甘肃临夏积石山县6.2级地震地质灾害发育特征及危险性评价
Development Feature and Risk Assessment of Geological Hazards Caused by the Ms 6.2 Earthquake in Jishishan County,Linxia,Gansu Province
高波 1董英 1贾俊 1薛强 1武文英 1李林 1王涛 1刘港 1江睿君1
作者信息
- 1. 自然资源部黄土地质灾害重点实验室,中国地质调查局西安地质调查中心,陕西 西安 710119
- 折叠
摘要
2023年 12月 18日 23时 59分,甘肃省临夏州积石山县发生Ms6.2级地震,诱发了大量崩滑地质灾害,严重威胁人民生命财产安全.基于震区现场实地调查成果,开展地震诱发加剧地质灾害的发育特征、危险性评价研究,提出防灾减灾措施建议.根据实地调查统计,此次地震后新增地质灾害隐患点 64处,加剧的地质灾害隐患点有 63处.新增和变形加剧的隐患点以崩塌为主,滑坡次之;规模等级以小型为主,中型次之.崩滑地质灾害主要集中在黄土丘陵区,以黄土陡坎地带切坡建房、切坡修路为主.利用GIS技术的加权信息量法评价积石山县域地质灾害易发性.结果显示,高易发区、中易发区、低易发区、非易发区占比分别为 5.45%、9.83%、32.70%和52.02%,其中高易发区主要分布在积石山东部黄土丘陵区的山梁地带.基于区域地质灾害易发性评价,开展地震活动断裂、地震动分布以及不同降雨工况条件(10年、20年、50年、100年一遇)下积石山县域地质灾害危险性评价.结果显示:100年一遇极高危险区较 10年一遇极高危险区的增幅最大为 18.26%,说明未来区内遭遇极端降雨会显著提高区内地质灾害危险程度.研究认为,积石山地震地质灾害后效应将增强,未来崩塌、滑坡发生频次升高,地质灾害易在降水、冻融条件下形成,需针对性地采取防控措施,有效降低其威胁程度.
Abstract
On December 18,2023 at 23:59,an Ms6.2 earthquake occurred in Jishishan County,Linxia Prefec-ture,Gansu Province,triggering a large number of landslides and geological disasters,seriously threatening the safety of people's lives and property.This article is based on the results of on-site investigations in earthquake prone areas,conducting research on the development characteristics and risk assessment of geological disasters induced by earthquakes,and proposing suggestions for disaster prevention and reduction measures.According to on-site investigations and statistics,there are 64 new geological hazard points added after this earthquake.There are 63 potential geological hazards that have intensified.The main hidden danger points of newly added and in-tensified deformation are landslides,followed by landslides;The scale level is mainly small,followed by medi-um.Landslide geological disasters are mainly concentrated in loess hilly areas,with the main focus on building houses and roads by cutting slopes in steep loess slopes.The weighted information method based on GIS tech-nology was used to evaluate the susceptibility of geological disasters in Jishishan County.The evaluation results showed that the proportions of high susceptibility areas,medium susceptibility areas,low susceptibility areas,and non susceptibility areas were 5.45%,9.83%,32.70%,and 52.02%,respectively.The high susceptibility ar-eas were mainly distributed in the mountain ridge area of the loess hilly area in the eastern part of Jishi Moun-tain.On the basis of regional geological hazard susceptibility assessment,a geological hazard risk assessment of Jishishan County was conducted based on seismic activity faults,seismic motion distribution,and different rain-fall conditions(10 year,20 year,50 year,100 year return period).The evaluation results showed that the maxi-mum increase in the 100 year return period extremely dangerous area compared to the 10 year return period ex-tremely dangerous area was 18.26%,In the future,encountering extreme rainfall in the area will significantly in-crease the risk of geological disasters in the area.Research suggests that the post earthquake effects of geologi-cal disasters in Jishishan will be enhanced,and the frequency of landslides and collapses will increase in the fu-ture.Geological disasters are prone to form under precipitation and freeze-thaw conditions,and targeted preven-tion and control measures need to be taken to effectively reduce their threat level.
关键词
地震/地质灾害/发育特征/危险性评价/甘肃积石山Key words
earthquake/geological hazards/developmental feature/risk assessment/Jishishan in Gansu引用本文复制引用
基金项目
国家自然科学基金项目(42177346)
中国地质调查局项目(DD20230443)
&&(DD20221739)
出版年
2024
国家科技期刊平台
NSTL
万方数据