Interlaboratory testing of thermal properties at ambient pressure on reference samples and core samples from the COSC-1 scientific drill hole, central Sweden
Artikel i vetenskaplig tidskrift, 2025

We conducted comparative measurements of thermal properties of samples from nine cores of the ICDP COSC-1 borehole and four widely used rock references, using a steady-state and a transient divided-bar device, a transient plane source device, a modified Ångström device, as well as two optical thermal conductivity scanners. In addition, a caloric method provided benchmark values for specific heat capacity. A complementary thin-section analysis of the COSC-1 samples allowed us to calculate specific heat capacity according to Kopp's law and thermal conductivity according to commonly used mixing models. Our results demonstrate agreement between the various test methods within per cent for about one half of the investigated samples. Furthermore, almost all results for specific heat capacity agree with the predictions of Kopp's law, though the significance of this correspondence is limited owing to large uncertainties in the experimental and theoretical values. The results for thermal conductivity fall within the most extreme theoretical bounds that account for anisotropy but for an amphibolite. Thermal anisotropy seems to contribute significantly to the deviations between results of the different transient methods that, however, cannot be reconciled by the available theoretical relations for apparent thermal conductivity of transversely isotropic materials. The combination of characteristic investigation volume of the individual methods and sample heterogeneity has to be considered responsible for variability of results, too, an issue whose clarification is calling for dedicated numerical modelling in the future, with the prospect to characterize thermal heterogeneity from observed differences.

Heat flow

Europe

Författare

R. Löwe

Bundesgesellschaft für Endlagerung

Ruhr-Universität Bochum

J. Renner

Ruhr-Universität Bochum

C. Pascal

Ruhr-Universität Bochum

Bijan Adl-Zarrabi

Chalmers, Arkitektur och samhällsbyggnadsteknik, Byggnadsteknologi

N. Balling

Aarhus Universitet

T. S. Bording

Aarhus Universitet

TEMcompany Aps.

M. Long

University College Dublin

G. Schwarz

Sveriges Geologiska Undersökning (SGU)

Jan Sundberg

Chalmers, Arkitektur och samhällsbyggnadsteknik, Geologi och geoteknik

JK Innova AB

Geophysical Journal International

0956-540X (ISSN) 1365246x (eISSN)

Vol. 241 1 405-436

Ämneskategorier (SSIF 2025)

Geofysik

Den kondenserade materiens fysik

DOI

10.1093/gji/ggaf046

Relaterade dataset

URI: https://10.0.20.161/zenodo.11141628

Mer information

Senast uppdaterat

2025-03-07