Frequency-dependent Azimuthal Effects on P-Wave Reflections from a Thin Layer
Z. Jin, M. Chapman, X. Wu and G. Papageorgiou
Event name: 79th EAGE Conference and Exhibition 2017
Session: Seismic Anisotropy - Understanding the Fracture Influence
Publication date: 12 June 2017
Info: Extended abstract, PDF ( 1.25Mb )
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This paper examines the impact of anisotropic dispersion on P-wave reflections. We show a modest effect on the amplitude and large effect on the phase, the latter of which could be mistaken for azimuthal velocity variations. We present a Bayesian inversion based on a forward modelling technique aimed at recovering layer thickness, fracture density, and fracture length in a thin-layer example. Our results show that the large-scale fractures can be clearly distinguished from microcracks despite the presence of interfering reflections, provided we have a sufficiently accurate background velocity model.