高邮凹陷复杂断块油气藏油气运聚机理研究

Study on hydrocarbon migration and accumulation mechanism in complex fault-block reservoir of Gaoyou Sag

王洪江

Wang Hongjiang

中国地质大学（北京）地球科学与资源学院，北京 100083

School of Geosciences and Resources, China University of Geosciences, Beijing 100083, China

复杂断块盆地油气分布复杂，控制因素多样，为研究其运聚机理带来了很大的障碍。通过解剖真武油田油气运移路径及成藏期次，依据实际地质资料设计实验模拟油气运聚过程，最后对比分析实际地质模型与实验过程，认为断层相对封闭即断层输导性能小于两侧砂体，这与实际地质情况吻合。在断层相对封闭作用下，无论是幕式充注还是稳态充注，各砂层都有充注机会，且具有下部砂体优先于上部砂体的特征。如果充注强度足够高，上下多层砂体都可以成藏，形成纵向多层含油、横向上叠合连片的局面。断层相对封闭作用从不同方面揭示了复杂断块油气藏油气运聚机理和分布规律，为勘探方向和勘探决策提供了有力依据。

Complex hydrocarbon distribution and various controlling factors bring the great difficulty to study the mechanism of hydrocarbon migration and accumulation in complex fault-block reservoir. Through the analysis of hydrocarbon migration path and hydrocarbon accumulation stage, the experiment is designed in terms of actual geological data and the process of hydrocarbon migration and accumulation is simulated. It is believed that the capacity of transporting hydrocarbon of sealed fault is less than that of both sides of sandbody, which is consistent with actual geological situation, compared the actual geological model and experimental process. Because of the sealing process of fault, there is the injection opportunity for every sands whether episode injection or stable-state injection, with the lower sandbody being prior to the upper sandbody. The hydrocarbon reservoir can be formed for the upper and lower multiple sandbody if the injection strength is high enough, which can form the multiple oil-bearing series vertically and the superimposed continuous reservoir laterally. Sealing process of fault reveals the mechanism of migration and accumulation and distribution of hydrocarbon from different aspects, which provides a basis for guiding the petroleum exploration direction and making the exploration decision.