油气运聚模拟在目标钻前研究中的成功应用——以渤海海域渤中21-22区为例

Successful Application of Hydrocarbon Migration and Accumulation Modeling in Predrilling Target Study of Exploration Well in Bohai Sea Area

在对构造演化、成藏要素综合分析的基础上,运用盆地模拟技术对渤海海域渤中凹陷渤中21-22区的埋藏史、热史、生烃史以及油气运聚进行了模拟,指出了有利的油气聚集区。研究结果表明:渤中凹陷沙三段及东三段烃源岩在馆陶组沉积时期进入了大量生油期,现今均已进入大量生气阶段。渤中凹陷生成的天然气沿潜山表层风化壳以及大型不整合面运移至渤中21-22区潜山成藏。因而,渤中21-22区潜山是极为有利的油气勘探目标区。对该区的成功钻探验证了油气运聚模拟结果。因此,该油气运聚模拟技术是优选、评价有利勘探目标区、降低勘探风险并提升勘探成功率的有效方法。

Based on the comprehensive analyzing results of tectonic evolution and HC accumulation, the structure burial history, thermal evolution history, hydrocarbon generation, migration and accumulation history have been studied with basin modeling tech- nology for Bozhong 21-22 structure of Bozhong sag in Bohai Sea area. Favorable exploration areas and hydrocarbon accumulation area have been pointed out. The study results indicate that during the sedimentation of Guantao Fm, source rock of Sha-3 and Dong-3 Members in Bozhong sag entered into hydrocarbon generation period, and has reached gas generation peak nowadays. Gas generat- edfrom Bozhong sag migrated through anachoric crust of burial hill and large unconformity surface into Bozhong 21-22 structure and accumulated in burial hill. Thus burial hill of Bozhong 21-22 structure is very favorable target area for exploration. The simulation results of hydrocarbon migration and accumulation have been proved by successful exploration in this area. Therefore, the hydrocar- bon migration and accumulation simulation technology is an effective method for optimization and evaluation of favorable explora- tion area, and can decrease the exploration risk and increase the success rate of exploration.