Mud volcanoes in the South Caspian basin: Nature and estimated depth of its products

In paper based on the results of previous studies and latest investigations of mud volcanoes in the South Caspian basin the depth occurrence of fluid, mud and rocks are calculated and modeled. Major factors causing formation of diapirism/mud volcanism in the South Caspian basin are Pliocene-Quaternary high sedimentation rates (up to 3 km/my), super thick sedimentary cover (up to 25 30 km), predominance of clayey rocks (reaching 80%) in the section, low temperatures (with 15 ̊C 18 ̊C/km gradient), overpressures reaching lithostatic, the onset of petroleum generation lowered to considerable depths. The majority of the mud volcanoes are associated with the petroleum bearing structures. Depths where the liquid, gaseous and solid products of mud volcanoes are sourced appear to be different. The gases have the deepest roots (7 15 km) which are the main force in formation and activity of MVs. Source of the fluidized clayey mass does not lie below 3 4 km. Oils emitted by mud volcanoes are the product of destruction of petroleum accumulations occurring beneath them.