西北地质2024，Vol.57Issue(2)：220-229,10.DOI:10.12401/j.nwg.2024015
甘肃积石山地震液化型泥流特征、成因及其对黄河上游盆地地震次生灾害风险评估的启示
Characteristics and Initiation Mechanism of the Liquefied Mudflow Caused by Jishishan Earthquake in Gansu Province and Its Enlightenment on Risk Assessment of Secondary Earthquake Disasters in the Upper Yellow River Basin
摘要
Abstract
At 23:59:30 Beijing time on December 18,2023,an Ms 6.2 shallow earthquake occurred in Jishis-han County,Linxia Prefecture,Gansu Province.The earthquake triggered a coseismic giant mudflow in Zhongchuan Township,Minhe County,Qinghai Province,resulting in a catastrophic event.Research methods such as on-site investigation,drone photogrammetry,sampling,and experimental testing were adopted to ana-lyze the development characteristics and causes of this mudflow hazard.The results indicate that:① The mud-flow has typical planar characteristics of valley-type debris flow,with clear boundaries between the formation area,the circulation area,and the accumulation area.The main source of the mudflow is the piedmont pluvial silty clay.② Earthquake provides initial momentum,while melting snow,winter irrigation of farmland,and low temperature freezing raise the local groundwater level,which are the main triggering factors of the mudflow.The topographic slope provides subsequent kinetic energy,and the geological lithology provides condition for vibrational liquefaction,which are the inherent causes of the mudflow.③ There are lateral and bottom scraping effects in the process of mudflow transportation,especially in the three flow direction changing areas,where lat-eral scraping and local accumulation are significant.Eventually,it quickly flows into Jintian Village and Caotan Village at the mouth of the gully.The results obtained can provide ideas and theoretical basis for the risk assess-ment of secondary disasters caused by earthquakes in the Guanting Basin and even the sedimentary basins in the upper reaches of the Yellow River.关键词
积石山地震/振动液化/雪融/冬灌/粉质黏土/泥流灾害Key words
Jishishan earthquake/vibrational liquefaction/snow melting/winter irrigation/silty clay/mudflow hazard分类
天文与地球科学引用本文复制引用
刘港,贾俊,张戈,洪勃,董英,裴赢,薛强,高波..甘肃积石山地震液化型泥流特征、成因及其对黄河上游盆地地震次生灾害风险评估的启示[J].西北地质,2024,57(2):220-229,10.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),陕西省自然科学基金青年项目(2023-JC-QN-0288),中国地质调查局西安地质调查中心主任基金项目(XACGS-2022-04)联合资助. （42177346）
