The article presents a new method for geological and geophysical modeling developed by the authors and results of its application in Volga-Ural oil and gas region. In contrast to the commonly used practice of qualitative interpretation of transformed anomalies maps containing significant errors, the new method allows quantitative interpretation of gravity field without its separation into components. The method is to solve the inverse linear gravimetry problem, in which simultaneously with the selection of the theoretical and measured fields the density models of objects are forecasting. The results are density models of the oil-bearing structures has the high geological reliability confirmed by aprioristic information on rock density, determined from the core samples and well. The example of South Tatar crest shows high physical and geological confidence of gravity modeling for the geological studies of the oil-bearing structures.
Over basement faults in the sedimentary strata there are relative decreasing of the density. These faults connected with a natural rocks decompression traceable across the sedimentary complex over the oil deposits. It shows the local gravity anomalies, identified by high-precision gravity surveys. The interpretation of these anomalies by gravity modeling allows predict oil and gas structures and the possible accumulation of hydrocarbons in the basement.
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