EVOLUTION HISTORY FROM ANCIENT OIL RESERVOIR TO ANCIENT GAS RESERVOIR IN CARBONIFEROUS, EAST SICHUAN

Bashed on high pressure thermal simulation experiment,using kinetics method,the oil-generation period of Carboniferous in the east Sichuan and the oil-cracking gas quantity are calculated.The evolution history from ancient oil reservoir to ancient gas reservoir is studied.Combined with the Carboniferous inclusions homogenization temperature data of predecessors,according to the matching principle of hydrocarbon-generation period and injection period,the reliability of the calculation result is validated.Studies have indicated that,the ancient oil reservoir begins to crack into gas about 200 Ma ago(the Late Triassic)and continues till 135 Ma ago(the Early Cretaceous),which matches with the formation period(187—140 Ma)of the 3rd period inclusions of oil-cracking gas period.