APPLYING AVO ANALYSIS TO GPR DATA

For reflected-wave phenomena in both seismology and ground-penetrating radar (GPR), the amplitudes of the reflected waves depend on the inci dence angles and the physical properties of the media above and below an interface. Amplitude variation with offset (AVO) analysis employs k nowledge of reflected-wave phenomena to constrain the physical propert ies of two media at an interface. Ostrander (1984) demonstrated that A VO analysis can be used on seismic reflection data in certain instance s to obtain information about the subsurface not revealed by traveltim e-offset relationships (i. e., traditional seismic cross sections). Qu antifiable information about the physical properties of the subsurface may then be extracted. AVO analysis, proven for a decade to work well in reflection seismology, may be useful in near-surface hydrogeologic al situations when applied carefully to GPR data to better constrain t he presence or absence of nonaqueous phase liquid contaminants (NAPLs) in the subsurface.