Late Quaternary slip rate variation of the Kuyake to Tula segment of the Altyn Tagh fault and its regional tectonic implications

Abstract

Quantifying strike-slip rates along the Altyn Tagh fault (ATF) is critical for understanding Tibetan Plateau deformation. Previous studies focused mainly on areas east of 85°E, leaving slip rates and spatial variations in the western ATF poorly constrained. We investigate Late Quaternary slip rates along the Kuyake-Tula segments through field surveys, UAV photogrammetry, LaDiCaoz_v2 displacement modeling, and optically stimulated luminescence(OSL) dating. The AK Tagh segment exhibits a left-lateral strike-slip rate of ∼17 mm/a, while the Yousubale Tagh segment shows reduced rates of ∼10 mm/a laterally. This 40 % slip rate decrease reflects fault segmentation and structural transformation mechanisms. Kinematic vector analysis reveals that the reduction in slip rates in the Yousubale Tagh segment is jointly regulated by the shortening of the North Altyn Tagh fault (∼3 mm/a) and Qimantage fault zone and Kumkol anticline (∼8.16 mm/a). This study supports the “the imbricated thrusting transformation-limited extrusion model” and provides new evidence for the segmented activity of the Altyn Tagh fault and its coordinated evolution with regional structure.