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Multiple attenuation in the image space. Paul Sava & Antoine Guitton Stanford University SEP. Goal. Method feasible in 3-D Less expensive Dense data requirement Exploit the data/imaging mismatch Data: two-way propagation Migration: one-way extrapolation. Key technology.
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Multiple attenuation in the image space Paul Sava & Antoine Guitton Stanford University SEP paul@sep.stanford.edu
Goal • Method feasible in 3-D • Less expensive • Dense data requirement • Exploit the data/imaging mismatch • Data: two-way propagation • Migration: one-way extrapolation paul@sep.stanford.edu
Key technology • Migration by wavefield extrapolation (WEM) • Angle-domain common-image gathers • High resolution Radon Transforms paul@sep.stanford.edu
The big picture Image Image RT & Mute S/N separation WE migration & ADCIG RT & Mute S/N separation NMO WE prediction Data Data paul@sep.stanford.edu
Multiple attenuation by RTs Moveout analysis NMO Moveout analysis WE migration • S/N separation • RT + Mute • S/N separation • RT + Mute paul@sep.stanford.edu
3-D depth imaging WE migration Multi-arrival Angle-gathers Single-valued Kirchhoff migration Single-arrival Offset-gathers Multi-valued y x g z g Biondi et al. (2003) Stolk & Symes (2002) paul@sep.stanford.edu
Synthetic example: data vs. image CIG CMP paul@sep.stanford.edu
Which Radon transform? g q g(g) z Generic Radon Transform Parabolic Tangent Biondi & Symes (2003) paul@sep.stanford.edu
Synthetic example: RTs Parabolic Tangent paul@sep.stanford.edu
Synthetic example: S/N separation primaries & multiples ART ART + mute multiples primaries paul@sep.stanford.edu
BP synthetic example paul@sep.stanford.edu
BP synthetic example primaries & multiples ART multiples primaries paul@sep.stanford.edu
BP synthetic example: stacks primaries & multiples multiples primaries paul@sep.stanford.edu
GOM example paul@sep.stanford.edu
GOM example: CIG 1 primaries & multiples ART ART + mute multiples primaries paul@sep.stanford.edu
GOM example paul@sep.stanford.edu
GOM example: CIG 2 primaries & multiples ART ART + mute multiples primaries paul@sep.stanford.edu
GOM example paul@sep.stanford.edu
GOM example: zoom 1 primaries & multiples paul@sep.stanford.edu
GOM example: zoom 1 primaries paul@sep.stanford.edu
GOM example: zoom 1 primaries & multiples paul@sep.stanford.edu
GOM example: zoom 1 multiples paul@sep.stanford.edu
GOM example paul@sep.stanford.edu
GOM example: zoom 2 primaries & multiples paul@sep.stanford.edu
GOM example: zoom 2 primaries paul@sep.stanford.edu
GOM example: zoom 2 primaries & multiples paul@sep.stanford.edu
GOM example: zoom 2 multiples paul@sep.stanford.edu
RT comparison Image space RT Data space RT paul@sep.stanford.edu
Discussion PROs Cheap & robust 3-D Simple primaries Migration artifacts CONs Velocity model? Moveout function? Interactive mute Inner angles RT artifacts paul@sep.stanford.edu
Summary Image Image RT & Mute S/N separation WE migration & ADCIG RT & Mute S/N separation NMO WE prediction Data Data paul@sep.stanford.edu
Summary • Multiple attenuation after migration • WE migration • Angle gathers • Cost/accuracy • Complex propagation • Cheap separation • RT limitations • filtering approach paul@sep.stanford.edu