Abstract：Prestack AVO three-term inversion can provide more information than poststack acoustic impedance inversion,such as P-wave and S-wave impedance,and P-wave and S-wave velocity.So it becomes a powerful tool for reservoir prediction.But in practice,some more sophisticated works need to be done for successful prestack AVO three-term inversion.In this paper,we use prestack AVO three-term inversion based on Fatti formula to predict oil-bearing reservation.A comprehensive strategy and some key steps are revealed,including sensitive attributes analysis,angle-depended wavelet extraction,initial model building,and so on.The inversion results are then combined with petrophysical crossplots obtained from well logs to derive more relevant reservoir properties like porosity,Poisson's ratio,water saturation,and sand percentage,which in turn are calibrated with available logs to validate the confidence in the prediction.Our experience and applications show that the proposed idea and strategy provide good help for successful reservoir prediction with the AVO three-term inversion.
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