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Integrated Bio and Magnetostratigraphic Study of the ≪Ozerki≫ Sections (Upper Cretaceous, Right Bank of the Volga in the Saratov Region). Paper 2. Oryctocoenosis Characteristics and Biostratigraphy

In the ≪Ozerki≫ sections, in the terrigenous and carbonate rocks, a faunal complex has been determined – unusually diversified and relatively abundant for the right-bank part of the Saratov Region. Examination of the specified groups of fossil invertebrates has allowed to propose variants for biostratigraphic division and correlation of the sections under consideration. The carbonate rocks are supposed to belong to the Turonian-Coniacian and the underlying terrigenouscarbonate rocks are regarded as the Lower Turonian ones.

What is the «Anthropocene»?

The unofficial term ≪Anthropocene≫ is used actively to refer of the era of the global role of mankind in changing of the environment. Its beginning was announced at the International Geological Congress in 2016. Earlier geologists abstained from this discussion, and representatives of other Earth and Life sciences prevailed among supporters of anthropocene’s idea. In the near future, the introduction of the anthropocene in the geochronological scale will be of current interest.

The Petrophysical Survey of Radioactive Logging for Interpritation (in South-West Part of Pribortovaya Zone Prikaspiy)

In this article was studied clayiness of key bed of Aleksinskie depositsof Severo-Limanskaya region. It was executed 14 analyses of big collection of mineral aggregateusing X-ray analysis. It was received quantity relations clayiness and silty parts in key clayiness beds. It was calculated qualified significances of hydrogen index for examined key bed, using known valuesof hydrogen content of basic clayiness minerals.

New Data on Magnetic Properties of Upper Paleozoic Deposits in the South of Precaspian Depression

The magnetic properties of igneous and sedimentary rocks of Lower Carboniferous and Upper Permian, were studied in the core samples from the boreholes, situated in the south of Precaspian depression. The volcanic rocks of Lower Carboniferous are characterized by low (first decades 10-5 SI units), and Upper Permian – by high (hundreds and first thousands 10-5 SI units) values of volume magnetic susceptibility.

The Anomalous Lithosphere and the Oil and Gas Potential of the Precaspian Depression

The lithosphere of the Precaspian depression is characterized by abnormal ratios of the super-thick sedimentary cover and the thinlayered suboceanic crust, as well as anomalous structure of the decompacted upper mantle. The classic models of isostatic equilibrium for the Precaspian depression are insufficient and applicable only to a first approximation.

Secondary Terrigenous Screens of the Tyumen Switch – Reliable Factor of Preservation of Productivity Bazheno-аbalak Complex

Reliable isolation of the Bazhenov-Abalak complex of the Krasnoleninskoye field, ensuring its productivity, was provided by the appearance of secondary (hydrothermal) screens in underlying rocks of the Tyumen Suite. This was reflected in the sealing of the intergranular space of sandstones, silty sandstones and other rocks of the Tyumen suite with regenerative quartz, minerals of silica, and rarely sulphates and carbonates.

On the Stratigraphic Significance of Elasmobranchs (Chondrichtyes, Elasmobranchii)) in the Cenomanian of the Volga River Basin (Right Bank)

The paper analyzes the stratigraphic distribution of elasmobranchs in the deposits of the Melovatka Formation (Cenomanian) from the right bank of the Volga (part of the Penza, Saratov and Volgograd regions).

First Magnetostratigraphic Data on the Maastrihtian of Mountain Crimea (Bakhchysarai Region)

The representative data about magnetic susceptibility, its anisotropy before and after heating up to 500°C and other petromagnetic characteristics were received on two sections of carbonate sediments of Maastrihtian – Chahmahly and Takma, located in Bakhchysarai region of the Republic of Crimea. In the studied sections there were established the magnetozones of normal and anomalous polarity, the comparison of determined zones with Geomagnetic Polarity Time Scale was conducted.

Auutygenic Dolomite High-сarbon Radials Bajenovskaya Switches – Indicator of the Regime Active Singenic Naptidogenesis

The article is devoted to the role of algal material of the Bazhenov suite in the the formation of authigenic dolomite. Authigenic dolomite could form in the environment of convergence of two processes: hydrothermal («wedging out» in the rear zones) and catagenetic (background) generated by conductive heat transfer. The development of the algal dolomite in situ shows that the source rocks experienced the stage of intensive (final) hydrocarbons generation.

Lithogeochemical Properties оf Terrigenous Rocks of Sortymsky Suite of Pyakyakhinskoye Field (North of Western Siberia)

The article represents lithogeochemical characteristics of rocks of sortymsky suite. It is revealed that the rocks belong to sellitem and the hydrolysates, the values of Sodium Module and Potassium Module indicates on sediments of greywacke containing hydromica, chlorite, plagioclase. Degree the maturity received by a thin pool alumosilicates was moderate (CIA < 70). Sortymsky the basin was characterized by shallow depth with an increase in salinity of the East to the West.

