The Controlling Effect Of Faults On Hydrocarbon Accumulation In The Yueman Block Of Halahatang Oilfield

The Yueman block in the Halahatang Oilfield is a large Ordovician marine carbonate reservoir located in the Tarim Basin.With the deepening of exploration and development,the large-scale and well-defined parts are gradually reduced,which requires a refined interpretation of the strike-slip fault in the study area.The characteristics of strike-slip fault are complex and difficult to identify.Due to the poor quality of seismic data in the study area,the seismic data volume is processed by using the structure-oriented filtering technique based on inclination control,and then the coherent data volume is produced.Good results are obtained,and the fracture image becomes clear.In order to explain the fractures in a refined way,the coherent surface maps of the main strata are extracted from shallow to deep,and the flat is combined with section to define the characteristics of the strike-slip fault.Through the analysis of seismic data,linear structure,feather structure,and horsetail structure are developed on a plane,and upright structure,flower structure,semi-flower structure,and negative flower structure are developed on the section.According to the horizon where the fracture is broken up,the strike-slip fault in the study area is divided into three phases: the middle and late Caledonian and Hercynian phases.Through the analysis of core and thin slice,the relationship between faults and the development of carbonate karst reservoirs is summarized.The fractures have improved the original dense carbonate reservoirs.Fracture is a favorable channel for oil and gas transport and migration,and the induced fracture zone is also a good reservoir.Moreover,the fault also controls the enrichment of oil and gas.The reservoirs of the Ordovician Yijianfang Formation and Yingshan Formation are distributed along the fault zone;different types of fault control oils are different,and the oil and gas accumulation on the main fault is better than the branch fracture;oil control in different sections of the fault is also different,and reservoir development and oil and gas enrichment in the feather strikeslip section are significantly better than the linear section.