应用钻井测试资料、地震资料和盆地模拟技术对伊通盆地莫里青断陷地层压力演化史和油气运移史进行了研究。莫里青断陷地层压力经历了3次"幕式"聚集与释放,压力演化与构造运动关系密切;莫里青断陷现今地层压力以常压为主,局部残留弱超压;岩相、沉积速率、生烃作用及断裂活动对地层压力差异分布有重要的影响;莫里青断陷超压释放期油气运移活跃,超压释放为油气运移提供了驱动力;渐新世中晚期是莫里青断陷油气运移的主要时期;尖山构造带和靠山凹陷处于双阳组油气运移的有利指向区;靠山凹陷西北部油气成藏条件优越,油气富集程度较高,是研究区油气勘探的有利区带。
Based on the drilling test data and seismic data,the basin modeling technique is applied to reconstruct the pressure evolution history and hydrocarbon migration in the Moliqing fault-depression in the Yitong Basin.Three episodic accumulations and releases of pressure occurred in the Moliqing fault-depression,and the excess pressure evolution has a close relation to tectonic movements.The formation pressure distribution is characterized by normal pressure in almost the entire fault-depression with weak residual overpressure locally.The difference of pressure distribution is mainly caused by the rock facies,sedimentation rate,hydrocarbon generation and fault activities.The hydrocarbon migration is more active during the release of the pressure,which mainly happened during the middle-late Oligocene and provided the driving force for hydrocarbon migration.The hydrocarbon migration was directed to the Shuangyang Formation within the Jianshan uplift and the Kaoshan Sag.With the good conditions of hydrocarbon accumulation and higher hydrocarbon concentration,the northwest part of the Kaoshan Sag is considered as a favorable area for the oil and gas exploration in the Moliqing fault-depression.