葡西油田葡萄花油藏成藏控制因素研究

Controlling Factors of Hydrocarbon Accumulation in Putaohua Reservoir of Puxi Oilfield

葡西油田是长垣以西地区葡萄花油层规模最大、物性最差、埋藏最深、油水最复杂的油藏。为了葡西油田全面投入开发,提高外围油田的动用程度,本文通过实测高压物性PVT相图法、经验判别法、计算PVT相图法认为研究区的油藏为含溶解气的油藏。通过断裂和蒸发分馏对成藏的控制因素分析,表明研究区油藏与凝析气藏同源,油气藏经历了成藏-破坏-再成藏的复杂过程,油、气、水层分布受控于早、晚期断层和异常高压的分布等因素。油藏以油水同层为主,凝析气藏分布于岩性上倾尖灭形成的圈闭部位,规模很小,仅为单砂体内的小气顶。

Putaohua reservoir in Puxi oilfield,with the worst properties,is the largest,deepest and most complex reservoir in the west of Daqing.Aiming to develop the Puxi oilfield,improving the level of the external field usage,we used PVT properties in high-pressure phase diagram method,experience discrimination and PVT phase diagrams to concluded that the reservoir in this area is the reservoir with dissolved gas.By the research of faulting,evaporation fractionation effect on hydrocarbon accumulation,the results suggested that the gas condensate reservoir come from common reservoir.Reservoir has experienced a complex process which has been accumulated and destroyed,and accumulated again.The distribution of oil,gas and water is controlled by the distribution of early and late faults,abnormal pressure and other factors.The main reservoir is oil-water layer.Gas condensate reservoir located in the lithologic traps which were formed by pinch upward.