Black shales. 1. Introduction. Black shale is a widely used general term ...

Black Shale Standard. Equivalent expectations of the gamma-ray log res

black shale, also called Carboniferous Shale, variety of shale that contains abundant organic matter, pyrite, and sometimes carbonate nodules or layers and, in some locations, concentrations of copper, nickel, uranium, and vanadium. Fossils are rare in the shale and either are replaced by pyrite or are preserved as a film of graphite. Black shales occur in thin beds in many areas at various ...3.1 Mineral composition in shale. The following minerals were identified in the shales: quartz, feldspar, calcite, dolomite, illite, pyrite, chlorite, and apatite (Table 2, Fig. 1).Quartz and calcite were detected in all the samples (Fig. 1).Figures 2 and 3 show XRD distribution patterns and SEM-EDS images of the minerals in the shales. The amount of quartz in all the shale samples except ...The Wufeng Formation-Longmaxi Formation (O3w-S1l1) black shales within the Yangtze foreland basin (South China) hold significant potential as unconventional oil and gas resources. However, several challenges, including sluggish sedimentation rates, thin sedimentary layers, and notable homogeneity, hinder a comprehensive grasp of the organic matter enrichment (OME) mechanism within these shales.The black shales are composed of quartz, illite, kaolinite and traces of pyrite in some samples. Al 2 O 3 /TiO 2 ratios in the coals (6–62) and black shales (16–34) suggest a mixture of felsic and intermediate igneous rocks as sources for their detrital fractions, which is supported by the Zr-Ti binary plot.Several outcrops of black shales from the Triassic turbidite sequences of the Semanggol and Semantan formations have been described and logged (Table 1 & Fig. 3). Black shales in the Semanggol Formation occur as thin-to medium-bedded, finely-laminated dark grey to grey shales up to 15 m thick (Fig. 4 A-D). On the other hand, black shales of ...Black shales deposited in transitional environments such as tidal and deltaic environments have high terrigenous OM input. The pore structure characteristics of bulk OM in these transitional shales should have intermediate values between oil-prone OM (Fig. 19) in shales and terrigenous OM in coals at a specific maturity. Therefore, the ...Semantic Scholar extracted view of "Late Barremian / Early Aptian Re-Os age of the Ipubi Formation black shales: Stratigraphic and paleoenvironmental implications for Araripe Basin, northeastern Brazil" by Thales Lúcio et al.The chemistry of Pennsylvanian-age shales has long been of interest to geologists and geochemists. Pennsylvanian-age shales in the midcontinental United States, which vary in color from light gray to pitch black, are present in a thin layer averaging 70-cm thickness over an area of {approximately}600 000 km{sup 2}.Black shale and coal Clarke values are the average trace element contents in the World black shales and coals. These calculations are made in Russian geochemistry but up to now are poorly known in ...Most recently, Kennedy et al. (2002), based on a study of two black shale locations of Cretaceous age, suggested that organic carbon (C org) absorption onto clay mineral surfaces is a major controlling factor in its burial and preservation. Peucker-Ehrenbrink and Hannigan (2000) and Jaffe et al. (2002) investigated mobility of platinum group ...Several outcrops of black shales from the Triassic turbidite sequences of the Semanggol and Semantan formations have been described and logged (Table 1 & Fig. 3). Black shales in the Semanggol Formation occur as thin-to medium-bedded, finely-laminated dark grey to grey shales up to 15 m thick (Fig. 4 A-D). On the other hand, black shales of ...The Barnett Shale, Marcellus Shale, Haynesville Shale, Fayetteville Shale, and other gas-producing rocks are all dark gray or black shales that yield natural gas. The Bakken Shale of North Dakota and the Eagle Ford Shale of Texas are examples of shales that yield oil.ing thread in studies of black shales and is an ongoing pur-suit (Schieber et al. 2021, Schieber and Wilson 2021, this Fig. 1 Stratigraphic context of the three Devonian black shale successions examined for this study. a Bakken Shale, b New Albany Shale, c Gen-eseo Shale. Red arrows show stratigraphic position of agrichnia bearing black shalesuraniferous black shales; in some black shales, phosphatic nodules and layers with 0.02 to 0.1 percent uranium contain