Robust Estimation of Large Surface-Consistent Residual Statics

Abstract

Surface-consistent residual static correction is applied to land data on a routine basis. However, if the statics are large, conventional methods often break down due to, among other reasons, the difficulty to construct a good pilot trace. We developed a large static correction method that constructs the pilot trace by a local robust L1-norm inversion at each CDP location. The local inversion calculates the relative time shifts of the traces within a CDP gather by minimizing the trace-to-trace time difference. A pilot trace is obtained by stacking the CDP gather after aligning the reflectors by applying the time shifts to the traces. Finally, a global L1-norm inversion resolves the source and receiver statics from the time shifts of traces of all CDP gathers relative to their pilot traces. The method is demonstrated with synthetic and real data examples.