1. Prestack Migration Deconvolution in Common Offset Domain Jianxing Hu University of Utah

2. Outline MotivationMotivation MethodologyMethodology Numerical TestsNumerical Tests ConclusionsConclusions

3. Motivation Computational efficiencyComputational efficiency Improve data quality for AVO and seismic attribute analysis Improve data quality for AVO and seismic attribute analysis

4. Motivation Seismic Trace Migration Ellipse Receiver Source Interface1 Interface2 Incorrect Contribution Actual reflection point

5. Advantages COG is natural domain for AVO analysisCOG is natural domain for AVO analysis Traces in COG domain satisfies the lateral-shift invariance approximation in MDTraces in COG domain satisfies the lateral-shift invariance approximation in MD

6. Outline MotivationMotivation MethodologyMethodology Numerical TestsNumerical Tests ConclusionsConclusions

7. Methodology Calculation in COG DomainCalculation in COG Domain Generate Coefficient Matrix of MD System EquationGenerate Coefficient Matrix of MD System Equation Regularization of MD System EquationRegularization of MD System Equation Equation SolverEquation Solver

8. Migration Green’s Function in COG Domain Point Scatterer Sources Receivers

9. An Example of Migration Green’s Function in COG Domain 0 2 X (km) 0 2 Depth (km)

10. Outline MotivationMotivation MethodologyMethodology Numerical TestsNumerical Tests ConclusionsConclusions

11. Comparison of Migration and MD Images Prestack Prestack COG COG Migration Migration Image Image 0-450 m 0-450 m MD Image 0 4 X (km) X (km) 20 20 Depth (km) Depth (km) 0 0 4 X (km) X (km) 20 20 Depth (km) Depth (km) 0

12. Comparison of Migration and MD Images Prestack COG Migration Image Prestack COG Migration Image 0 - 450 m 0 - 450 m Prestack COG MD Image Prestack COG MD Image 0 - 450 m 0 - 450 m X (km) Depth (km) 2 4 2 4

13. Comparison of Migration and MD Images Prestack Prestack COG COG Migration Migration Image Image 1500-1950 m 1500-1950 m MD Image 0 4 X (km) X (km) 20 20 Depth (km) Depth (km) 0 0 4 X (km) X (km) 20 20 Depth (km) Depth (km) 0

14. Comparison of Migration and MD Images Prestack COG Migration Image Prestack COG Migration Image 1500 - 1950 m 1500 - 1950 m Prestack COG MD Image Prestack COG MD Image 1500 - 1950 m 1500 - 1950 m X (km) Depth (km) 2 4 2 4

15. Comparison of Migration and MD Images Prestack Prestack COG COG Migration Migration Image Image 2500-2950 m 2500-2950 m MD Image 0 4 X (km) X (km) 20 20 Depth (km) Depth (km) 0 0 4 X (km) X (km) 20 20 Depth (km) Depth (km) 0

16. Comparison of Migration and MD Images Prestack COG Migration Image Prestack COG Migration Image 2500 - 2950 m 2500 - 2950 m Prestack COG MD Image Prestack COG MD Image 2500 - 2950 m 2500 - 2950 m X (km) Depth (km) 2 4 2 4

17. Comparison of Migration and MD Images Prestack Prestack COG COG Migration Migration Image Image 3500-3950 m 3500-3950 m MD Image 0 4 X (km) X (km) 20 20 Depth (km) Depth (km) 0 0 4 X (km) X (km) 20 20 Depth (km) Depth (km) 0

18. Comparison of Migration and MD Images Prestack COG Migration Image Prestack COG Migration Image 3500 - 3950 m 3500 - 3950 m Prestack COG MD Image Prestack COG MD Image 3500 - 3950 m 3500 - 3950 m X (km) Depth (km) 2 4 2 4

19. Regularization of MD System Equations Prestack Prestack COG COG Migration Migration Image Image 0-450 m 0-450 m MD Image 0 4 X (km) X (km) 20 20 Depth (km) Depth (km) 0 0 4 X (km) X (km) 20 20 Depth (km) Depth (km) 0

20. Outline MotivationMotivation MethodologyMethodology Numerical TestsNumerical Tests ConclusionsConclusions

21. Conclusions Works well on 2-D synthetic prestack data Improves resolution, attenuates artifacts and corrects amplitude distortions Effective implementation of prestack MD

22. Future Works Quantitatively analyze the MD in AVO character improvement Test COG Prestack MD in 2-D and 3-D field data

23. Acknowledgement Thank 2000 UTAM sponsors for their financial supportThank 2000 UTAM sponsors for their financial support