much of the uranium in the shale, but in other uraniferous black shales the nodules contain only 0.001 to 0.003 percent uranium. The biogenic phosphate that settles into a rela­Black shales are mixtures of terrigenous, biogenous, and hydrogenous sediment in which organic matter constitutes at least 0.5% of the material. Shales are the end product of the processes that ...Lacustrine black shales are widely developed within the Late Cretaceous Nenjiang Formation (k 2 n) of the Songliao Basin. These black shales provide an ideal natural laboratory for reconstructing the paleoclimate and paleoenvironment during the Late Cretaceous in Northeast China and have great significance in the exploration for …Some important shale reservoirs with the potential for CO 2 storage around the world are Western Canadian Sedimentary Basins [52], Dutch shale resources [53], Devonian black shales of Eastern ...Abstract. Black shales are sedimentary rocks containing >0.5% of organic carbon. They host polymetallic deposits which have been mined for Cu, Ni, Zn, Mn, P, Mo, V, U, Au and PGE (platinum group elements). Even sub-economic occurrences provide potential risk of acid rock drainage when exposed to oxic surface environment.Black shales are organic-rich, fine-grained strata deposited under oxygen-poor bottom waters which typically accumulate in deep-water, basinal locations (Demaison and Moore, 1980, Wignall and Maynard, 1993). However, thin examples often occur in more marginal locations, particularly within transgressive sedimentary records.The black shales are composed of quartz, illite, kaolinite and traces of pyrite in some samples. Al 2 O 3 /TiO 2 ratios in the coals (6-62) and black shales (16-34) suggest a mixture of felsic and intermediate igneous rocks as sources for their detrital fractions, which is supported by the Zr-Ti binary plot. V/(V+Ni) ratios average between ...'Black shales' is an old term for argillaceous rocks rich in organic matter. The characteristics of the depositional environment of such deposits have long intrigued geologists, particularly the extent to which actualistic models can be applied. The revived interest in the last few years stems principally from the wide-spread recognition ...Black shale statistics, Hole 53OA, Angola Basin. Core. 86. 87. 88. 89. 90. 91. 92. 93.Black shales are sedimentary rocks containing >0.5% of organic carbon. They host polymetallic deposits which have been mined for Cu, Ni, Zn, Mn, P, Mo, V, U, …This study uses the marine-continental transitional black shale of the Shanxi Formation in the Ordos Basin as its primary research subject. Using LT-N 2 A and LP-CO 2 A experiments, as well as FE-SEM, XRD, and associated geochemical experiments, the pore structure of the transitional shales of the Shanxi Formation is described qualitatively ...This set of black shale is widely distributed in the Yangtze Block of China, which was linked with the global transgression and cold-arid climate. The organic matter accumulation of Niutitang Formation is ultimately controlled by high productivity and favorable anoxic preservation condition. 6. ConclusionsRegional correlations of the black shales in New York show very similar field relations to those found by Conant and Swanson (1961). Close examination of these black shales reveals a number of features that indicate reworking and bedload sediment transport by waves and currents consistent with a shallow-marine inter - pretation.teristics of black shales deposited in those environments (Ta-ble 1). The resulting models represent a comprehensive and dynamic view of ancient environments of black shale accu-mulation; therefore, they are more useful in the interpretation of black shales than the existing three models in isolation. 2 Plate tectonics and exogenic processesOil shale is just one unconventional oil source that's being researched. Learn how oil shale could save the day when — and if — we hit peak oil in the U.S. Advertisement Pe­ople who owe money have a way of turning the table on their credito...Biomarkers in the black shale change regularly, and have an obvious "inflection point" at the depth of 2753-2777 m in the Chang 7 3 Sub-member, indicating that the input of terrigenous organic matter increased. However, there is a negative drift about 2% of organic carbon isotopic composition near the "inflection point", which is in ...Following Ireviken black shale deposition, conditions once again became oxygen deficient with the development