Patent ID: 7761237
Filing Date: 2010-07-20
Classification: G01V

Abstract:
1. A method for compensating for dip-induced errors in Amplitude-Variation-with-Offset (AVO) attributes or in Azimuthal AVO (AzAVO) attributes derived from a 3-D seismic data volume obtained from a seismic survey of an isotropic dipping reservoir lying beneath isotropic overburden, comprising: (a) accounting for azimuth dependence of energy divergence in seismic wave reflected from the dipping reservoir; and (b) accounting for azimuth dependence of reflection angle reflected from the dipping reservoir in the 3-D seismic data volume; wherein accounting for azimuth dependence of energy divergence and reflection angle comprises (c) applying AzAVO inversion to the 3-D seismic data volume to generate four attribute data volumes A, B, B′ and ψ (d) calculating dip angles φ at the reservoir's upper surface and multiplying cos φ by A to obtain dip-compensated AVO intercept attribute A (e) calculating dip-compensated AVO slope attribute B (f) calculating the actual dipping reservoir's dip azimuth ψ