The surveyed area contains of four major oil and gas-bearing sequences of Eifelian-Bashkirian age which attribute to 90% of resources. While conducting 3D seismic survey operations in the scope of over 700 sq. km and when hundreds of deep wells are available, the following criteria have been identified as defining oil and gas-bearing capacity of each sequence: fault-block structure of Devonian deposits, Bobrikovian bioherro lodging structures effect of wash-out and karst-forming processes on Visean-Bashkirian pay deposits