Case History: 3-D Shear-wave Processing And Interpretation In Radial-transverse (SV-SH) Coordinates

Summary A 9-C 3-D seismic reflection data set from Clark County, Kansas is processed to produce SH and SV data volumes. Data processing is quite straightforward; rotation of the data from field coordinates to radial-transverse coordinates, static corrections (elevation, shot, and receiver) derived from the SH data, NMO correction with a single velocity function, inside-trace mute, and stack. Super gathers monitor the convergence of the shear-wave statics, which are found to be relatively small (+/- 40 ms), and simple to estimate from the dominantly 12 Hz SH data. Single velocity function NMO (velocities derived from SH) show the SV data to be slightly overcorrected, suggesting the presence of vertical transverse isotropy. An inside-trace mute eliminates the surface-wave noise cone. Dominant reflections in the stacked data are from the top and base of the Morrow clastic interval. Reflection signal quality is superior on the SH data.