Геология

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 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.

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.

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).

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.

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.

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

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.

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.

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.