The towed EM system used for measuring subseafloor resistivity in coastal settings. The system is a magnetic dipole-dipole array (~40m long). It consists of a transmitter (large cylinder on the right) which generates magnetic fields at a number of frequencies. These fields are recorder by 3 receivers (small tubes on the left). The whole system is dragged in a line along the seafloor at speeds of 1-2knots. The furthest receiver (40m) measures the deepest structure, to about 20m subseafloor. More details and examples of the systems usage are given in Evans, Geophysics, 72, 105-116, 2007.
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