Converted-wave Processing of an Ocean Bottom Cable Dataset from the Arabian Gulf

The processing of PS waves from a 4-component converted-wave dataset can provide complementary information to that obtained from traditional P-wave imaging. However, processing the PS component requires additional care to ensure the full potential of the data is realised. This paper discusses the specific processing required for a shallow-water converted-wave dataset acquired with an Ocean Bottom Cable (OBC) system in the Arabian Gulf.

Vector fidelity, receiver-side shear statics, and compensation for shear-wave splitting in the overburden are key topics that had to be addressed in the pre-processing. After further corrections for deeper shear-wave splitting, the PS data were regularised with differing schemes: for analysis of gamma-effective and pre-stack time migration velocity analysis; and for the migration of the data itself.

To maintain data integrity it was important to preserve the signal on both the radial and transverse components through all the processing steps up to and including migration. This ensured a final shear-wave splitting analysis could be made post migration at the target level to minimise any residual shear-wave splitting effects prior to final interpretation and in preparation for a joint PP-PS inversion.