3D Inversion Modeling of Natural and Controlled Source EM in Complex Terrain

Summary Controlled source, grounded electrode EM surveys have a long and successful history in mineral exploration geophysics, where the most commonly deployed configuration is CSAMT, which uses single, fixed, kilometre-long transmitter dipoles (e.g. Zonge and Hughes, 1991). More recently, however, hybrid survey configurations are gaining in popularity, including surveys using multiple transmitter and receiver dipole locations and orientations (e.g. Grayver et al., 2014). While it may be strictly accurate to refer to these generically as controlled source EM surveys (CSEM), here we retain the use of CSAMT given its historical significance and continuing, broad industry acceptance.