Initiation mechanism and movement characteristics of the catastrophic Caotan landslide triggered by the Ms 6.2 Jishishan earthquake on 18 December 2023 in Gansu, northwestern China
- 1Institute of Geomechanics, Chinese Academy of Geological Sciences
- 2Qinghai 906 Engineering Survey and Design Institute Co., Ltd
Abstract
Background On 18 December 2023 (CST), an Ms 6.2 earthquake struck Jishishan County, Gansu Province, northwestern China. The catastrophic Caotan loess landslide–mudflow, located approximately 14.8 km from the epicenter, was triggered simultaneously. Because the landslide caused extensive damage, affected a large area, and resulted in substantial casualties, we conducted a detailed investigation comprising field surveys, UAV surveys, borehole drilling, trench observations, and in situ tests. We analyzed the topography, geological setting, hydrological conditions, and geometry of the landslide. Results Strong seismic shaking initiated slope failure in the source area. The displaced mass rapidly transitioned into a mudflow and traveled down the Qijia Valley, producing an unusually long runout over gentle terrain. We discuss the probable initiation mechanism, the transition process from sliding to flow, and the movement characteristics using evidence from the field investigation. Conclusions We identify the principal factors controlling the initiation and long-runout movement of the Caotan landslide. These findings provide insight for mitigating similar hazards in northwestern China and other loess-covered regions worldwide.
Related
- Seasonal variation of earthquake source characteristics of the long-duration Palghar swarm, western India
- Contrasting offshore and onshore strong ground motions from the 2025 Mw 7.6 Aomori subduction interface earthquake: Characteristics and model evaluation
- Investigations on the initiation mechanism of rainfall-induced loess landslides driven by sinkhole-assisted seepage: a case study in Qinghai, China
- Initiation mechanism of irrigation-induced retrogressive loess landslides on the South Jingyang Tableland, China
- Evaporation cracking characteristics and mechanism of silt improved by microbial-induced calcium carbonate precipitation
BibTeX
@article{li2026initiation,
title = {{Initiation mechanism and movement characteristics of the catastrophic Caotan landslide triggered by the Ms 6.2 Jishishan earthquake on 18 December 2023 in Gansu, northwestern China}},
author = {Ran Li and Ping Sun and Shuai Zhang and Kangyun Sang and Chaoying Ke and Zhanxi Wei and Tao Wang and Yun Li},
journal = {Geoenvironmental Disasters},
year = {2026},
month = oct,
doi = {10.1186/s40677-026-00416-1},
url = {https://doi.org/10.1186/s40677-026-00416-1},
note = {CC BY},
}
RIS
TY - JOUR
TI - Initiation mechanism and movement characteristics of the catastrophic Caotan landslide triggered by the Ms 6.2 Jishishan earthquake on 18 December 2023 in Gansu, northwestern China
AU - Ran Li
AU - Ping Sun
AU - Shuai Zhang
AU - Kangyun Sang
AU - Chaoying Ke
AU - Zhanxi Wei
AU - Tao Wang
AU - Yun Li
PY - 2026
DA - 2026/10/25
JO - Geoenvironmental Disasters
DO - 10.1186/s40677-026-00416-1
UR - https://doi.org/10.1186/s40677-026-00416-1
AB - Background On 18 December 2023 (CST), an Ms 6.2 earthquake struck Jishishan County, Gansu Province, northwestern China. The catastrophic Caotan loess landslide–mudflow, located approximately 14.8 km from the epicenter, was triggered simultaneously. Because the landslide caused extensive damage, affected a large area, and resulted in substantial casualties, we conducted a detailed investigation comprising field surveys, UAV surveys, borehole drilling, trench observations, and in situ tests. We analyzed the topography, geological setting, hydrological conditions, and geometry of the landslide. Results Strong seismic shaking initiated slope failure in the source area. The displaced mass rapidly transitioned into a mudflow and traveled down the Qijia Valley, producing an unusually long runout over gentle terrain. We discuss the probable initiation mechanism, the transition process from sliding to flow, and the movement characteristics using evidence from the field investigation. Conclusions We identify the principal factors controlling the initiation and long-runout movement of the Caotan landslide. These findings provide insight for mitigating similar hazards in northwestern China and other loess-covered regions worldwide.
SN - 2197-8670
ER -