Field Survey of the Zhenxiong Landslide on January 22,2024 in Yunnan Province,China
At 5:51 a.m.on January 22,2024,a catastrophic landslide struck Liangshui village,Tangfang town,Zhenxiong county,Zhaotong city,Yunnan province,China,resulting in 44 casualties at two Sub-Village at Hexing and Heping.A emergency team was organized to examine the genesis of the landslide using on-site investigation,UAVs aerial photography and remote sensing interpretation.(1)The Zhenxiong landslide was categorized as a small-scale geo-catastrophe,with sliding mass volume about 118 800 m3,but badly led to 44 deaths.(2)Prior to the occurrence,the original slope body developed a density of joint fractures up to 1.4/m,and weathering cross-sections were found in up to 60%of stacked rocky screes,suggesting before the slope failure there had been a critical stable state.(3)It is quite evident that the action of low-temperature frost heaving on unstable slope ultimately triggered the landslide.Three factors,the ponding/infiltrating at the rear edge of the slope shoulder,the interbedding stratum of stone-mudstone and the persistent low-temperatures ahead of the sliding laid the foundation for the catastrophe.The occurrence of such a small-scale landslide but severe consequence occurring in winter is highly unexpected,and it needs to be given high scientific concern.
the Zhenxiong"1·22"Landslideponding/infiltrating at slope shoulderlow-temperaturefrost heaving