构造活动对莱州湾凹陷油气成藏的影响

通过对莱州湾凹陷构造活动、生储盖组合及所发现原油地球化学特征的分析,认为影响该区油气成藏的构造活动主要为喜山运动和郯庐断裂活动。古近纪晚期喜山运动引起的区域性地壳抬升,使得莱州湾凹陷及其周围凸起东营组顶部泥质盖层遭受剥蚀,早期形成的古近系下组合油藏中的烃类因埋深变浅或有效封盖层变薄而遭受了严重的生物降解;郯庐断裂活动对区内构造形成、沉积发育、上组合油气成藏起到了重要作用,走滑断层不利于油气运移,地层与断层的产状配置关系控制了新近系上组合油气富集部位。

Tectonic impacts on hydrocarbon accumulation in Laizhouwan sag

By analyzing tectonic activities,hydrocarbon source-reservoir-seal associations and crude geochemistry in Laizhouwan sag,it is considered that the main tectonic events to control hydrocarbon accumulation are Himalayan movement and Tanlu Fault activity.As a result of Late Paleogene uplifting by Himalayan movement,a shale seal on the top of Dongying Formation in Laizhouwan sag was eroded,and early-formed lower oil accumulations in Paleogene suffered severe biodegradation due to their shallowing and the effective seal thinning.Tanlu Fault activities played an important role in structure development, sedimentation and upper hydrocarbon accumulations in Neogene in this area,but the strike-slip faults were harmful to hydrocarbon migration.The occurrence relationship between stratum and faults has controlled locations of upper hydrocarbon accumulation in Neogene.