Estimation of primaries by sparse inversion in shallow water: Practical challenges and strategies

Estimation of primaries by sparse inversion (EPSI) is an iterative method that effectively separates primaries and surface-related multiples, especially in shallow water. Multiple attenuation in shallow water is challenging, mainly because of acquisition limitations. We propose a strategy for EPSI with the following objectives: (1) creates an alternating picking method for the first iteration of EPSI that correctly separates primaries and multiples and also expedites the convergence in some cases and (2) picks only strong shallow reflectors to alleviate the cost while attacking most of multiples generated by those reflectors . We applied our method to two synthetic data sets. Then, we tested the EPSI method on a complex field data set and demonstrated that it can effectively attenuate multiples.