Uranium, thorium, and potassium in black shales of the Bazhenov Formation of the West Siberian marine basin

The Infra-Getic Unit is a palaeogeographic unit, predestined by palaeotectonics. From the point of view of geological heritage, it represents a geosites framework. For the purpose of the correlation, the Serbian sections of Lukanja, Bogorodica Monastery, Rosomac and Senokos, as well as the Bulgarian sections of Komshtitsa, Gintsi, and Stanyantsi were used. The Jurassic sediments of the Infra-Getic Unit crop out on the southern slops of the Stara Planina Mountain in east Serbia and west Bulgaria. The Lower Jurassic started with continental and continental-marine sediments (clays and sandstones) (Lukanja clastics and Lukanja coal beds in Serbia and the Tuden Formation in Bulgaria) and continue with Lukanja quartz sandstones (Serbia) and the Kostina Formation (Bulgaria). These sediments are covered by Lukanja brachiopod beds and Lukanja limestones (Serbia) and the Romanov Dol, Ravna and Dolni Loukovit Members of the Ozirovo Formation (Bulgaria) predominantly consist of bioclastic limestones. The sedimentations follow with Lukanja belemnites-gryphaea beds (marls and clayey limestones), which in Bulgaria correspond to the Bukorovtsi Member (also marls and clayey limestones) of the Ozirovo Formation. The Middle Jurassic sedimentation started with black shales with Bossitra alpine. These sediments are individualized in Serbia as Senokos aleurolites and clays and in Bulgaria they are known as the Etropole Formation. In Serbia the section continues with sandstones called Vodenicki sandstones of Bajocian age, known in Bulgaria as the Dobrogled Member of the Polaten Formation. However, in Bulgaria, the age is Upper Bajocian-Lower Bathonian, and it cover the marls of the lower member (Gornobelotintsi Member) of the Bov Formation and is covered by the upper member - alternation of marls and clayey limestones - the Verenitsa Member of the Bov Formation. The Vodenicki sandstones-Dobrogled Member which ended their distribution in the section of Komshtitsa, to the east (in the Gintsi section), they are not represented - build a body of sandstones, a prodelta coming from the west to the east. The Bov Formation corresponds to the Senokos ammonite beds in east Serbia. The upper boundary of the Senokos ammonite beds and of the Bov Formation is sharp. It is covered by grey limestones of the Yavorec Formation in Bulgaria and by the Kamenica limestones in eastern Serbia. They are covered by grey or red nodular/lithoclastic limestones ("ammonitico rosso" type) of the Gintsi Formation in Bulgaria and the Pokrovenik ammonitic (acanthicum) limestones in Serbia. The Jurassic section in the Infra-Getic ended with grey micritic and lithoclastic limestones, which belong to the Rosomac and Rsovci limestones in east Serbia and to the Glozhene Formation in Bulgaria.

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Highly Metalliferous Potential of Framboidal and Nodular Pyrite Varieties from the Oil-Bearing Jurassic Bazhenov Formation, Western Siberia

Minerals ◽

10.3390/min10050449 ◽

2020 ◽

Vol 10 (5) ◽

pp. 449

Author(s):

Kirill S. Ivanov ◽

Valery V. Maslennikov ◽

Dmitry A. Artemyev ◽

Aleksandr S. Tseluiko

Keyword(s):

Oil And Gas ◽

Massive Sulfide ◽

Global Scale ◽

Ore Deposits ◽

Black Shales ◽

Ural Mountains ◽

Sulfide Deposits ◽

Bazhenov Formation ◽

Zn And Cu In ◽

Positive Correlations

In the Bazhenov Formation, framboidal clusters and nodular pyrite formed in the dysoxic–anoxic interface within organic-rich sediments. Some nodule-like pyritized bituminous layers and pyrite nodules are similar to pyritized microbial mat fragments by the typical fine laminated structure. Framboidal pyrite of the Bazhenov Formation is enriched in redox-sensitive elements such as Mo, V, Au, Cu, Pb, Ag, Ni, Se, and Zn in comparison with the host shales and nodular pyrite. Nodular pyrite has higher concentrations of As and Sb, only. Strong positive correlations that can be interpreted as nano-inclusions of organic matter (Mo, V, Au), sphalerite (Zn, Cd, Hg, Sn, In, Ga, Ge), galena (Pb, Bi, Sb, Te, Ag, Tl), chalcopyrite (Cu, Se) and tennantite (Cu, As, Sb, Bi, Te, Ag, Tl) and/or the substitution of Co, Ni, As and Sb into the pyrite. On the global scale, pyrite of the Bazhenov Formation is very similar to pyrite from highly metalliferous bituminous black shales, associated, as a rule, with gas and oil-and-gas deposits. Enrichment with Mo and lower Co and heavy metals indicate a higher influence of seawater during formation of pyrite from the Bazhenov Formation in comparison to different styles of ore deposits. Transitional elements such as Zn and Cu in pyrite of the Bazhenov Formation has resulted from either a unique combination of the erosion of Cu–Zn massive sulfide deposits of the Ural Mountains from one side and the simultaneous manifestation of organic-rich gas seep activity in the West Siberian Sea from another direction.

