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DOE OSTI · 1780913

Directional Cooling-Induced Fracturing Westerly Granite Test Results

Nakagawa, Seiji
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Abstract

Directional Cooling-Induced Fracturing (DCIF) experiments were conducted on a short, cylindrical sample of Westerly granite (diameter = 4 inches, height ~ 2 inches). Liquid nitrogen was poured in a copper cup attached to the top of the sample, and the resulting acoustic emissions (AEs) and temperature changes on the surface of the sample were monitored. The obtained AEs were used to determine the microcracking source locations and amplitude, and the associated moment tensors. Included in this submission is an animation of the AEs, a graphic displaying the temperature changes, and the measured data.

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15 GEOTHERMAL ENERGYacoustic emissionsdirectional coolingdirectional cooling-induced fracturingfracturegeophysicsgeothermalgraniteinduced fracturinglaboratory experimentliquid nitrogenmicrocrackingmoment tensorseismicstimulationstresstemperaturetemperature changesthermalthermal crackingtomographyvelocitywellboreWesterly granite

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Nakagawa, Seiji. 2020-12-18. Directional Cooling-Induced Fracturing Westerly Granite Test Results. https://doi.org/10.15121/1780913

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