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Electrical conductivity measurements of brucite under crustal pressure and temperature conditions

Earth, Planets and Space volume 59, pages 645–648 (2007)Cite this article

Abstract

Hydrous minerals are crucial because their occurrence is associated with seismic activity through the dehydration process that occurs in the earth’s crust and/or mantle. We have developed a technique to observe the dehydration reaction of brucite using electrical conductivity variation under sealed conditions. The electrical conductivity of brucite was measured as a function of temperature. The confining pressure for the measurements was 1 GPa, which represents that of the lower crust. Two types of remarkable electrical conductivity variation were observed. During the first heating, the conductivity of the sample showed a linear variation below 700 K, as was expected from the Arrhenius equation. Once the temperature was increased to near the dehydration boundary, the sample showed a high conductivity. Even though only a small amount of H2O was formed after dehydration, bulk conductivity of the sample varied greatly, presumably caused by a combination of the presence of coexisting solid and fluid phases and a mixed electronic and ionic conduction mechanism operating in the sample.

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Authors and Affiliations

  1. Office of International Relations, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka, 565-0871, Japan

    Kiyoshi Fuji-ta

  2. Institute for Study of the Earth’s Interior, Okayama University, Japan

    Tomoo Katsura & Takuya Matsuzaki

  3. Department of Earth and Planetary Sciences, Tokyo Institute of Technology, Japan

    Masahiro Ichiki

Authors
  1. Kiyoshi Fuji-ta
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  2. Tomoo Katsura
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  3. Takuya Matsuzaki
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  4. Masahiro Ichiki
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Correspondence to Kiyoshi Fuji-ta.

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Fuji-ta, K., Katsura, T., Matsuzaki, T. et al. Electrical conductivity measurements of brucite under crustal pressure and temperature conditions. Earth Planet Sp 59, 645–648 (2007). https://doi.org/10.1186/BF03352725

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  • DOI: https://doi.org/10.1186/BF03352725

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