The Content of Mobile Forms of Heavy Metals in a Soil Cover of the City Park of Volsk Town

The soil cover in the territory of the recreational zone «City Park» located in the central part of the Volsk town of the Saratov region is investigated. The assessment of a current sanitary and hygienic and ecological and geochemical state of soils is executed by results of the analysis of concentration of mobile forms of heavy metals. Excess of threshold limit values on nickel, copper and zinc is established.

Prospects of Geological Modeling of Oil and Gas Bearing Reservoirs While Drilling

In this paper, we consider the technology of geological modeling of oil and gas reservoirs, based on the results of interpretation of the mud logging and well logging data. Informative geological and geophysical parameters for distinguishing marking horizons were determined. A technological scheme for opening productive reservoirs is proposed, based on the allocation of reference layers of different levels.

Correlation Transformation of Field Vibragram with the Account of Distorces of Phase Spectrum of Swip-signals

The original method of correlative transformation of vibrograms, which takes into account the distortion of reference signals in environment with frequency-dependent attenuation on the energy of elastic vibrations. The experimental material shows that the proposed method of calculating correlograms allows to significantly improve the quality of vibroseis materials. The possibility of calculating the attenuation decrement, which carries a significant amount of additional information on the structure and properties of the geological section, is also discussed.

On the Genus Balantionella Schrammen, 1902 (Porifera, Hexactinellida)

The Balantionella genus has been recognized by A. Schrammen (1902) from a single specimen and two skeleton fragments from a locality in the «quadrate» Cretaceous rocks in Germany. In the southeast of the Russian Plate, representatives of the genus have been determined within units from all the stages of the Upper Cretaceous. This has made it possible to provide characteristics and to trace the morphogenetic tendencies in the representatives of the group. Three subgenera and 12 species have been recognized.

Geological Structure and Petroleum Potential of the Svintsovskaya Depression Devonian Deposits in the Saratov Region

Based on geological survey data from previous years, it is safe to say that there is a possibility of oil and gas discovery in the Devonian terrigenous-carbonate deposits, similar to the findings in the regions known as the Ryazano-Saratovsky Basin and the Stepnovskaya Anticline, as well as its adjacent areas. Yet the geological structure and a potential for discovery of recoverable hydrocarbon deposits within the Svintsovskaya Depression are still unclear.

New View at Field Methods of Precision Graviprospecting Works in the Complex of Geophysical Methods of Investigation

The paper represents materials which evidently show small amplitude faults in the gravitational field, poorly seen in a wave field, and appearance of peak of instability among ∆g curves reflecting features of «thin structure» of the gravitational field which can be considered as objects potentially containing oil and gas. The purpose of this paper is an attraction of attention of users of subsoil resources on necessity to carry out precision gravimetric or even better to do gravimagnetic investigations along seismic profiles using combined scheme. 

The Vertical Range of Foraminifera in the Senomanian Deposits of the Right-Bank Volga Region (South of the Penza, Saratov and North of the Volgograd Regions)

The paper represents an analysis of the vertical range of foraminifera in the Albian-Senomanian-Turonian interval from sections of rightbank of the Volga region (the south of the Penza, Saratov and the north of the Volgograd regions). It is suggested to establish two local biozones: Gavelenella cenomanica and Lingulogavelenella globosa within the Melovatkian suite (Senomanian stage).

Melovatka suite (senomanian stage of the right bank of the Volga region): new data on stratigraphic position and volume

This paper represents results of the complex research of the Senomanian deposits from right-bank of the Volga region. It is suggested to revise the stratigraphic position and the range of previously established Melovatka suite (1999) (Senomanian stage). It has been revealed that major part of the middle (silt-argillaceous packet) subsuite and the upper (sandy packet) sub-suite are missing from the stratotype section, but determined by the author within the Senomanian stage of the right-bank Volga region.

Origin of Geoecological Research in Saratov University

Manifestation of natural disasters during growth of cities in the Volga Region revealed amount of geoecological problems in the beginning of the 20th century. Increasing of these problems forced engineeringgeological research with elements of geoecological investigations in the Geological scientific Institute of Saratov University. This work provided a basis for geoecological, urboecological and agroecological research in the University. 

Hydrothermal Nature of Cavern Formation in the VendianRiphean Collectors in the Baikitskaya Anteclise – a Key to Predicting Zones of Oil and Gas Accumulation

The joint Vendian-Riphean reservoir in the Yurubcheno-Tokhomskaya zone (YuTZ) of the Siberian Platform has resulted from hydrothermal activity. Prediction of the HC-prospective fields in the VendianRuphean deposits is based on revealing the zones of hydrothermal activity conductive to cavern and pore formation in the fractured carbonate series. Quartz-associated ankerites are indicator minerals for oil- and gas-saturated dolomites.