商·地震山崩多灾难——漫步地震五千年(3)

Shang:Earthquake landslides cause multiple disasters

商周期间的地震记载多在川西—陕甘交界地区,山体垮塌十分普遍。现代科学将之划分成4种主要形态:落石、崩塌、滑坡和泥石流,其中以地震致崩塌和滑坡的危害最大。具体地介绍了汶川、湔江、叠溪和磨西地震山崩的灾情,特别是王家岩滑坡的力学机制;分析了历史上滑坡、河流改道、堰塞湖溃坝三大次生灾害;说明在青藏高原的推挤作用下,该区岩体的反复破裂是致灾元凶。

Most of the earthquakes recorded during the Shang and Zhou Dynasties were in the West Sichuan-Shaanxi-Gansu border area,where mountain collapses were very common.Modern science has classified the phenomenon of mountain collapse into four main forms:rockfall,rock avalanche,landslide and debris flow,of which rock avalanche and landslide caused by earthquakes are the most dangerous.Specifically,we introduced the disasters of Wenchuan,Jianjiang,Diexi and Moxi earthquakes,especially the mechanism of Wangjiayan landslide,and focused on the occurrence of three major secondary disasters:landslide,river diversion and dam-break of barrier lake.It is pointed out that the site conditions of thrusting and repeated rupture on the Tibetan Plateau were the key reasons of the disaster.