The late Quaternary activity of the Yadu Fault in Guizhou, China

The Yadu Fault (YDF), a critical component of the Yadu-Ziyun Fault system along the southwestern boundary of the South China block, plays a significant role in understanging regional deformation mechanism and kinematic characteristics. Through integrated methodologies including field investigations, high-precision remote sensing image interpretation, UAVs Photogrammetry, high-density electrical profiling, and OSL Dating, this study reveals the following key findings: The Yadu Fault exhibits a northwest-striking with a dextral strike-slip motion, which cumulative displacements of 31.7–74.1 m observed across multiple gullies. The fault truncates Late Pleistocene strata dated at 34.0 ± 5.0 ka, confirming its activity during the Late Quaternary. The horizontal slip rate is estimated about 1.3 mm/a, classifying the Yadu Fault as a Late Pleistocene active structure. These results provide essential constraints for seismic hazard assessments and tectonic evolution studies in the region.