四川锦屏落水洞岩溶地下水示踪

TRACER TEST TO KARST GROUNDWATER IN LUOSHUIDONG AREA,JINPING,SICHUAN

在岩溶水文地质调查的基础上,进行钼酸铵示踪试验。结果显示,落水洞沟水在落水洞附近进入地下含水层后,沿T2z/T1岩层接触边界或断层(F 6-F 9)分成两股,一股向东排向磨房沟东大理岩地下水排泄带,另一股向南转西南、西北分别排向景峰桥-牛圈坪沟段西雅砻江河床。磨房沟泉流域地下水向西袭夺造成该流域西部地表、地下分水岭不一致。而西雅砻江示踪段构造裂隙发育,地下水主要沿具有双重含水介质(稀疏裂隙和少量岩溶管道)的大理岩流动,天然条件下地下水流动缓慢。其中的局部大型溶蚀裂隙或串珠状溶洞成为主要地下水储水空间,其疏干性突水对工程施工有一定影响。

Based on karst hydrogeologic investigation, a tracer experiment to karst groundwater was carried out in Luoshuidong area, Jinping, Sichuan province. It is showed that after the Luoshuidong stream water enters the underground aquifers via sink hole, the groundwater divides into two branches along the contacting boundary of the strata T2z/T1 or the faults F6-F9. One flows underneath the bottom of the sandstone （Ts） eastward to the marble discharge area on the east Mofanggou, and the other flows southward and then turns southwestward and northwestward along the faults （F6-Fg） to the west Yalongjiang riverbed in Niujuanpinggou and Jingfengqiao area. The watershed divides of Luoshuidong and Mofanggou basins are quite different from those underground due to the ground capture of Mofanggou Big Spring. Groundwater in Luoshuidong area mainly moves slowly through marble aquifer media （that is of double water containing character, includes sparse crannies and few karst conduits）. Among them, the major groundwater storage space consists of locally large dissolved crannies and string of beads-shaped caves, which is of dredge up feature and should be considered in the canal-digging.