Design of the Blackfoot 3C-3D seismic program was reviewed by evaluating presurvey and post-survey fold plots, and comparing predicted fold with the stacking fold extracted from the processed data volume. The survey was designed initially using asymptotic binning and Flexi-bin® acquisition geometry with a sub-bin interval of 10 m for the P-S data. The survey consisted of 1395 source points and 903 receivers, recorded in 2 fixed patches with up to 700 receivers per patch. Processed stacking fold distribution matched closely the pre-survey depth-variant fold distribution computed using an offset range of up to 2300 m for the P-S data. Maximum fold for 30 m x 30 m bins at the Glauconitic target level reached 100 in the centre of the Glauconitic patch, and greater for later events. Fold distribution was good, with relatively minor bin-to-bin and sample-to-sample variations within the volume from the Glauconitic patch. Some fold striping parallel to the receiver lines was noticeable over the Beaverhill Lake patch where a receiver line interval of 495 m was used.
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