This paper develops the wavefront curvature correction for the plane-wave Zoeppritz coefficients. The authors imply that seismic reflection amplitude versus angle of incidence does not enhance detection of pore-fluid-caused amplitude anomalies (“bright spots”) as proposed in the scientific literature by Backus et al (1982), Ostrander (1982), and Stolt (1981).
We believe certain parts of this discussion are incorrect.
Points of disagreement are as follows.
(1) The model parameters associated with Figure 6 (especially the values for the brine-filled sandstone) are unrealistic and are not taken from Domenico (1977) as the authors have indicated.
(2) The conclusion “… it is clear that the CMP gather by itself fails as a gas indicator” based on Figure 6 is incorrect.
(3) A reflecting spherical wave having a radius of curvature equal to approximately one-half wavelength (kr = 3) requires a shallow reflector unreasonable for petroleum exploration.