Discussion and conclusion

There are two major advantages of using anisotropic processing over isotropic processing on seismic data. One advantage concerns the quality of the final image: anisotropic processing in areas that contain critical amounts of shale in the subsurface yields better images than isotropic processing. The improvements include better focusing and imaging (positioning) of faults, as well as better focusing of stratigraphic imaging as evidenced by the enhanced continuity of horizontal reflections. The second advantage is an interpretation one: the $\eta$ curves obtained through anisotropic processing provide us with important lithological estimation tool, used here to distinguish between sand-dominated layers and shale-dominated ones.

The imaging benefits of anisotropic processing have been demonstrated previously, but the potential of using the geologic parameter $\eta$ for lithology estimation shows great potential in current exploration activity. Correlation with gamma ray curves demonstrates the ability to estimate sand and shale dominated intervals in the subsurface. One potential application is in deep water exploration areas where reservoir presence can be difficult to determine. With deep water well costs increasing, additional information that can reduce drilling risk is extremely important. This technique does not require expensive or unusual acquisition procedures--the only requirement is a new look at existing data using refined processing techniques that incorporate real geologic parameters.