Method of processing seismic data

A method for determining the anisotropic properties of an unknown earth formation by means of generating seismic signals for propagation through said unknown formation, comprising the steps of:

• obtaining seismic data samples related to a detected range of seismic signals generated by a propagation of said generated signals through said unknown formation, said detected signals being affected by the anisotropic properties of said unknown formation,
• selecting, for said unknown formation, a group of postulated anisotropic properties which would cause known perturbations in seismic signals,
• comparing the seismic data samples related to the detected range of seismic signals from said unknown earth formation with data points related to estimated ranges that could have been produced by seismic signals propagating through earth formations made up with differing weighting of components of the postulated anisotropic properties, and
• identifying the estimated range that best matches the detected range through said comparison of the seismic data samples, and attributing the related weighted components of the postulated anisotropic properties to said unknown earth formation.

A method for determining the anisotropic properties of an unknown earth formation by means of generating seismic signals for propagation through said unknown formation, comprising the steps of:

• (a) obtaining seismic data samples related to a detected range of seismic signals generated by the propagation of said generated signals through said unknown formation, said detected signals being affected by the anisotropic properties of said unknown formation;
• (b) selecting, for said unknown formation, a group of postulated anisotropic properties which would cause known perturbations in seismic signals;
• (c) comparing the seismic data samples related to the detected range of seismic signals from said unknown earth formation with data points related to estimated ranges that could have been produced by seismic signals propagating through earth formations made up with differing weighting of components of the postulated anisotropic properties;
• (d) identifying the estimated range that best matches the detected range through said comparison of the seismic data samples, and attributing the related weighted components of the postulated anisotropic properties to said unknown earth formation;
• (e) corresponding the seismic data samples with scattering angles and azimuth at each migration dip at each point of the medium;
• (f) applying an inverse operator to the seismic data samples corresponded according to step (e), so as to produce intermediate anisotropic elastic parameter combinations for each migration dip at each point of the medium, the inverse operator comprising an inverse of a scattering function for variations in elastic parameters form a reference medium against scattering angle, azimuth and migration dip;
• and
• (g) migrating the intermediate anisotropic elastic parameter combinations to their proper locations.