supply in Estonia because it is considerably cheaper than other fuels. Oil shale costs EEK 12.16 per G J. At the same time, coal costs EEK 23.41 per G J and peat costs EEK 14.80 per G J (year 1997). There are three important customers of oil shale: the electric power company Eesti Energia, the oil processing company Kiviter and the factory Kunda Nordic Cement. In 1995, the power company utilised 81% of the oil shale mass and 77% of its heating value. The state energy policy inhibits increases in the oil shale price even though the mining infrastructure is decaying. Government price policies subside oil shale processing. The energy of oil shale processing is 1.9 times cheaper than the heating value of raw oil shale for power stations. It could be considered as a state subsidisation of oil and cement export at the expense of electricity. The subsidy assigned to oil processing was of EEK 124·10 6 and to the cement industry of EEK 8.4·10 6 in year 1997 (based on heating value). State regulation of prices and

  7. The importance of thermal behaviour and petrographic composition for understanding the characteristics of a Portuguese perhydrous Jurassic coal

    Energy Technology Data Exchange (ETDEWEB)

    Costa, A. [Centro de Geologia, Universidade do Porto (Portugal); Flores, D. [Centro de Geologia, Universidade do Porto (Portugal); Departamento de Geociencias, Ambiente e Ordenamento do Territorio, Faculdade de Ciencias, Universidade do Porto (Portugal); Suarez-Ruiz, I.; Pevida, C.; Rubiera, F. [Instituto Nacional del Carbon, (INCAR-CSIC), Oviedo (Spain); Iglesias, M.J. [Area de Quimica Organica, Universidad de Almeria (Spain)

    2010-12-01

    The perhydrous Batalha coal (Portugal) is found in the Cabacos and Montejunto Formation of the Oxfordian-Kimeridgian, Upper Jurassic age. From the macroscopic point of view, its appearance is similar to other perhydrous coals. Microscopically, the maceral group of huminite is the main organic component (96%), ulminite being the most important petrographic component, followed by textinite with resinite (4%) lumina filled. The huminite random reflectance is 0.33%. This coal is characterized by high H/C atomic ratio, and anomalous physical and chemical properties that are characteristic of perhydrous coals such as: (i) the absence of any correlation between reflectance and the chemical rank parameters; (ii) a lower real density than that of non-perhydrous coals; (iii) a high hydrogen content; and (iv) suppressed reflectance. Using its calorific value (moist, ash-free basis) as rank parameter, Batalha coal must be considered a subbituminous A coal. Hydrogen enrichment due to the presence of resinite has influenced the technological properties of this coal, namely: (i) reduction of the thermostability and decrease in the temperature of initial thermal decomposition due to, among other reasons, the existence of aliphatic structures with low dissociation energy bonds resulting from the presence of resinite; (ii) from the DTG profile, the volatile matter combustion and char combustion is not evident; (iii) development of chars made up of isotropic particles with angular edges, which is typical of a low rank coal; (iv) the evolution trend of gaseous compounds (CO, CO{sub 2} and CH{sub 4}) during pyrolysis; and, (v) an increase in its calorific value due to its hydrogen content. The study of this coal which is interbedded in Jurassic formations in the Lusitanian Basin of Portugal is a new contribution to the assessment of the evolution of organic matter in this area. (author)

  8. Paleomagnetism of Jurassic radiolarian chert above the Coast Range ophiolite at Stanley Mountain, California, and implications for its paleogeographic origins

    Science.gov (United States)

    Hagstrum, J.T.; Murchey, B.L.

    1996-01-01

    Upper Jurassic red tuffaceous chert above the Coast Range ophiolite at Stanley Mountain, California (lat 35??N, long 240??E), contains three components of remanent magnetization. The first component (A; removed by ???100-???200 ??C) has a direction near the present-day field for southern California and is probably a recently acquired thermoviscous magnetization. A second component (B; removed between ???100 and ???600 ??C) is identical to that observed by previous workers in samples of underlying pillow basalt and overlying terrigenous sedimentary rocks. This component has constant normal polarity and direction throughout the entire section, although these rocks were deposited during a mixed polarity interval of the geomagnetic field. The B magnetization, therefore, is inferred to be a secondary magnetization acquired during accretion, uplift, or Miocene volcanism prior to regional clockwise rotation. The highest temperature component (C; removed between ???480 and 680 ??C) is of dual polarity and is tentatively interpreted as a primary magnetization, although it fails a reversal test possibly due to contamination by B. Separation of the B and C components is best shown by samples with negative-inclination C directions, and a corrected mean direction using only these samples indicates an initial paleolatitude of 32??N ?? 8??. Paleobiogeographic models relating radiolarian faunal distribution patterns to paleolatitude have apparently been incorrectly calibrated using the overprint B component. Few other paleomagnetic data have been incorporated in these models, and faunal distribution patterns are poorly known and mostly unqualified. The available data, therefore, do not support formation of the Coast Range ophiolite at Stanley Mountain near the paleoequator or accretion at ???10??N paleolatitude, as has been previously suggested based on paleomagnetic data, but indicate deposition near expected paleolatitudes for North America (35??N ?? 4??) during Late Jurassic

  9. ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

    Energy Technology Data Exchange (ETDEWEB)

    Brandon C. Nuttall

    2005-01-01

    Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library were sampled to determine CO{sub 2} and CH{sub 4} adsorption isotherms. Sidewall core samples were acquired to investigate CO{sub 2} displacement of methane. An elemental capture spectroscopy log was acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 14 percent. CO{sub 2} adsorption capacities at 400 psi range from a low of 14 scf/ton in less organic-rich zones to more than 136 scf/ton. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO{sub 2} in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO{sub 2}, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

  10. American shale gas in the European air

    International Nuclear Information System (INIS)

    Chauveau, L.

    2015-01-01

    Belgian scientists have detected ethane in atmosphere samples from Switzerland. The origin of this ethane is highly likely to be linked to the production of shale gas in Northern America. These concentrations of ethane have been increasing by 5% a year since 2009 while they had been steadily decreasing by about 1% a year over the 2 previous decades. These releases of ethane are massive since they are detected in Europe while ethane's lifetime in the atmosphere is only 2 months. Ethane is exclusively released from natural gas leaks during extraction operations or tank filling. A measurement campaign involving infrared spectrometry stations around the world have shown that ethane is released only in the northern hemisphere. It also appears that the beginning of the increase coincides with the beginning of the industrial exploitation of shale gas in the U.S. (A.C.)

  11. Adsorption of xenon and krypton on shales

    Science.gov (United States)

    Podosek, F. A.; Bernatowicz, T. J.; Kramer, F. E.

    1981-01-01

    A method that uses a mass spectrometer as a manometer is employed in the measurement of Xe and Kr adsorption parameters on shales and related samples, where gas partial pressures were lower than 10 to the -11th atm, corresponding adsorption coverages are only small fractions of a monolayer, and Henry's Law behavior is expected and observed. Results show heats of adsorption in the 2-7 kcal/mol range, and Henry constants at 0-25 C of 1 cu cm STP/g per atmosphere are extrapolated. Although the adsorption properties obtained are variable by sample, the range obtained suggests that shales may be capable of an equilibrium adsorption with modern air high enough to account for a significant fraction of the atmospheric inventory of Xe, and perhaps even of Kr. This effect will nevertheless not account for the factor-of-25 defficiency of atmospheric Xe, in comparison with the planetary gas patterns observed in meteorites.

  12. Phase Equilibrium Modeling for Shale Production Simulation

    DEFF Research Database (Denmark)

    Sandoval Lemus, Diego Rolando

    is obtained for hydrocarbon mixtures. Such behavior is mainly caused by compositional changes in the bulk phase due to selective adsorption of the heavier components onto the rock, while the change in bubble point pressure is mainly due to capillary pressure. This study has developed several robust......Production of oil and gas from shale reservoirs has gained more attention in the past few decades due to its increasing economic feasibility and the size of potential sources around the world. Shale reservoirs are characterized by a more tight nature in comparison with conventional reservoirs......, having pore size distributions ranging in the nanometer scale. Such a confined nature introduces new challenges in the fluid phase behavior. High capillary forces can be experienced between the liquid and vapor, and selective adsorption of components onto the rock becomes relevant. The impact...

  13. Subsidence prediction in Estonia's oil shale mines

    International Nuclear Information System (INIS)

    Pastarus, J.R.; Toomik, A.

