SEGD Rev. 3.0 Positioning Subcommittee

1. SEGD Rev. 3.0 Positioning Subcommittee Barry D. Barrs ExxonMobil

2. Overview • Post OGP – S&P Meeting • Summary of Meetings - 5/1 & 5/21 • Post EAGE Meeting • Summary of Meeting - 7/25 • Positioning Working Group • Summary of Meetings - 8/1 & 9/5 • Current Accomplishments • Next Steps

3. Post OGP – S&P Meeting • Meeting Attendees – May 1 • Barry Barrs – ExxonMobil - Chair • Bob Firth – Troika • Stewart Levin – Halliburton • Geir Simensen – Statoil • Jan Eikelboom – Shell

4. Post OGP – S&P Meeting • Meeting Attendees – May 21 • Barry Barrs – ExxonMobil - Chair • Rune Haglund – WesternGeco • Stewart Levin – Halliburton • Jan Eikelboom – Shell • John Conner - EnSoCo

5. Post OGP – S&P Meeting • Summary of Meetings • Much discussion concerning what type of positioning data is needed in SEGD • Planned Positions • As-shot • Measured • Source/Receiver • Sercel has a proprietary format that captures this type of information

6. Post OGP – S&P Meeting • Summary of Meetings • Concern that multiple position types might lead to wrong positioning data being used • Proper tagging of the different types could be used as well as time stamps to help with this problem

7. Post OGP – S&P Meeting • Summary of Meetings • UKOOA P1/90 in SEGD General Header • UKOOA P2/94 in SEGD General Trailer • No intention of the positioning data in SEGD to replace UKOOA P1, P2, or SPS • Ancillary Data Standard (ADS) Format • ADS provides a means of capturing during acquisition and in one file all ancillary data pertaining to a 3D geophysical survey

8. Post OGP – S&P Meeting • Summary of Meetings • (ADS) Format • Any data could be recorded and transferred in a standardized way • P1/90 and P2/94 files could be treated as chunks when incorporated into a metafile • So why is ADS format not used more? • Some felt it was to complex and that is the reason it is not used more

9. Post OGP – S&P Meeting • Summary of Meetings • (ADS) Format • Also the ADS format does not allow for the seismic to be stored • Could the ADS format be embedded into the SEGD? Our understanding is no • We need feedback from industry processors on what positioning they would like to have

10. Post EAGE Meeting • Meeting Attendees – July 25 • Barry Barrs – ExxonMobil - Chair • Jill Lewis – Troika • Bob Firth – Troika • Chris Frew - Troika • Stewart Levin – Halliburton • Geir Simensen – Statoil • Jan Eikelboom – Shell • John Conner - EnSoCo

11. Post EAGE Meeting • Summary of Meeting • Update on EAGE meeting provided by Stewart and Jill • From last meeting – What does Processing want to see • Final Positioning data captured in a manner to help streamline the processing

12. Post EAGE Meeting • Summary of Meeting • SEGD3 is intended as a write once format as close to real-time as possible • The coordinate data is the best approximation at the recording epoch • Automating the ability to populate the SEGY format

13. Post EAGE Meeting • Summary of Meeting • One suggestion for automating was to look at App. D of SEGY1 for defining the coordinate data • Smaller Working Group of positioning experts formed to investigate modifying App. D of SEGY1 for SEGD3 use • Decision made to just work SEGD3 for now and address UKOOA formats later

14. Positioning Working Group • Meeting Attendees – August 1 • Barry Barrs – ExxonMobil • John Conner – EnSoCo • Roger Lott – Retired BP • Victor Ramirez – CGGVeritas • Jim Cain – Cain & Barnes

15. Positioning Working Group • Meeting Attendees – September 5 • Barry Barrs – ExxonMobil • Geir Simensen – Statoil • John Conner – EnSoCo • Victor Ramirez – CGGVeritas • Jim Cain – Cain & Barnes

16. Positioning Working Group • Summary of Meetings • Working group feels App. D is perfect for defining the coordinate data • We need to define precision of the coordinates • Need the ability to define the CRS both implicitly and explicitly

17. Positioning Working Group • Summary of Meetings • Vertical Component in App. D not well defined • Transformation Stanza needs to be added • Maybe a stanza that addresses Engineering/Township-Range systems

18. Positioning Working Group • Summary of Meetings • Any changes made to App. D for SEGD3 use should be considered also for SEGY1 • Both Easting / Northing and Latitude / Longitude coordinates should be included for all points in SEGD3 • If not both, then a test point example should be included

19. Positioning Working Group • Summary of Meetings • Add more examples beyond the ones provided for in SEGY1 • Some concern about backward compatibility with existing SEGY1 • For SEGD3 use delete section D2, D3, D5, D6 and D7

20. Current Accomplishments • See Current Appendix “X” for SEGD3

21. Next Steps • Working Group to review changes / modifications to date • Incorporate recent discussions with Stewart Levin on precision in the new Appendix • Determine what coordinates need to be captured in General Header

22. Next Steps • Have a follow-up Meeting with full Positioning Subcommittee to review all recommendations