The article provides the petrological and petrophysical characteristics of metamorphic rocks. Information on petrotypes of metamorphic rocks, reservoirs properties and saturation is given. Oil saturation is detected in moved weathering crust, double-mica’s shales, quarts-muscovite-biotite’s, feldspar-quarts-biotite’s, feldspar-amphibolite’s shales and serpentinite. Hydrocarbons impregnate the cementing mass in terrigenous rocks, in crystalline rocks hydrocarbons may be found in the cracks; hydrocarbons impregnate the hydromica mass that develops on the feldspars, form films on the walls of the leaching pores, or completely fill pores. Oil saturation is observed along the boundaries of newly formed carbonates in carbonized serpentinite, saturation has spotted character in the slightly altered serpentine. Hydrocarbons are present in the dolomite-talc aggregate performing cracks, impregnating the Talc and giving it a black color. Hydrocarbons are marked in filiform cracks, preserved as relics of the serpentinite loop structure. Well logging is used to show the possibility of petrological division of the weathering crust and the Paleozoic. Serpentinites and its carbonated ones, rocks of residual and mixed weathering crust surely stand out by standard logging. But Identify of mica’s shales and gneiss is difficult with standard logging.
It has been shown that the structure of the void space of metamorphic rocks is predominantly porosity-fractional and fractional. The porosities type of reservoir takes an insignificant part of the section. Comparison of calculated parameters of the density and acoustic logging of the solid phase is recommended to identify type of the void space. To improve the reliability of the petrophysical interpretation of the metamorphic rocks is recommended to use special methods of well logging.
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