Late Quaternary slip rate of the Aksay segment and its rapidly decreasing gradient along the Altyn Tagh fault

Abstract

AbstractConstraining the fault slip rate on a fault can reveal the strain accumulation and partitioning pattern. The Aksay segment, the eastern segment of the Altyn Tagh fault, as the starting area where the slip rate of the Altyn Tagh fault decreases, is a strain partitioning zone. The spatial and temporal distribution of its fault slip rate is of great significance to clarify the strain-partitioning pattern of the eastern Altyn Tagh fault. In this study, we determined the slip rates at four sites along the Aksay segment. The results demonstrated that the slip rate decreases dramatically, with an overwhelmingly high slip gradient of ∼9.8 mm/yr/100 km (a 9.8 mm/yr reduction of slip rate occurs over a distance of 100 km) within a distance of ∼50 km. The slip rate gradient along strike at the Aksay segment is four times that of the Subei segment to the eastward termination of the Altyn Tagh fault. Our results indicate that the slip rate gradient along the Altyn Tagh fault is not uniform and decreases eastward with variable slip rate gradients on different segments, resulting in the uplift of the mountains oblique to the Altyn Tagh fault.