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Migration Deconvolution vs. Least Squares Migration. Jianhua Yu University of Utah. Outline. Motivation MD vs. LSM Numerical Tests Conclusions. Amplitude distortion. Footprint. Migration noise and artifacts. Migration Noise Problems. Limited Resolution. Migration Problems. Aliasing.
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Migration Deconvolution vs. Least Squares Migration Jianhua Yu University of Utah
Outline • Motivation • MD vs. LSM • Numerical Tests • Conclusions
Amplitude distortion Footprint Migration noise and artifacts Migration Noise Problems
Limited Resolution Migration Problems Aliasing
Improving resolution Suppressing migration noise Computational cost Robustness Motivation Investigate MD and LSM:
Outline • Motivation • MD vs. LSM • Numerical Tests • Conclusions
-1 T T m = (L L ) Ld Reflectivity Seismic data Modeling operator Migration operator Least Squares Migration
T -1 m = (L L ) m’ Reflectivity Migration Section MD deblurring operator Migration Deconvolution
-1 T T LSM: m = (L L ) Ld T -1 m = (L L ) m’ MD: Migrated image Data Solutions of MD vs. LSM
Outline • Motivation • MD vs. LSM • Numerical Tests • Conclusions
Numerical Tests • Point Scatterer Model • 2-D SEG/EAGE overthrust model poststack MD and LSM
Scatterer Model Kirchhoff Migration 1.0 1.0 0 0 0 Depth (km) 1.8
LSM Iter=15 MD 1.0 1.0 0 0 0 Depth (km) 1.8
Numerical Tests • Point Scatterer Model • 2-D SEG/EAGE Overthrust Model Poststack MD and LSM
X (km) 0 7.0 0 KM Depth (km) 4.5 X (km) 0 7.0 0 LSM 10 4.5
X (km) 0 7.0 0 KM Depth (km) 4.5 X (km) 0 7.0 0 LSM 15 4.5
X (km) 0 7.0 0 KM Depth (km) 4.5 X (km) 0 7.0 0 MD 4.5
X (km) 0 7.0 0 LSM 15 Depth (km) 4.5 X (km) 0 7.0 0 MD 4.5
Zoom View KM LSM 15 2 Depth (km) 3.5 LSM 19 MD 2 Depth (km) 3.5
Why does MD perform better than LSM ? X (km) 0 7.0 0 Depth (km) LSM 19 4.5 0 MD 4.5
Outline • Motivation • MD vs. LSM • Numerical Tests • Conclusions
Function Resolution Performance MD = LSM . Conclusions Efficiency MD >> LSM Suppressing noise MD > LSM Robustness MD < LSM
Acknowledgments • Thanks to 2001 UTAM sponsors for their financial support