September 21, 20071 SEGD Rev. 3.0 Positioning Subcommittee Barry D. Barrs ExxonMobil

September 21, 2007 1

SEGD Rev. 3.0 SEGD Rev. 3.0 Positioning SubcommitteePositioning Subcommittee

Barry D. Barrs

ExxonMobil


OverviewOverview

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 AccomplishmentsNext Steps


Post OGP – S&P MeetingPost OGP – S&P Meeting

Meeting Attendees – May 1

• Barry Barrs – ExxonMobil - Chair• Bob Firth – Troika • Stewart Levin – Halliburton• Geir Simensen – Statoil• Jan Eikelboom – Shell



Meeting Attendees – May 21

• Barry Barrs – ExxonMobil - Chair• Rune Haglund – WesternGeco • Stewart Levin – Halliburton• Jan Eikelboom – Shell• John Conner - EnSoCo



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



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



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



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



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


Post EAGE MeetingPost 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



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



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



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


Positioning Working GroupPositioning Working Group

Meeting Attendees – August 1

• Barry Barrs – ExxonMobil • John Conner – EnSoCo• Roger Lott – Retired BP• Victor Ramirez – CGGVeritas• Jim Cain – Cain & Barnes



Meeting Attendees – September 5

• Barry Barrs – ExxonMobil • Geir Simensen – Statoil• John Conner – EnSoCo• Victor Ramirez – CGGVeritas• Jim Cain – Cain & Barnes



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



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



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



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


Current AccomplishmentsCurrent Accomplishments

See Current Appendix “X” for SEGD3


Next StepsNext 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


Next StepsNext Steps

Have a follow-up Meeting with full Positioning Subcommittee to review all recommendations

Documents

September 21, 20071 SEGD Rev. 3.0 Positioning Subcommittee Barry D. Barrs ExxonMobil