A Survey Design Case History Using Complimentary Ray-Tracing and Wavefield Extrapolation Techniques
P. J. Christian, T. Pringle, L. Zuehlsdorff, A. Drottning, G. Brown and B. Webb
Event name: 2nd EAGE International Conference KazGeo
Session: Seismic Acquisition and Processing, Case Studies I
Publication date: 29 October 2012
Info: Extended abstract, PDF ( 969.94Kb )
Price: € 20
We present a survey design and modelling case history showing how complimentary modelling techniques were used to optimize and de-risk a new seismic acquisition programme. A recent discovery sits close to a salt diapir and although not affected by the salt, the towed streamer seismic exhibits a shadow zone. The aim of the study was to choose new acquisition geometry and demonstrate that acquired data could be successfully processed. In the first part of the study we used ray-tracing to assess sub-surface illumination for a number of acquisition geometries including OBC. In the second part of the study we used wavefield extrapolation modleling to create and process synthetic seismic datasets for the existing conventional (narrow-azimuth) data as well as the new OBC geometry. We show how the use of complimentary modeling techniques (RT and WE) enabled us to de-risk a new survey design. While the ray-tracing allowed us to model the optimum sub-surface illumination and provide a multiple-free synthetic dataset, the wavefield extrapolation modeling provided the opportunity to predict the final image quality before and after multiple attenuation. We suggest that the approach adopted will be applicable to many potential surveys where improved imaging and multiple attenuation is a requirement.