Regularities of Distribution of Oil and Gas Deposits by Size of Reserves in Sedimentary Thickness

The work is devoted to the estimation of prospects of oil and gas potential and to increasing of efficiency of geological prospecting works in the oldest oil and gas region of the pre-Caucasus. Actual material of approximately 300 deposits was used. The productivity level of deposits includes several stratigraphic complexes. The areas of distribution of oil and gas fields in stratigraphic complexes were mapped. The predominant direction of distribution of oil and gas potential on stratigraphic complexes in each of these areas is given. The distribution of hydrocarbon deposits by depth, stratigraphic complexes and reserves is shown. The regularity of hydrocarbon deposits in more ancient complexes to a greater depth is traced. Along the trend there is a decrease in the level of oil and gas positional. Along the line of trend there is a tendency of decreasing of deposits size in case of predominance of liquid hydrocarbons. The value of reserves along the trend tends to increase in the case of gas predominance. The deposits which by of the size reserves fall on numerical values from the described tendencies are marked. This can be explained by the existence of non-pre-searched or not discovered deposits in the prospective stratigraphic complexes.