地表沉降和地陷不象地震那样,一时间地裂屋倒,灾难即临,而是缓缓沉降,短时间里,人们觉察不出,但却会成为一种大隐患。当今世界上许多著名古城或首都都在缓缓沉降。在美国有不少州,不断发生断陷事件,出现了数以百计的新“湖泊”。体斯顿 The surface subsidence and subsidence are not like those in the earthquake. When the house collapses and the disaster is on the verge of a single time, it gradually settles. In a short time, people cannot see it, but it will become a big hidden danger. Many well-known ancient cities or capitals in the world are slowly settling. In many states in the United States, there have been continuous incidents of depression and hundreds of new “lakes” have emerged. Austin