Multiple attenuation in the image space Paul Sava & Antoine Guitton Stanford University SEP paul@sep.stanford.edu

Goal Method feasible in 3-D Exploit the data/imaging mismatch 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 Data NMO RT & Mute WE migration & ADCIG Image Data S/N separation WE prediction S/N separation 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 Angle-gathers Kirchhoff migration Multi-arrival Angle-gathers Single-valued Kirchhoff migration Single-arrival Offset-gathers Multi-valued g Biondi et al. (2003) Stolk & Symes (2002) z x y paul@sep.stanford.edu

Synthetic example: data vs. image CMP CIG paul@sep.stanford.edu

Which Radon transform? Generic Radon Transform Parabolic q Tangent g(g) g z 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 paul@sep.stanford.edu

GOM example paul@sep.stanford.edu

GOM example: CIG 2 primaries & multiples ART ART + mute multiples 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 CONs Cheap & robust 3-D Simple primaries Migration artifacts CONs Velocity model? Moveout function? Interactive mute Inner angles RT artifacts paul@sep.stanford.edu

Summary Data NMO RT & Mute WE migration & ADCIG Image Data RT & Mute S/N separation WE prediction S/N separation paul@sep.stanford.edu

Summary Multiple attenuation after migration Cost/accuracy WE migration Angle gathers Cost/accuracy Complex propagation Cheap separation RT limitations filtering approach paul@sep.stanford.edu