f Tests of a Two-Step Correction Procedure for Long-Offset Data

The use in recent years of offset-to-reflector depth ratios of two or three rather than the unity common earlier has resulted in traveltime-offset curves that are not hyperbolic. For long offsets or where anisotropy is important, a need to include a quartic term in the squared traveltime-squared offset function has been established. Long offsets are common today for AVO analysis in areas such as the Gulf of Mexico.