Green function retrieval versus Interferometric imaging Kees Wapenaar Deyan Draganov Delft University of Technology 2005 Joint Assembly May 25, 2005 New Orleans
Green’s function retrieval Interferometric imaging Comparison Contents
(passive) data
Green’s function retrieval Interferometric imaging Comparison Contents
Phys. Rev. Lett., 2004, 93 (25),
1500 m/s 2000 m/s Retrieval of reflection response: acoustic approximation
(variable ) (fixed, variable )
1500 m/s 2000 m/s Uncorrelated noise sources
(fixed, variable ) (variable )
Green’s function retrieval Interferometric imaging Comparison Contents
(passive) data
Forward extrapolation of ‘source’ Inverse extrapolation of receiver Cross-correlation Integrate along receivers 0 t
Forward extrapolation of ‘source’ Inverse extrapolation of receiver Cross-correlation Integrate along receivers Repeat for all subsurface points Ghost
Schuster, EAGE 2001, GJI 2004 Artman et al., EAGE 2004 Draganov et al., SEG 2004 Ghost
Green’s function retrieval Interferometric imaging Comparison Contents
Green’s function retrieval Integration along sources 1500 m/s 2000 m/s Retrieval of reflection response: acoustic approximation
Green’s function retrieval Integration along sources Interferometric imaging
Green’s function retrieval Integration along sources Interferometric imaging Integration along receivers Ghost
Green’s function retrieval Integration along sources Interferometric imaging Integration along receivers
Passive Seismic Imaging in Complex Media 33 minutes of white noise recording with 225 subsurface sources Numerical comparison with varying number of underground sources Directly modelled reflection response Reconstructed reflection response Reconstructed depth image
Passive Seismic Imaging in Complex Media Numerical comparison with varying number of underground sources 6 minutes of white noise recording with 113 subsurface sources Directly modelled reflection response Reconstructed reflection response Reconstructed depth image
Passive Seismic Imaging in Complex Media Numerical comparison with varying number of underground sources 6 minutes of white noise recording with 57 subsurface sources Directly modelled reflection response Reconstructed reflection response Reconstructed depth image
Passive Seismic Imaging in Complex Media Numerical comparison with varying number of underground sources 6 minutes of white noise recording with 11 subsurface sources Directly modelled reflection response Reconstructed reflection response Reconstructed depth image
Passive Seismic Imaging in Complex Media Numerical comparison with varying number of underground sources 6 minutes of white noise recording with 6 subsurface sources Directly modelled reflection response Reconstructed reflection response Reconstructed depth image
Green’s function retrieval diffuse wave fields non-diffuse wave fields: representation theory many sources required primaries and multiples (coda) no medium information required Interferometric imaging diffuse or non-diffuse wave fields few sources required primaries only (multiples imaged as ghosts) background medium required Conclusions