1996年丽江7.0级地震地裂缝新发现

New Discovery of Ground Fissures in 1996 Lijiang M7.0 Earthquake

1996年2月3日云南丽江发生7.0级强烈地震,震后考察发现了广泛的地表破坏现象,主要包括地裂缝、崩塌、滑坡、地面陷落、田坎位错及地表跳石等,基本集中分布在Ⅸ度极震区范围内,但有关地震地裂缝的描述较少。近期,在进行大具盆地野外地质调查时发现1处新的地裂缝,位于云南丽江7.0级地震微观震中附近,具体位置为大具盆地南部峨嵋子村西北、将台河二级阶地上,长约35 m,总体走向350°左右,最窄处宽约0.3 m,最宽处表现为凹陷坑,宽约2.2 m。经当地村民确认,新发现的地表地裂缝是1996年丽江地震形成的,该地裂缝在震后考察时未提及。

On February 3,1996,a strong earthquake with M7.0 occurred in Lijiang,Yunnan Province.After the earthquake,extensive surface damage phenomena were found,mainly including ground fissures,collapses,landslides,ground subsidence,ridge dislocations and surface rockfalls,which were mainly distributed in the area of magnitude IX,however,there are few descriptions of seismic ground fissures.Recently,a surface ground fissure was found in the Daju Basin during the field geological survey,which is located near the micro epicenter of Lijiang earthquake with M7.0 in Yunnan.The specific location is on the second terrace of Jiangtai River in the northwest of Emeizhi village,Southem Daju Basin.The length of the surface ground fissure is about 35 m long and the overall strike is about350°.The narrowest part is about 0.3 m,and the widest part is a depression pit with a width of 2.2 m.According to the analysis,the newly discovered ground fissure was formed by Lijiang earthquake in 1996,and it was not mentioned in the investigation after the earthquake.