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A Survey Design Case History Using Complimentary Raytracing and Wavefield Extrapolation Techniques
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, 74th EAGE Conference and Exhibition incorporating EUROPEC 2012, Jun 2012, cp-293-00854
- ISBN: 978-90-73834-27-9
Abstract
We present a survey design and modelling case history showing how complimentary modelling techniques were used to optimize and de-risk a new marine seismic acquisition programme. A recent discovery sits close to a salt diaper and although not affected by the salt, the towed-streamer seismic exhibits a shadow zone. The aim of the study was to choose a new acquisition geometry and to demonstrate that acquired data could be successfully processed. In the first part of the study we used ray-tracing to assess subsurface illumination for a number of acquisition geometries including ocean-bottom cable (OBC). In the second part we used wavefield extrapolation modelling 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 modelling techniques (raytracing and wavefield extrapolation) enabled a de-risking of the survey design. While the raytracing allowed us to model the optimum subsurface illumination and provide a multiple-free synthetic dataset, the wavefield extrapolation modelling 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 required