DLL3 Probe Image


The QL40-DLL3 Dual Laterolog tool provides a time multiples dual spacing focused resistivity measurement with two different depths of investigation, Shallow LL3S and Deep LL3D resistivity in Ohm.m. It is characterized by an excellent vertical resolution in comparison with traditional Normal Resistivity tools, making it ideal for bed-boundary and thickness analysis.

The QL40-DLL3 tool is stackable within the Quick Link (QL) product line or it can be run as a standalone tool.


  • Bed boundary analysis
  • Facies changes
  • Geological formation properties
  • Identification of hydrostratigraphic units
  • Aquifer thickness
  • Water quality
  • Identification of hydrocarbon intervals
  • Detection of ore body zones
  • Identification of fractures

Operating Conditions

Borehole Fluid
[X] Water
[X] Mud
[_] Dry

[X] Uncased
[_] PVC Borehole
[_] Steel

[_] Required
[X] Non-Necessary

Features & Benefits

  • Unparalleled thin bed analysis
  • Can be used as normal resistivity tool, giving two depths of investigation
  • Operates on any standard wireline (Mono, 4, 7 conductor, or Coax)
  • Can be combined with other logging tools of the QL product line or operated as a standalone tool.
  • Measurements are accurate and consistent.

DLL3 Dual Laterolog Comparison Example

Specifications – Metric/English

Specification Metric Imperial
Diameter 43 mm 1.7″
Length 2.75 m 108″
Weight 14 Kg 30.9 lbs.
Max. Temp. 70ºC 158ºF
Max. Pressure 200 bar 2900 psi


Sensor: Stainless steel electrodes
Maximum Injection Power: 5.5 W
Resistivity Range: 1 to 50,000 Ohm-m
Resistivity Accuracy: 1% between 10 and 1,000 Ohm.m
Resistivity Accuracy: < 5% between 1,000 to 10,000 Ohm.m
Resistivity Accuracy: <15% between 10,000 to 50,000 Ohm.m

QL Stack Possibilities

  • QL40DLL3 + QL40GR (Gamma) + QL40MGS (Magnetic Susceptibility): Mining, Exploration
  • QL40DLL3 + QL40GR (Gamma) + QL40OBI (Optical Televiewer): Exploration, Bedding Planes, Fractures in Air or Clear Water
  • QL40DLL3 + QL40GR (Gamma) + QL40ABI (Acoustic Televiewer): Exploration, Bedding Planes, Fractures in Fluid-filled boreholes
  • QL40DLL3 + QL40GR (Gamma) + QL40FTC (Fluid Res, Temp): Hydrogeologist’s Tool, Groundwater exploration and assessment


QL40-DLL3 Dual Laterolog Probe Brochure
User Guide

Print Friendly, PDF & Email