Product Category
Borehole Geophysics & Well Logging
Borehole geophysical logging systems and probes from Mount Sopris Instruments, Robertson Geologging, and ALT (Advanced Logic Technology), for groundwater, geotechnical, environmental, and mineral exploration well logging. Available New, Refurbished, Absolute Certified, or Surplus.
What is Borehole Geophysical Logging?
Borehole (or downhole) geophysical logging lowers a sensor probe into a drilled well or borehole on an armored cable, continuously recording one or more physical properties of the surrounding formation and/or the well itself as a function of depth. Unlike surface geophysical methods, borehole logging measures properties directly adjacent to the sensor with high vertical resolution, providing ground-truth data that calibrates and constrains surface survey interpretations, and directly characterizes formation properties, well construction, and fluid conditions at depth.
Common Probe Types
- Natural gamma: Measures naturally occurring radioactivity (mainly from potassium, uranium, and thorium-bearing minerals) to distinguish clay/shale from sand, gravel, or rock — usable in both open and cased boreholes.
- Electrical resistivity/conductivity (fluid & formation): Measures formation resistivity (for lithology and porosity/fluid-saturation estimation) and fluid electrical conductivity within the borehole (for salinity and contamination profiling).
- Caliper: Measures borehole diameter with depth, used to assess well construction, identify washouts or collapse zones, and correct other logs for hole-diameter effects.
- Acoustic/optical televiewer: Produces an oriented, high-resolution image of the borehole wall, used to map fractures, bedding, and structural orientation.
- Flowmeter (spinner or heat-pulse): Measures vertical flow within the borehole, used to identify producing/receiving zones in a well.
- Temperature & fluid conductivity: Profiles borehole fluid properties with depth, useful for identifying inflow zones and groundwater chemistry changes.
System Configuration
A typical system consists of an interchangeable probe (or probe string combining several sensors), an armored logging cable, a winch (manual, powered, or vehicle-mounted), and a surface data-acquisition unit that digitizes and depth-references the signal in real time. Logging speed is a trade-off between survey efficiency and vertical resolution — slower logging speeds resolve thinner features but take longer per well.
Borehole Geophysics Brands We Supply
| Brand | Origin / Parent | Known For | Typical Application |
|---|---|---|---|
| Mount Sopris Instruments | Independent (USA) | Modular logging probes, winches, and surface systems for a wide range of borehole measurements | Groundwater, environmental, geotechnical |
| Robertson Geologging | Independent (UK) | Slimhole logging systems and probes, widely used in mineral exploration drilling | Mineral exploration, groundwater |
| ALT (Advanced Logic Technology) | Independent (Luxembourg) | Acoustic/optical televiewers and specialized logging software | Fracture & structural analysis, engineering |
Condition Tiers for Borehole Logging Equipment
Factory New
Probe, cable, winch, and surface unit direct from the manufacturer, full OEM warranty and factory sensor response certificate.
Refurbished
Probe housing pressure-tested, cable head and winch mechanism inspected, sensor output verified against a known reference before dispatch.
Absolute Certified
Full bench inspection with sensor response verified against traceable reference standards (e.g. a gamma check-source or calibrated caliper jig); calibration certificate issued at handover.
Surplus
Decommissioned or excess logging-company probes, cable, and winches, sold functional and as-is — a common source of spare probes for a multi-parameter string.
Frequently Asked Questions
Can borehole logging probes from different brands share the same winch and surface unit?
Not usually directly — cable head connectors, conductor counts, and telemetry protocols are generally brand-specific, so a probe from one manufacturer typically won't plug into another manufacturer's winch and surface unit without an adapter (if one exists). If you're building or expanding a logging system, tell us your existing equipment and we'll confirm compatibility before recommending Surplus or Absolute Certified additions.
How is a refurbished gamma probe verified before sale?
The probe housing is pressure-tested to confirm it's still sealed for downhole use, and the detector response is checked against a known check-source. Our Absolute Certified tier goes further, verifying count-rate response against a traceable reference source and issuing a calibration certificate documenting the result.
What logging speed should I use for my survey?
It depends on the probe and the resolution you need: gamma and resistivity logs are commonly run at a few meters per minute for good vertical resolution in thin-bedded formations, while caliper or fluid-property logs where thin-feature resolution matters less can often be run faster. Televiewer logging is generally the slowest, since image quality depends on adequate sampling density with depth. We can advise on appropriate logging speed for your target formation and probe type.