Technical Team

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Technical Team

• WITSML SIG
• Paris 16 May 2007

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Technical Team

• Representatives mainly from service companies
• Energistics (Gary) keep a global issue list
• Monthly conference calls
• 6-monthly face-to-face meetings

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Technical TeamExtended Queries Log Pass

• Extended Queries
• Current WITSML queries are for exact match to a
  query template
• ltnamegt123-45/36lt/namegt
• ltdepth uommgt123.45lt/namegt
• Need to be able to use wild card match for
  strings or gt lt for numeric datetime values
• WITSML 1.1 defined an extended query syntax for
  alpha and numeric items
• ltnamegtSEL(123)lt/namegt
• ltmdgtSEL(gt123.4)lt/mdgt
• This was not considered a part of the standard
  and not uniformly adopted
• PRODML is also looking into similar capabilities
• Want to be able to use an appropriate industry
  standard if appropriate
• SQL, XMLQuery etc.
• WITSML and PRODML will work to a common solution
• Log Pass/Trip
• Issue is to be able to properly organize data
  from multiple passes through the same formation
• WITSML log object does not currently provide
  enough information to define the number and type
  of passes through a depth section
• Proposed to add pass number and passType to log
  and wellLog objects in future version (probably
  1.4)

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Technical Team WITS Data

• WITS Data in Realtime?
• Need to ba able to provide an easy upgrade path
  for current providers of WITS level 0 data
• Use HTTP POST instead of custom socket
  connections
• Use WITSML log object
• Define some standard configurations of log
  objects based on WITS with the following changes
• WITS survey, geology, drill string, casing,
  survey, operations records replaced by WITSML
  mudLog, tubular, wellboreGeometry, trajectory and
  opsReportrecords
• WITS log objects replace most of the sequential
  records
• Need to re-define the LWD records to account for
  different sensor at different depths
• Also need to accommodate image data for LWD data

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Technical Team Time Zones

• Timezone issues
• How to handle date/time information as it passes
  from initial provider through one or more
  aggregation servers to end user applications?
• Normally want to see data in time zone of
  original well site e.g. for relating to daily
  reporting intervals
• Well object includes a time zone for the rig
• Recommend always including time zone offset in
  any time stamps
• 2007-05-16T0916360600
• If offset is not specified, assume rig time.
• Issues under discussion
• What happens if we change time zone during a log?
• How to handle clock changes when we know that LWD
  tools often run across daylight time zone
  changes?

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Technical TeamUse Case Profiles

• Need to stay SOA, web services compliant
• Must be XML schema compliant in all web service
  requests
• Need to have at least 4 schemas per object
• Normative schema all elements are optional
• AddToStore schema defines basic required set of
  data
• Query schema
• Returned object schema
• Total Proposals
• Geodetics
• Wellbore Positioning Uncertainty
• Both priority for v1.4

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Technical Team Other Issues

• Lithology Qualifiers
• Can apply to a depth interval or at a single
  depth
• Some qualifiers occur at a point, some over a
  range
• Comma delimiters
• Short term remove commas
• Longer term specify an encoding technique
• Embedded Objects
• Intellifield implemented attachment object with a
  reference back to original data object w/ base64
  encoding and file type
• Similar object reference to message object
• Can handle multiple attachments to the same
  object
• Needed for state regulatory data
• WMLS prefix
• WMLS_DeleteFromStore is bigger than 16 chars
• Work-around ignore 16 char limitation
• Different implementations
• Bug fix go with WMLS_XXX and increase string
  size to 64

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Technical Team Other Issues

• Change Log
• Should objectType and dTimLastChanged be
  mandatory?
• Same as discussed earlier. Mandatory for
  AddToStore use case, optional for query or
  returned value.
• Error messages from WITSML servers
• Add a new error code for permission denied for a
  SOAP operation
• Implement as suggested error code 206
• Do we need a new method GetPermissions?
• How to detect changes in realtime data
• Add new element dTimHeaderLastChanged to realtime
  object. Yes
• New use case for when a log structure changes in
  real time
• Need to query server to find the current growing
  logs

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Technical Team

• If you want to contribute join the SIG!
• Questions?