The simulation of hydrocarbon migration and accumulation and the prediction of favorable zone in south subsag of Liaoxi Sag

The analysis on failed exploration wells in Bohai Oilfield in recent years shows that the failure caused by hydrocarbon migration and charging risk is up to 61.5%.In view of the high cost and low well density of offshore oil and gas exploration, the simulation analysis on hydrocarbon migration and accumulation in offshore mining areas can greatly improve the exploration success rate.The south subsag of Liaoxi Sag is an area with low degree of exploration in the Bohai Bay Basin.The burial history, thermal history and mature hydrocarbon generation history of source rocks in south subsag of Liaoxi Sag were simulated and a three-dimensional geological model was constructed to analyze the overall migration and distribution characteristics of crude oil in this area and predict possible favorable oil accumulation areas.The simulation results show that the fault belt of the western gentle slope in the northern part of south subsag is an important hydrocarbon migration and accumulation area.The research results provide a basis for the future oil and gas exploration in this area and play a guiding role in improving the exploration success rate of basins or sags with low exploration degree effectively.