Optimal filtering high-resolution seismic reflection data using a weighted-mode empirical mode decomposition operator

Gas-hydrate related processes in deep-water marine settings exist on spatial scales that challenge conventional seismic reflection profiling to successfully image them. The conventional approach to acoustic identification of buried hydrates is to use advanced, cost-prohibitive survey techniques and highly customized software to define subsurface structure wherein compositional changes may be modeled and/or interpreted. This study adopts a different approach derived from recent theoretical advancements in signal processing. The method consists in optimal filtering high resolution, single-channel seismic reflection data using the Empirical Mode Decomposition (EMD). The time series is decomposed in sub-components and the noisy portions are suppressed adopting the technique that we referred as Weighted Mode(s) EMD. The optimal filtering greatly improves the resolution and fidelity of the seismic data set.High Resolution single channel seismic profiles, acquired over a carbonate\hydrates site in the northern Gulf of Mexico, manipulated in such way, show a complex, shallow subsurface, and suggest potential evidence for buried gas hydrates.

►EMD is a signal processing technique useful in study non-stationary physical processes. ►In this study We expanded EMD tool introducing the weighted mode EMD. ►High resolution seismic data are optimal filtering adopting the weighted mode EMD. ►Results are used to image complex geology in Gulf of Mexico continental shelf. ►Seismic anomalies might suggest presence of gas hydrates buried sediments.