Eocene-Miocene oil shales in Azerbaijan: Stratigraphic controls on formation, distribution and hydrocarbon generation
Abbasov O.R.
Institute of Geology and Geophysics, Ministry of Science and Education Republic of Azerbaijan, 119, H.Javid ave., Az 1143, Baku, Azerbaijan, E-mail: ortal80@bk.ru
Based on the results of many years of field surveys, new information is presented on previously unknown oil shale outcrops in Azerbaijan. New boundaries of the distribution of oil shale-bearing facies were established. Role of stratigraphic controls in the distribution of oil shales within areas and outcrop sections, and their oil or gas generation capabilities were substantiated. The study of the source of oil shale parent rocks, and the features of oil shale basin that formed in the Eocene, Lower Maikop (first discovered in this study) and Miocene (Upper Maikop, Chokrakian and Diatom), made it possible to obtain some new regularities. Our results show that the kerogens of Eocene and Diatom oil shales demonstrate similar evolutionary histories that are noticeably different from the Maikop ones. Eocene oil shale kerogens, which show a closer connection with the marine environment demonstrate the ability to generate only oil, like Diatom kerogens, while the kerogen evolved in the Upper Maikop basin, which is subject to more terrigenous inputs and formed in a relatively freshwater environment, mainly shows the ability to generate gas.
Keywords: Azerbaijan, oil shale, formation, stratigraphic controls, regularity, oil generation capacity