圆梁山隧道毛坝向斜段岩溶水同位素组分特征

摘要

以圆梁山隧道在毛坝向斜段所穿越的重要层位P1灰岩岩溶水为重点，兼顾整个向斜构造地下水的分布情况，从岩溶水的氢氧同位素组分特征的角度探讨该区地下水的形成、循环交替等信息，为进一步论证隧道施工中可能出现的岩溶突水地质灾害提供依据。%This paper discusses the karst water of P1 limestone and the other types groundwater of the Maoba syncline which the Yuanliangshan tunnel goes through. The information of the formation, circulation and alternation is derived from the composition of H-O isotope in the karst groundwater. The correlatability of the stable H-O isotope fits with the precipitation equation of the southwest region of China. The content of tritium reveals that there are three types about the age of karst water. It is important that the high value of tritium of P1 karst water in the deep drilling-hole hints the existence of rapid circulating and alternating groundwater flow. Furthermore, it is the evidence that demonstrates the possibility of geological hazards about the inburst of karst water into the tunnel.