峰林平原区岩溶塌陷特征与抽水诱发塌陷的预防——以广西来宾小平阳地区为例

KARST COLLAPSE AND PREVENTION OF PUMPING INDUCED COLLAPSE IN PEAK FOREST PLAIN-A CASE STUDY IN XIAOPINGYANG, LAIBIN, GUANGXI

广西来宾小平阳地区为一典型的亚热带峰林平原地貌区，其间粘性土、砂性土厚０～１０ｍ，岩溶发育。截至目前为止，区内因自然和人为因素而引起的塌陷有１９处，共５１个塌坑。除马槽山基岩自然塌陷为巨型塌陷外，其余均为土层塌陷且规模均较小，塌陷群的影响面积都不足１ｋｍ２。岩溶塌陷的平面形态一般受基岩开口溶洞（隙）形态的控制；剖面形态除受开口洞隙形态控制外，还受土层厚度及其岩性的影响。塌陷的时空分布特征与自然地质环境、水文气象和人为因素的影响及其变化有关。对于抽水诱发塌陷的预防。

Xiaopingyang in Laibin County, Guangxi, is located in a typical subtropical peak forest plain where top soil is very thin and mainly clay or sandy soil, both surface and underground karst is extensively developed. Total 19 karst collapses including 51 collapse pits have been reported. Except for a large scale bedrock collapse in Macaoshan, all the others belong to small scale soil collapses with an effected area less than 1 km 2 each. The lateral forms of collapses are usually controlled by the openings of underlying bedrock caves or crevices. Whereas their vertical sections are affected by the thickness and property of overlying soil. Their occurrence and distribution are dependent upon natural geological, hydraulic and climatic conditions, as well as human activities. Collapse induced by karst groundwater pumping can be prevented by rational distribution of extraction wells, water table falldown control under a certain extent and other measures.