Combined application of reflection seismic and EM data to stratigraphic mapping

Abstract

Electromagnetic (EM) methods, principally magnetotellurics (MT), have been widely used in petroleum exploration when there has been difficulty with reflection seismics. Examples are basalt-covered areas (Stanley et al., 1985), and in overthrust belts (Berkman et al., 1983). This has been successful because EM methods respond to different physical properties than do seismic methods. Seismic scatterers do not generally affect EM signals, so there is a logical argument for combining methods if a suitable problem arises. However EM methods do not have the intrinsic spatial resolving power of reflection seismology.