Geothermal characteristics of the Xianshuihe fault zone and their engineering influence on tunnel construction

The Zheduo Mountain tunnel crosses the Xianshuihe fault zone in Kangding city. The Xianshuihe fault zone is composed of many large-scale faults and features a complex geological structure and strong geothermal activity. Based on geothermal drilling data, hydrogeological tests and the geothermal geological back-ground of the study area obtained via hydrogeological surveys and hydrogeo-chemical methods in the process of tunnel surveying, this paper explores the exposure characteristics and distribution of geothermal water in the study area, analyses its hydrogeochemical and isotopic characteristics, and thoroughly studies the hydrogeological structure of the geothermal water to explore the genetic mechanism responsible for the formation of the geothermal water. The influence of the geothermal water and high ground temperatures on tunnel construction is further predicted, and practical and effective engineering treatment suggestions are proposed.