Hydrocarbon potential and migration system of KashafroudFormation, in Kopet Dagh sedimentary basin, NE Iran

摘要

Kopet Dagh sedimentary basin is one of the promising areas for hydrocarbonexploration. Khangiran gas field producing gas and condensate from Surijeh (Lower Cretaceous) andMuzduran (Upper Jurassic) formation indicate that the area is atractive for further exploration activity.On that basis, 160 outcrop samples were selected from various geological sections and differentgeochemical techniques were applied for source rock evaluation. Rock-Eval analysis of samplesindicates that total organic carbon varies from 0.63 wt.percent in NW to 0.27 wt.percent in SE of thearea. Organic petrographic studies and elemental analysis of Kerogen indicate that the organic matterare mainly type III with minor amount of type II . Variation in sandston to shale ratio and vitrinitereflectance study show that Kitchen area lies on the NE of the area and organic matter are at thecatagenetic stage of maturation. The source potential index (SPI) was calculated using effectivethickness and average genetic potential. SPI variations indicate that hydrocarbon potentiality increasesfrom SE to NW of the area. Based on the various isothermal and isopach maps, charge factor andentrapment style system of migration of hydrocarbon was considered to be, undercharged laterallydrained low impedance.