DwpD Ltd. specializes in

  • Along-hole depth
  • Determining requirements
  • Measurement and correction
  • Uncertainty
  • Process, audit and training

Why bother ?

  • One end of the spectrum:
    • “We never have a depth problem …”
    • Until “the problem” occurs:
  • Then the other end of the spectrum:
    • “We had no end of depth correlation problems on the recent XXX intersect P&A well”
    • “The FWL’s don’t agree across the reservoir”
    • “The horizons just don’t match”
    • “We are not actually sure if there is a fault”
    • “Maybe the depth is wrong ...”

Accuracy expectations

  • How do we define expectations for along-hole depth measurement accuracy in different domains ?

Accuracy Components

  • Requirements ! (no requirements = no accuracy !)
  • Measurement methodology
  • Calibration system
  • Correction model and calculation
  • Uncertainty model and calculation

Basic uncertainty relationship

  • Accuracy = proportion of a result
  • Uncertainty = result value 

Calibration accuracy

  • Measurement standards
  • Calibration variables
  • Environmental effects
  • Measurement effects
  • Shelf life

Correction calculation parameters

  • Thermal expansion
  • Elastic stretch
  • Other corrections

...

View the entire Presentation:

Managing Along-hole Depth Measurement Uncertainty

Harold Bolt (Speaker), Depth Solutions

 

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