Online Journal for E&P Geoscientists

Paton, Gaynor ¹; Elghorori, Ahmed ^*2; McArdle, Nick ¹
(1) ffA, Aberdeen, United Kingdom. (2) ffA, London, United Kingdom.

The accurate extraction of 3D geobodies that represent geological features is an important aspect of seismic interpretation and the subsequent building of geological models. Currently this can be achieved using manual interpretation techniques, or automated techniques such as volumetric threshold based extraction, or autotracking from a seed-point with threshold limit or range. Both methods have their flaws: manual interpretation of complex geological objects is subjective and time consuming, whilst automated methods rely on a consistent seismic expression within the object to be extracted. We present a new data driven but interpreter guided technique which enables the rapid extraction of geological objects even if they are expressed with a variable seismic character. Fundamental to the technique is the ability for the interpreter to override or influence the growth of the geobody so that in areas of poor data quality a geobody can still be created.

This technique allows geobodies to be grown on single or multi-attribute data more efficiently than existing geobody delineation methods whilst still being extremely simple to apply. The technique is based on a sophisticated analysis of local data statistics that adapts to changes in expression. This data driven technology is combined with intuitive manual manipulation tools that enables interactive 3D editing of geobodies in areas where data driven techniques alone are not sufficient to resolve the geological target. Confidence values computed at every point on the geobody surface are displayed to provide direct visual feedback to the interpreter on how well the geobody is fitting to the data, which in turn helps the interpreter manipulate the geobody more accurately.

This unique technique has enabled systematic extraction of geobodies in areas where all other commercially available techniques have failed. This includes braided channel systems and interconnected karst systems. In this paper we will present a selection of results from different geological settings which illustrate the interpretive advantage of this technique and also demonstrate how it is possible to extract geological features at seismic resolution for inclusion within a geological model.