Analysis of Pool Forming Periods in Jurassic Yanqi Basin

This paper focuses on the study of the pool forming periods of the hydrocarbon by means of organic geochemistry. The correlation of petroleum sources shows that Jurassic Badaowan Formation is taken as main hydrocarbon source bed, Triassic is as the second source. Firstly, the hydrocarbon migrated laterally at short distance, then into Sangonghe and Xishanyao formations along the path of faults. This basin had undergone two periods of producing hydrocarbon, the main period of producing hydrocarbon is the end of Jurassic, secondly is the late of Tertiary. The distribution, homogenization temperature and components of fluid inclusions, dating of anthigenic illite, and maturity of hydrocarbon in the reservoir reveal two periods of pool forming in the Late-Middle Jurassic of the Yanqi basin, the first event for the generation, migration and accumulation of low maturity hydrocarbon happened during the late Jurassic Badaowan Formation, and the second event for maturity hydrocarbon happened during the end of Jurassic. The fluid inclusions and the isotope chronology of anthigenic illite in the reservoir haven't recorded the producing hydrocarbon and pool forming during the late of Tertiary. Main pool formations took place in the late of Jurassic, and has been adjusted with finality during the late of Tertiary.