Fresnel zone binning analysis and quality of seismic data processing F


 Hejie Wang, Usman Raja, Jingdong Liu and Ottar Sandvin evaluate the Fresnel Zone Binning infill criteria used in a 3D survey acquired for Statoil at Nordkapp in the Barentsea.


or a typical 3D seismic survey, infill shooting may account for as much as 25 per cent or more of the total cost of prime line seismic acquisition. Te Fresnel Zone Binning (FZB) infill criterion is an approach designed to minimise infill costs further based on FZB calculated coverage in combination with steerable streamers. Two decimated datasets were generated


in addition to the full dataset, to simulate the more severe lack of coverage in the acquisition. Te three data scenarios were all processed independently, including data regularisation, and finally 3D time migrated. Te processing has demonstrated that


the FZB infill criteria have proven sufficient. Even for the decimated data set with a drop in coverage of -3dB to -4dB, high quality output from the 3D pre-stack time migration was obtained. Most marine 3D seismic surveys are


acquired with infill to ensure adequate subsurface seismic reflection coverage in areas where the surveys may have been


affected by adverse currents, sub-optimal streamer feather angle matching or source/ streamer separations. By understanding the importance and the size of the Fresnel Zone, requirements for coverage as a function of offset, angle of incidence, frequency content and depth can be evaluated accurately. Tese criteria can be used to set steering


tolerances for streamers during acquisition, to further minimize the amount of infill required in a marine streamer survey. Tis approach is called Fresnel Zone Binning (FZB) and has been described by Dave Monk, see Monk 2010 SEG, Denver 2011, Annual Meeting and see also Fig. 1. In the figure FZB dB fold is measured in decibels (dB) down from the nominal fold contributions; with colour scale included.


Nordkapp data scenarios A 3D seismic survey was acquired for Statoil at Nordkapp in the Barent Sea in 2010. Additional decimation of the acquired data was done by removing some of the data from


IHSS 12


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