    2000-01-01

    This paper analysis the stability of the mining blocks in Estonian oil shale mines, where the room-and-pillar mining system is used. The pillars are arranged in a singular grid. The oil shale bed is embedded at the depth of 40-75 m. The processes in overburden rocks and pillars have caused the subsidence of the ground surface. The conditional thickness and sliding rectangle methods performed calculations. The results are presented by conditional thickness contours. Error does not exceed 4%. Model allows determining the parameters of spontaneous collapse of the pillars and surface subsidence. The surface subsidence parameters will be determined by conventional calculation scheme. Proposed method suits for stability analysis, failure prognosis and monitoring. 8 refs

  14. Post-Jurassic tectonic evolution of Southeast Asia

    Science.gov (United States)

    Zahirovic, Sabin; Seton, Maria; Dietmar Müller, R.; Flament, Nicolas

    2014-05-01

    The accretionary growth of Asia, linked to long-term convergence between Eurasia, Gondwana-derived blocks and the Pacific, resulted in a mosaic of terranes for which conflicting tectonic interpretations exist. Here, we propose solutions to a number of controversies related to the evolution of Sundaland through a synthesis of published geological data and plate reconstructions that reconcile both geological and geophysical constraints with plate driving forces. We propose that West Sulawesi, East Java and easternmost Borneo rifted from northern Gondwana in the latest Jurassic, collided with an intra-oceanic arc at ~115 Ma and subsequently sutured to Sundaland by 80 Ma. Although recent models argue that the Southwest Borneo core accreted to Sundaland at this time, we use volcanic and biogeographic constraints to show that the core of Borneo was on the Asian margin since at least the mid Jurassic. This northward transfer of Gondwana-derived continental fragments required a convergent plate boundary in the easternmost Tethys that we propose gave rise to the Philippine Archipelago based on the formation of latest Jurassic-Early Cretaceous supra-subduction zone ophiolites on Halmahera, Obi Island and Luzon. The Late Cretaceous marks the shift from Andean-style subduction to back-arc opening on the east Asian margin. Arc volcanism along South China ceased by ~60 Ma due to the rollback of the Izanagi slab, leading to the oceanward migration of the volcanic arc and the opening of the Proto South China Sea (PSCS). We use the Apennines-Tyrrhenian system in the Mediterranean as an analogue to model this back-arc. Continued rollback detaches South Palawan, Mindoro and the Semitau continental blocks from the stable east Asian margin and transfers them onto Sundaland in the Eocene to produce the Sarawak Orogeny. The extrusion of Indochina and subduction polarity reversal along northern Borneo opens the South China Sea and transfers the Dangerous Grounds-Reed Bank southward to

  15. Use for refuse of shale carbonization

    Energy Technology Data Exchange (ETDEWEB)

    1917-09-25

    A process is disclosed for using the refuse from the carbonization of bituminous shales in the preparation of light building material, characterized in that the pulverized material is mixed wet with a light filler, formed in a mold, and burned with or without the addition of clay or with the addition of binding and preserving material, preparing the mold from the pulverized material in the cold.

  16. Isothermal decomposition of Baltic oil shale

    Energy Technology Data Exchange (ETDEWEB)

    Aarna, A Ya

    1955-01-01

    Heating oil shale at 300/sup 0/ to 440/sup 0/C yields a primary tar. Longer heating, regardless of temperature, results in the formation of heavier tar fractions. Higher temperatures tend to increase the middle and high-boiling fractions and to increase the concentration of unsaturated hydrocarbons at the expense of saturated hydrocarbons. Phenols appear, even at lower heating temperatures, indicating that aromatic structures are present or generated during the process.

  17. Process for carbonizing coal, shale, wood, etc

    Energy Technology Data Exchange (ETDEWEB)

    Matthaei, K

    1924-05-08

    A process for carbonization of coal, shale, and wood, for recovering low temperature tar and other products in a rotary retort is described. The material to be carbonized is brought directly in contact with the heating medium, that is characterized in that the heating medium streams through the retort crosswise to the longitudinal axis. The temperature of this medium in the single retort segments can be regulated.

  18. Method of utilization of alum shales

    Energy Technology Data Exchange (ETDEWEB)

    Dahlerus, C G

    1908-07-04

    A procedure - by means of reducing smelting of bituminous alum shales in a closed furnace process with or without the use of additional fuel and without adding lime or other slag-forming material - to utilize the hydrocarbons and tar oils formed, and likewise the alkali, nitrogen, and sulfur compositions is given. This is accomplished by making these products follow the furnace gases, and later separating them from the gases by cooling for condensation. The patent contains one more claim.

  19. Shale gas. Opportunities and challenges for European energy markets

    Energy Technology Data Exchange (ETDEWEB)

    De Joode, J.; Plomp, A.J.; Ozdemir, O. [ECN Policy Studies, Petten (Netherlands)

    2013-02-15

    The outline of the presentation shows the following elements: Introduction (Shale gas revolution in US and the situation in the EU); What could be the impact of potential shale gas developments on the European gas market?; How may shale gas developments affect the role of gas in the transition of the power sector?; and Key messages. The key messages are (1) Prospects for European shale gas widely differ from US case (different reserve potential, different competition, different market dynamics); (2) Shale gas is unlikely to be a game changer in Europe; and (3) Impact of shale gas on energy transition in the medium and long term crucially depends on gas vs. coal prices and the 'penalty' on CO2 emissions.

  20. Plan for addressing issues relating to oil shale plant siting

    Energy Technology Data Exchange (ETDEWEB)

    Noridin, J. S.; Donovan, R.; Trudell, L.; Dean, J.; Blevins, A.; Harrington, L. W.; James, R.; Berdan, G.

    1987-09-01

    The Western Research Institute plan for addressing oil shale plant siting methodology calls for identifying the available resources such as oil shale, water, topography and transportation, and human resources. Restrictions on development are addressed: land ownership, land use, water rights, environment, socioeconomics, culture, health and safety, and other institutional restrictions. Descriptions of the technologies for development of oil shale resources are included. The impacts of oil shale development on the environment, socioeconomic structure, water availability, and other conditions are discussed. Finally, the Western Research Institute plan proposes to integrate these topics to develop a flow chart for oil shale plant siting. Western Research Institute has (1) identified relative topics for shale oil plant siting, (2) surveyed both published and unpublished information, and (3) identified data gaps and research needs. 910 refs., 3 figs., 30 tabs.

  1. Trace metal chemistry in the Marcellus shale

    Energy Technology Data Exchange (ETDEWEB)

    Bank, Tracy [University at Buffalo (United States)

    2010-07-01

    In recent years, due to the depletion of traditional fossil fuel resources and the rising price of energy, the production of unconventional gas has increased. Several black shales contain uranium both in insoluble species, U4+, and in soluble U6+ phase. Those two forms of uranium are weakly radioactive, however they are toxic and can lead to kidney and liver damage. The aim of this paper is to assess the oxidation state of uranium in the Marcellus shale formation. Samples were analyzed using several methods such as XRD, X-ray absorption near edge structure, and time of flight secondary ion mass spectrometry to determine the rock geochemistry and examine the interaction between the uranium and the hydrocarbons. It was found that uranium exists in both UO2 and U-C forms with a dominance of U6+. This study demonstrated that uranium is present in the Marcellus shale in both U4+ and U6+ states and that more research must therefore be undertaken to determine how to dispose of waste from drilling and fracking activities.

  2. The 'Shale Gas Revolution'. Hype and Reality

    International Nuclear Information System (INIS)

    Stevens, P.

    2010-09-01

    The 'shale gas revolution' - responsible for a huge increase in unconventional gas production in the US over the last couple of years - is creating huge investor uncertainties for international gas markets and renewables and could result in serious gas shortages in 10 years time. This report casts serious doubt over industry confidence in the 'revolution', questioning whether it can spread beyond the US, or indeed be maintained within it, as environmental concerns, high depletion rates and the fear that US circumstances may be impossible to replicate elsewhere, come to the fore. Investor uncertainty will reduce investment in future gas supplies to lower levels than would have happened had the 'shale gas revolution' not hit the headlines. While the markets will eventually solve this problem, rising gas demand and the long lead-in-times on most gas projects are likely to inflict high prices on consumers in the medium term. The uncertainties created by the 'shale gas revolution' are also likely to compound existing investor uncertainty in renewables for power generation in the aftermath of Copenhagen. The serious possibility of cheap, relatively clean gas may threaten investment in more expensive lower carbon technologies.

  3. Effect of thermal maturity on remobilization of molybdenum in black shales

    Science.gov (United States)

    Ardakani, Omid H.; Chappaz, Anthony; Sanei, Hamed; Mayer, Bernhard

    2016-09-01

    Molybdenum (Mo) concentrations in sedimentary records have been widely used as a method to assess paleo-redox conditions prevailing in the ancient oceans. However, the potential effects of post-depositional processes, such as thermal maturity and burial diagenesis, on Mo concentrations in organic-rich shales have not been addressed, compromising its use as a redox proxy. This study investigates the distribution and speciation of Mo at various thermal maturities in the Upper Ordovician Utica Shale from southern Quebec, Canada. Samples display maturities ranging from the peak oil window (VRo ∼ 1%) to the dry gas zone (VRo ∼ 2%). While our data show a significant correlation between total organic carbon (TOC) and Mo (R2 = 0.40, n = 28, P 30 ppm). Our results show the presence of two Mo species: molybdenite Mo(IV)S2 (39 ± 5%) and Mo(VI)-Organic Matter (61 ± 5%). This new evidence suggests that at higher thermal maturities, TSR causes sulfate reduction coupled with oxidation of organic matter (OM). This process is associated with H2S generation and pyrite formation and recrystallization. This in turn leads to the remobilization of Mo and co-precipitation of molybdenite with TSR-derived carbonates in the porous intervals. This could lead to alteration of the initial sedimentary signature of Mo in the affected intervals, hence challenging its use as a paleo-redox proxy in overmature black shales.

