1 / 28

REVERSE -TIME DATUMING

REVERSE -TIME DATUMING. M. Zhou Y. Luo (Saudi Aramco). Geology and Geophysics Department University of Utah. Outline. Objective How to Implement Examples Conclusions. Accurate. RTM. Expensive. +. Approx. Phase-shift Kirchhoff. Efficient. Objective. Offset (km).

maja
Download Presentation

REVERSE -TIME DATUMING

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. REVERSE -TIME DATUMING M. Zhou Y. Luo (Saudi Aramco) Geology and Geophysics Department University of Utah

  2. Outline • Objective • How to Implement • Examples • Conclusions

  3. Accurate RTM Expensive + Approx. Phase-shift Kirchhoff Efficient Objective Offset (km) Complex Rough topography Large velocity variation RTD Depth (Km) Less Complex

  4. Outline • Objective • How to Implement • Examples • Conclusions

  5. Implement RTD d(s|x’’) d(s|x’’) d(s|r) g*(r|x’’) d(s|r) d(s|x’’)= d(x’|x’’) S R Depth d(x’|x’’)=g*(s|x’) d(s|x”) x’’ x’ Distance

  6. Implement RTD d(x’|x’’) = g(r|x’’) d(s|r) * = d(x’|x’’) d(s|r) S R g(s|x’) Depth x’’ x’ Target-oriented RTD (Luo , 2002) Distance

  7. Outline • Objective • Implement • Examples • Conclusions 2-D Salt Model Pluto 1.5 (Smarrt Jv.)

  8. 2-D Salt Model Offset (km) Offset (km) 15 0 15 0 Depth(Km) 3 Velocity Model Zero-offset Data

  9. After Redatuming Offset (km) 15 0 Offset (km) 0 15 Depth (Km) 3 Velocity Model Zero-offset Data at datum

  10. 2D Salt Model Offset (km) 0 5 10 15 2 Depth (Km) 3

  11. KM Image After Redatuming Offset (km) 0 5 10 15 2 Depth (Km) 3

  12. KM Image After Redatuming KM Images Before Redatuming Offset (km) 0 5 10 15 2 Depth (Km) 3

  13. KM Image After Redatuming Whole Volume RTM Offset (km) 0 5 10 15 2 Depth (Km) 3

  14. CPU Time Comparison S1400, 2048MB memory KM before datuming 1 (3801 sec) 6.88 (26147 sec) RTD + KM 13.4 (50832 sec) Whole volume RTM:

  15. After Redatuming Offset (km) 15 0 Depth (Km) Offset (km) 0 15 3 Velocity Model Zero-offset Data at datum

  16. Model KM Image After Redatuming Offset (km) 0 5 10 15 3 Depth (Km) 3 KM

  17. KM Before and After Redatuming Offset (km) 0 5 10 15 3 KM Before Depth (Km) 3 KM After

  18. Whole volume RTM KM After Redatuming vs. RTM Offset (km) 0 5 10 15 3 Before Depth (Km) KM After Datum 3 Save 40% w.r.t whole volume RTM

  19. KM After Redatuming Offset (km) 0 5 10 15 3 Shallow Datum Depth (Km) Deep Datum 3

  20. Outline • Objective • Implement • Examples • Conclusions 2-D Salt Model Pluto 1.5 (Smarrt Jv.)

  21. SMARRT JV. Pluto 1.5 Vp model 0 Depth (Km) 9 0 30 Distance (km)

  22. Zero-offset Data 1 Time (Sec) 5 5 25 Distance (km)

  23. Reflectivity Model Below Datum Zero-offset Data After Datuming 0 5 Depth (Km) Time (Sec) 1 7 10 20 Distance (km)

  24. Outline • Objective • How to Implement • Examples • Conclusions

  25. Conclusions • RTD is faster than RTM • RTD helps reveal deeper structure • RTD + KM is cost efficient and provides good depth image

  26. Conclusions • RTD introduces artifacts due to • data boundary

  27. 2000 ms 10 km Courtesy of Yi Luo (Saudi Aramco)

  28. Acknowledgements We thank Utah Tomography and Modeling/Migration Consortium sponsors for their financial support

More Related