CSEM Interferometry Using a Synthetic Aperture Source

Abstract

With interferometry by multidimensional deconvolution for Controlled Source Electromagnetics, the medium above the receivers is replaced with a homogeneous halfspace and the source is redatumed to the receiver level. The resulting retrieved reflection response is completely free of any airwave effect. Since the source is redatumed, the original source position becomes irrelevant, which is a useful property for time-lapse surveys. So far, interferometry by multidimensional deconvolution required a densely spaced receiver array. We show that this restrictive sampling requirement can be overcome by combining a lot of source positions to one very long source. By creating such a synthetic aperture source, we were able to apply interferometry for a receiver spacing as large as 1280 m.