莱州湾凹陷断裂控藏机理

莱州湾凹陷是受郯庐断裂多期活动控制形成的富油气凹陷。断裂演化对凹陷油气的生成、运移和聚集均产生了重要的影响。凹陷断陷期的快速沉降导致了古近系沙河街组沙四上段和沙三中段优质烃源岩的发育；断裂沟通深部热源上涌，较高的地温梯度加快了烃源岩的成熟演化；断裂成为油气纵向运移的优势通道，控制了油气的纵向排放；后期强烈的断裂活动对早期油气藏具一定的破坏作用。

Mechanism of Controlling of Fault on Oil Accumulation in Laizhouwan Sag in Southern Bohai Bay Basin

Laizhouwan sag is the hydrocarbon?rich sag controlled by the multi?episode movements of Tanlu fault. The fault evolution has important effects on the hydrocarbon generation, migration and accumulation in the sag. The rapid subsidence in the faulted period caused development of high?quality source rocks of E2s41 and E2s23. At the same time, the fault communicating with deep thermal source allows it to flow up, leading to high geothermal gradient which accelerated the maturity evolution of the source rocks. So the fault becmes advantageous channels for vertical hydrocarbon migration, and controls the vertical expulsion of hydrocarbons. The late intense fault activities have certain destructive effects on the early preexisting oil and gas reservoirs