Rapid assessment of landslides induced by the Jishishan Ms6.2 earthquake based on Newmark model
On December 18,2023,an Ms6.2 earthquake hit Jishishan County,Linxia Hui Auton-omous Prefecture,Gansu Province.This phenomenon induced numerous geological disasters,such as landslides and collapses.The Newmark displacement prediction model was first derived from the regression analysis of ground motion records of the 2013 Minxian—Zhangxian Ms6.6 earthquake in the strong earthquake database of the Loess Plateau.Therefore,considering the vertical seismic acceleration and the influence of winter irrigation,a rapid assessment of landslide risk in the area within 100 km from the epicenter was conducted using 30-m resolution topogra-phy and a 1∶2.5 million geological map before the earthquake.Assessment results were compared with the distribution of geological disasters before the earthquake and the results of remote sens-ing interpretation and field investigation after the earthquake.The comparative results reveal that areas with low static safety factors are prone to geological disasters.The landslide risk area is mainly located within 27 km from the epicenter,where the channels and watersheds are highly developed,and the strata mainly comprise Neogene and Quaternary formations,demonstrating high similarity to the existing research results.The study demonstrates that the Newmark dis-placement method is appropriate for assessing post-earthquake landslide risk in the Jishishan area.However,the Newmark displacement method overlooks soil liquefaction,thereby underestima-ting the degree of danger of liquefaction.
万方数据
维普
