Being “interactive” is not only important for traditional seismic interpretation, which maps subsurface structural and stratigraphic features; it should also be an essential feature in the seismic attribute analysis for reservoir characterization and prediction. In this paper we present interactive workflows that integrate major steps in seismic attribute analysis, namely attribute calculation, visualization, calibration, classification, and prediction. Interactive analysis workflows are demonstrated as more effective and powerful than traditional linear workflows.
We introduce the “strata-grid” as the major object for analyzing attributes in the interactive attribute workflow. A strata-grid defines a target stratigraphic volume, based on stratigraphic relationships, that is proportional, top-conformable, or bottom-conformable. Seismic attribute features are better delineated on stratigraphic slices within a strata-grid, rather than through traditional time slices or simple horizon slices. The strata-grid makes the interaction with the data possible, not only for visualizing the data but also for quantitatively analyzing attributes for large 3D seismic surveys – without handling the whole data volume.
Interactive analysis of attributes not only improves the interpreter’s efficiency, it allows users to identify reservoir features that would otherwise be missed in a non-interactive approach. For example, the real-time link between attribute generation and visualization makes it possible to quickly fine-tune calculation parameters to generate quality attributes and to find better attributes to characterize reservoir properties.
The power and usability of facies classification and prediction methods are greatly enhanced in an interactive workflow, since results based on different assumptions can be verified and calibrated with well data quickly. In addition to the real-time link between analysis methods and visualization; a co-rendering of multiple attributes in 2D or 3D can generate seismic facies maps or facies volumes interactively, which complements the algorithm-based classification methods. Through real-world examples, we illustrate that the full potential of seismic attributes are better realized through interactive workflows.
Renjun Wen, Geomodeling Technology Corp.
Published in Attributes: New Views on Seismic Imaging — Their Use in Exploration and Production: 31st Annual GCSSEPM Research Conference Proceedings, Vol. 31, 2011