Interpretative filtering

Abstract

Industry already acknowledges the power of dip-steered median filters to clean-up seismic data volume in which coherent events are enhanced and random noise is reduced. By combining two powerful technologies, this paper presents a dip-steered geostatistical filtering solution, called interpretative filtering (IF), which gives remarkable results for removing random and organised noise from seismic volumes. It defines a new generation of spatial filters useful for processing and interpretation. The IF solution is based on a 3D non-stationary factorial kriging technique (M-GS technology) driven by a high-resolution interpretation of the seismic volume coming from a Relative Geological Time model. This new technique enables some non-stationary noise to be dealt with. For example acquisition footprints are well known to be non-stationary noises, with varying orientation, width and intensity as a function of the position in the volume. IF opens the way to refine filtering operations of seismic volumes even in complex structural environments. For this paper, the solution is applied to an open-file 3D marine seismic dataset (HCA2000A 3D) covering the Exmouth sub-basin, North West Shelf, Australia. This survey presents a dense fault system, mostly intersecting the Jurassic and the Cretaceous. Results show a great improvement on reducing the acquisition footprint and random noise without compromising the definition of the subtle geological features.