The Kangding City in eastern Tibet is at high risk due to frequent strong earthquakes along the Xianshuihe sinistral strike-slip fault bounding the Chuandian Block to the northeast. The knowledge of paleo-seismicity recurrence along this fault system is key to the evaluation of earthquake hazards in this region; thus, more accurate paleoseismic information are required. We examined the paleo-seismicity along the Zheduotang fault in the central segment of the Xianshuihe fault system by applying the field investigation, trenching, and Quaternary dating methods (e.g., OSL and 14C). Field observations found ～8.5 m offset of stream by sinistral slip along the Zheduotang fault. We trenched the central fault zone of the Zheduotang fault and found that the colluvial wedges and five buried, discontinuous, A-soil horizons progressively have been offset in the shallow graben on the SW-side of the main fault indicative of the paleo-earthquakes. The dating results of OSL and 14C, in line with existing data, enable us to establish the paleo-seismic history of the Zheduotang fault. It shows at least eight surface ruptures in the last 7500 years identified from displaced buried soils, colluvial wedges and terraces. Our study reveals ～100 years minimum paleo-earthquake recurrence, suggesting potential large earthquakes in the Kangding area in the future.

Guifan Chen;Mervin Bartholomew;Demin Liu;Kai Cao;Minxuan Feng;Dun Wang

School of Earth Sciences,China University of Geosciences,Wuhan 430074,China;Three Gorges Geotechnical Consultants Co.,Ltd.,Wuhan 430074,China;Department of Earth Sciences,University of Memphis,TN 38152,USA;Xi'an Center of Geological Survey,China Geological Survey,Xi'an 710054,China

地球科学学刊（英文版）

[1]Guifan Chen;Mervin Bartholomew;Demin Liu;Kai Cao;Minxuan Feng;Dun Wang-.Paleo-Earthquakes along the Zheduotang Fault, Xianshuihe Fault System, Eastern Tibet:Implications for Seismic Hazard Evaluation)[J].地球科学学刊（英文版）,2022(05):1233-1245

Zheduotang,Kangding,Chuandian,paleoseismic,trenching,trenched

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