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TCDS-LU (Logging tool)

Model id: Robertson Geologging Temperature/Conductivity with natural gamma


  • electric mud resistivity or mud conductivity
  • temperature
  • total natural gamma

Purpose: absolute temperature, fluid conductivity, natural gamma

Description: This probe combination provides a continuous, depth-based measurement of fluid temperature and conductivity. Both parameters can be output in absolute and in differential forms. A natural gamma detector is available for correlation purposes. The sensors are located in an insulated housing at the base of the probe. During logging, borehole fluid flows freely through ports on the side and base of this housing and over the sensors. The temperature measurement uses a high-sensitivity semiconductor transducer. The conductivity cell comprises three carbon contact-rings driven by a constant-voltage source of alternating polarity to avoid cell polarisation effects.

Characteristics: Conductivity range: 50 to 50,000 μS/cm


Vertical resolution:0.010 m
Typical logging speed:10.00 m/min
Maximum pressure:20.0 MPa
Maximum temperature:70℃
Required boreholefluid:
conductive liquidThe borehole has to be filled with a conductive liquid.
Type of datatransfer:
cableData are transferred in real time via a cable.
Required type of logging cable:
4 conductorA logging cable with 4 conductors.
Required cablehead:
GO4Connector according to GO 4 standard (4 conductors).
Implement search on winches with this cable head.
Type of signal:
digitalDigital signal transmission.
Acquisitionsystem (recommended):RG-LU
Length:2.35 m
Maximum diameter:0.038 m
Weight:7.7 kg
Belongs to toolstring:
standaloneA stand alone tool that cannot be integrated in a tool string.
Usage conditons:Commercial usage allowed/welcome.
Additional usage conditions:Logging as service by Lund University

Operator and contact:

Operator:Lund University, Engineering Geology
Contact person:Per-Gunnar Alm
Telephone:+46 462228992
Address: John Ericssons väg 1
223 63 Lund, Sweden

End of I-EDDA database record