油气藏形成过程中油气的再次运移

REMIGRATION OF OIL AND GAS DURING THE FORMING OF OIL AND GAS RESERVOIR

由烃源岩中排出的油气，经过初次运移、聚集和二次运移、聚集而形成的油气藏，当区域构造格局因受构造运动而发生改变或由于断裂的活动而使构造面貌发生变化时，已形成的油气聚集的相对平衡就被打破，油气沿区域不整合面或断裂向低势能方向发生再次运移，并在适宜的圈闭中再次聚集成藏。由于中国含油气盆地构造演化的多旋回性，因此油气的再次运移和再次聚集现象十分明显，深入研究这一问题具有十分重要的理论意义和实际意义。在研究这一问题时，要结合烃源岩热演化史、构造发展史和沉积史，确定烃源岩的分布、生储盖组合类型，恢复各期的构造格局和构造面貌，以确定油气再次运移的方向和再次聚集的位置。

When regional tectonic framework changed as a result of tectonic movement or tectonic topography varied due to faulting,the original reservoir was destroyedand oil(gas) remigrated along regional unconformity or fault towards the low-potential-energy direction,and accumulated to form the reservoir in suitable trap.Because of polycyclic evolution of petroliferous basins in China,it is very clear that oil and gas remigrated and reaccumulated.Attention to this phenomenon is of theoretical and practical importance,which should be combined with the analysis of thermal evolution history of source rock,and tectonic and sedimentary history to determine the distribution of source rock,source-reservoir-cap assemblage type,and reconstruct the tectonic framework and topography in each period,thereby determining the direction of remigration and of reaccumulation,guiding oil and gas exploration.