下径湖垦区岩溶塌陷成因分析及防治措施建议

Genetic Analysis and Prevention Suggestion of Karst Collapse in Xiajing Lake Reclamation Area

湖北省大冶市下径湖垦区岩溶发育,2019年3月以来发生连续塌陷。根据下径湖垦区典型岩溶地面塌陷点的地质勘查资料及水文监测数据,岩溶发育是下径湖发育地面塌陷灾害的内在原因,研究区属于覆盖型岩溶区。研究表明,下径湖垦区2019年3—6月新发塌陷是由于矿区排水(涌水)直接引发的地面塌陷。其机理为长流港北侧下径湖垦区地下水沿着F26、F6断层附近破碎带或岩溶发育区通过二期帷幕过水通道进入鲤泥湖矿区帷幕内,再经过涌水点被大量排出,造成下径湖垦区岩溶水位急剧下降,进而引发塌陷。研究区塌陷对农田、高压输电塔、港堤等造成了严重威胁,需采取综合措施进行防治。

Karst developed in Xiajing Lake reclamation area,and continuous collapse occurred since March 2019.According to the geological exploration data and hydrological monitoring data of typical karst ground collapse points in Xiajing Lake reclamation area,the karst development is the internal cause of the ground collapse disaster in Xiajing Lake reclamation area,and the study area belongs to covered karst area.The study shows that the new subsidence in Xiajing Lake reclamation area from March to June in this year is caused by the surface subsidence directly caused by drainage(water gushing)in mining area.The mechanism is that the groundwater in Xiajinghu reclamation area on the north side of Changliugang enters into the curtain of Linihu mining area through the second stage curtain water passage along the fracture zone or karst development area near F26 and F6 faults,and then is discharged in large quantities through the water gushing point,resulting in a sharp drop of karst water level in Xiajing Lake reclamation area,which leads to collapse.The collapse of the study area poses a serious threat to farmland,high-voltage transmission tower and port embankment,and comprehensive measures should be taken to prevent and control the collapse.