From rock collapse to slide movement: a case study of the 2004 Zuojiaying Landslide

Abstract The mining process instigates the development of subsurface goaf, resulting in surface deformation and subsidence. The deformation and failure characteristics of the landslides in mining regions present a challenge to the detection and analysis of the initiation and progression mechanisms. There has been a significant focus on comprehending the complex nature and destruction associated with such geohazards, which are becoming more common and typical in the southwestern region of China. The present study showcases a compelling example of the 2004 Zuojiaying landslide in Guizhou, China, where rainfall and long-term mining activity triggered a rock collapse that transformed into a sliding event, causing 44 fatalities. A thorough field and aerial survey are conducted for the rock collapse-transformed sliding mass, further supplemented with a dynamic modeling approach to simulate the runout, entrainment, and accumulation processes of the landslide. Our work presents a comprehensive analysis and discussion of the geological condition, potential triggers, collapse mechanism, erosion characteristics, and the 3D runout evolution of the Zuojiaying landslide. Furthermore, the present study explores the significant influence of entrainment and erosion on landslide volume, mobility, and deposition, particularly in the transition from rock collapse to sliding. We have identified and outlined the stages of runout progression and landslide transformation by analyzing the entrainment over the entire runout. This study aims to highlight the significance of developing a thorough understanding of such landslide hazards in areas with comparable geological characteristics to improve geohazard management.