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Moscow University Bulletin. Series 4. Geology

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No 1 (2019)
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https://doi.org/10.33623/0579-9406-2019-1

3-13 240
Abstract

Military activities lead to the transformation of all the ecological functions of the abiotic spheres of the Earth both in peace and wartime. The typification of the consequences of ecological situation changes caused by the development of the ecological functions of the abiotic spheres of the Earth under testing of weapons, rocket and space techniques and during conduction of hostilities are presented.

14-25 215
Abstract

Generalization of the results of years of research on the geochemistry of trace elements in the interstitial waters and sediments of the Black sea. The works were carried out in different areas, but in more detail described the material on the deep-water basin and facies profiles Yalta, Sochi landfills and profile directed from the Kerch Strait to SE. The behavior of biogenic elements (N, P, Si), B, J, Br and 18 metal elements according to ISP and ISP-MS is studied. Average concentrations of elements for 3 stratigraphic horizons are calculated. Factor analysis was used to process the results.

26-37 231
Abstract

For the first time during the last 100 years, the presence of Tirnovella occitanica ammonite Zone in the Berriasian section of Feodosia was confirmed. The results of sedimentological, bio- and magnetostratigraphic study of this interval are discussed in the paper.

38-45 214
Abstract

Volcano Girvas is a complexly constructed volcano complex of the Yatuli age. Apparently, it is a shield lava volcano, which was probably one of the supply channels of the vast lava field of the western Prionezhie region within the Girvas volcanic zone. Despite the fact that the Girvassky volcano is bare only fragmentary, the structure of the current is perfectly preserved in the rocks, allowing to reconstruct the direction of flow. Among these rocks, there is a zone of postvolcanic hydrothermal changes in the rocks, consisting mainly of nesting and veined tourmalization and silicification, as well as subsequent epidotization, sulfidization, chloritization and albitization. The zones of secondary changes are confined to faults, while their spatial-temporal correlation remains unclear. Reconstruction of the geological structure showed that there were two main processes at the Girvasa volcano: 1) pneumatolysis of type due to magmatic gases separated from gabbro-dolerite sills, 2) heating and circulation of exogenous waters with formation of near propylites. Based on the proposed scheme, thermodynamic modeling was performed.

46-56 251
Abstract

The article considers features of boundary Cretaceous–Eocene deposits in Belogorskiy district of Central Crimea. Structures interpreted as paleoseismic dislocations are described, their age, features of composition, history of formation are specified, magnitude and intensity of paleoearthquake are estimated. Steeply dipping fractures in Cretaceous rocks are regular and associated with dip and strike of the main regional structures. Their formation was caused by a transverse stretching during the main uplift of the structures at the beginning of the Eocene coinciding with the main phase of folding in Northern Turkey.

57-69 247
Abstract

The calcic nannoplankton of the Cretaceous deposits of the Bakhchsarai region of the South-Western Crimea was studied. In the Lower Cretaceous, it is extracted from the Rezan and Biasala Formations, in the Upper Cretaceous — from the Belogorsk, Prokhladnoye and Kudrino Formations. The age of the enclosing sediments by calcareous nannoplankton has been specified. In the Rezan Formation, the nannoplankton zone is not singled out; in the Biasala Formation, apparently, part of the NC5 zone is present. In the Belogorsk Formation, the UC3 zone, subzone b, is allocated (partially), in the Kudrino Formation — the UC20 zone, and the UC20b subzone. Upper and lower boundaries of the zones are not traced.

70-81 241
Abstract

Information on the structure features as well as new data on the distribution of calcareous nanoplankton (NP) from the Cretaceous-Paleogene boundary deposits of the Central Crimea is given. There is a rich complex of Cretaceous NP in both Maastrichtian and Danian rocks. Danian NP is sparse, poor preserved or absent. Lower Maastrichtian species Tranolithus orionatus (=Tranolithus phacelosus Stover) unknown in the Upper Maastricht of European sections and described only from the Upper Maastricht of the South-West of Tunisia is noted in Upper Maastrichtian rocks of studied area. Zones NP2–NP4 were determined in Danian rocks. The question of paleogeography is also concerned.

82-91 203
Abstract

A comprehensive geological and geophysical study of wave-like accumulative bodies on the continental slope of the Caspian Sea was carried out to determine their genesis. As a result, a regular change in the geometry of the layers and the composition of sediments on different morphological elements of waves were revealed, expressed in their textural and structural features, similar to the examples described in the literature for the regions of development of sedimentary waves.

92-97 305
Abstract

The Bazhenov Formation of Western Siberia is one of the most important and promising high-carbon formations. Its peculiarity is a huge area of distribution and high generation potential of its constituent deposits. Another feature of the formation is the predominance of silicides in its composition, among which the most interesting are radiolarites, which are often associated with hydrocarbon inflows. However, the mechanism of the forecast and the nature of their distribution still do not have an unambiguous solution. Based on a study of the composition and textural features of the structure of radiolarite layers in the clayey-siliceous rocks of the Bazhenov formation, a model of their formation based on the interaction of plankton (radiolarians) and currents is proposed.

98-106 176
Abstract

The use of several simultaneously operating sources in seismic operations allows one to obtain large amounts of data per unit of time than for classical works with a single source, and also to improve the seismic data recording system. Depending on the type of seismic source used (vibrating or pulsed), different methods of signal separation are used. When working with vibroseismic method, separation of signals becomes possible at the stage of correlative processing of vibrograms. In this paper, we demonstrate methods for constructing noncorrelating signals for use in vibroseis survey (with an example of using such signals on synthetic data) and hyperbolic median filtering to minimize correlation and incoherent noise.

107-114 282
Abstract

The article discusses the results of complex geological, geophysical and geochemical studies of gas-saturated sediments within the Kandalaksha gulf, the White Sea. As a part of the marine study detailed seismoacoustic studies were conducted, resulting in the geometry of the seabed, the distribution of geological peculiarities of the sedimentary sequence, including the zones of focused unloading of hydrocarbon fluids. It is shown that assemblages of the «gas caps» are confined to the zones of maximal thickness of post-glacial sediments. The composition of the organic matter in the sediments and the gas phase has been studied in detail.

SHORT MESSAGES

115-119 182
Abstract

A distribution of clay minerals in Quaternary sediments are revealed in the sedimentary system canyon — deep-water cone of the Shahe river in the Black sea. It is established that the ratio of illite, chlorite, smectite and kaolinite sustained by area and section is determined by the transfer of sedimentary material by turbidity flows through the canyon with the formation of a unified mineralogical province.



ISSN 0579-9406 (Print)