Domain Transformation in CASI: Building a Volume of Paleo-Depositional Surfaces

William S. Hammon, Geoffrey A. Dorn, Benjamin J. Kadlec, and Jonathan Marbach
TerraSpark Geosciences, L.P., Boulder, CO

For the purpose of stratigraphic interpretation, an ideal seismic volume would be completely free of structural deformation and dip. Each horizontal slice would represent a depositional surface in its entirety. Channels, delta lobes, and crevasse splays would all exist in uninterrupted horizontal slices.

Domain Transformation is an interpretation-guided procedure that transforms a seismic volume to an undeformed state. Seismic traces are resampled and repositioned in order to build a stratal volume. This resampled volume consists entirely of stratal slices, where depositional surfaces are unbroken by geologic deformation.

The Domain Transformation process is an interpretation-constrained set of algorithms that transform a volume to undo the effects of geologic deformation. Algorithms embedded in Domain Transformation accommodate differential sedimentation, differential compaction, removal of fault displacements in 3D, unconformities (including angular), allochthonous salt bodies, canyons, and reef intervals. Noisy or reflection-free intervals are also handled well by this approach.

The process of Domain Transformation makes depositional elements in a seismic volume easier to recognize and interpret. The resultant volume consists entirely of stratal slices - stacked depositional surfaces, free from deformation and dip. Interpretation of depositional elements in the transformed stratal slice volume may be inverted back to their proper position in the time/depth domain. This enables their further use in prospect development, well planning, and fluid flow modeling.

AAPG Search and Discover Article #90078©2008 AAPG Annual Convention, San Antonio, Texas