ELECTRIC AND ELASTIC PROPERTIES OF DEEP-SEATED CONSOLIDATED ROCKS OF CARBONIFEROUS PERIOD OF THE CENTRAL GRABEN OF THE DNIEPER-DONETSK DEPRESSION

Abstract

Paper concerned the research of elastic and electric properties of deep-seated consolidated terrigenous rocks of Carboniferous period of the Central graben of the Dnieper-Donetsk depression (DDD). The purpose of the research was to study the petrophysical parameters of the consolidated reservoir rocks, as the basis of the integrated analysis of their physical properties. Such electric and elastic parameters of rock samples as resistivity and formation resistivity factor, formation resistivity enlargement factor, velocities of the P-waves and interval (transit) time have been studied. The correlation analysis has allowed establishing a series of empirical relationships between resistivity and formation resistivity factor, and between porosity and formation resistivity factor in atmospheric and reservoir conditions. The correlation relationships of the resistivity with formation resistivity factor manifest itself in linear function. Physical modeling of reservoir conditions allows adapting the values of electrical parameters obtained in atmospheric conditions to parameters of rocks in reservoir conditions. Laboratory acoustic study of siltstones and sandstones managed to establish correlation relationships of: velocities of the P-waves and interval (transit) time with density and porosity in atmospheric conditions; velocities of the P-waves in atmospheric and reservoir conditions; velocities with porosity in reservoir conditions. The dependence of the velocities of the P-waves in atmospheric and reservoir conditions for the studied rocks manifest itself in linear function. Physical modeling of reservoir conditions allows adapting the values of elastic parameters obtained in atmospheric conditions, to parameters of rocks in reservoir conditions. The correlation relationships of the electric and elastic properties with reservoir properties of siltstones and consolidated sandstones which were obtained in laboratory petrophysical research should be at the basis of preliminary interpretation of geophysical data on new areas of the Central graben of DDD.