Interpretation of 3-D seismic data
After 3-D migration, a 3-D data volume is suitable for derivation of the 3-D subsurface geological model. Because of the completeness of data within that volume, the interpreter has more information than he would from the analysis of a 2-D seismic data set. Although more information leads to less uncertainty in deriving the geological model, interpretation of abundant data can be exhausting. The use of an interactive interpretation workstation is a common way to deal with large 3-D data volumes. Moreover, an interactive environment is versatile in viewing the 3-D data volume. For example, we can examine vertical sections in inline, crossline, or any arbitrary direction, as well as horizontal sections, namely, time slices. An interactive environment also can provide the capability to improve interpretation. For example, horizon flattening, correlation of marker horizons across faults, and some image processing tools to enhance certain features within the data volume can be implemented.
First-generation 3-D interpretation systems were based on the principle of line-by-line interpretation. Contemporary 3-D interpretation systems are based on volume visualization and manipulation of amplitudes within the image volume to enhance structural and stratigraphic features of interest. With the availability of powerful hardware and software visualization tools, interpretation no longer is picking a set of horizons and discarding the rest of the image volume. Instead, interpretation involves using both traveltime and amplitude information contained in the entire image volume. Specifically, structural interpretation is primarily based on picking traveltimes that are coincident with geological layer boundaries, and stratigraphic interpretation is based on manipulation of seismic amplitudes to enhance subtle features associated with depositional environment and sedimentology.
- Time slices
- 3-D visualization
- Removal of opacity
- Seed detection
- Structural interpretation
- Stratigraphic interpretation