Abnormal pressure regime in the former USSR petroleum basins

This paper represents a continuing attempt to summarize the large volume of geological and geophysical research on abnormally-high and abnormally-low pressures in different regions of the former USSR. There are many regions with abnormally-high and abnormally-low pressures. Examples can be found in the western, eastern and northern Siberia, Crimea, Caucasus, Caspian basins, Ukraine, Volga-Ural and the Timan-Pechora regions of Russia, and Sakhalin Island (Fig. 1). In these regions, the abnormal pressure is associated with significant hydrocarbon accumulations. For better understanding of abnormal formation pressures, it is necessary to conduct research on hydrodynamics and the origin of abnormal pressure. Based on observation of abnormal pressures in the former USSR petroleum basins, the authors present their theory on the origin of abnormal pressure.