Multiple attenuation: A 3-D field data example

Chapter introduces a Gulf of Mexico 3-D dataset donated by the Compagnie Générale de Géophysique (CGG), where multiples are attenuated with the pattern-based technique of Chapter . With 3-D data, obtaining an accurate model of the multiples becomes the biggest challenge because the acquisition geometry is not regular. Therefore, the method of Verschuur et al. (1992) cannot be directly applied on the data without interpolation. Worst, the data need to be interpolated and extrapolated on a regular and fine mesh in both inline and crossline directions. With 3-D data, the cost of such processes can be prohibitive and alternatives are needed. In this Chapter, I propose doing the interpolation in the inline direction only and model the multiples in a 2-D sense, one streamer at a time. The shots are interpolated with a radon-based technique on common-mid point (CMP) gathers. I show that the resulting noise model from the 2-D prediction, although not perfect, still encapsulates the main features of the true multiples present in the data. Because the pattern-based method is robust to modeling uncertainties, the primaries are well recovered regardless of the approximations made during the model building.