Broadband Processing of P-Cable Data in the Barents Sea

The P-Cable system is an efficient method of acquiring high resolution 3D seismic data and this has recently been used extensively in the Hoop area of the Norwegian Barents Sea. Source and receiver depths around 3 m resulted in the data being deficient in low frequencies. This reduced the bandwidth and hence the resolution of the final conventional product. The data recorded were very densely sampled in the inline, crossline and time dimensions, but the native CMP fold and the range of offsets were poor. This resulted in a low signal-to-noise ratio in the final stack.

These issues were successfully addressed in processing. The ghost notches were handled by a deghosting technique extending the low frequencies from 50 Hz down to below 8 Hz. On the 2D data a shot stack, rather than a CMP stack raised the fold to 128 and this was used to deliver a high signal-to-noise section. On the 3D data a post-stack frequency dependent radial mix and FXY deconvolution achieved similar results.

Having produced a high bandwidth, high resolution dataset the geologists were able to produce a much more detailed interpretation and even use the data for detecting potential geohazards.