Control of the Wubao Faulted Structure over the Migration of Petroleum in the Chenbao Oilfield of the Gaoyou Depression, Jiangsu
高邮凹陷吴堡断裂构造带对陈堡油田 油气运移的控制作用

The Chenbao oilfield located in eastern Wubao fault belt comprises faulted reservoirs composed of Chen 2 block and Chen 3 block. The migration of petroleum into the reservoirs from the Liuwushe sag remains a problem unclear to researchers. An analysis of the evolution of the faulted structure in the Wubao fault zone has revealed that faults play an important role in the generation, migration and accumulation of the petroleum. The difference of maturation between the upper reservoirs and the lower reservoirs was caused by different infilling periods and different migration pathways in different epochs, which resulted from the evolution of the faulted structures. The burial history of source rocks led to different maturation degrees of petroleum in different epochs. During the evolution of the faulted structure, the pathways for petroleum migration, which were composed of faults and sandstone beds, changed from time to time, and the petroleum migrated from the source rocks into the Chenbao oilfield. It seems that the petroleum derived from the source rocks first migrated along small faults, then accumulated along the Wu 1 fault, and finally moved upwards into different reservoirs. The migration of the pe-troleum in the Chenbao area has the following characteristics: petroleum came from the same source bed but de-veloped in different periods, and it migrated along different pathways.