Laizhouwan depression in the southern Bohai Bay is complicated in hydrocarbon accumulation and is low in exploration maturity.An oil discovery with reserves around hundred millions of tons was obtained recently.Laizhouwan depression is characterized by fault depression and strike-slip inversion.According to the feature and strength of fault activity

the faults were divided into three types which have different control on depression pattern

sedimentary system and hydrocarbon migration system.Furthermore

the tectonic evolution of Laizhouwan depression was divided into three stages:the early rifting stage during deposition of the Kongdian Formation to the Member Ⅲ of Shahejie Formation

the strike-slip stage during deposition of the Member Ⅱ of Shahejie Formation to Dongying Formation and the late activation stage since the Neogene.The tectonic evolution controls trap formation

sediment filling

subsidence center migration

and source rock formation and evolution.The late strong tectonic and volcanic activities are helpful for late hydrocarbon accumulation in Laizhouwan depression.