鄂西南水牯洞地下河越流袭夺补给成因分析

Analysis on the Causes of Underground River Interbasin Capture and Recharge of Shuigu Cave in Southwest Hubei Province

通过近年来实施的鄂西南岩溶地区1∶5万水文地质调查,发现区内一些地下河按常规确定的汇水面积与其出口流量不适应的情况,以水牯洞地下河为例,采用水文地质测绘、示踪试验等综合调查技术手段,经分析确认,地下河出口流量大、汇水面积小的原因有二个:一是地表水跨流域越流补给,二是地表分水岭之外地下水沿断裂远程补给。

According to the 1 ： 50 000 hydrogeological investigation of karst area in southwest Hubei Province, it has been found that some underground river＇s catchment areas measured by conventional methods were contradicted with its outlet flow. Taking the Shuigu Cave for an instance, based on the hydrogeological survey, tracer test and other comprehensive technique methods, a conclnsion conld be drawn that there are two main factors which cause the mistake of the under ground river outlet flow is large, however, its catchment are relatirely small, the one is interbasin recharge of surface wa- ter; the other is remote recharge through fault zone in outside surface watershed.