Methods and systems for performing azimuthal simultaneous elastic inversion

Abstract

An improved method for analyzing seismic data to obtain elastic attributes is disclosed. In one embodiment, a reflectivity series is determined for at least one seismic trace of seismic data obtained for a subterranean formation, where the reflectivity series includes anisotropy properties of a formation. One or more synthetic seismic traces are obtained by convolving the reflectivity series with a source wavelet. The one or more synthetic seismic traces are inverted to obtain elastic parameters estimates. According to one aspect, the data inputs are angle-azimuth stacks. According to another aspect, the data inputs are azimuthal Fourier coefficients u n , v n .

1 . A method for performing azimuthal simultaneous elastic inversion, the method comprising:
 determining a reflectivity series for at least one seismic trace of seismic data obtained for a subterranean formation, wherein the reflectivity series includes anisotropy properties of said formation;   obtaining one or more synthetic seismic traces by convolving the reflectivity series with a source wavelet; and   inverting the one or more synthetic seismic traces to obtain elastic parameters estimates.   
     
     
         2 . The method of  claim 1 , wherein said reflectivity series comprises Fourier coefficients characterizing azimuthal reflectivity at an angle of incidence θ, wherein said reflectivity is determined at least by 
       
         
           
             
               
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         3 . The method of  claim 1 , wherein said inverting step comprises constructing one or more misfit weighting functions that decouple fracture parameter estimation from density, P-wave background velocity estimation, and S-wave background velocity estimation.