辽西南洼油气运聚模拟及有利区带预测

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

分析近年渤海油田的勘探失利探井,因油气运移充注风险失利高达61.5%。鉴于海上油气勘探成本高、钻井密度小,在海上矿区内开展油气运聚模拟分析可以大大提高勘探成功率。辽西南洼是渤海湾盆地内勘探程度较低的区域,通过模拟辽西南洼烃源岩埋藏史、热史和成熟生烃史,构建三维地质模型,分析辽西南洼原油整体上的运移和分布特征,预测可能的有利油带聚集区。模拟结果表明北次洼西部缓坡断裂带是重要的油气运聚区域,为该区下一步油气勘探提供了依据,同时对勘探程度较低的盆地或凹陷有效提高勘探成功率具有重要指导意义。

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.