东濮凹陷西南洼断层的油气输导作用与机理探讨

Mechanism of hydrocarbon migration and accumulation in southwest sag of Dongpu Depression

国殿斌 2 向才富 4 蒋飞虎² 李继东² 袁波² 梅冰²

中国石化石油勘探开发研究院，北京 100083 中国石化中原油田分公司勘探开发研究院，河南 郑州 450000 中国石油大学油气资源与探测国家重点实验室，北京 102249 中国石油大学（北京）地球科学学院，北京 102249

Petroleum Exploration and Production Research Institute, SINOPEC, Beijing 100083, China Research Institute of Exploration and Development, Zhongyuan Oilfield Company, SINOPEC, Zhengzhou 450000, China State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China College of Geosciences, China University of Petroleum, Beijing 102249, China

西南洼是东濮凹陷重要的勘探领域接替区，以其新发现的方里集含油气构造为研究对象，通过油气性质的空间分布探讨了断层对油气运聚的作用。研究表明：不同时期活动的不同类型、不同级别的断层对油气的运聚作用不同，东营末期停止活动的二级断层和三级断层最有利于油气运聚，每个断块都有独立的运聚体系；调节断层（如高平集断层）发育的部位油气相对富集，表现在原油物性变好和天然气干燥系数增加；断块掀斜作用控制了油气的富集和贫化，东营末期的构造掀斜造成局部圈闭油气的调整破坏，新近纪末期充注的油气是研究区重要的勘探对象。油气资源的晚期聚集决定了西南洼具有重要的勘探前景。

The Southwest Sag developed in the Dongpu Depression of the Bohai Bay Basin is the most important new target for hydrocarbon exploration. The function of the fault in hydrocarbon migration and accumulation was discussed based on the characteristics and the space distribution of petroleum from the newly founded Fangliji hydrocarbon-bearing structure. The results show that different types and different branches of the faults formed at different periods have different functions in hydrocarbon migration and accumulation, and the second and the third grade faults that ceased to be active at the end of the Dongying Period are more favorable for hydrocarbon migration, and different blocks tend to form distinct hydrocarbon migration and accumulation unit; the location where the northwest adjustment faults were developed(for example, the Gaopingji Fault) is a place that the hydrocarbon enrichment is indicated by lower physical property of the petroleum and higher C1/C1￣4 ratio in the natural gas; the tilting of the faulted block controlled the enrichment and the depletion of the hydrocarbon, and the adjustment of the faulted block at the end of the Dongying Period has resulted in the hydrocarbon depletion in the local traps developed in the Fangliji District. The hydrocarbon accumulated in the Neogene Period is the main target for hydrocarbon exploration. The late-stage hydrocarbon migration and accumulation justfy our judegement that the Southwest Sag is the most important new target for hydrocarbon exploration.

10.6056/dkyqt201702005