开阳南江大峡谷岩溶地下水补径排研究

Study on recharge, runoff and drainage of karst groundwater in Nanjiang Grand Canyon in Kaiyang

贵州开阳南江大峡谷景区岩溶地下水资源丰富,为独特的岩溶峡谷喀斯特地貌,为了查明该区地下水径流特征,特开展此次研究。在野外1∶10 000水文地质调查的基础上,通过水文地质剖面,结合NaCl示踪试验以及13组地下水样的水化学离子与总溶解性固体(TDS)测试结果进行综合分析,分析研究区地下水补径排特征。结果显示:(1)区内地下水的补给主要来自于大气降水与地表水,具有就地补给、就近泉点排泄循环的特点;(2)兰家寨段地下水受构造控制强烈,火龙潭(SQ2)上升泉同时作为F2断层两盘地下岩溶水的排泄点;(3)梯子岩泉作为断裂带泉也接受顶部洼地与落水洞处地表水的补给,并且存在一条地下岩溶管道;(4)大新场-屯上段鱼梁河与白安河同时作为峡谷两岸的排泄基面,不存在水力联系;(5)坡顶上-老河沟段之间地层的凸起转折对SW向与NE向地下水具有分流作用,构成地下水分水岭并使NE向地下水向老河沟方向径流。研究成果可为该区域供水提供地质依据。

The karst groundwater resources in the Nanjiang Grand Canyon scenic spot of Kaiyang in Guizhou Province are rich, for the unique karst canyon karst landform. In order to find out the characteristics of groundwater runoff in this area, this study is launched. Based on the 1∶10 000 hydrogeological surveys in the field, we conduct a comprehensive analysis of hydrogeological profiles, combined with NaCl tracer experiments and 13 sets of groundwater samples of hydrochemical ions and total dissolved solids(TDS), and analyse the characteristics between recharge, runoff and drainage of groundwater in the study area. The results show that:(1) the recharge of groundwater in the area mainly comes from atmospheric precipitation and surface water, which has the features of recharge in situ and discharge nearby;(2) the groundwater in Lanjiazhai section is strongly controlled by structure, Huolongtan(SQ2) rising spring is also used as the discharge point of the underground karst water of the F2 fault;(3) as a fracture zone spring, Tiziyan spring also receives the supply of surface water from the depression at the top and the sinkhole, and there is an underground karst pipeline;(4) there is no hydraulic connection between Yuliang River and Bai’an River, which serve as the drainage based on both sides of the canyon in Daxinchang-Tunshang section at the same time;(5) in Podingshang-Laohegou section, the convex transition of the stratum has a distribution to the SW and NE to the groundwater, which forms the groundwater watershed and makes the NE flow to the Laohegou. The results of the study can provide a geological basis for water supply in this region.