桩西潜山成藏条件及油气富集规律

Reservoir condition and accumulation regulation of Zhuangxi buried hill

针对潜山表层风化壳油藏研究较多,潜山内幕油气成藏规律研究较少状况.从油源条件、构造活动对储层发育、输导方式和封堵盖层的配置等角度研究了桩西潜山成藏条件和富集规律,孤北洼陷和桩东凹陷为其提供了丰富的油源,储层、盖层、圈闭的发育主要受控于褶皱和断裂构造,由此形成以裂缝为主的复杂圈闭组合.油气沿油源断层和褶皱-断裂-裂缝进入潜山内幕溶蚀带成藏.油气分布主要受控于裂缝发育程度,正断层尤其是油源断层对下古生界储层改造是油气运移指向区,逆断层下盘地层挠曲形成缝洞发育带可形成富集高产油藏.

Studies have been made more on the weathering crust reservoirs at the top of buried hills,but less on the law of insider hill reservoirs.In this paper,reservoir conditions and accumulation regulation of Zhuangxi buried hill were discussed from the view point of oil source,tectonic activity on the reservoir,transporting mode,and sealing cap layer.Zhuangxi buried hill has rich oil source provided by Gubei Subsag and Zhuangdong Sag.Reservoir,seal and trap were mainly controlled by folds and faults,thereby complex trap combination was formed,mainly dominated by crack.Oil and gas migrated into the inside storey of buried hill dissolution reservoirs by the way of oil source faults and fold-fracture-cracks.Oil and gas distribution was mainly controlled by the development degree of fracture.Lower Paleozoic reservoirs reconstructed by normal faults especially oil source faults were the favorable directional zones of hydrocarbon migration,and high-yielding reservoirs mainly distributed in seam cave zones formed by reverse-faults footwall strata deflection.