Measurement of thermal diffusivity of rocks at high pressure
A method for measurement of thermal diffusivity at high hydrostatic pressure was developed by adapting a radial symmetry heat flow method wherein a sinusoidal heat wave is applied to the cylindrical surface of the sample. The accuracy of the measuring system was tested using Pyroceram 9606. Data obtained were within 5% of published values at all temperatures to 400/sup 0/C and no dependence upon pressure was observed. Thermal diffusivity of three crystalline igneous rock specimens was measured at temperatures from 32 to 400/sup 0/C and pressures from 0.1 to 200 MPa. The results for Creighton quartz diorite showed only limited temperature and pressure dependence. In the case of Stripa and Westerly granites, this dependence was found to be more substantial. Thermal diffusivity of Stripa granite decreased by more than 50% from 32 to 400/sup 0/C and that of Westerly granite decreased by approximately 40% over the same range. At 32/sup 0/C and 200 MPa, thermal diffusivity for both rocks was higher by approximately 10% than that measured at 0.1 MPa. At higher temperatures the difference in thermal diffusivity between the two pressure levels increased. An anomaly was observed in Stripa and Westerly granite in the temperature range 32 to 65/sup 0/C: thermal diffusivity increased with increasing temperature. The anomaly is consistent with recently observed thermal expansivity in these rocks as a function of pressure and temperature.
- Research Organization:
- Department of Energy, Mines and Resources, Ottawa, Ontario (Canada). Canada Centre for Mineral and Energy Technology; Lawrence Livermore National Lab., CA (USA)
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 6851172
- Report Number(s):
- UCRL-87217; CONF-820985-2; ON: DE83003879
- Resource Relation:
- Conference: 8. European conference on thermophysical properties - high temperatures high pressure, Baden-Baden, F.R. Germany, 27 Sep 1982
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
GRANITES
THERMAL DIFFUSIVITY
ACCURACY
EXPERIMENTAL DATA
MEASURING METHODS
PRESSURE DEPENDENCE
TEMPERATURE DEPENDENCE
DATA
IGNEOUS ROCKS
INFORMATION
NUMERICAL DATA
PHYSICAL PROPERTIES
PLUTONIC ROCKS
ROCKS
THERMODYNAMIC PROPERTIES
580300* - Mineralogy
Petrology
& Rock Mechanics- (-1989)