of a euxinic zone in the water column. The Aeronian to Sheinwoodian deep-water redox ...The results show that in addition to the ca. 1,380 Ma LIP activity that is coeval with black shales, other major LIPs during this period can preliminarily be divided into several stages and are ...Ordovician-Silurian organic-rich shale successions of the Upper Yangtze Platform consist of the Upper Ordovician Wufeng Formation, Guanyinqiao Formation, and Lower Silurian Longmaxi Formation (Su et al., 2009).The Wufeng Formation with a thickness of tens of meters is characterized by black chert, and carbonaceous shale and mudrock containing radiolaria and graptolites (Chen et al., 2000, 2006).Black shale, channel sample 0.4 ft thick. Black shale, channel sample 0.5 ft thick. Black shale, channel sample 0.4 ft thick. Do. Black shale, channel sample 1.4 ft thick. Phosphatic nodules, weathered; from whole exposure. Channel sample, 1 ft of black brittle shale; location in formation unknown; near base of about 15 ft expo­ sure.This fine-grained shale facies is dark grey to black in colour (Fig. 2 a).With respect to the bedding, the outcrops of these facies are very thin-bedded to thinly laminated and fissile in some parts while medium to massive in other areas (Fig. 2 a).The shales are highly fractured at some outcrop locations, possibly due to the composition, high fine sand/silt content, or tectonic activities.When looked at more closely, the black shales have a laminated character (Fig. 3b) of the kind that one may see in many other laminated black shales in the rock record (O'Brien and Slatt 1990). These black shales showed discontinuous streaks of silt, and led to the term "silt-streaked black shales" when describing these rocks in drill core.Molybdenum, Bi, and Te are commonly enriched along with Au, As, and Sb in organic matter and in diagenetic pyrite in black shales (e.g., Large et al. 2007Large et al. , 2011 Gregory et al. 2015 ...Black shale oxidation not only is geological significant in altering the Earth’s surface, but also is a critical stage in geochemical elemental recycling 1,2,3,4,5,6,7,8.The …The δ 15 N values of black shales compiled in Table 5 are consistently lower than the +5‰ that is typical of modern marine organic matter [Altabet and Francois, 1994] and that are found in Pleistocene sediments deposited under the Benguela Current Upwelling System [Robinson et al., 2002] and in the Monterey Formation …A suite of black shales interbedded with thin-bedded cherts occurs at the basal Cambrian in the Northern Tarim Basin (Fig. 2), which is called black rock series in Chinese literature (Li and Gao, 1996a, Li and Gao, 1996b, Li and Gao, 2000).The two studied sections are located at Xiaoerbulake, approximately 60 km away from the Akesu City, and at Sugaitebulake, approximately 50 km away from ...The black shales of the deeper sites correlate with pink to gray fissile marls in the shallowest section. In the two remaining sections, this stratigraphic interval is missing. A relative sea ...Black shales provides the first comprehensive synthesis of the diverse research regarding the origin of petroleum source rocks. The book offers in-depth reviews from the fields sedimentology, palaeoecology, and geochemistry, and particularly focuses on the influence of palaeo-oxygen levels. Current debates--including the one over the influence of sedimentation rate, productivity, and enhanced ...black shales suggest that they were derived from rocks of intermediate to felsic composition and. from recycled sediments. The likely provenance region was the Paleoproterozoic igneous and.Banded iron formations (BIF) are predominantly Precambrian sedimentary rocks composed of alternating layers of iron-rich minerals (commonly hematite and magnetite, but also siderite, chlorite, and grunerite) and silica-rich minerals (e.g., quartz or chert) in which the Fe content of the entire rock is at least 15 wt. %. Although typically thought of as strictly Fe resources, such as in the ...The presence of thick (∼. 