Study on the relationship between multi-stage strike-slip mechanism and basin evolution in Fangzheng fault depression

Fangzheng fault depression is controlled by the northern of the Tan-Lu fault zone. It undergoes multi-stage strike-slip, extrusion modification, and erosion of the thermal uplift, forming a tectonic pattern of uplifts connected with sags. Through the regional dynamic analysis, the study of the activity law of the western Pacific plate has clarified the formation and transformation of the regional tectonic stress field. Under the background of the multi-stage of the strike-slip mechanism in the northern part of the Tan-lu fault, the Fangzheng fault depression has a characteristic of the “left-lateral strike-slip pull-apart basin, right-lateral strike-slip extrusion transformation.” According to the difference of the strike-slip, the Fangzheng fault depression has divided into two parts: the East fault depression and the West fault depression. The seismic data, seismic attribute analysis, and geological modeling techniques have applied to analyze the two fault depressions, the East fault depression has actively controlled by the strike-slip activity, and the structure is complex. The seismic data quality is poor; the structure of the West Fault Depression is the opposite and structural characteristics of asymmetrical difference strike-slip in the East and West fault depressions. Interpretation of seismic sections through a slippery background, the strike-slip attributes of the whole fault depression from south to north are segmented, and the strike-slip mechanism from east to west is different. Under the control of the multi-stage strike-slip mechanism, the Fangzheng fault depression is divided into six stages of strike-slip evolution, corresponding to the six different stages of the strike-slip control basin, the formation process of the asymmetric difference strike-slip fault basin is clarified, which provides a reference for the study of the strike-slip pull-apart basin with multi-stage structure