Abstract: In Bohai Bay basin Mesozoic and Cenozoic igneous rocks are widely developed,with mostly distributing along the strike-slip faults.The distribution regularity is in consistent with that of the oil and gas fields.Numerous studies show that magmatic activities have an important control role in hydrocarbon accumulation.However,the oil and gas exploration degree within Bohai sea is relatively low and there is not enough research on this area.Through integrated research on seismic and geological data,the magmatic activities mechanism jointly controlled by the " baton" type,namely west branch of Yanlu strike-slip faults of Huanghekou sag and stretch big fault has been analyzed.Therefore,the seismic logging response characteristics of igneous rocks,the space-time evolution regularities of magmatic activities have been made clear.And then the magmatic eruption pattern has also been established.On this basis,the heat brought by the magmatic activities and the promoting function of trace incompatible elements on hydrocarbon source rock evolution degree and conversion rate have been discussed.The studies results show the clay minerals formed under the alkaline environment has a transformation role on reservoir properties,and the igneous rock has a blocking role on oil and gas.All of these have provided a good reference for oil and gas exploration and development in the developed area.