Seafloor Electromagnetic Exploration Methods
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Electrical exploration of the marine environment is just beginning, but interest in the application of electromagnetic approaches is rising rapidly. A brief review of seafloor electromagnetic exploration principles and techniques is given, with an emphasis on the midocean ridge environment. The physical processes governing the electrical conductivity of rocks are discussed. Two types of seafloor electromagnetic exploration systems are then described. The first uses a frequency-domain controlled source to inject energy into the seafloor and has been used for both shallow and deep sounding of the oceanic lithosphere. The second uses a time-domain controlled source and is under development as a tool for rapid, near-bottom surveying.
KeywordsOceanic Crust Midocean Ridge Radial Electric Field Fuca Ridge Vertical Electric Dipole
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