The South Caspian Basin was formed as a result of the interaction of the Eurasia, India, Arabia, and numerous microplates starting from the Trias-sic. During the Late Triassic–Early Jurassic, several microplates were sutured to the Eurasian margin, closing the Paleotethys Ocean. A Jurassic–Cretaceous north-dipping subduction was developed along this new continental margin south of the Pontides, Trans-Caucasus, and Iranian plates. This subduction zone trench-pulling effect caused rifting, creating the back-arc basin of the Greater Caucasus–proto-South Caspian Sea, which achieved a maximum width during the Late Cretaceous–early Paleogene.
During the Eocene, the Lesser Caucasus, Sanandaj-Sirjan, and Makran plates were sutured to Trans-Caucasus–Talesh–South Caspian–Lut system. The subduc-tion zone jumped to the Scythian-Turan margin. The South Caspian underwent reorganization during the Oligocene–Neogene. Northward movement of the South Caspian microcontinent (SCM) resulted in rifting between SCM and Alborz plate. The southwestern part of the South Caspian Basin was reopened, whereas the northwestern part was gradually reduced in size. The source rocks of the Maikop Formation were deposited in the South Caspian Basin during the Oligocene–early Miocene.
The collision of India and the Lut plate with Eurasia caused the deformation of Central Asia and created a system of northwest–southeast wrench faults. The remnants of the Jurassic–Cretaceous back-arc system oceanic and attenuated crust, as well as Tertiary oceanic and attenuated crust, were locked between adjacent continental plates and orogenic systems. Thick molasse-type sediments that accumulated during the Pliocene–Quaternary provided reservoir rocks and contributed to the burial and maturation of source rocks.
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Oil and Gas of the Greater Caspian Area
Throughout time, the greater Caspian area has maintained its position as one of the major petroleum provinces in the world. Its early history as a prolific producer of oil is well known. Caspian region exploration dates to the seventh century B.C., during the time of the Median Kingdom in today's southern Azerbaijan. Oil played an important role in the everyday lives of these ancient tribes of the region, and it is still a very important commodity today. The past two decades have seen many important advances in our knowledge of the geological evolution of hydrocarbon-bearing sedimentary basins. The success of modern exploration is, to a large extent, based on new advances in both deep and 3-D seismic imaging, as well as improved pressure-prediction and pre-drill oil and gas quality predictive methodologies, to mention just a few. Nevertheless, large areas of the greater Caspian region have remained unexplored due to a variety of factors such as deep-water conditions and zones with high pore-pressures in the South Caspian Sea and The Black Sea, and vast shallow-water regions with harsh winter ice conditions in the North Caspian Sea. This publication contains 12 extended abstracts and 6 full-length papers that discuss technology development, challenges in estimating proven and potential reserves, outcrop-based studies of potential reservoirs, regional tectonics and geodynamic evolution, and source rock and stratigraphic analyses of the greater Caspian area.