A method for controlled source electromagnetic Earth surveying includes
deploying a plurality of electromagnetic sensors in a selected pattern at
the top of an area of the Earth's subsurface to be surveyed. At least one
of a transient electric field and a transient magnetic field is applied
to the Earth in the vicinity of the sensors at a plurality of different
positions. At least one of electric field amplitude and magnetic field
amplitude at each of the sensors is recorded each time the transient
electric field and/or magnetic field is applied. Each recording is
adjusted for acquisition geometry. An image is generated corresponding to
at least one sensor position using at least two stacked, adjusted
recordings.