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In Yunnan Province, highway construction, increasing long deep tunnel, the traditional engineering geological investigation only by means of observation and analysis of the deep surface geology, supplemented by a small amount of drilling verified information obtained this way of working hard to meet the deep long tunnels design and construction needs. The geophysical methods capable of continuous observation for extensive ground information in a short time, low-cost, high-quality finish tunnel geological reconnaissance missions. Yunnan Highway Planning and Design Institute 20 years accumulated a lot of tunnels survey data, but the system has done research, this paper hope that through these tunnels survey data for research, geological prospecting for highway tunnel provides a fast and effective geophysical methods, thereby improving Tunnel Geological Survey quality, shorten the exploration cycle, saving geological survey fees. Taking into account the probing depth and geophysical methods in the tunnel investigation of the effectiveness of the application, the paper chose sounding method, transient electromagnetic (TEM), controlled source audio magnetotelluric method (CSAMT), high-frequency magnetotelluric method ( EH4), seismic refraction and seismic reflection method geophysical methods buried long tunnel Geological Survey of applied research. Firstly, from a theoretical point of view of these geophysical methods can be applied to buried long tunnel lithology, geological structure, groundwater and rock categories investigation, through the tunnel lithology, geological structure, groundwater and rock types of common physical properties (resistivity and vertical velocity), anomaly summary and geophysical methods are mainly influencing factors analysis, that the majority of tunnel geological problems with the application of geophysical methods investigation of the physical basis, although geophysical observations by many factors interfere, but most interference can be overcome, geophysical methods can obtain a valid exception. Then paper selected six typical examples of tunnel investigation of electrical sounding method, TEM, CSAMT, EH4, seismic refraction and seismic reflection wave method in the tunnel lithology, geological structure, groundwater and rock categories INVESTIGATION effect analysis, the analysis showed sounding method, TEM, CSAMT, EH4, seismic refraction and seismic reflection method can solve most of the tunnel lithology, geological structure, groundwater and rock classification survey questions. Through the application of feasibility studies and case studies, combined with my research over 20 tunnels survey data acquired knowledge, summed up the long tunnel buried lithology, geological structure, groundwater and rock categories effective Geophysical survey methods and combination of methods, and an effective method of field work, data processing and interpretation methods.
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