Study On The Characteristics Of Strike-slip Faults In The North Section Of No.5 Shunbei And Its Controlling And Storage Effect

The Shunbei 5 fault zone is located in the Shuntoguole low uplift of the Tarim Basin and is dominated by Ordovician carbonate reservoirs.Among them,the fracture-cave reservoir controlled by the fault developed at the fault overlap is generally called the fault zone reservoir,which is currently a hot spot in the field of ultra-deep carbonate exploration in Shunbei Oilfield.Therefore,it is of great significance to study the characteristics of fault development,to characterize the internal structure of fault overlapped sections,and the reservoir formation patterns of different types of fault overlapped sections,to implement favorable zones,optimize well deployment,and focus on high production targets in Shunbei area.Based on the theoretical guidance of structural geology and carbonate reservoir geology,this paper carried out three-dimensional seismic interpretation,drilling calibration,reservoir analysis,etc.,and studied the fault development characteristics and formation of the northern section of the No.5 strike-slip fault zone in Shunbei Storage mode.On the basis of fine three-dimensional seismic interpretation,the method of combining discontinuous profile recognition with multiple attribute plane characterization was used to analyze the internal structural features of the fault overlap.The strike-slip fault in the north section of No.5 Shunbei is divided into 7 planes in the squeezing uplift section,3 pull-down sections,and 6 translational strike-slip sections.Various typical examples were selected to characterize the phenomena,and the fault development styles,internal structural characteristics,and the spatial combination of faults of different types of overlapping sections were clarified.On this basis,based on the various theoretical models proposed by the predecessors for the segmental deformation mechanism of strike-slip faults,combined with the geological background of the study area,starting from the analysis of the difference in the segmented stress field of strike-slip faults,we discuss Developmental model and cause mechanism.Establish geological models for the development of different strike-slip faults in the Shunbei area,and analyze the elements of the fault development model in detail.Through well-seismic calibration,full use of information such as drilling / logging / logging data,imaging logging and core drilling,the seismic response characteristics of fault zone reservoirs were identified on the earthquake,which were summarized into two types and three types: one type It is an anomalous seismic reflection wave at the interface.In the squeezing uplift,it is mostly anomalously broken in the interface's in-phase axis,and it usually shows an abnormally curved uplift in the pull-off descent.The other category is inside anomalies,including "beaded" strong reflections and chaotic reflections in the weak reflection background.Summarized the distribution rule and reservoir forming mode of the fault zone of the strike-slip fault overlap zone.Due to the different development patterns of faults,the distribution of fault zone reservoirs under their control also has obvious differences.The largest main section is developed in the middle of the squeezing uplift section,and the pull-down section is composed of the main boundary section on both sides and the secondary section formed in the middle of the later period.The development of the fault zone reservoir is asymmetric on the left and right sides of the main section,and the main body is distributed on the side where the formation is more deformed and the fault is more active.