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Том 71, № 3 (2016)
- Год: 2016
- Статей: 7
- URL: https://bakhtiniada.ru/0145-8752/issue/view/10649
Article
The Alan-Kyr Coniacian–Campanian section (Crimean Mountains): Biostratigraphy and paleobiogeography aspects
Аннотация
This investigation continues the study of the Alan-Kyr reference section (Central Crimea, Belogorsk Region). The zoned age difference in the stratigraphic scheme of the Upper Cretaceous in the Eastern European Platform is considered according to benthic and planktonic foraminifers, as well as radiolarians in the Alan-Kyr section. This fact can be explained based on the suggestion that stratigraphically important taxa could have appeared in Crimea several million years earlier than on the platform, where they could migrate under the great global eustatic transgression in the Early Campanian. We also considered the influence of paleobiogeographic conditions on the taxonomic composition of the zoned foraminifer complexes, both benthic and planktonic.
217-233
The special features of the interaction between iron-manganese stromatolites and the environment
Аннотация
The analysis of the submicroscopic textures of the cobaltiferous crusts from the Magellan Seamounts has shown that biofilms−ferromanganese stromatolite builders absorb petrogenic components (SiO2, Al2O3, P2O5, etc.) from the environment and use them for the formation of a columnar structure.
234-240
The identification and use of petrophysical anomalies to forecast the mineralization at the Antey uranium deposit (Southwestern Trans-Baikal Region)
Аннотация
The determination of petrophysical parameters in conjunction with the geological, structural, mineralogical, and petrographic study of rocks is necessary to assess the localization conditions of uranium–molybdenum ore, the processing prospects, and the extent of mineralization at the Antey vein–stockwork deposit, which is the Russia’s largest, confined to the granitoid basement of the Streltsovo Caldera in the Southeastern Trans-Baikal Region.
241-251
Perspectives of the discovery of large and unique noble metal deposits in the northeastern Siberian Platform
Аннотация
Geological prospecting indicators of a potential presence of the Witwatersrand-type large and superlarge noble metal deposits containing optional Pt, Ir, Os, Rh, U, and diamond are presented. Perspective areas of native gold concentration in the northeastern Siberian Platform are indicated. Gold metallogeny of this region was basically developed in Early Precambrian in association with greenstone belts and granulitegneiss complexes. Promising zones with noble metal mineralization encompass large areas at the junction of tectonic provinces.
252-261
The oil and gas potential of the Kuma rocks of the Bakhchisarai region of Crimea
Аннотация
The oil and gas potential of the Kuma Formation of the Bakhchisarai region (southwestern Crimea) was substantiated on the basis of a lithological and micropaleontological study of the rocks of the section of the formation and geochemical (luminescent-bituminous, gas-liquid chromatographic, pyrolytic, and isotope) studies of the organic matter of the rocks. New regions for study that are favorable for the origination of the oil system in this formation were identified.
262-268
The results of application of the VES-IP method during the study of sand–gravel mixes in Mosalsk district, Kaluga oblast
Аннотация
Vertical electrical sounding (VES) is a traditional method of exploration of sand–gravel mix (SGM) deposits. Geophysicists are challenged not only to determine the boundaries of SGM deposits, but also to determine their basic properties, for example, to locate the zones with high gravel contents within SGM deposits or determine the content of clay particles in sands. In order to meet these challenges, it is necessary to use new methods, in particular, the method of induced polarization (IP). This paper presents the results of direct-current VES-IP surveys that were carried out in the territory of Mosalsk district, Kaluga oblast, in 2015. The measurements were made at both known SGM deposits that are under development and new areas under prospecting where drilling has not been performed as yet. The study results show that all SGM deposits are characterized by high values of induced polarization. The complex adjustment of the apparent resistivity and apparent polarizability curves significantly confine the limits of equivalent models when interpreting the data in complex geological situations when sand-and-gravel deposits weakly differ from the host rocks or are superimposed with a thick layer of conducting clay loams.
269-274
The effect of soil salinity and the organic matter content on the thermal properties and unfrozen water content of frozen soils at the west coast of Baydarata Bay
Аннотация
This paper reports on laboratory results on the composition, structure, and properties of frozen and thawed soils on the western coast of the Baydaratata Bay. Experimental data that focus on the unfrozen water content and thermal properties of different soils are discussed and summarized. This effects of soil salinity and organic matter content on these properties were evaluated for frozen and thawed soils.
275-279