Karst - this is serious (25 photos) (22 photos)

Ground underfoot seems solid and stable, but sometimes the ground suddenly collapses, forming deep craters. Sinkholes are ubiquitous and can reach 600 meters in depth or diameter. Their causes are varied: the collapse of land above the underground voids or mine, soil erosion due to water pipe break or heavy rainfall, leaching of soluble rocks groundwater, and so on. This collection includes photographs of the largest sinkholes formed as a result of natural geological processes and human activities. (25 pictures)














































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