On-Demand Webinars

BOREHOLE FLOW METER TECHNIQUES:
For Assessing Bedrock Stratigraphy and Fracture Hydraulics

Measuring the vertical movement of water in wells and boreholes can be a key to understanding the subsurface hydraulic environment. Borehole flowmeters can measure both the direction and velocity of vertical flow along well bores, and these flows relate directly to aquifer parameters such as transmissivity, hydraulic conductivity, vertical head profiles, and the presence of fractures or permeable features along boreholes. Quantitative interpretation of borehole flow data can provide estimates of hydraulic parameters and be directly related to hydrostratigraphy.

This webinar will discuss the common types of flowmeters and associated equipment in use today, including both mechanical spinner and heat-pulse systems. Participants will learn the basic theory of operation, pros and cons of various systems, and appropriate application for flowmeter testing. The webinar will address tool calibration and appropriate field procedures for obtaining reliable data. The webinar will also demonstrate data interpretation and presentation methods.

TOPICS:

• Definition of borehole flowmeter testing
• Considerations in flowmeter testing
• The spinner flowmeter – collecting and interpreting data
  • Threshold velocities
  • Logging speeds
  • Problems and pitfalls
    • propeller
    • centralization
  • typical data
  • data processing and interpretation
• The heat-pulse flowmeter –collecting and interpreting data
  • Appropriate flow velocities
  • Theory of operation
  • Determining flow direction
  • Typical data pulses
  • Problems and pitfalls
    • Too little flow
    • Too much flow
  • Data processing and interpretation
• Applications of flowmeter data to hydraulic interpretation
  • Paillet methods
  • Halford methods
• Case study in various bedrock types and conditions

WHAT YOU WILL GAIN:

• Discover the advantages and applications of flow meters
• Learn how to interpret a flow meter log
• Learn how to determine vertical flows and gradients across an aquitard
• Learn common mistakes and how to avoid them

ASK YOURSELF:

• Where is the change in rock mass permeability?
• Is there a hydraulic head drop apparent in these results?
  If so, where is it and what other tools show a change? And if present, how is it related to the geology?
• Where is the change in ambient borehole flow?
• What column (tool) show insignificant relationship to this significant observation?