University of British Columbia SLIM Rajiv Kumar Affordable omnidirectional subsurface extended image volumes Released to public domain under Creative Commons license type BY (https://creativecommons.org/licenses/by/4.0). Copyright (c) 2015 SLIM group @ The University of British Columbia.
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Rajiv Kumar WEMVA Workshop · Rajiv Kumar Affordable omnidirectional subsurface extended image volumes ... Kumar et. al. ’14 minimize Ee 1 2 kF (Ee ) P k2 F, F (Ee)=P r H 1 EW T
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Released to public domain under Creative Commons license type BY (https://creativecommons.org/licenses/by/4.0).Copyright (c) 2015 SLIM group @ The University of British Columbia.
- we combine SRME within the extended imaging condition
Motivation
35
Verschuur et. al. ’92
Extended imaging with multiples
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eE = EW = H�1PTs (Q� P )P ⇤PrH
�1W
: areal source
: total upgoing wavefieldP
(Q� P )
where
Least-square extended imaging
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where
Kumar et. al. ’14
minimizeeE
1
2kF( eE)� Pk2F ,
F( eE) = PrH�1EWTH�1PT
s (Q� P ),
Velocity model
True model Initial model
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Least-squares RTM images
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Primary + multipleswith areal sources
Primary only40
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Primary + multipleswith areal sources
Conclusions
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Multiples provide extra illumination that can complement primaries.
Multiples can be used with primaries to form subsurface image gathers via least-squares inversion.
Acknowledgements
This work was in part financially supported by the Natural Sciences and Engineering Research Council of Canada Discovery Grant (22R81254) and the Collaborative Research and Development Grant DNOISE II (375142-‐08). This research was carried out as part of the SINBAD II project with support from the following organizations: BG Group, BGP, BP, CGG, Chevron, ConocoPhillips, ION, Petrobras, PGS, Statoil, Total SA, WesternGeco, and Woodside.
Thank you for your attention ! https://www.slim.eos.ubc.ca/