Practical Well Log Standards for Acquisition Curves

1
Practical Well Log Standardsfor Acquisition
Curves

• Paul Maton, POSCJim Theriot, POSCAlan Doniger,
  POSCApril 2005

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Outline

• Business Drivers, Challenges
• Phase 1 outcomes
• Phase 2 approaches, results, examples
• Next Steps

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Well Logs Business Issues

• Huge numbers of curves (information overload)
• Most oil company customers only load a small
  sub-set of
• curves into their data stores

• Complex naming at BOTH Curve and Tool level
• Confusing even to petrophysicists
• Others got lost years ago!

• Hard to find up to date information in public
  domain
• Isolated lists, complex language

Expert (petrophysicist) and generalist users have
different requirements
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Information Overload - Business Value
Note Business Value does not take account of
usage. It deals with the average case
Load Frequency
High Business Value Most oil company customers
only load a small sub-set of curves into their
data stores
Most Commonly Loaded
Medium Business Value Loaded for specialist
applications
Rarely Loaded
Loaded Curve Names
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Log Data Management Challenges

• Nomenclature
• Logging companies Vocabularies
• Oil companies Dictionaries
• Classification for
• Tools
• Curves
• Value
• Who uses ...
• Which logs...
• How often ...
• For what ...

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PWLS Version 1

• Classified 2500 curves for 100 tools from 3
  logging companies
• Defined business value high, medium, low

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PWLS Version 2 Objectives

• Clarify and refine Version 1 results
• Initial focus on two primary use cases
• Classify acquisition curve instances based on
  logging company mnemonics
• Use curve classifications to search for relevant
  acquisition curve instances
• Additional areas of work
• Recommended mnemonics for oil company generated
  curves joined and interpreted
• Classification of well log services and tools,
  e.g. for log header classification

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Generic Service/Tool Class
Generic Curve Class
Company
Service Class
Company Channel
Tool Series
Service-Channel Xref
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Channel, Curve and Property
Industry nomenclature
Companynomenclature
Maps to
Subset of
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Curve Class Attributes

• What is the object (or thing) whose properties we
  are measuring?
• Formation, casing, cement, wellbore, acquisition,
  etc.
• What (pure) property of the object are we
  measuring?
• Density, porosity, velocity, etc.
• What technique are we using to make the
  measurement (with the tool)?
• Neutron, acoustic, etc.
• Modifiers (or qualifiers) qualifying the (pure)
  Property
• Deep / shallow maximum / average / minimum, etc.
• Function
• Mathematical derivation / calculation, e.g.
  ratio, std. Deviation
• Generic Curve Name
• Composite tag based the most important
  attribute value used only for the small subset of
  highest value types of curves, e.g. neutron,
  resistivity

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Some Company Curve Classes
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More Company Curve Classes
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Channel, Curve Example 1
Industry nomenclature
Companynomenclature
Company Channel Class
Curve Class
Maps to
Generic Name Gamma_Ray--------------------------
------------------ Object Formation
Property Gamma Ray
Technique -Modifier(s) -Function -
RP66 Org code 150Co.
Mnemonic GRDescription
Gamma RayClassification Gamma_Ray
Units Class API_Gamma_Ray
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Channel, Curve Example 2
Company nomenclature
Industry nomenclature
Company Channel Class
Curve Class
Maps to
Generic Name Electromagnetic_Caliper------------
--------------------------------------- Object B
orehole Property Caliper
Technique Electromagnetic Modifier(s) -
Function -
RP66 Org code 440Co.
Mnemonic PCALDescription
Caliper from Phase Shift
Imbalance Business Value
HighClassification Electromagnetic
_Caliper Units Class
Cylinder_Diameter
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Links

• PWLS General Web Link
• Property Type Browser
• Company Data Views
• Industry Data Views
• Channel to Curve Class Browser
• Schema for PWLS Reference Data

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Current Focus Usage

• Users
• Oil companies
• Log analysts, Consultants
• Data management repositories, companies
• Suppliers
• Logging contractors (Acquisition, Processing )
• Software developers and vendors
• Evolve
• User communities use PWLS and provide feedback
• Revise specifications and implementations
• Maintain Property, Curve and Tool catalogues