Volume interpretation tools and techniques permit the interpreter to visualize and propagate horizons through entire 3D data sets. Fault interpretation however, is still often accomplished in a line-by-line fashion. When fault interpretation is conducted with visualization tools significant improvements in fault correlation, fault plane intersections, and efficiency can be accomplished.
Early tools applied to 2D or 3D data were limited to fault correlation on maps or time-slices subsequence to the actual fault interpretation. At best fault sticks could be visualized in dimensionless cubes. With the latest generation of visualization tools, three dimensional fault interpretation is possible. The principle advantage is the interpreter can visualize both the dip and the strike of a fault plane. Furthermore, with simultaneous gridding of the fault plane the interpreter can quality control his fault plane interpretation and readily recognize fault tips or terminations and where echelon faults occur. By visualizing along the gridded fault planes the interpreter can also create additional fault sticks to better define along strike changes. Applying opacity and visualizing more than a single 3D traverse can enhance fault recognition. Co-rendering coherency volumes with reflectivity data or combining coherency time slices with reflectivity transverses add an additional aspect to improve interpretation.
Along the Brazilian deepwater margin application of these tools and techniques has resulted in an interpretation of well-defined rollover features bounded by extensional faults. Fault terminations and throw capture by echelon faults will be visualized. A demonstration of the interpretation methodology using GeoprobeTM and Reservoir NavigatorTM will illustrate the effectiveness of this interpretation style and the advantage of simultaneous fault gridding.
We will quickly explore the relationship of underlying basement faults to salt welds and overlying extensional faults to mitigate migration risk. In addition, the effectiveness of combining coherency and reflectivity volumes for fault interpretation will be readily apparent in this complexly faulted data set.