Improved visualization of structural deformation on the Kraka structure (Danish Central Graben) with color-processed seismic data

We use colour processing and ant-tracking techniques to resolve subtle features on 3D seismic data of the strata overlying a salt pillow in the Danish Central Graben. This reveals a series of subtle pipes and planar zones of high intensity signal, which are resolved as inclined lineations on vertical sections and form a polygonal pattern when projected onto stratigraphic horizons. Although these show some similarities in location and orientation with resistive fractures seen on borehole images and large cemented fractures seen on core, there is not a 1:1 correspondence, and the lineations are broader and more diffuse than the fractures. They are more likely to represent zones of low porosity surrounding fractures and small faults, resulting from compaction and/or cementation caused by escape of overpressured fluids through the fractures.