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IV.—The Upper Trias of Leicestershire

Geological Magazine ◽

10.1017/s0016756800126226 ◽

1913 ◽

Vol 10 (5) ◽

pp. 205-215 ◽

Cited By ~ 1

Author(s):

A. R. Horwood

Keyword(s):

Black Shales ◽

The South ◽

The West ◽

West Side ◽

North West ◽

The North ◽

Eastern Boundary ◽

East End

Although the Rhætic beds are not exposed continuously along the eastern boundary of the Keuper outcrop, they have been proved at many points from the River Trent in the north on the Nottinghamshire border to Glen Parva in the south. South of this point there is so much drift, and borings within the Liassic outcrop have been so isolated or shallow, that there is a gap in our knowledge of the intervening ground between the last point and the Rugby district. The Countesthorpe boring, carried to a depth of over 600 feet, encountered Upper Keuper beneath the Drift, with no intervening Rhætics. Commencing in the north in the Gotham district the two outliers are capped above the Red Marl and Tea-green Marl with Rhætic beds, and Lower Lias Limestone (Ps. planorbe zone) above. At Ash Spinney at the south end of the southern outlier, and at the east end of Crownend Wood, Black Shales with Avicula contorta crop out; and on the west side septaria are seen. On the north-west side of the northern outlier at Cottager's Hill Protocardium phillipianum has been found in a well-section near the lane. Rhætic shales are seen in the shafts driven for gypsum works about Gotham.

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The Structure of the Edale, Mam Tor and Castleton Area

Geological Magazine ◽

10.1017/s0016756800073714 ◽

1942 ◽

Vol 79 (3) ◽

pp. 188-196 ◽

Cited By ~ 2

Author(s):

O. T. Jones

Keyword(s):

Black Shales ◽

The West ◽

North West ◽

East And West ◽

The Village ◽

North And South ◽

River Derwent

Edale lies in the valley of the River Noe about 3 miles north-west of Castleton. Near Edale End, about 2½ miles below the village, the Noe turns from a nearly east and west course to a nearly north and south course past Hope to join the River Derwent. In the neighbourhood of Edale the floor and lower flanks of the valley are formed of black shales known as the Edale Shales; they are overlain in succession by the Mam Tor Sandstones, the Shale Grit, the Grindslow Shales, and the coarse Kinder Scout Grits which form the great plateau of the Peak and the precipitous edge of Kinder Scout. North of the Edale valley the Mam Tor Sandstones reappear below the Shale Grit in Ashop Dale and Alport Dale. They occur also to the west of the valley in two narrow inliers just north of the railway in Roych Clough and Moor Clough.

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Types of reservoirs in the Bazhenov formation

Недропользование. Горное дело. Направления и технологии поиска, разведки и разработки месторождений полезных ископаемых. Экономика. Геоэкология: Материалы XVI международной конференции (20-24 апреля 2020, Новосибирск) ◽

10.18303/b978-5-4262-0102-6-2020-019 ◽

2020 ◽

Author(s):

Elena V. Ponomareva ◽

◽

Svetlana V. Ryzhkova ◽

Keyword(s):

Sedimentary Basin ◽

The West ◽

Bazhenov Formation

The paper considers three types of reservoirs in the Bazhenov formation: fractured, fractured-cavernous, and fractured-porous. Analysis of modern ideas about the Bazhenov Formation lithology and results of the formation testing in the southeastern and southern parts of the West Siberian sedimentary basin allowed to conclude that productive horizon Yu0 is confined to a reservoir of mainly fractured-porous type within the Koltogor-Nyrolka trench and adjacent positive tectonic elements.

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The Southern Uplands Terrane: a stratigraphical review

Earth and Environmental Science Transactions of the Royal Society of Edinburgh ◽

10.1017/s0263593300008233 ◽

2000 ◽

Vol 91 (3-4) ◽

pp. 349-362 ◽

Cited By ~ 27

Author(s):

James D. Floyd

Keyword(s):

Black Shales ◽

Biogenic Carbonate ◽

Oceanic Sediments ◽

Marine Basin

ABSTRACTThe Southern Uplands is a major Ordovician-Silurian accretionary terrane which developed as a marine basin over a period of c.75 Ma (495-420 Ma). The terrane extends to c. 10,000 km2 in Scotland alone and correlates with the similar-scale Longford–Down terrane in Ireland. Despite tectonic complexity, a detailed lithostratigraphy has been erected. The oldest strata are mudstones, cherts and lavas of mid-Arenig age known only in the Leadhills Imbricate Zone. The next youngest rocks are of similar lithology but of late Llanvirn-early Caradoc age. These oceanic sediments are succeeded by black shales of the Moffat Shale Group which are, in turn, diachronously overlain by huge volumes of turbiditic sandstones, siltstones, mudstones and minor conglomerates (greywackes) of Caradoc to Wenlock age. Overall, the terrane is sandstone-dominated, with other components such as lavas, volcaniclastics and cherts representing only a tiny proportion of the total volume. The conglomerates have a broadly northerly provenance, whereas the sandstones exhibit both marginal (NW and SE), and axial (NE and SW) derivation. During the Ordovician, strongly contrasting sources alternated through time. The youngest sandstones (Hawick and Riccarton groups), are notably rich in detrital biogenic carbonate, a rare component in the Leadhills Supergroup and Gala Group.

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