Magnetic on-time transient electromagnetic method (MoTEM) for imaging magnetic susceptibility

SUMMARY We present the magnetic on-time transient electromagnetic (MoTEM) method for obtaining information about subsurface susceptibility from (TEM) measurements. The uses primary field produced by a TEM system as inducing and extracts measured late response responses susceptibility. assumes that transmitter waveform is long enough to allow dissipation of eddy currents until electric conductivity effect becomes negligible towards end transmission or its time derivative dominantly Using numerical simulations, we study anomaly different times demonstrate signal dominated (MoTEM signal) at both moving fixed-loop sources. observational evidence presence MoTEM showing they can be identified in data ground survey over ultramafic units Raglan nickel belt. Our lays foundation method, demonstrates it realized with existing acquisition systems, provides guidance new development. could enable mapping imaging airborne EM and, therefore, has potential double content such