Summary
Recent applications of broadband electromagnetic methods used in exploration geology are covered in this chapter. Historically, electromagnetic detection systems used in mineral exploration efforts were designed to utilise a single frequency or a limited number of discrete frequencies. Application of electromagnetic detection methods in geologically complex environments has created a need for a more complete method of discerning the total geological environment. The objective is to be able to map the total geoelectric section, including resistive as well as conductive units. ‘Broadband’ electromagnetic methods have been developed to meet these needs. Electromagnetic detection systems capable of spanning up to five decades of spectral range are in current use. Recent developments in hardware technology and also in in-field data collection, processing, and sophisticated interpretational analysis are discussed in the chapter. These recent advances have contributed to our ability to resolve details of the three-dimensional distribution of resistivity in the subsurface. Results of both frequency-domain and time-domain surveys are presented.
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Motter, J.W. (1983). Broadband Electromagnetic Methods. In: Fitch, A.A. (eds) Developments in Geophysical Exploration Methods—4. Springer, Dordrecht. https://doi.org/10.1007/978-94-009-6625-3_4
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