  4. Seismically induced shale diapirism: the Mine d'Or section, Vilaine estuary, Southern Brittany

    Science.gov (United States)

    van Vliet-Lanoe, B.; Hibsch, C.; Csontos, L.; Jegouzo, S.; Hallégouët, B.; Laurent, M.; Maygari, A.; Mercier, D.; Voinchet, P.

    2009-07-01

    The Pénestin section (southern Brittany) presents large regular undulations, commonly interpreted as evidence of periglacial pingos. It is an upper Neogene palaeoestuary of the Vilaine River reactivated during the middle Quaternary (middle terrace). It is incised into a thick kaolinitic saprolite and deformed by saprolite diapirs. This paper presents the arguments leading to a mechanistic interpretation of the deformations at Pénestin. Neither recent transpressive tectonics nor diagnostic evidence of periglacial pingo have been found despite evidence for a late paleo-permafrost. The major deformational process is shale diapirism, initially triggered by co-seismic water supply, with further loading and lateral spreading on an already deformed and deeply weathered basement, which allowed the shale diapirism to develop. Deformations are favoured by the liquefaction of the saprolite and a seaward mass movement and recorded, rather distant, effects of an earthquake (c. 280 ka B.P.) resulting from the progressive subsidence of the southern Armorican margin. These deformations triggered by an earthquake are similar to those induced by classical shale diapirism. They are probably common in tectonically active continental environments with shallow water table.

  5. Jurassic and Cretaceous clays of the northern and central North Sea hydrocarbon reservoirs reviewed

    Energy Technology Data Exchange (ETDEWEB)

    Wilkinson, M.; Haszeldine, R.S.; Fallick, A.E.

    2006-03-15

    illite occurs almost ubiquitously within the clastic sediments of the North Sea. An early pore-lining phase has been interpreted as both infiltrated clastic clay, and as an early diagenetic phase. Early clays may have been quite smectite-rich illites, or even discrete smectites. Later, fibrous illite is undoubtedly neoformed, and can degrade reservoir quality significantly. Both within sandstones and shales, there is an apparent increase in the K content deeper than 4 km of burial, which could be due to dilution of the early smectite-rich phase by new growth illite, or to the progressive illitization of existing I-S. Much of the 'illite' that has been dated by the K-Ar method may therefore actually be I-S. The factors that control the formation of fibrous illite are only poorly known, though temperature must play a role. Illite growth has been proposed for almost the entire range of diagenetic temperatures (e.g. 15-20{sup o}C, Brent Group; 35-40{sup o}C, Oxfordian Sand, Inner Moray Firth; 50-90{sup o}C, Brae formation; 100-110{sup o}C, Brent Group; 130-140{sup o}C, Haltenbanken). It seems unlikely that there is a threshold temperature below which illite growth is impossible (or too slow to be significant), though this is a recurring hypothesis in the literature. Instead, illite growth seems to be an event, commonly triggered by oil emplacement or another change in the physiochemical conditions within the sandstone, such as an episode of overpressure release. Hence fibrous illite can grow at any temperature encountered during diagenesis. Although there is an extensive dataset of K-Ar ages of authigenic illites from the Jurassic of the North Sea, there is no consensus as to whether the data are meaningful, or whether the purified illite samples prepared for analysis are so contaminated with detrital phases as to render the age data meaningless. At present it is unclear about how to resolve this problem, though there is some indication that chemical micro

  6. Process and apparatus for the distillation of shale and other bituminous substances

    Energy Technology Data Exchange (ETDEWEB)

    Aitken, H

    1883-01-14

    The upper part of a vertical retort used for distillation is made of fire-resisting material, and the lower part of iron. The firing is carried out on the grate, so that the gases play over and under the retorts. The distillation products are carried off through a condenser. For raising the heat in the retorts and for increasing the yield of distillation proudcts the lower part of the exhausted shale is removed from the retort and it is filled up again. The exhaust gases serve to warm up the air for combustion.

  7. Desert and groundwater dynamics of the Jurassic Navajo Sandstone, southeast Utah

    Science.gov (United States)

    Chan, M. A.; Hasiotis, S. T.; Parrish, J. T.

    2017-12-01

    The Jurassic Navajo Sandstone of southeastern Utah is a rich archive of a desert complex with an active groundwater system, influenced by climate changes and recharge from the Uncompahgre Uplift of the Ancestral Rocky Mountains. This eastern erg margin was dominated by dune deposits of large (>10 m thick) and small (m-scale) crossbedded sandstone sets. Within these porous deposits, common soft sediment deformation is expressed as contorted and upturned bedding, fluid escape structures, concentrations of clastic pipes with ring faults, and thick intervals of massive sandstone embedded in crossbedded sandstone. Collectively, these deformation features reflect changes and/or overpressure in the groundwater system. Interdune deposits record laterally variable bounding surfaces, resulting from the change in position of and proximity to the water table. Interdune modification by pedogenesis from burrows, roots, and trees suggest stable periods of moisture and water supply, as well as periodic drying expressed as polygonal cracked mud- to sand-cracked layers. Freshwater bedded and platy limestone beds represent lakes of decameter to kilometer extent, common in the upper part of the formation. Some carbonate springs that fed the lakes are preserved as limestone buildups (tufa mounds) with microbial structures. Extradunal deposits of rivers to small ephemeral streams show channelized and lenticular, subhorizontal, cm- to m-scale sandstone bodies with basal scours and rip-up clasts. Proxy records of the active hydrology imply a changing landscape at the Navajo desert's edge, punctuated by periods of significant rainfall, runoff, rivers, lakes, and springs, fed by high water table conditions to sustain periods of flourishing communities of plants, arthropods, reptiles, mammals, and dinosaurs. Strong ground motion perturbations periodically disrupted porous, water-saturated sands with possible surface eruptions, adding to the dynamic activity of the desert regime.

  8. AN EARLY JURASSIC SAUROPOD TOOTH FROM PATAGONIA (CAÑADÓN ASFALTO FORMATION: IMPLICATIONS FOR SAUROPOD DIVERSITY

    Directory of Open Access Journals (Sweden)

    Carballido, José L

    2017-12-01

    Full Text Available Eusauropods were a group of herbivorous dinosaurs that evolved during the Early Jurassic and dominated the terrestrial ecosystems throughout the Jurassic and Cretaceous. A peak of diversity is represented by the Late Jurassic, when most of the lineages of the derived clade, Neosauropoda, are represented. Different lineages of eusauropods differ in several morphological aspects, including a great diversity in gathering strategies, inferred by their dentition morphology and wear facets. Here we describe a new tooth morphotype that can be well differentiated from any other tooth recovered from the Cañadón Asfalto Formation (Lower Jurassic-Middle-Jurassic. Therefore this new tooth morphology increase the evidence of a high diversity of sauropods during that time as well as providing evidence of advanced characters in the dentition of some Early Jurassic sauropods (e.g., subcylindrical and narrow crowns with single apical wear facet.

  9. Fugitive Emissions from the Bakken Shale Illustrate Role of Shale Production in Global Ethane Shift

    Science.gov (United States)

    Kort, E. A.; Smith, M. L.; Murray, L. T.; Gvakharia, A.; Brandt, A. R.; Peischl, J.; Ryerson, T. B.; Sweeney, C.; Travis, K.

    2016-01-01

    Ethane is the second most abundant atmospheric hydrocarbon, exerts a strong influence on tropospheric ozone, and reduces the atmosphere's oxidative capacity. Global observations showed declining ethane abundances from 1984 to 2010, while a regional measurement indicated increasing levels since 2009, with the reason for this subject to speculation. The Bakken shale is an oil and gas-producing formation centered in North Dakota that experienced a rapid increase in production beginning in 2010. We use airborne data collected over the North Dakota portion of the Bakken shale in 2014 to calculate ethane emissions of 0.23 +/- 0.07 (2 sigma) Tg/yr, equivalent to 1-3% of total global sources. Emissions of this magnitude impact air quality via concurrent increases in tropospheric ozone. This recently developed large ethane source from one location illustrates the key role of shale oil and gas production in rising global ethane levels.

