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Bolonin A.V.,RAS Institute of Geology and Mineralogy | Gradovsky I.F.,Russian State Geological Prospecting University
Geology of Ore Deposits | Year: 2012

The Ordovician-Lower Carboniferous sequence of slightly metamorphosed gray carbonate-terrigenous rocks contains the Silurian black cherty shales enriched in carbon (6-9%), pyrite (6-7%), and uranium (~30 ppm). The uranium ore is localized at the pinch-out of areal and linear zones of the Early Permian supergene (exogenic) oxidation of rocks expressed in reddening (hematitization). U, As, Sb, Cu, Ni, Mo, and Ag have been removed from the oxidized black shales and concentrated in the cementation zone in form of pitchblende and sulfides in wall-rock disseminations and veinlets largely hosted in carbonate-bearing rocks. In the Late Permian, during deposition of the upper Rotliegende and Zechstein, the fractures in the basement were filled with carbonates and sulfates; uranium was partly redeposited along with enrichment in Pb and Zn. Mesozoic and Cenozoic supergene processes altered uranium ore insignificantly. © 2012 Pleiades Publishing, Ltd.

d'Almeida G.A.F.,Russian State Geological Prospecting University
Geotectonics | Year: 2010

The Red Sea Rift has been an object of comprehensive studies by several generations of geologists and geophysicists. Many publications and open-file reports provide insights into the geological history of this rift. Paleogene and Cretaceous rocks, which are considered to be prerift, are locally exposed at the margins of the Red Sea Rift. At the same time, some evidence indicates that at least some of these rocks are related to the early stage of the evolution of the Red Sea Rift. The available geological data suggest that the Red Sea region started its active evolution in the Cretaceous. As follows from lithostratigraphic data, the Cretaceous-Paleogene trough that predated the Oligocene-Quaternary rift covered this region completely or partially. The pre-Oligocene magmatism and geological evidence show that the Cretaceous-Paleogene trough was of the rift type. The Cretaceous-Eocene and Oligocene-Quaternary phases of rifting were separated by an epoch of uplifting and denudation documented by the erosion surface and unconformity. © 2010 Pleiades Publishing, Ltd.

Maria K.,Russian State Geological Prospecting University
Proceedings - SPE Annual Technical Conference and Exhibition | Year: 2011

The report focuses on the results of simulation of the near-well area heating by an electric current and the substantiation of using an electric field as a thermal method of oil production intensification. We give the description of such programs as NKAR (the program of the numerical solution of the direct problem of electrical logging), THERM3C (the program of solving the direct three-dimensional problem of thermometry) which were used in the simulation.

Karinskiy A.D.,Russian State Geological Prospecting University | Daev D.S.,Russian State Geological Prospecting University
Russian Geology and Geophysics | Year: 2016

The theory of resistivity logging (RL) originally stems from the Fock–Stefãnescu forward problem solution for the stationary electric field E in a piecewise homogeneous isotropic medium, with a single boundary corresponding to the surface of a cylinder unlimited by height. The cylinder simulates a borehole filled with drilling mud of resistivity ρ = ρb, which penetrates a formation with resistivity of rocks ρ = ρr. The primary field E is produced by the charge of a current electrode A placed on the cylinder axis. In this paper the forward problem for the field E is investigated for the electrode A at an arbitrary point off the axis of a borehole embedded in a transversely isotropic formation, with an anisotropy axis parallel to the borehole axis. The solution of forvard problem is used in algorithms and respective software for processing resistivity logs affected by electrode eccentricity and formation anisotropy. The changes caused to apparent resistivity by the two effects are estimated in percent for axial and lateral electrode dispositions. © 2016

Sadovnikov G.N.,Russian State Geological Prospecting University
Paleontological Journal | Year: 2016

The Middle Siberian volcanic plateau is characterized with respect to its paleoecological environments. In this area, volcanism commenced in the Severodvinian (Vishkilian) Age. The lower (tuffaceous) part of the plateau section (Lebedev deposits) was formed in the Vyatkian Age. Its middle (tufflava) part (Khungtukun deposits) is correlative with the Goudikeng Formation (interval of 65–111 m) in the Dalongkou type section of China and corresponds to the Quadrocladus pachyphyllus.. Echinolimnadia mattoxi Zone. The top of this sedimentary unit (111 m up from the base of the Goudikeng Formation) should be correlated with the base of the Otoceras Ecozone. The upper (lava) part of the plateau (Putorana deposits) corresponds to the interval of 111–210 m, belongs to the Elatocladus linearis.. Cornia vosini Ecozone, and is older than the Hindeodus parvus Zone, which is now considered as the basal unit of the Triassic marine sequences. The volcanic plateau section shows now evidence of any biotic crisis. © 2016, Pleiades Publishing, Ltd.

