Patent ID: 9075154
Filing Date: 2015-07-07
Classification: G01V

Abstract:
1. A method for electromagnetic geophysical surveying, comprising: disposing a plurality of electromagnetic receivers in a selected pattern above an area of the Earth's subsurface to be evaluated; repeatedly actuating at least one electromagnetic energy source proximate the electromagnetic receivers; recording signals generated by the receivers indexed in time with respect to each actuation of the at least one electromagnetic energy source; processing the recorded signals to generate an image corresponding to at least one point in the subsurface, the processing including stacking recordings from each receiver for a plurality of actuations of the sources and beam steering a response of the receivers such that the at least one point is equivalent to a focal point of a response of the plurality of receivers; and simulating beam steering of the electromagnetic transmitters by one of selecting a geometric disposition of source current loops and controlling phasing of electric current in the loops.