Petroleum System and Petroleum Exploration in Qikou Sag. P
Yang Chiyin;Zhou Zongliang;Zhou Jiansheng Research Center of Petro-China Dagang Oilfield Company, Tanjin 300280
Qikou sap is a large and relative independentstructural-depositional unit developed since Tertiary.Uplifts surrounding the sag limit the space of geologi-cal elements distribution and hydrocarbon generation- migration-accumulation, so that only one petroleumsystem is formed in the sag. Based on geochemicalanalysis, the first and the third section of Shahejieformation are two sets of regional source layers, andtheir organic matters are dominated by Ⅱ_1 and ⅠKerogen type. Oil-source correlation shows that oiland gas were mostly from the third section of Shahejieformation, which is in high thermal evaluation level.The second order structure zones with different typeof traps made it favorable to form composite hydro-carbon accumulation zones that comprise multiple ty-pe of oil and gas pool and multiple oil and gas bearinglayers. Resource evolution for the plays in the beacharea shows that Baidong, Qidong and Chenghaistructures are rich in oil and gas. The resource in thesezones comprises about 60% of total oil resource and67% of total gas resource in the sag, which made thesezones to be the most favorable area for further hydro-carbon exploration.
【CateGory Index】： P618.13