High Resolution Walkaway VSP at Kapuni Recorded on Multi-fiber DAS and Geophones

Abstract

Walkaway VSP data acquired over the Kapuni field provided a rich set of very high quality dual well geophone and DAS VSP data. A standard VSP pre-processing workflow was applied, followed by reverse time migration. In the DAS preprocessing we were faced with additional challenges; correct for differences in DAS channel spacing due to variations in optical properties of the various fibers and to compensate for the lack of broadside direct arrivals in the up/down deconvolution at large offsets. The final pre-processed DAS data has a larger vertical aperture than the geophone data resulting in a wider lateral image from a single well. Both the dual well geophone VSP and the single well DAS VSP images provide a good result with high vertical and lateral resolution in the objective area.