Salt Delineation: Data Driven–Interpreter Guided Extraction of Salt Morphologies from Seismic Data

Gaynor Paton¹, Michael Halpin², and Ryan Martin²
¹ ffA, Aberdeen, AB23 8HZ, United Kingdom
² ffA, Houston, Texas 77024

Gulf of Mexico subsalt plays have produced some significant discoveries over the last 15 years. However, subsalt projects are complex and expensive and accurate identification of the salt, its localization and geometry as well as understanding the halokinesis, are critical for de-risking well placements. In this study we have used new techniques that examine the geological expression of salt in seismic data to accurately delineate salt boundaries. Seismic data contains a wealth of information about the geology but because the information about different aspects of the geology is all aggregated it can be difficult to access the pieces of information that are important in achieving a specific objective. Attribute analysis techniques address this problem by “unscrambling” the data and translating it into geological information allowing the geology to be interpreted more effectively. However, as seismic data provides a non-unique representation of the sub-surface extraction of geological entities from attribute data needs to balance the objectivity provided by data driven techniques with the subjectivity of purely interpreter driven techniques. This non-trivial task has been accomplished in a new adaptive geobody technology that is extremely effective in salt delineation. The principals behind this technique will be illustrated in a case study from the Southern North Sea, although the technique is equally effective in the Gulf of Mexico. The case study demonstrates how the new technique very quickly and efficiently provided high resolution information about the morphology and halokinesis of salt diapers and enabled identification of different episodes of salt movement and visualisation of fingers of salt extending away from the main diapir.

AAPG Search and Discovery Article #90158©2012 GCAGS and GC-SEPM 6nd Annual Convention, Austin, Texas, 21-24 October 2012