Independent simultaneous source acquisition and processing

Abstract

Seismic surveys are often constrained by the time needed to activate all the required sources so the source signals do not interfere with each other. Simultaneous source seismic acquisition, also referred to as blended acquisition, is an effective method for reducing the cost and improving the quality of seismic surveys by eliminating the requirement that the sources do not interfere with each other. Independent simultaneous shooting is a unique form of blended acquisition in which sources operate independently of each other and the receiver recording is continuous. This acquisition method is particularly efficient and robust in obtaining high-density source grids for land and marine surveys. Processing the simultaneous source data depends on the randomness of the shot times to create a situation where the signal is coherent, and the interference is random in common-receiver gathers. Although the older and simpler method of separating interfering shots with random noise attenuation works well when the residual interference noise left by the random noise attenuation is acceptable, higher separation quality is possible using a shot separation process based on sparse inversion and compressive sensing methodology. We found that the resulting simultaneous source surveys produced images that were equivalent to or better than conventional seismic surveys, while requiring less acquisition effort, thus reducing costs.