Thermal Conductivity Meter (TCON)

Overview

Thermal conductivity (k; in W/[m·K]) is the rate at which heat is conducted through a material. At steady state, thermal conductivity is the coefficient of heat transfer (q) across a steady-state temperature (T) difference over a distance (x):

q = k(dT/dx)

Thermal conductivity of Earth materials depends on many factors. At high porosities such as those typically encountered in soft sediment, porosity (or bulk density, water content), the type of saturating fluid, and temperature are the most important factors affecting thermal conductivity. For low-porosity materials, composition and texture of the mineral phases are more important.

Note: instrument is not in continuous operation and is available by request.

Instrument Make and Model

Teka Berlin TK04

Estimated Measurement Time

Sample Preparation: 4 - 12 hours (rock material only)
Measurement Time: 30 - 60 minutes/measurement

Principles & Analytical Capabilities

The Teka Berlin TK04 system determines thermal conductivity based on a transient heat flow method. A line source is heated with constant power while recording source temperature. Thermal conductivity is calculated from the resulting heating curve. TCON data can be acquired using the needle probe method in full-space configuration for whole-round sediment cores, or half-space configuration for consolidated sediments and hard rock samples, after reaching thermal equilibrium in the laboratory.

The TK04 can not be calibrated but the performance of the probes can be evaluated using the provided Macor standards that have known thermal conductivity values.

Data Generated

Data components:

Thermal conductivity mean (W/(m*K)): mean result of successive thermal conductivity observations.
Conductivity std. dev. (W/(m*K)): standard deviation of all valid thermal conductivity observations made on a specific sample.
Measurements (no.): how many observations were made on a sample to satisfy the software variance constraints.
Thermal conductivity observations (W/(m*K)): individual thermal conductivity observations (the number of rows displayed is determined by the number of observations).

Data components:

Results (DAT): tabular file containing measurement replicates and results

Data components:

Data Heating and Evaluation Curve file (DWL): raw data file containing the time-based temperature data and metadata
MDB file (MDB): raw data file readable by TK-04 software
Solutions and LET values file (ERG): instrument generated file with a list of of result solutions

Data Example

Graph of [copy from caption]. — Thermal conductivity measurements from Hole U1436A of IODP Expedition 350 in the Izu-Bonin-Mariana Rear Arc.¹

Procedures & Manuals

References

¹Tamura, Y., Busby, C. J., Blum, P., Guèrin, G., Andrews, G. D. M., Barker, A. K., Berger, J. L. R., Bongiolo, E. M., Bordiga, M., DeBari, S. M., Gill, J. B., Hamelin, C., Jia, J., John, E. H., Jonas, A. S., Jutzeler, M., Kars, M. A. C., Kita, Z. A., Konrad, K., … Yang, A. Y. (2015). IODP Expedition 350 Thermal conductivity [Data set]. Zenodo. https://doi.org/10.5281/zenodo.7502444