GEODYNAMIC MODEL, SEISMIC ACTIVITY OF THE SOUTH CASPIAN BASIN AND PERSPECTIVE DIRECTION OF OIL AND GAS FIELDS EXPLORATION

Abstract

Identifying seismically active zones on Earth, researches on accumulation mechanisms of geodynamic tension energy in the strong earthquake sources, the study of initial formation of mineral deposits especially the structures which have oil and gas fields and the formation of the genesis are explained with reference to the appropriate models. New models are preparing in contrast to plate tectonics recently, in the determination of geodynamic active zones and in the formation of the structures of oil and gas fields. One of such models is the model of theoretical grounds of Sh. Maruyaman in 1994, that is based on the idea of Tucho Wilson "plume mantle". According to this model the condition of formation of the South Caspian basin had been investigated. It was noted that, the creation of sedimentary layer’s morphostructure in this basin and accumulation of sediments with thickness up to 25 km had happend related to the process that was created by magmatism in the deep layers. Intensive subsiding has gone in the deepest part of the current basin in the South Caspian depression and the magma being frozen
ssharply reduced the movement in the outside areas near the Earth's surface and came out of the surface as volcano and subvolcano. Also magma had created intrusives in lots of places and consequently the current morphostructure of basin had been formed. Process of sedimentation had been started from previous periods of the Mesozoic in the region, the intensive decline of the Earth’s crust had been observed in the region approximately with the same tendency during the Jurassic period and rate of subsiding had been weakened at the end of the stage. Anomalous tension zones, regional tectonic faults, anticlinal structures located in sedimentary layer had been listed in certain arched, chain form related to these processes in the South Caspian depression. The South Absheron depression had organized center of whirlpool process during the (Bahar, Shahdeniz, Absheron, Shafag, Mashal, Babek, Umid, Bulla sea, Asiman, Zafar, etc.) Paleogene-Mezozoy period and large thickness sediments with hydrocarbon origin had been accumulated in this area. In our opinion, the possibility of rich hydrocarbon deposits are quite convincing in Bahar, Shahdeniz that currently observed along with the Absheron, Shafag, Mashal, Babek, Umid, Bulla sea, Asiman, Zafar and etc. anticlinal structures. Areas with these structures are recommended for three-dimensional (3D) seismic exploration works along with the possibility to study depths down to 60 km with the method of seismic tomography to evaluate the hydrocarbon potential in deep layers within interval of 6-15 km.