Measuring velocity from zero-offset data by image focusing analysis

Measuring velocity from zero-offset data by image focusing analysis

Biondo Biondi

Abstract:

Migration velocity can be estimated from zero-offset data by analyzing focusing and defocusing of residual-migrated images. The accuracy of these velocity estimates is limited by the inherent ambiguity between velocity and reflector curvature. However, velocity resolution improves when reflectors with different curvatures are present, as demonstrated by simple synthetic examples. The application of the proposed method to zero-offset field data recorded in the New York harbor yields a velocity function that is consistent with available geologic information and clearly improves the focusing of the reflectors.