Spectral Fusion – A Tool to Combine Low and High Frequency Datasets

“Spectral fusion” is a new multi-trace filter which addresses the purpose of merging two seismic traces or datasets whose frequency spectrums modules have a partial overlap. Pillet et al. (2007) presented a specific application of pre-stack inversion, aimed at using a low-frequency dataset in a first inversion, in order to bridge the 7-16 Hz frequency gap in a second target inversion of a HR seismic. In parallel to this workflow which was carried forward to be used in operation, the geophysical team at Total’s Geosciences Research Center in Aberdeen took a different route and restated the problem directly from the seismic side. The idea was to find a generic way to combine two surveys which mainly differ by their respective bandwidths. When doing so, it is necessary to deal with the overlapping bandwidth appropriately. Spectral fusion directly enables to bridge the low-frequency gap of the high-resolution survey using the conventional, lower bandwidth streamer data. The method also improves the seismic well-tie. Spectral fusion was originally filed for patent in the UK on 9th May 2008 under GB 0808418.8.