New features in SYNGRAM
Gary F. Margrave
The CREWES AVO synthetic seismogram facility, SYNGRAM, has been upgraded to include several new features. These are (1) An interactive AVO analysis tool, (2) The option to create angle gathers as well as the traditional offset gathers, and (3) a wavelet display axes. The AVO analysis panel allows the interactive selection of an analysis level and then compares the AVO in the gather with that from a simple Zoeppritz calculation. These tend to agree on strong reflectors but not on subtle ones. The angle gathers are created by tracing rays from each reflector to the source and receiver at constant incidence angle regardless of the ultimate offset. Angle gathers are contoured with offset values while offset gathers are contoured with angle values. Finally the wavelet display panel provides a visual reminder of the selected wavelet and is plotted at the same scale as the seismogram and logs. This provides a direct assessment of resolution in either time or depth.