200 m) carbonaceous shales of Cretaceous age in the deep waters of the eastern Equatorial Atlantic was first revealed by drilling at DSDP sites 367 and 368 near the Cape Verde Islands.. More recent seismic investigations show that black shales are widely distributed in this region. In the Gambia Basin they are associated with a group of seismic reflectors lying at ...When black shales are weighted by preserved thickness, a time series (Isley and Abbott, 1999) shows three peaks in the Paleoproterozoic (i.e. ∼2.0, 1.85, and 1.7 Ga), with small peaks at 600 Ma and 1.45 Ga, ̄ and a maximum near the Archean/Proterozoic boundary between 2.7 and 2.5 Ga (Fig. 2).Plotted as a time series weighted by errors in …The Okchon black shale in Korea provides an important example of natural geological materials containing toxic elements; the Chung-Joo, Duk-Pyung, Geum-Kwan, I-Won and Chu-Bu areas are underlain ...The Xiaotan section, situated on the southwestern Yangtze Platform, South China, contains an unusually expanded sedimentary record, spanning the upper Neoproterozoic to the Cambrian and representing more than 40 My of marine sedimentation.Three distinct black shale units of the Shiyantou and Yuanshan formations were analysed for redox-sensitive trace elements and iron speciation, in order to ...January 1, 1983 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 black shales below and above show relatively lower Fe T /Al ratios, reflecting the same range as sediments from the Black Sea, which is the largest modern anoxic ocean basin (Severmann et al., 2008). Table 1.Black shales deposited in transitional environments such as tidal and deltaic environments have high terrigenous OM input. The pore structure characteristics of bulk OM in these transitional shales should have intermediate values between oil-prone OM (Fig. 19) in shales and terrigenous OM in coals at a specific maturity. Therefore, the ...Organic-rich black shales were widely accumulated on the early Cambrian Yangtze Platform (i.e., the Niutitang Formation and its equivalents), providing us a unique window to assess the influence ...3.1 Mineral composition in shale. The following minerals were identified in the shales: quartz, feldspar, calcite, dolomite, illite, pyrite, chlorite, and apatite (Table 2, Fig. 1).Quartz and calcite were detected in all the samples (Fig. 1).Figures 2 and 3 show XRD distribution patterns and SEM-EDS images of the minerals in the shales. The amount of quartz in all the shale samples except ...The effects of black shale bleaching observed in this study are important for other OM-bearing rocks because the internal rock surface area of black shales is formed predominantly by the OM surface surfaces. For example, a Silurian black shale, containing ∼10 wt% TOC has an internal surface area of 31 ± 7 × 10 6 m 2 /m 3 (Fig. 11).A global compilation of Mo isotope data from black shales indicates that the Mo isotopic variations have a consistent temporal trend, reflecting the oxygen evolution of the oceans. Relatively light δ 98/95 Mo values of the Lower Cambrian black shales compared to those of modern euxinic sediments are indicative of more widespread …... black shales deposited at depths of about 500-1500 m on seamounts, Monteiro et al. (2012) have suggested that at least 50 vol% of the ocean was anoxic at ...Permian black shales from the lower Ecca Group of the southern main Karoo Basin (MKB) have a total organic carbon (TOC) of up to ~5 wt% and have been considered primary targets for a potential ...Abstract. Ordovician black shales have been investigated extensively for at least three basic reasons: (1) they bear one of the system's most useful biostratigraphic tools, graptolites; (2) many ...Black shales are high organic matter-rich dark coloured mudstones those are often deposited during ‘oceanic anoxia events’. Most of the black shale horizons are rich in arsenic far above their average crustal abundance and are susceptible to weathering eventually leaching high As contents to the surrounding environment causing As enrichment in soil and water which adversely affect the ...A suite of black shales interbedded with thin-bedded cherts occurs at the basal Cambrian in the Northern Tarim Basin (Fig. 2), which is called black rock series in Chinese literature (Li and Gao, 1996a, Li and Gao, 1996b, Li and Gao, 2000).The two studied sections are located at Xiaoerbulake, approximately 60 km away from the Akesu …Black shales are known to contain high concentrations of trace elements in addition to their high organic carbon contents (Vine and Tourtelot, 1970). Natural weathering of black shales liberate trace elements at varying rates, including many that could pose threats to human and environmental health. The increased use of hydrofracturing for ...1. Introduction. Llandovery strata are widely distributed on the Yangtze Platform of South China. The lower part is dominated by graptolite-bearing