高频大地电磁测深在米仓山特长隧道勘察中的应用研究

Application of the High-frequency Magnetotelluric Sounding Method in Survey of Micangshan Extra-long Tunnels

采用高频大地电磁测深法应用于桃巴高速公路的亚洲第二特长隧道——米仓山隧道构造、岩性的勘察,通过与钻探及地质调绘的资料对比,EH4音频大地电磁法可以在宏观上查明深埋隧道地层岩性分界、地质构造(断层、岩溶)及其赋水性,为钻孔布置及隧道设计、施工提供地球物理依据,在深埋隧道勘察中能起到理想的效果.

The high-frequency magnetotelluric sounding method is applied to Asia＇s second extra-long highway tunnel Micangshan Tunnel. By contrast with the data of drilling and geological survey, EH4 audio-frequency magnetotelluric method can identify the lithology, geological structure（faults, karst） and the water content of rock at the macro level, and provide geophysical basis for the tunnel layout and tunnel design and construction. This method is a good survey method for deeply-buried long highway tunnels.