  10. Unconventional wisdom: an economic analysis of US shale gas and implications for the EU

    International Nuclear Information System (INIS)

    Spencer, Thomas; Sartor, Oliver; Mathieu, Mathilde

    2014-01-01

    Despite very low and ultimately unsustainable short-term prices of natural gas, the unconventional oil and gas revolution has had a minimal impact on the US macro-economy. We provide an upper-optimistic-estimate of its long-term effect on the level of US GDP (not its long-term annual growth rate) at about 0.84% between 2012 and 2035. Compared to an annual growth rate of 1.4%, this long-term increase is small. And we estimate its short-term stimulus effects at 0.88% of GDP during the 2007/8 to 2012 downturn. The unconventional oil and gas revolution has also had a minimal impact on US manufacturing, confined to gas-intensive sectors, which we calculate as making up about 1.2% of US GDP. There is thus no evidence that shale gas is driving an overall manufacturing renaissance in the US. Absent further policies, the US shale revolution will not lead to a significant, sustained decarbonization of the US energy mix nor will it assure US energy security. A reference scenario based on current policies sees US emissions stagnant at current levels out to 2040, clearly insufficient for a reasonable US contribution to global climate change mitigation. Oil imports continue to rise in monetary terms. While it can promote some coal to gas switching in the short term if additional policies are enacted, there is also the risk that the unconventional oil and gas revolution further locks the US into an energy- and emissions-intensive capital stock. It is unlikely that the EU will repeat the US experience in terms of the scale of unconventional oil and gas production. Uncertainty exists around the exact size of exploitable EU shale gas reserves; a median scenario would see the EU producing about 3-10% of its gas demand from shale gas by 2030-2035. The EU's fossil fuel import dependency will therefore continue to increase and its fossil fuel prices will remain largely determined by international markets. Shale production would not have significant macro-economic or competitiveness

  11. Problem of Production of Shale Gas in Germany

    OpenAIRE

    Nataliya K. Meden

    2014-01-01

    A bstract: Our magazine publishes a series of articles on shale gas in different countries. This article is about Germany, a main importer of Russian natural gas, so a perspective of exploitation of local shale gas resources is of a clear practical importance for Russia. We discuss external and internal factors which determine position of the German government concerning the shale gas excavation: policy of the USA and the EU, positions of German political parties, influence of the lobbying co...

  12. Is Shale Development Drilling Holes in the Human Capital Pipeline?

    OpenAIRE

    Rickman, Dan S.; Wang, Hongbo; Winters, John V.

    2016-01-01

    Using the Synthetic Control Method (SCM) and a novel method for measuring changes in educational attainment we examine the link between educational attainment and shale oil and gas extraction for the states of Montana, North Dakota, and West Virginia. The three states examined are economically-small, relatively more rural, and have high levels of shale oil and gas reserves. They also are varied in that West Virginia is intensive in shale gas extraction, while the other two are intensive in sh...

  13. A comprehensive environmental impact assessment method for shale gas development

    OpenAIRE

    Sun, Renjin; Wang, Zhenjie

    2015-01-01

    The great success of US commercial shale gas exploitation stimulates the shale gas development in China, subsequently, the corresponding supporting policies were issued in the 12th Five-Year Plan. But from the experience in the US shale gas development, we know that the resulted environmental threats are always an unavoidable issue, but no uniform and standard evaluation system has yet been set up in China. The comprehensive environment refers to the combination of natural ecological environm...

  14. Burning Poseidonian shale ash for production of cement

    Energy Technology Data Exchange (ETDEWEB)

    1919-10-28

    A process is described for the burning of shale coke obtained by the deoiling of Poseidonian or the usual kind of shale for the preparation of brick, mortar, or cement, characterized in that the shale coke is thrown on a pile and completely covered with burnt material, so that the gases drawn through this cover will be sufficiently choked to hold the feed at a high temperature as long as possible.

  15. Producing electricity from Israel oil shale with PFBC technology

    International Nuclear Information System (INIS)

    Grinberg, A.; Keren, M.; Podshivalov, V.; Anderson, J.

    2000-01-01

    Results of Israeli oil shale combustion at atmospheric pressure in the AFBC commercial boiler manufactured by Foster Wheeler Energia Oy (Finland) and in the pressurized test facility of ABB Carbon AB (Finspong, Sweden) confirm suitability of fluidized-bed technologies in case of oil shale. The results approve possibility to use the PFBC technology in case of oil shale after solving of some problems connected with great amounts of fine fly ash. (author)

  16. Research and information needs for management of oil shale development

    Energy Technology Data Exchange (ETDEWEB)

    1983-05-01

    This report presents information and analysis to assist BLM in clarifying oil shale research needs. It provides technical guidance on research needs in support of their regulatory responsibilities for onshore mineral activities involving oil shale. It provides an assessment of research needed to support the regulatory and managerial role of the BLM as well as others involved in the development of oil shale resources on public and Indian lands in the western United States.

  17. Acidization of shales with calcite cemented fractures

    Science.gov (United States)

    Kwiatkowski, Kamil; Szymczak, Piotr; Jarosiński, Marek

    2017-04-01

    Investigation of cores drilled from shale formations reveals a relatively large number of calcite-cemented fractures. Usually such fractures are reactivated during fracking and can contribute considerably to the permeability of the resulting fracture network. However, calcite coating on their surfaces effectively excludes them from production. Dissolution of the calcite cement by acidic fluids is investigated numerically with focus on the evolution of fracture morphology. Available surface area, breakthrough time, and reactant penetration length are calculated. Natural fractures in cores from Pomeranian shale formation (northern Poland) were analyzed and classified. Representative fractures are relatively thin (0.1 mm), flat and completely sealed with calcite. Next, the morphology evolution of reactivated natural fractures treated with low-pH fluids has been simulated numerically under various operating conditions. Depth-averaged equations for fracture flow and reactant transport has been solved by finite-difference method coupled with sparse-matrix solver. Transport-limited dissolution has been considered, which corresponds to the treatment with strong acids, such as HCl. Calcite coating in reactivated natural fractures dissolves in a highly non-homogeneous manner - a positive feedback between fluid transport and calcite dissolution leads to the spontaneous formation of wormhole-like patterns, in which most of the flow is focused. The wormholes carry reactive fluids deeper inside the system, which dramatically increases the range of the treatment. Non-uniformity of the dissolution patterns provides a way of retaining the fracture permeability even in the absence of the proppant, since the less dissolved regions will act as supports to keep more dissolved regions open. Evolution of fracture morphology is shown to depend strongly on the thickness of calcite layer - the thicker the coating the more pronounced wormholes are observed. However the interaction between

  18. Water Resources Management for Shale Energy Development

    Science.gov (United States)

    Yoxtheimer, D.

    2015-12-01

    The increase in the exploration and extraction of hydrocarbons, especially natural gas, from shale formations has been facilitated by advents in horizontal drilling and hydraulic fracturing technologies. Shale energy resources are very promising as an abundant energy source, though environmental challenges exist with their development, including potential adverse impacts to water quality. The well drilling and construction process itself has the potential to impact groundwater quality, however if proper protocols are followed and well integrity is established then impacts such as methane migration or drilling fluids releases can be minimized. Once a shale well has been drilled and hydraulically fractured, approximately 10-50% of the volume of injected fluids (flowback fluids) may flow out of the well initially with continued generation of fluids (produced fluids) throughout the well's productive life. Produced fluid TDS concentrations often exceed 200,000 mg/L, with elevated levels of strontium (Sr), bromide (Br), sodium (Na), calcium (Ca), barium (Ba), chloride (Cl), radionuclides originating from the shale formation as well as fracturing additives. Storing, managing and properly disposisng of these fluids is critical to ensure water resources are not impacted by unintended releases. The most recent data in Pennsylvania suggests an estimated 85% of the produced fluids were being recycled for hydraulic fracturing operations, while many other states reuse less than 50% of these fluids and rely moreso on underground injection wells for disposal. Over the last few years there has been a shift to reuse more produced fluids during well fracturing operations in shale plays around the U.S., which has a combination of economic, regulatory, environmental, and technological drivers. The reuse of water is cost-competitive with sourcing of fresh water and disposal of flowback, especially when considering the costs of advanced treatment to or disposal well injection and lessens

  19. Developments in production of synthetic fuels out of Estonian shale

    Energy Technology Data Exchange (ETDEWEB)

    Aarna, Indrek

    2010-09-15

    Estonia is still the world leader in utilization of oil shale. Enefit has cooperated with Outotec to develop a new generation of solid heat carrier technology - Enefit280, which is more efficient, environmentally friendlier and has higher unit capacity. Breakeven price of oil produced in Enefit280 process is competitive with conventional oils. The new technology has advantages that allow easy adaptation to other oil shales around the world. Hydrotreated shale oil liquids have similar properties to crude oil cuts. Design for a shale oil hydrotreater unit can use process concepts, hardware components, and catalysts commercially proven in petroleum refining services.

  20. Gas pressure from a nuclear explosion in oil shale

    International Nuclear Information System (INIS)

    Taylor, R.W.

    1975-01-01

    The quantity of gas and the gas pressure resulting from a nuclear explosion in oil shale is estimated. These estimates are based on the thermal history of the rock during and after the explosion and the amount of gas that oil shale releases when heated. It is estimated that for oil shale containing less than a few percent of kerogen the gas pressure will be lower than the hydrostatic pressure. A field program to determine the effects of nuclear explosions in rocks that simulate the unique features of oil shale is recommended. (U.S.)

  1. Geothermal alteration of clay minerals and shales: diagenesis

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, C.E.

    1979-07-01

    The objective of this report is to perform a critical review of the data on the mineral and chemical alterations that occur during diagenesis and low-grade metamorphism of shale and other clay-rich rocks - conditions similar to those expected from emplacement of heat-producing radioactive waste in a geologic repository. The conclusions drawn in this document are that the following type of alterations could occur: smectite alteration, ion mobilization, illitic shales, kaolinite reactions, chlorite reactions, organic reactions, paleotemperatures, low temperature shales, high temperature shales, and phase equilibrium changes.

  2. Geothermal alteration of clay minerals and shales: diagenesis

    International Nuclear Information System (INIS)

    Weaver, C.E.

