油气成藏期输导断裂侧向封闭油气的判别方法及其应用

为了研究含油气盆地断裂发育区油气分布规律,在油气成藏期输导断裂侧向封闭油气机理及所需条件研究的基础上,通过比较输导断裂填充物泥质体积分数与侧向封油气所需的最小泥质体积分数的相对大小,建立了一套油气成藏期输导断裂侧向封闭油气的判别方法,并将其应用于渤海湾盆地冀中坳陷霸县凹陷文安斜坡区沙河街组一、二段油气成藏期输导断裂侧向封闭油气的判别中。研究结果表明:文安斜坡区沙河街组一、二段油气成藏期输导断裂侧向封闭油气区主要分布在文安斜坡区中部,少量分布在南部和北部局部地区;沙河街组二段输导断裂侧向封闭区面积略大于沙河街组一段,有利于油气聚集成藏。这与目前沙河街组一、二段已发现油气分布相吻合,表明该方法用于判别油气成藏期输导断裂侧向封闭油气是可行的。

Discriminating method of the lateral sealing oil and gas by the transporting fault in hydrocarbon accumulation period and its application

In order to study the distribution law of the oil and gas in the fault-developed areas of petroliferous basins, based on the researches on the lateral sealed mechanism of the oil and gas by the transporting fault and its required conditions in the hydrocarbon accumulation period, and moreover by comparing the relative sizes between the shale content of the filler for transporting fault and the minimal shale content required for the lateral sealing, a set of discriminating method was established for the lateral sealing by the transporting fault in the hydrocarbon accumulation period, and furthermore it was applied in identifying the lateral petroleum sealing by the transporting fault in the accumulation period in Member Es1 and Es2 of Wen’an Slope in Baxian Sag of Jizhong Depression in Bohai Bay Basin. The study results show that the lateral sealed zone by the transporting fault in the accumulation period of Member Es1 and Es2 in Wen’an Slope is mainly distributed in the central of Wen’an Slope, and a small amount of the hydrocarbon is located in the southern and northern parts of the region;and the area of the lateral sealed zones by the transporting fault Member Es2 is slightly larger than that of Member Es1, which is conducive to the hydrocarbon accumulation. The conclusions are coincident with those of the oil and gas currently found in Member Es1 and Es2, thus suggest that the method is feasible to be applied in discriminating the lateral oil-gas sealing by the transporting fault in the hydrocarbon accumulation period.