3-D f-k filtering

Robert R. Stewart, David G. Schieck

Seismic sections or slices resulting from the processing of 3-D data can often be enhanced by the application of various filters. This study investigates the design and use of 3-D f-k filters operating on the post-stack data volume. In particular the results of a one-pass true 3-D filter are compared with those realized from two perpendicular passes of a 2-D filter. In principle, given a specific velocity (dip) reject range, the basic two-pass 2-D filter and a one-pass 3-D filter have a different response. In fact, filtered synthetic data show that the two-pass filters do not provide axially-symmetric results; greater dips are passed at 45 degrees to the filtering directions. The one-pass 3-D filter does provide axially symmetric results. This study also compares a mean and median implementation of the 3-D f-k filter. The application of the mean filter results in a more smoothed image than use of the median-based filter. In cases where 3-D edges (faults) should be preserved or where the data are particularly noisy, the median design may be more desirable.