    1979-07-01

    The objective of this report is to perform a critical review of the data on the mineral and chemical alterations that occur during diagenesis and low-grade metamorphism of shale and other clay-rich rocks - conditions similar to those expected from emplacement of heat-producing radioactive waste in a geologic repository. The conclusions drawn in this document are that the following type of alterations could occur: smectite alteration, ion mobilization, illitic shales, kaolinite reactions, chlorite reactions, organic reactions, paleotemperatures, low temperature shales, high temperature shales, and phase equilibrium changes

  3. Oil shales of the Lothians, Part III, the chemistry of the oil shales

    Energy Technology Data Exchange (ETDEWEB)

    Steuart, D R

    1912-01-01

    Tests were performed whereby fuller's earth and lycopodium spore dust were heated to retorting temperatures and the crude oil examined. Oil shale may be composed of the following: Vegetable matter that has been macerated and preserved by combining with salts, spores, and other such material that has been protected from decay, and a proportion of animal matter. Generally, oil shale may be considered as a torbanite that contains a large proportion of inorganic matter, or it may be a torbanite that has deteriorated with age. This supposition is based on the fact that oil yield decreases and the yield of ammonia increases with age.

  4. Oil shales of the Lothians. Part III. Chemistry of the oil shales

    Energy Technology Data Exchange (ETDEWEB)

    Steuart, D R

    1912-01-01

    Tests were performed whereby fuller's earth and lycopodium spore dust were heated to retorting temperatures and the crude oil examined. Oil shale may be composed of the following: vegetable matter that has been macerated and preserved by combining with salts, spores, and other such material that has been protected from decay, and a proportion of animal matter. Generally, oil shale may be considered as a torbanite that contains a large proportion of inorganic matter, or it may be a torbanite that has deteriorated with age. This supposition is based on the fact that oil yield decreases and the yield of ammonia increases with age.

  5. Experimental Study of Matrix Permeability of Gas Shale: An Application to CO2-Based Shale Fracturing

    Directory of Open Access Journals (Sweden)

    Chengpeng Zhang

    2018-03-01

    Full Text Available Because the limitations of water-based fracturing fluids restrict their fracturing efficiency and scope of application, liquid CO2 is regarded as a promising substitute, owing to its unique characteristics, including its greater environmental friendliness, shorter clean-up time, greater adsorption capacity than CH4 and less formation damage. Conversely, the disadvantage of high leak-off rate of CO2 fracturing due to its very low viscosity determines its applicability in gas shales with ultra-low permeability, accurate measurement of shale permeability to CO2 is therefore crucial to evaluate the appropriate injection rate and total consumption of CO2. The main purpose of this study is to accurately measure shale permeability to CO2 flow during hydraulic fracturing, and to compare the leak-off of CO2 and water fracturing. A series of permeability tests was conducted on cylindrical shale samples 38 mm in diameter and 19 mm long using water, CO2 in different phases and N2 considering multiple influencing factors. According to the experimental results, the apparent permeability of shale matrix to gaseous CO2 or N2 is greatly over-estimated compared with intrinsic permeability or that of liquid CO2 due to the Klinkenberg effect. This phenomenon explains that the permeability values measured under steady-state conditions are much higher than those under transient conditions. Supercritical CO2 with higher molecular kinetic energy has slightly higher permeability than liquid CO2. The leak-off rate of CO2 is an order of magnitude higher than that of water under the same injection conditions due to its lower viscosity. The significant decrease of shale permeability to gas after water flooding is due to the water block effect, and much longer clean-up time and deep water imbibition depth greatly impede the gas transport from the shale matrix to the created fractures. Therefore, it is necessary to substitute water-based fracturing fluids with liquid or super

  6. Boron-containing organic pigments from a Jurassic red alga.

    Science.gov (United States)

    Wolkenstein, Klaus; Gross, Jürgen H; Falk, Heinz

    2010-11-09

    Organic biomolecules that have retained their basic chemical structures over geological periods (molecular fossils) occur in a wide range of geological samples and provide valuable paleobiological, paleoenvironmental, and geochemical information not attainable from other sources. In rare cases, such compounds are even preserved with their specific functional groups and still occur within the organisms that produced them, providing direct information on the biochemical inventory of extinct organisms and their possible evolutionary relationships. Here we report the discovery of an exceptional group of boron-containing compounds, the borolithochromes, causing the distinct pink coloration of well-preserved specimens of the Jurassic red alga Solenopora jurassica. The borolithochromes are characterized as complicated spiroborates (boric acid esters) with two phenolic moieties as boron ligands, representing a unique class of fossil organic pigments. The chiroptical properties of the pigments unequivocally demonstrate a biogenic origin, at least of their ligands. However, although the borolithochromes originated from a fossil red alga, no analogy with hitherto known present-day red algal pigments was found. The occurrence of the borolithochromes or their possible diagenetic products in the fossil record may provide additional information on the classification and phylogeny of fossil calcareous algae.

  7. Middle Jurassic - Early Cretaceous rifting of the Danish Central Graben

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, J.J.; Rasmussen, E.S.

    1998-12-01

    During the Jurassic-early Cretaceous, the Danish Central Graben developed as a N-S to NNW-SSE trending Graben bounded by the Ringkoebing-Fyn High towards the east and the Mid North Sea High towards the west. The Graben consists of a system of half-Grabens and evolved by fault-controlled subsidence; three main rift pulses have been recognized. The first pulse ranged from the Callovian to the early Oxfordian, the second pulse was initiated in the latest Late Kimmeridgian and Early Volgian, and the third and final pulse occurred within the Valanginian in the Early Cretaceous. The first pulse was characterized by subsidence along N-S trending faults. During the second pulse, in early Volgian times, subsidence was concentrated along new NNW-SSE trending faults and the main depocentre shifted westward, being most marked within the Tail End Graben, the Arne-Elin Graben, and the Feda Graben. This tectonic event was accompanied by the accumulation of a relatively thick sediment load resulting in the development of salt diapers, especially within the Salt Dome Province. The third tectonic pulse was essentially a reactivation of the NNW-SSE trending structures. This tectonic pulse also shows clear evidence of combined fault-controlled subsidence and salt movements. (EG) 12 figs.; 45 refs.

  8. A jurassic-cretaceous dolerite dike from Sri Lanka

    International Nuclear Information System (INIS)

    Yoshida, M.; Vitanage, P.W.

    1989-01-01

    A dolerite dike from southwestern Sri Lanka gave whole-rock K-Ar ages of 152.6 ± 7.6 Ma and 143.3 ± 7.2 Ma. Many of the other dolerite dikes of Sri Lanka are considered to be of Mesozoic ages judging from the present age data and tectonometamorphic history of Sri Lanka. Petrographic similarities should not be used for age correlations, because dolerites of different age may have the same petrography. Preliminary natural remanent magnetization (NRM) after AF and thermal demagnetization gave a mean inclination of 24.6deg and declination of 67.5deg with α95=21.7deg. A virtual geomagnetic pole position calculated from the mean NRM was rotated relative to Antarctica so as to fit with that obtained from the Jurassic Ferrar dolerite of Antarctica. This rotation results in the location and attitude of Sri Lanka to attach with Antarctica at Lutzow-Holm Bay as suggested by Barron et al. (1978). (author). 18 refs

  9. Ichnological evidence of Megalosaurid Dinosaurs Crossing Middle Jurassic Tidal Flats

    Science.gov (United States)

    Razzolini, Novella L.; Oms, Oriol; Castanera, Diego; Vila, Bernat; Santos, Vanda Faria Dos; Galobart, Àngel

    2016-08-01

    A new dinosaur tracksite in the Vale de Meios quarry (Serra de Aire Formation, Bathonian, Portugal)preserves more than 700 theropod tracks. They are organized in at least 80 unidirectional trackways arranged in a bimodal orientation pattern (W/NW and E/SE). Quantitative and qualitative comparisons reveal that the large tridactyl, elongated and asymmetric tracks resemble the typical Late Jurassic-Early Cretaceous Megalosauripus ichnogenus in all morphometric parameters. Few of the numerous tracks are preserved as elite tracks while the rest are preserved as different gradients of modified true tracks according to water content, erosive factors, radial fractures and internal overtrack formations. Taphonomical determinations are consistent with paleoenvironmental observations that indicate an inter-tidal flat located at the margin of a coastal barrier. The Megalosauripus tracks represent the oldest occurrence of this ichnotaxon and are attributed to large megalosaurid dinosaurs. Their occurrence in Vale de Meios tidal flat represents the unique paleoethological evidence of megalosaurids moving towards the lagoon, most likley during the low tide periods with feeding purposes.

