Northern and Central Segments of Shunbei No.5 Strike-Slip Fault Zone in Tarim Basin: Structural Characteristics and Spatio-Temporal Evolution Process

The northern and central segments of the Shunbei No. 5 strike-slip fault zone are characterized by multi-stage superimposing deformation along with the strike and vertical. Because of the complex structural deformation, it is challenging to understand the deformation and then reconstruct its spatio-temporal evolution process. Based on high-precision 3D seismic data, through precise structural interpretation and analysis of seismic profiles, as well as structural back-stripping restoration, in this study it conducted a more comprehensive study on the structural deformation and multi-stage evolution process of the fault zone, the conclusions are as follows. (1) In the deep sections (Sinian to Middle Ordovician), the principle deformation zone of the fault is characterized by stress-strain localization along with the strike and in the vertical. (2) In the upper sections (Upper Ordovician to Carboniferous), there are transpressional folds and three sets of en echelon normal faults. The three sets of en echelon normal faults are superimposed vertically and formed in different periods. Among them, the No. 1 and No. 2 en echelon normal faults formed simultaneously with the transpressional anticlines. (3) In general, the northern and central segments of the Shunbei No. 5 strike-slip fault zone had experienced five stages of structural evolution processes, they are the initial rupture period (in phase I of the middle Caledonian), structural embryonic period (the deposition period of the Sangtamu Formation), intense structural deformation period (the deposition period of the Kepingtage Formation), structural inheritance period (from the end of the Early Silurian to the Middle Devonian), and structural inversion period (in Permian). © 2023 China University of Geosciences. All rights reserved.