Effect of salt-bearing sequences on distribution of possible generation zones and on the phase state of hydrocarbons (based on the Caspian Depression)

Abstract

We propose a new methodology of determining paleo-temperatures, based on calculations of densities of paleo-heat flows. We present maps of the regional overall background of the paleo-temperatures of the sub-salt sequences (Upper Carboniferous - Lower Permian) up to the beginning of the largest stages of the history of the geological evolution of the depression, and recognize sectors of stage-by-stage entry of these deposits into the main zone of oil formation. The paleo-tectonic and paleo-temperature reconstructions enable us to regard the Riphean-Vendian deposits as a possible source of hydrocarbon generation during the early (late Proterozoic - early Paleozoic) stages of evolution of the Caspian Depression.