  10. Neuroanatomy of the marine Jurassic turtle Plesiochelys etalloni (Testudinata, Plesiochelyidae).

    Science.gov (United States)

    Carabajal, Ariana Paulina; Sterli, Juliana; Müller, Johannes; Hilger, André

    2013-01-01

    Turtles are one of the least explored clades regarding endocranial anatomy with few available descriptions of the brain and inner ear of extant representatives. In addition, the paleoneurology of extinct turtles is poorly known and based on only a few natural cranial endocasts. The main goal of this study is to provide for the first time a detailed description of the neuroanatomy of an extinct turtle, the Late Jurassic Plesiochelysetalloni, including internal carotid circulation, cranial endocast and inner ear, based on the first digital 3D reconstruction using micro CT scans. The general shape of the cranial endocast of P. etalloni is tubular, with poorly marked cephalic and pontine flexures. Anteriorly, the olfactory bulbs are clearly differentiated suggesting larger bulbs than in any other described extinct or extant turtle, and indicating a higher capacity of olfaction in this taxon. The morphology of the inner ear of P. etalloni is comparable to that of extant turtles and resembles those of slow-moving terrestrial vertebrates, with markedly low, short and robust semicircular canals, and a reduced lagena. In P. etalloni the arterial pattern is similar to that found in extant cryptodires, where all the internal carotid branches are protected by bone. As the knowledge of paleoneurology in turtles is scarce and the application of modern techniques such as 3D reconstructions based on CT scans is almost unexplored in this clade, we hope this paper will trigger similar investigations of this type in other turtle taxa.

  11. Fish faunas from the Late Jurassic (Tithonian) Vaca Muerta Formation of Argentina: One of the most important Jurassic marine ichthyofaunas of Gondwana

    Science.gov (United States)

    Gouiric-Cavalli, Soledad; Cione, Alberto Luis

    2015-11-01

    The marine deposits of the Vaca Muerta Formation (Tithonian-Berriasian) houses one of the most diverse Late Jurassic ichthyofaunas of Gondwana. However, most of the specimens remain undescribed. Jurassic fishes have been recovered from several localities at Neuquén Province (i.e., Picún Leufú, Plaza Huincul, Cerro Lotena, Portada Las Lajas, Los Catutos, and Arroyo Covunco) but also from Mendoza Province (i.e., La Valenciana, Los Molles, and Arroyo del Cajón Grande). Presently, the fish fauna of Los Catutos, near Zapala city (Neuquén Province), has yielded the highest number of specimens, which are taxonomically and morphologically diverse. At Los Catutos locality, the Vaca Muerta Formation is represented by the Los Catutos Member, which is considered the only lithographic limestones known in the Southern Hemisphere. Here, we review the Tithonian fish faunas from the Vaca Muerta Formation. During Late Jurassic times, the actual Argentinian territory could have been a morphological diversification center, at least for some actinopterygian groups. The apparently lower species diversity recorded in marine Jurassic ichthyofaunas of Argentina (and some Gondwanan countries) in comparison with Chilean and European fish faunas could be related to the fish paleontological research history in Gondwana and the low number of detailed studies of most of specimens recorded.

  12. A new basal sauropod dinosaur from the middle Jurassic of Niger and the early evolution of sauropoda.

    Directory of Open Access Journals (Sweden)

    Kristian Remes

    2009-09-01

    Full Text Available The early evolution of sauropod dinosaurs is poorly understood because of a highly incomplete fossil record. New discoveries of Early and Middle Jurassic sauropods have a great potential to lead to a better understanding of early sauropod evolution and to reevaluate the patterns of sauropod diversification.A new sauropod from the Middle Jurassic of Niger, Spinophorosaurus nigerensis n. gen. et sp., is the most complete basal sauropod currently known. The taxon shares many anatomical characters with Middle Jurassic East Asian sauropods, while it is strongly dissimilar to Lower and Middle Jurassic South American and Indian forms. A possible explanation for this pattern is a separation of Laurasian and South Gondwanan Middle Jurassic sauropod faunas by geographic barriers. Integration of phylogenetic analyses and paleogeographic data reveals congruence between early sauropod evolution and hypotheses about Jurassic paleoclimate and phytogeography.Spinophorosaurus demonstrates that many putatively derived characters of Middle Jurassic East Asian sauropods are plesiomorphic for eusauropods, while South Gondwanan eusauropods may represent a specialized line. The anatomy of Spinophorosaurus indicates that key innovations in Jurassic sauropod evolution might have taken place in North Africa, an area close to the equator with summer-wet climate at that time. Jurassic climatic zones and phytogeography possibly controlled early sauropod diversification.

  13. Toward establishing a definitive Late-Mid Jurassic (M-series) Geomagnetic Polarity Reversal Time Scale through unraveling the nature of Jurassic Quiet Zone.

    Science.gov (United States)

    Tominaga, M.; Tivey, M.; Sager, W.

    2017-12-01

    Two major difficulties have hindered improving the accuracy of the Late-Mid Jurassic geomagnetic polarity time scale: a dearth of reliable high-resolution radiometric dates and the lack of a continuous Jurassic geomagnetic polarity time scale (GPTS) record. We present the latest effort towards establishing a definitive Mid Jurassic to Early Cretaceous (M-series) GPTS model using three high-resolution, multi-level (sea surface [0 km], mid-water [3 km], and near-source [5.2 km]) marine magnetic profiles from a seamount-free corridor adjacent to the Waghenaer Fracture Zone in the western Pacific Jurassic Quiet Zone (JQZ). The profiles show a global coherency in magnetic anomaly correlations between two mid ocean ridge systems (i.e., Japanese and Hawaiian lineations). Their unprecedented high data resolution documents a detailed anomaly character (i.e., amplitudes and wavelengths). We confirm that this magnetic anomaly record shows a coherent anomaly sequence from M29 back in time to M42 with previously suggested from the Japanese lineation in the Pigafetta Basin. Especially noticeable is the M39-M41 Low Amplitude Zone defined in the Pigafetta Bsin, which potentially defines the bounds of JQZ seafloor. We assessed the anomaly source with regard to the crustal architecture, including the effects of Cretaceous volcanism on crustal magnetization and conclude that the anomaly character faithfully represents changes in geomagnetic field intensity and polarity over time and is mostly free of any overprint of the original Jurassic magnetic remanence by later Cretaceous volcanism. We have constructed polarity block models (RMS Japanese M-series sequence. The anomalously high reversal rates during a period of apparent low field intensity suggests a unique period of geomagnetic field behavior in Earth's history.

  14. Radioactive contamination of oil produced from nuclear-broken shale

    International Nuclear Information System (INIS)

    Arnold, W.D.; Crouse, D.J.

    1970-01-01

    The results of small-scale exposure and retorting tests indicate that oil recovered from shale that has been broken with nuclear explosives will be contaminated with tritium. When oil shale was heated in sealed flasks with tritiated water vapor or with tritiated hydrogen, both the shale and the oil subsequently retorted from the shale contained tritium. There was much less contamination of the shale or oil, however, when the shale was exposed to tritiated methane and ethane. Contamination of shale and oil with tritium, as the result, of exposure to tritiated water, increased as the exposure temperature, exposure pressure, and the tritium concentration in the water were increased. This contamination also increased as the exposure time was increased up to 25 days, but not significantly thereafter. More than 90% of the tritium was removed from contaminated shale by treating the shale with moist air at elevated temperatures. Only small amounts of the tritium were removed from crude oil by contacting it with solid drying agents or with water. When tritium-contaminated shale oil was distilled, the tritium contents of the recovered fractions were found to be approximately equal. After being heated with a sample of underground test-shot debris, liquid shale oil became contaminated with radioactive fission products. Most of the radioactivity of the oil was due to finely dispersed solids rather than to dissolved radionuclides. Filtration of the oil removed a major fraction of the radioactive material. When the contaminated oil was distilled, more than 99% of the radionuclides remained in the pot residue. (author)

  15. A review on technologies for oil shale surface retort

    International Nuclear Information System (INIS)

    Pan, Y.; Zhang, X.; Liu, S.; Yang, S.A.; Ren, N.

    2012-01-01

    In recent years, with the shortage of oil resources and the continuous increase in oil prices, oil shale has seized much more attention. Oil shale is a kind of important unconventional oil and gas resources. Oil shale resources are plentiful according to the proven reserves in places. And shale oil is far richer than crude oil in the world. Technology processing can be divided into two categories: surface retorting and in-situ technology. The process and equipment of surface retorting are more mature, and are still up to now, the main way to produce shale oil from oil shale. According to the variations of the particle size, the surface retorting technologies of oil shale can be notified and classified into two categories such as lump shale process and particulate shale process. The lump shale processes introduced in this article include the Fushun retorting technology, the Kiviter technology and the Petrosix technology; the particulate processes include the Gloter technology, the LR technology, the Tosco-II technology, the ATP (Alberta Taciuk Process) technology and the Enefit-280 technology. After the thorough comparison of these technologies, we can notice that, this article aim is to show off that : the particulate process that is environmentally friendly, with its low cost and high economic returns characteristics, will be the major development trend; Combined technologies of surface retorting technology and other oil producing technology should be developed; the comprehensive utilization of oil shale should be considered during the development of surface retorting technology, meanwhile the process should be harmless to the environment. (author)

  16. Oil shale research related to proposed nuclear projects

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, H C; Sohns, H W; Dinneen, G U [Laramie Petroleum Research Center, Bureau of Mines, Department of the Interior, Laramie, WY (United States)

    1970-05-15

    The Bureau of Mines is conducting research to develop data pertinent to in situ retorting of oil shale fractured by a nuclear explosion or other means. Maximum utilization of the Green River oil shale found in Colorado, Utah, and Wyoming, at depths ranging from outcrops to several thousand feet, requires development of several methods of processing. Early research was devoted to developing processes for application to oil shale occurring at depths suitable for mining. In present research, the emphasis is on in situ retorting and recovery processes that would be more satisfactory for oil shales occurring at greater depths. Development of an in situ process depends upon finding or establishing sufficient permeability in the oil shale beds for the passage of fluids which serve as a heat carrier in bringing the oil shale to retorting temperature. Use of a nuclear explosive seems to offer the best chance for successfully fracturing the thicker and more deeply buried portions of the deposit to give the required permeability. Processing the very large quantity of broken and fractured oil shale that would be produced presents many problems which require new background data for their solution. This paper describes research the Bureau of Mines is conducting to develop pertinent data. Primarily this research involves laboratory determination of properties of oil shale, pilot scale investigation of retorting characteristics of ungraded broken shale, and underground combustion of shale fractured by pressure and chemical explosives. Application of the research results should aid in designing the oil recovery phase and provide an estimate of the quantity of oil that may be obtained in a nuclear experiment in oil shale. (author)

  17. Oil shale research related to proposed nuclear projects

    International Nuclear Information System (INIS)

    Carpenter, H.C.; Sohns, H.W.; Dinneen, G.U.

