1. 4D Interferometric Traveltime Tomography
Yuqing Chen
King Abdullah University of Science and Technology
11/12/2015

2. Outlines 1.Theory part Numerical Test Problem (also opportunities)
Further plan

3. Theory

4. Theory Pre Fluid Post Fluid
With time elapse , The velocity of the layer changes…

5. Theory Pre Fluid Post Fluid
With time elapse , The velocity of the layer changes…

6. Advantage Multiples are more sensitivity to velocity change.
Eliminate source and receiver statics

7. Method
Instead of Raytracing, using approximate WET (wave path eikonal traveltime inversion) method to implement this method.
Source side traveltime table:
Receiver side traveltime table:

8. Method
Add them together:
Subtract observe time:

9. Method
Cigar
Rabbit ear
Snake

10. Method
Raytracing
AWET

11. Numerical Test

12. Numerical Result

13. Static Test Update first layer Add static in traveltime Residual curve
Similarity

14. First Layer Change Test

15. Second Layer Change Test
Absolute time=
Global velocity anomalies
Differential time=
Local velocity anomalies

16. Second Layer Change Test

17. Both Layer Change

18. (Left) Trace 20 & Residual curve (up)
Both Layer Change
Layer 1
(Left) Trace 20 & Residual curve (up)

19. (Left) Trace 20 & Residual curve (up)
Both Layer Change
Layer 2
(Left) Trace 20 & Residual curve (up)

20. Problem
(or opportunities)

21. Problem 1: Convergence Property
Approximate of Hessian of Multiples
Approximate of Hessian of Reflection
The difference of between the above two Hessian

22. Problem 2 : Traveltime Prediction
The way we predict reflection and multiples

23. Problem 2 : Traveltime Prediction

24. Problem 2 : Traveltime Prediction
Refraction
Refraction-Reflection

25. Problem 2 : Traveltime Prediction
Refraction multiples
Refraction multiples

26. Problem 2 : Traveltime Prediction
Gradient of Multiples
Refraction of Reflection

27. Problem 2 : Traveltime Prediction
Initial model
True model

28. Problem 2 : Traveltime Prediction
Initial model
Inversion result

29. Problem 2 : Traveltime Prediction
(Left) Trace 20 & Residual curve (up)

30. Future Plan

31. Further plan
Real Data Test:
Resonant Multiples
Refraction Multiples