Characteristics and Mechanisms of Sand Liquefaction in January 7,2025 Dingri MS 6.8 Earthquake
Li Zhichao
Wu Zhonghai
Han Shuai
Gao Yang
Huang Ting
Fan Fuxin
Tian Tingting
Lu Shiming
Abstract：Sand liquefaction is one of the main forms of post-earthquake disasters,so it is of great significance to conduct a detailed surface survey of the distribution patterns and development characteristics of sand liquefaction after an earthquake.To reveal the characteristics of sand liquefaction caused by the Dingri earthquake,detailed remote sensing interpretation and field investigation were carried out in the Dingri area after the earthquake,and the following results were obtained:(1)During the MS6.8 Dingri earthquake on January 7,2025,sand liquefaction was observed in the southern Pengqu Valley,along the shores of Dingmu Co in the central area,and on the southeast side of Kongmucuo in the northern region,which suggests the formation of a widely distributed liquefied sand layer in the strata during this earthquake.In this event,ground failures caused by sand liquefaction along both banks of the Pengqu River and on the east shore of Dingmu Co were mainly characterized by lateral spreading.In contrast,ground failures in the riverbed of Pengqu,the edge of the alluvial fan on the east shore of Dingmu Co,and the southeast side of Kongmucuo were dominated by liquefaction-induced sand dunes.(2)Field observations and analysis of the tectonic stress field suggest that the sand liquefaction deformation in this earthquake underwent a dynamic developmental process.Under the influence of tectonic stress and gravity,north-south oriented tensional fractures formed.The sand liquefied due to the librations,and some liquefied material was ejected along these north-south fractures,resulting in lateral spreading due to the gentle slope.Blocks on the surface collided and compressed with each other.In some locations,intense compression and collision led to the formation of east-west oriented tensional fractures,through which liquefied material surged out,forming nearly east-west oriented linear liquefaction sand dunes.
Keywords：Dingmu Co faultMS6.8 Dingri earthquakesand liquefactionliquefaction sand dunesearthquakeshazards
Publication Date：2025-05-30
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：12( 1830-1841 )