    1970-01-01

    The Bureau of Mines is conducting research to develop data pertinent to in situ retorting of oil shale fractured by a nuclear explosion or other means. Maximum utilization of the Green River oil shale found in Colorado, Utah, and Wyoming, at depths ranging from outcrops to several thousand feet, requires development of several methods of processing. Early research was devoted to developing processes for application to oil shale occurring at depths suitable for mining. In present research, the emphasis is on in situ retorting and recovery processes that would be more satisfactory for oil shales occurring at greater depths. Development of an in situ process depends upon finding or establishing sufficient permeability in the oil shale beds for the passage of fluids which serve as a heat carrier in bringing the oil shale to retorting temperature. Use of a nuclear explosive seems to offer the best chance for successfully fracturing the thicker and more deeply buried portions of the deposit to give the required permeability. Processing the very large quantity of broken and fractured oil shale that would be produced presents many problems which require new background data for their solution. This paper describes research the Bureau of Mines is conducting to develop pertinent data. Primarily this research involves laboratory determination of properties of oil shale, pilot scale investigation of retorting characteristics of ungraded broken shale, and underground combustion of shale fractured by pressure and chemical explosives. Application of the research results should aid in designing the oil recovery phase and provide an estimate of the quantity of oil that may be obtained in a nuclear experiment in oil shale. (author)

  18. Radioactive contamination of oil produced from nuclear-broken shale

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, W D; Crouse, D J

    1970-05-15

    The results of small-scale exposure and retorting tests indicate that oil recovered from shale that has been broken with nuclear explosives will be contaminated with tritium. When oil shale was heated in sealed flasks with tritiated water vapor or with tritiated hydrogen, both the shale and the oil subsequently retorted from the shale contained tritium. There was much less contamination of the shale or oil, however, when the shale was exposed to tritiated methane and ethane. Contamination of shale and oil with tritium, as the result, of exposure to tritiated water, increased as the exposure temperature, exposure pressure, and the tritium concentration in the water were increased. This contamination also increased as the exposure time was increased up to 25 days, but not significantly thereafter. More than 90% of the tritium was removed from contaminated shale by treating the shale with moist air at elevated temperatures. Only small amounts of the tritium were removed from crude oil by contacting it with solid drying agents or with water. When tritium-contaminated shale oil was distilled, the tritium contents of the recovered fractions were found to be approximately equal. After being heated with a sample of underground test-shot debris, liquid shale oil became contaminated with radioactive fission products. Most of the radioactivity of the oil was due to finely dispersed solids rather than to dissolved radionuclides. Filtration of the oil removed a major fraction of the radioactive material. When the contaminated oil was distilled, more than 99% of the radionuclides remained in the pot residue. (author)

  19. Depositional environments of the Jurassic Maghara main coal seam in north central Sinai, Egypt

    Science.gov (United States)

    Edress, Nader Ahmed Ahmed; Opluštil, Stanislav; Sýkorová, Ivana

    2018-04-01

    Twenty-eight channel samples with a cumulative thickness of about 4 m collected from three sections of the Maghara main coal seam in the middle Jurassic Safa Formation have been studied for their lithotype and maceral compositions to reconstruct the character of peat swamp, its hydrological regime and the predominating type of vegetation. Lithotype composition is a combination of dully lithotypes with duroclarain (19% of total cumulative thickness), clarodurain (15%), black durain (15%), and shaly coal (15%) and bright lithotypes represented by clarain (23%), vitrain (12%) and a small proportion of wild fire-generated fusain (1%). Maceral analyses revealed the dominance of vitrinite (70.6% on average), followed by liptinite (25.2%) and inertinite (8.1%). Mineral matter content is ∼9% on average and consists of clay, quartz and pyrite concentrate mostly at the base and the roof of the seam. Dominantly vitrinite composition of coal and extremely low fire- and oxidation-borne inertinite content, together with high Gelification Indices imply predomination of waterlogged anoxic conditions in the precursing mire with water tables mostly above the peat surface throughout most of the time during peat swamp formation. Increases in collotelinite contents and Tissue Preservation Index up the section, followed by a reversal trend in upper third of the coal section, further accompanied by a reversal trend in collodetrinite, liptodetrinite, alginite, sporinite and clay contents records a transition from dominately limnotelmatic and limnic at the lower part to dominately limnotelmatic with increase telmatic condition achieved in the middle part of coal. At the upper part of coal seam an opposite trend marks the return to limnic and limnotelmatic conditions in the final phases of peat swamp history and its subsequent inundation. The proportion of arborescent (mostly coniferous) and herbaceous vegetation varied throughout the section of the coal with tendency of increasing

  20. Lithofacies, paleoenvironment and high-resolution stratigraphy of the D5 and D6 members of the Middle Jurassic carbonates Dhruma Formation, outcrop analog, central Saudi Arabia

    Science.gov (United States)

    Yousif, Ibrahim M.; Abdullatif, Osman M.; Makkawi, Mohammad H.; Bashri, Mazin A.; Abdulghani, Waleed M.

    2018-03-01

    This study characterizes the lithofacies, paleoenvironment and stratigraphic architecture of the D5 and D6 members of carbonates Dhruma Formation outcrops in central Saudi Arabia. The study integrates detailed lithofacies analysis based on vertical and lateral profiles, in addition to thin-sections petrography to reveal the high-resolution architecture framework. Nine lithofacies types (LFTs) were defined namely: (1) skeletal peletal spiculitic wackestone (15%), (2) peloidal echinoderm packstone (19%), (3) fissile shale (36%), (4) peloidal spiculitic echinoderm pack-grainstone (5%), (5) cross-bedded peloidal skeletal oolitic grainstone (7%), (6) oolitic grainstone (2%), (7) intraformational rudstone (cycles and cycle sets with 5th to 6th orders magnitude, and thickness ranges from a few centimeters up to 6 m with an average of 1.5 m. Those are stacked to form four high-frequency sequences with thickness range from 1 m up to 14 m. The latter were grouped into a single depositional sequence of 3rd order magnitude. The architectural analysis also shows that the potential reservoir units were intensively affected by muddy-textured rocks which act as reservoir seals. These variations in the stratigraphic sequences in Middle Jurassic Dhruma Formation and its equivalents could be attributed to the eustatic sea-level changes, climate, tectonics, and local paleoenvironments. This study attempts to provide detailed insight into reservoir heterogeneity and architecture. The analog may help to understand and predict lithofacies heterogeneity, architecture, and quality in the subsurface equivalent reservoirs.

  1. Shale oil potential and thermal maturity of the Lower Toarcian Posidonia Shale in NW Europe

    NARCIS (Netherlands)

    Song, J.; Littke, R.; Weniger, P.; Ostertag-Henning, C.; Nelskamp, S.

    2015-01-01

    A suite of drilling cores and outcrop samples of the Lower Toarcian Posidonia Shale (PS) were collected from multiple locations including the Swabian Alb and Franconian Alb of Southwest-Germany, Runswick Bay of UK and Loon op Zand well (LOZ-1) of the West Netherlands Basin. In order to assess the

  2. Episodic Jurassic to Lower Cretaceous intraplate compression in Central Patagonia during Gondwana breakup

    Science.gov (United States)

    Navarrete, César; Gianni, Guido; Echaurren, Andrés; Kingler, Federico Lince; Folguera, Andrés

    2016-12-01

    From Lower Jurassic to Lower Cretaceous, several intraplate compression events affected discrete sectors of Central Patagonia, under a general context of crustal extension associated with Gondwana breakup. This was demonstrated by means of 2D and 3D seismic and borehole data, which show partial inversion of Lower and Middle Jurassic extensional structures of the Chubut and Cañadón Asfalto basins, during the earliest stages of breakup. A comparison with surrounding areas in Patagonia, where similar Jurassic intraplate compression was described, allowed the discrimination of three discrete pulses of subtle compression (C1: ∼188-185 Ma; C2: ∼170-163; C3: ∼157-136? Ma). Interestingly, episodic intraplate compressional events are closely followed by high flux magmatic events linked to the westward expansion of the Karoo-Ferrar thermal anomaly, which impacted on the lithosphere of southwest Gondwana in Lower Jurassic. In addition, we determined the approximate direction of the main compressive strain (σ1) compatible with other Jurassic intraplate belts of South America. These observations led us to propose a linkage between a thermo mechanically weakened continental crust due to LIPs activity, changes in plate motions and ridge-push forces generated by the opening of the Weddell Sea, in order to explain intraplate shortening, interrupted while Karoo LIPs magmatic invigoration took place.