Farkov Yu.A.,Russian State Geological Prospecting University | Maksimov A.Yu.,Russian State Geological Prospecting University | Stroganov S.A.,Russian State Geological Prospecting University
International Journal of Wavelets, Multiresolution and Information Processing | Year: 2011

In this paper, we describe an algorithm for computing biorthogonal compactly supported dyadic wavelets related to the Walsh functions on the positive half-line ℝ+. It is noted that a similar technique can be applied in very general situations, e.g., in the case of Cantor and Vilenkin groups. Using the feedback-based approach, some numerical experiments comparing orthogonal and biorthogonal dyadic wavelets with the Haar, Daubechies, and biorthogonal 9/7 wavelets are prepared. © 2011 World Scientific Publishing Company.

Sadovnikov G.N.,Russian State Geological Prospecting University
Paleontological Journal | Year: 2015

Middle Siberian trappean volcanism is considered to have been one of the major causes of the fundamental biotic change at the Permian-Triassic boundary. Accumulation of tuffs dominated the initial stage of the volcanic plateau development (Exah time), while later (Khungturunian time), tuffs and lavas accumulated, and at the conclusive stage (Putoranian time) lavas prevailed. At the end of the eruptions the height of the plateau reached 1700 m. Over 200 species and 80 genera of plants, conchostracans, ostracodes, bivalves, fishes, gastropods are known from the Putoranian. This article contains the characterization of a Putoranian plateau biota for the interval between the conodont and ammonoid standards of the P-T boundary. © 2015, Pleiades Publishing, Ltd.

Sadovnikov G.N.,Russian State Geological Prospecting University
Paleontological Journal | Year: 2015

The formation of the Middle Siberian Traps has been considered one of the main causes for the change in the biota at the Permian-Triassic boundary. At the first stage of the formation of the volcanic plateau (Lebedevskian time), volcanism was dominated by tuffs; at the second stage (Khungtukunian time), by tuffs and lavas; and at the last stage (Putoranian time), by flood basalts. The paper presents a paleoecological characterization of the plateau at the middle (Khungtukunian) stage, immediately before the Permian-Triassic boundary (ammonoid standard). At the beginning of this stage the plateau reached an altitude of about 500 m above sea level, at the end of the stage it was higher than 800 m above sea level (Sadovnikov and Turlova, 2004). The Khungtukunian deposits have yielded more than 230 species, belonging to more than 70 genera of plants, conchostracans, ostracods, bivalves, and fishes. © 2015, Pleiades Publishing, Ltd.

Grechishnikova I.A.,Russian State Geological Prospecting University | Levitskii E.S.,Russian State Geological Prospecting University
Stratigraphy and Geological Correlation | Year: 2011

One of the most complete sections of the Upper Devonian-Lower Carboniferous in the Nakhichevan Autonomous Region in Azerbaijan is described bed-by-bed. The section is located on the northeastern slope of Geran-Kalasi Mountain. The section features a continuous succession of marine beds and abundant fossils, including foraminiferans, bryozoans, tabulates, rugoses, brachiopods, ostracodes, crinoids, conodonts, and algae. A few ammonoids found in the section have not yet been identified. In the process of composing the 1:25000 scale geological map, a complex brachiopod zone is for the first time accepted as a major stratigraphic unit (indicating the stratotype and an assemblage of zonal brachiopod species). © 2011 Pleiades Publishing, Ltd.

Sadovnikov G.N.,Russian State Geological Prospecting University
Paleontological Journal | Year: 2011

Quantitative analysis of taphocoenoses allows the recognition of dominants and codominants of the main associations and reconstruction of the taph, i.e., simplified skeletal structure of the lower units of the paleocatena, which is a reconstructed sequence of benthic communities on the slope of a sedimentary basin (Zakharov and Shurygin, 1985; Krassilov, 2003). Only aquatic and riparian associations are connected with the lithological characteristics of the taphocoenosis. The composition of zootaphocoenoses allows the hydrological mode of basins to be determined. The frequency ratio of basin and lowland associations is determined by the watering of the bottom of valleys and depressions. The frequency ratio of lowland and slope associations is determined by the ripeness of valleys. The frequency ratio of herbaceous and arborescent slope associations is determined by the ruggedness of terrain adjacent to the basin. © 2011 Pleiades Publishing, Ltd.

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