De-signature of apparition blended seismic data

SUMMARY

State-of-the-art source de-signature technology uses near-field hydrophone recordings to achieve the ensemble of de-bubble, source de-ghosting and zero-phasing with one directional operator.

This paper outlines average and shot-by-shot source de-signature strategies for apparition blended seismic data and their application to a triple-source apparition field data acquired in the Barents Sea We have observed that the periodically encoded firing of multiple source arrays results in blended near-field hydrophone recordings. The relatively large crossline distance between marine sources compared to the subarrays might imply that the contributions from neighbouring source arrays can be neglected because of geometrical energy spreading.

We have found that ignoring source arrays interference results in suboptimal directional de-signature operators. To address this interference, it is necessary to invert for the full set of notional sources for all the source arrays. The estimated far-field signatures at each shot location are then deblended prior to any average or shot-by-shot signature calculation. Furthermore, deblending the far-field directional signatures requires correct handling of the bubble shot-by-shot variations which are not bandlimited to the signal apparition non-aliased regions.