  3. Palinspastic reconstruction and geological evolution of Jurassic basins in Mongolia and neighboring China

    Directory of Open Access Journals (Sweden)

    Wu Genyao

    2013-07-01

    Full Text Available The important event in Jurassic tectonics in Mongolia was the subduction and closure of the Mongolia-Okhotsk ocean; correspondingly, basin evolution can be divided into two main stages, related to the orogeny and collapse of the orogenic belt, respectively. The developing of Early–Middle Jurassic basins to the north of the ocean resulted from back-arc extension. The fossil sutures, from the China–SE Asia sub-continent to the south of the ocean, were rejuvenated by subduction-related orogeny; in addition, the Yanshanian intra-continental movement occurred. Three Early–Middle Jurassic molasse basins were developed by movement in Inner Mongolia, all of which stretched westwards (or northwards into Mongolia; therefore, the molasse basins in eastern and southern Mongolia had the same geometric and kinematic features as the basins in the Inner Mongolia. Owing to the collapse of the Mongolia-Okhotsk orogenic belt, a group of rift basins developed during the Late Jurassic. In eastern Mongolia, the NE orientated extensional basins were controlled by the neogenic NE-structure. The contemporary basins in southern Mongolia and the neighboring areas in China were constrained by remobilization (inherited activation of the latitudinal or ENE-directional basement structures. Three stages can be recognized in the evolution of the Early–Middle Jurassic basins after reversal; the basins also experienced four episodes of reformation.

  4. The Oldest Jurassic Dinosaur: A Basal Neotheropod from the Hettangian of Great Britain.

    Science.gov (United States)

    Martill, David M; Vidovic, Steven U; Howells, Cindy; Nudds, John R

    2016-01-01

    Approximately 40% of a skeleton including cranial and postcranial remains representing a new genus and species of basal neotheropod dinosaur is described. It was collected from fallen blocks from a sea cliff that exposes Late Triassic and Early Jurassic marine and quasi marine strata on the south Wales coast near the city of Cardiff. Matrix comparisons indicate that the specimen is from the lithological Jurassic part of the sequence, below the first occurrence of the index ammonite Psiloceras planorbis and above the last occurrence of the Rhaetian conodont Chirodella verecunda. Associated fauna of echinoderms and bivalves indicate that the specimen had drifted out to sea, presumably from the nearby Welsh Massif and associated islands (St David's Archipelago). Its occurrence close to the base of the Blue Lias Formation (Lower Jurassic, Hettangian) makes it the oldest known Jurassic dinosaur and it represents the first dinosaur skeleton from the Jurassic of Wales. A cladistic analysis indicates basal neotheropodan affinities, but the specimen retains plesiomorphic characters which it shares with Tawa and Daemonosaurus.

  5. Marine shale and the Hazwaste recycling debate

    International Nuclear Information System (INIS)

    Bishop, J.

    1988-01-01

    This paper reports that Marine Shale Processors, Inc. (St. Rose, La.), and the Hazardous Waste Treatment Council (Washington, D.C.), an industry trade association, are at the focus of a controversy whose resolution has significant implications for the respective definitions, concepts and legal statuses of hazardous-waste incineration and recycling. Marine Shale Processors (MSP) claims it recycles hazardous wastes from a variety of government and commercial sources by blending it and treating it thermally in a large rotary kiln to produce non-hazardous aggregate material, which is sold for construction, road-building or other purposes. The Hazardous Waste Treatment Council (HWTC) and others allege that, under the provisions of the Resource Conservation and Recovery Act (RCRA), MSP is operating an unpermitted hazardous-waste incinerator. According to HWTC officials, MSP's identification as a recycler is inappropriate and has allowed the company unfairly to avoid permitting costs and formal compliance with RCRA standards and regulations. Recently, the Louisiana legislature passed laws declaring that hazardous-waste recyclers in the state must meet the same standards as permitted hazardous-waste incinerators. At press time, a hearing before the Louisiana Department of Environmental Quality to determine MSP's status as a recycler under the new laws was set for Sept. 29. Since all parties in the debate over Marine Shale's industry role appear to agree that the controversy is central to the emerging issue of establishing clear distinctions between recycling and hazardous-waste destruction, this article describes the arguments on both sides as these stood in mid-September

  6. Utica Shale Energy and Environment Laboratory (USEEL)

    Science.gov (United States)

    Cole, D. R.

    2017-12-01

    Despite the rapid growth of the UOG industry in the Appalachian Basin of Pennsylvania and neighboring states, there are still fundamental concerns regarding the environmentally sound and cost efficient extraction of this unique asset. To address these concerns, Ohio State University has established the Department of Energy-funded Utica Shale Energy and Environment Laboratory, a dedicated research program where scientists from the university will work with the U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL), academia, industry, and regulatory partners, to measure and monitor reservoir response to UOG development and any associated environmental concerns. The USEEL site will be located in Greene County, Pennsylvania, in the heart of the deep Utica-Pt. Pleasant Shale play of the Appalachian Basin. The USEEL project team will characterize and quantify the gas-producing attributes of one of the deepest portions of the Utica-Pt. Pleasant formations in the Appalachian Basin via a multi-disciplinary collaboration that leverages state-of-the-art capabilities in geochemistry, core assessment, well design and logging, 3-D and micro-seismic, DTS and DAS fiber optics, and reservoir modelling. Fracture and rock strength analyses will be complemented by a comprehensive suite of geophysical and geochemical logs, water and chip samples, and cores (pressure sidewall and whole core) to evaluate fluids, mineral alteration, microbes, pore structure, and hydrocarbon formation and alteration in the shale pore space. Located on an existing Marcellus drill pads in southwestern Pennsylvania, USEEL will provide an unprecedented opportunity to evaluate the economic and environmental effects of Marcellus pad expansion on the integrity of near-by existing production wells, ground disruption and slope stability, and ultimate efforts to conduct site reclamation. Combined with the overall goal of an improved understanding of the Utica-Pt. Pleasant system, USEEL

  7. Shale gas wastewater management under uncertainty.

    Science.gov (United States)

    Zhang, Xiaodong; Sun, Alexander Y; Duncan, Ian J

    2016-01-01

    This work presents an optimization framework for evaluating different wastewater treatment/disposal options for water management during hydraulic fracturing (HF) operations. This framework takes into account both cost-effectiveness and system uncertainty. HF has enabled rapid development of shale gas resources. However, wastewater management has been one of the most contentious and widely publicized issues in shale gas production. The flowback and produced water (known as FP water) generated by HF may pose a serious risk to the surrounding environment and public health because this wastewater usually contains many toxic chemicals and high levels of total dissolved solids (TDS). Various treatment/disposal options are available for FP water management, such as underground injection, hazardous wastewater treatment plants, and/or reuse. In order to cost-effectively plan FP water management practices, including allocating FP water to different options and planning treatment facility capacity expansion, an optimization model named UO-FPW is developed in this study. The UO-FPW model can handle the uncertain information expressed in the form of fuzzy membership functions and probability density functions in the modeling parameters. The UO-FPW model is applied to a representative hypothetical case study to demonstrate its applicability in practice. The modeling results reflect the tradeoffs between economic objective (i.e., minimizing total-system cost) and system reliability (i.e., risk of violating fuzzy and/or random constraints, and meeting FP water treatment/disposal requirements). Using the developed optimization model, decision makers can make and adjust appropriate FP water management strategies through refining the values of feasibility degrees for fuzzy constraints and the probability levels for random constraints if the solutions are not satisfactory. The optimization model can be easily integrated into decision support systems for shale oil/gas lifecycle

  8. Gas production in the Barnett Shale obeys a simple scaling theory.

    Science.gov (United States)

    Patzek, Tad W; Male, Frank; Marder, Michael

    2013-12-03

    Natural gas from tight shale formations will provide the United States with a major source of energy over the next several decades. Estimates of gas production from these formations have mainly relied on formulas designed for wells with a different geometry. We consider the simplest model of gas production consistent with the basic physics and geometry of the extraction process. In principle, solutions of the model depend upon many parameters, but in practice and within a given gas field, all but two can be fixed at typical values, leading to a nonlinear diffusion problem we solve exactly with a scaling curve. The scaling curve production rate declines as 1 over the square root of time early on, and it later declines exponentially. This simple model provides a surprisingly accurate description of gas extraction from 8,294 wells in the United States' oldest shale play, the Barnett Shale. There is good agreement with the scaling theory for 2,057 horizonta