How is the sinkhole formed! Why is there a sinkhole?

What questions do you ask all day? . . . . . . . . . . . . The causes of tiankeng are mostly divided into two types, most of which are subsidence type (Tiankeng Group in leye county, Guangxi, etc. ) and rare erosion type (Chongqing Wulong Houping erosion tiankeng group, etc. ). Tiankeng is a natural geological phenomenon. 80% of sinkholes are caused by groundwater activities. The sinkhole may be formed when the local groundwater carries quicksand to a low pressure place, or when the local groundwater erodes limestone, or when the groundwater level drops, it causes a funnel. The basic principle of tiankeng is that the crust part can't bear its own weight and collapses. This kind of sinkhole is especially common in mining areas. In the mining areas with mining height of 10~ 15 meters in southern Shandong and northern Anhui, it is very common to have sinkholes with a depth of 7~8 meters. This sinkhole is the result of artificial mining. That is to say, the earth's crust collapses caused by artificially emptying a volume underground. There are also many large sinkholes in Castel landform in Guangxi, Yunnan, which is the attraction of Castel. morose

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