shales, mudstones and siltstones, and was assigned to the Lungmachi Formation on the Upper and Middle Yangtze Platform (Fan et al., 2011).The Lungmachi Formation is composed generally of two parts, the lower part consisting of black shales and the ...Duwi black shales contain considerable concentrations of redox sensitive metals (e.g. V, U, Mo, Ni) and other economic elements (Cu, Pb, Zn). The enrichment of black shale with Zn, V, Cu and Cr ...Black shale is widely distributed on the northern Yangtze platform, where advanced weathering is present due to the favourable exposure and a humid climate (Ling et al., 2015, 2016). To understand elemental behaviors within the context of catchment-scale weathering, examining vertical weathering profiles is an important approach. ...Black shales are sedimentary rocks containing > 0.5% of organic carbon. They host polymetallic deposits which have been mined for Cu, Ni, Zn, Mn, P, Mo, V, U, Au and PGE (platinum group elements).Oil Shale Extraction - Oil shale extraction is more complicated than crude oil extraction; it includes the extra steps of retorting and refining. Read about oil shale extraction. Advertisement The process of extracting liquid crude oil from...Black shales in the Semanggol Formation occur as thin-to medium-bedded, finely-laminated dark grey to grey shales up to 15 m thick (Fig. 4A-D). On the other hand, black shales of the Semantan Formation always occur in contact with volcaniclastic sediments. Shale intervals are relatively thick in all outcrops reaching 20 m and areBlack shales are sedimentary rocks containing > 0.5% of organic carbon. They host polymetallic deposits which have been mined for Cu, Ni, Zn, Mn, P, Mo, V, U, Au and PGE (platinum group elements).Early Cambrian black shales display strongly enriched Se, Ga, and As, significantly enriched Ba, Bi, and Rb, weakly enriched Mo, Cs, Cd, V, U, Be, In, and Tl, normal Sc, Th, Cr, Li, Cu, Ni, and Pb and depleted Co, Zn, and Sr. Moreover, Se is the most enriched trace element in the Ediacaran and early Cambrian black shales: concentrations vary ...The Xiaotan section, situated on the southwestern Yangtze Platform, South China, contains an unusually expanded sedimentary record, spanning the upper Neoproterozoic to the Cambrian and representing more than 40 My of marine sedimentation.Three distinct black shale units of the Shiyantou and Yuanshan formations were analysed for redox-sensitive trace elements and iron speciation, in order to ...Black shales are organic-rich, fine-grained strata deposited under oxygen-poor bottom waters which typically accumulate in deep-water, basinal locations (Demaison and Moore, 1980, Wignall and Maynard, 1993). However, thin examples often occur in more marginal locations, particularly within transgressive sedimentary records. ...Black shales are widespread at the Precambrian/Cambrian transition and document a global ocean anoxic event, which is part of major environmental and biological changes, such as plate tectonic reconfiguration, mass extinction, and accelerated diversification of metazoans (Kimura and Watanabe, 2001, Steiner et al., 2001).The …. Lacustrine black shales are widely develBlack shales were deposited in the continental margin rifts We present δ60Ni values for black shales, determined by double-spike MC-ICP-MS. The samples comprise Paleoproterozoic Talvivaara Ni–Zn–Co–Cu black shales from Finland, Neoproterozoic black shales from the Teplá-Barrandian Unit, Czech Republic, Early Cambrian Ni–Mo-rich black shales from the Yangtze Craton, and Devonian Ni–Zn–PGE black shales from Yukon, Canada. In addition, the ... Black shales are increasingly investigated Shale is the most common sedimentary rock, accounting for about 70 percent of the rock in the Earth's crust. Shale is a fine-grained rock made from compacted mud and clay. The defining characteristic of shale is its ability to break into layers or fissility. Black and gray shale are common, but the rock can occur in any color.Black shales occur in a pivotal part of the classic Kansas cyclothem originally described by Moore (1936) and designated the core shale by Heckel (1977).The terminology differentiates this shale from other shales in the cyclothem, particularly the thicker nonmarine shales that separate the marine bundles of units that compose the majority of the cyclothems. Black shale statistics, Hole 53OA, Angola Basin. Core. 86. 87. 88. 89....

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