Preliminary Research On The Geothermal Abnormalism And Its Impact On The Tunnel Construction In The District Of Gaoligong Mountain

This paper chooses the geothermal abnormalism in Gaoligong mountain as research objiect. Through analyzing the regional geothermal and geologic background,do some researches on the spring distribution characteristics and its control factors, find the spring appear on the zonal distribution along the east-west, which show the distribution of geothermal abnormalism has intimate connection with the active fractures. Across the study of hydrochemical and isotope geochemical characteristics, HCO₃-Na is the main spring hydrochemical type in this area, and the content of the characteristic component SiO₂ and F in the spring is clearly higher than that in the suface-water. The spring recharge really comes from the atmospheric precipitation, which belongs the deep circulation hydrothermal water caused by the percolation. Through the calculation of geochemical thermometers, the geothermal reservoir temperature is in the range of 43.7-186.6℃. Moreover, on the base of the geothermal formation condition analysis, this paper preliminarily discusses the geothermal origin and formation model,and analyzes the impact on the tunnel construction caused by the geothermal action,which provide definite theoretical basis for the selection of tunnel programs and have important significance for further proper program decided, construction safety guaranteed and construction progress assured etc.