A reconnaissance audio-magnetotelluric survey at Kilbourne Hole, New Mexico
— D. B. Hoover and C. L. Tippens

The audio-magnetotelluric, AMT, method is an electromagnetic exploration technique which uses energy derived from world wide lightning storms to measure variations in earth resistivities as a function of depth and position. Because it is an electromagnetic technique it is particularly applicable to locating conductive rather than resistive bodies. A comprehensive review of the method is given by Strangway and others (1973) and details of the U.S.G.S. system is given by Hoover and others (1974).