The uplift area of the Enping Sag is far away from the center of hydrocarbon-generation where the hydrocarbon is mainly accumulated via lateral migration. The model of cross-fault accumulation was proposed based on the characteristics of shallow faults, such as shallow burial depth, late activity and weak sealing ability, which has been used as guide for the exploration in the uplift areas and led to the discovery of a number of commercial oil fields. In this paper, the major accumulation features of the shallow subsurface of the northern and southern Enping Uplift areas have been analyzed. The model and genetic mechanism of hydrocarbon in shallow lateral migration across undiagenetic faults also have been elaborated. It is concluded that weak diagenesis is the key factor which limits oil column height and strong hydrocarbon injection. Fault-channel sand body-structural ridge form the stratigraphic framework. The balance between hydrocarbon charging intensity and trap convergence ability controls the enrichment of the traps on the oil migration path, while the difference of displacement pressure between faults and the reservoir controls the distribution of hydrocarbon in the process of its migration. The accumulation model of lateral cross-fault migration is a useful guideline for shallow petroleum exploration. © 2021, Science Press. All right reserved.
