Transcript Extended Diffraction-Slice Theorem for Wavepath Traveltime

3D Multisource
Full-Waveform Inversion using
Quasi-Monte Carlo Phase Encoding
Chaiwoot Boonyasiriwat
Jan. 7, 2010
Outline
• Introduction to Multisource Technology
• Phase Encoding
• Multisource Full-Waveform Inversion
• Quasi-Monte Carlo Phase Encoding
• Numerical Results
• 3D SEG/EAGE Overthrust Model
• Summary
• Future Work
• Acknowledgment
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Introduction: Multisource Tech.
• Migration
• Delayed-shot migration (Zhang et al., 2005)
• Random phase encoding (Romero et al., 2000)
• Plane-wave migration (Liu et al., 2006; Shan
and Biondi, 2008; Shan et al., 2009)
• Full-Waveform Inversion (FWI)
• Plane-wave FWI (Vigh and Starr, 2008)
• Random phase encoding (Krebs et al., 2009;
Zhan et al., 2009)
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Single-Source Method
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Multisource Method
Linear Phase Encoding—Planewave Decomposition
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Multisource Method
Random Phase Encoding
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CSG vs SSG
CSG
SSG
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Outline
• Introduction to Multisource Technology
• Phase Encoding
• Multisource Full-Waveform Inversion
• Quasi-Monte Carlo Phase Encoding
• Numerical Results
• 3D SEG/EAGE Overthrust Model
• Summary
• Future Work
• Acknowledgment
7
Conventional FWI
Model
Observed Data
Evaluate misfit function and compute gradient
Perturb Model
Evaluate misfit function
No
Search criterion
No
Yes
Convergence criterion
Yes
Done
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Multisource FWI
Model
Encoded Data
Evaluate misfit function and compute gradient
Perturb Model
Evaluate misfit function
No
Search criterion
No
Yes
Convergence criterion
Yes
Done
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2D Multisource FWI
Krebs Method (ExxonMobil): one SSG,
random source polarity, dynamic encoding
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2D Multisource FWI
Zhan Method (UTAM): multiple SSGs,
random time shift, static encoding, deblurring filter
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3D Multisource FWI
Krebs Source Configuration
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3D Multisource FWI
Closely Packed Source Configuration
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3D Multisource FWI
Loosely Packed Source Configuration
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3D Multisource FWI
Quasi-Monte Carlo Source Configuration
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Static vs Dynamic Configuration
Static
Dynamic
Iteration
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2
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Outline
• Introduction to Multisource Technology
• Phase Encoding
• Multisource Full-Waveform Inversion
• Quasi-Monte Carlo Phase Encoding
• Numerical Results
• 3D SEG/EAGE Overthrust Model
• Summary
• Future Work
• Acknowledgment
15
3D SEG/EAGE Overthrust Model
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Numerical Results
True Velocity Model
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Numerical Results
Initial Velocity Model
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Numerical Results
Velocity Model from Static QMC
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Numerical Results
Velocity Model from Dynamic QMC
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Numerical Results
Velocity Model from Krebs Method
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Outline
• Introduction to Multisource Technology
• Multisource Full-Waveform Inversion
• Numerical Results
• 3D SEG/EAGE Overthrust Model
• Summary
• Future Work
• Acknowledgment
22
Summary
• 3D multisource FWI using multiple SSGs is compared
with multisource FWI using one SSG.
• Using multiple SSGs and a dynamic QMC phase
encoding provides a better-quality velocity model than
a static QMC phase encoding and Krebs method.
• Theoretical speedups need to be verified.
• More reliable timing results will be presented later.
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Outline
• Introduction to Multisource Technology
• Multisource Full-Waveform Inversion
• Numerical Results
• 3D SEG/EAGE Overthrust Model
• Summary
• Future Work
• Acknowledgment
24
Future Work
• Compare various multisource configurations.
• Compare random phase encoding with planewave encoding.
• Apply random time shifts and deblurring filter.
• Apply 3D multisource FWI to field data.
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Acknowledgment
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Sponsors of 2009 UTAM consortium
HPC: Aron Ahmadia and Mark Cheeseman
Shaheen: Iain Georgeson and Jonathan Anderson
Multisource: Ge Zhan and Wei Dai
Workstation: Benoit Marchand
KAUST: Jerry Schuster
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