Iterative Deblending of off-the-Grid Simultaneous Source Data

Abstract

Simultaneous source acquisition can enhance the seismic data quality or improve the field acquisition efficiency. However, one of the disadvantages is that the simultaneous source data are often obtained on a non-uniform sampled grid in realistic acquisition. Except for the blending noise introduced by the temporal overlap, the non-uniform samplings usually causes serious artifacts which also greatly reduces the data quality and imaging resolution, such that data regularization must be implemented during the deblending. At present, most deblending algorithms are suitable for the uniformly sampled data. Thus, we propose the nonequispaced fast discrete curvelet transform-based deblending approach to deal with the nonuniformly sampled simultaneous source data. In order to enhance the deblending efficiency, we introduce the iterative shrinkage thresholding algorithm to solve the undetermined problem via a soft thresholding operator. Once the coefficients in the curvelet domain are acquired, uniformly sampled deblended data can be obtained via inverse curvelet transform. During the iterations, the threshold is decreased from a large value to a small value according to the new exponential function. Compared with the existing deblending methods that are applied on uniform grids, the key contribution is that the proposed method can directly work on the non-uniformly sampled simultaneous source data. The numerical examples are used to demonstrate the successful performance of the proposed method in attenuating blending noise and correcting the distorted events.