Sinkholes in karst mining areas in China and some methods of prevention

摘要

Mining of coal, lead and zinc, gold, and iron oredeposits in karst areas has been closely associated with sinkholesin China. Surface collapse causes an increase in mine waterdrainage and the possibility of major water inflow from karstaquifers, which threatens the environment in mining areas andendangers the mine safety. A combination of factors includingsoil weight, buoyancy, suffusion process and vacuum suction cancontribute to the sinkhole formation. The key measures toprevent sinkholes in mining areas are to control the amount ofmine drainage, reduce water level fluctuation, seal-off karstconduits and subsurface cavities in the overlying soil, preventwater inflow, and/or to increase gas pressure in the karst conduits.