Application of 3D geological modeling to analyse fault-controlled hydrocarbon accumulation in complex structural zones: a case study of the northern part of Qikou Sag

The Qikou sag forming massive of fault-type oil and gasreservoirs. Based on previous achievements and data such as three-dimensional seismic data, this article analyzes the relationship between faults and petroleum and natural gas reservoirs in the northern part of Qikou sag through three-dimensional geological modeling. The results show that the faultcontrolled reservoir model in the study area can be roughly divided into four types: synthetic fault shielding oil and gas accumulation mode, antithetic fault shielding oil and gas accumulation mode, cross-fault shielding type petroleum and gas accumulation mode, and fault reactivation control secondary oil and gas accumulation mode. This 3D structural model shows that fault-controlled reservoir characteristics in the northern part of Qikou sag in three-dimensional space.