دورية أكاديمية
Pressure dependence of electrical conductivity in forsterite
| العنوان: | Pressure dependence of electrical conductivity in forsterite |
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| المؤلفون: | Yoshino, Takashi, Zhang, Baohua, Rhymer, Brandon, Zhao, Chengcheng, Fei, Hongzhan |
| المصدر: | Journal of Geophysical Research. Solid Earth |
| بيانات النشر: | American Geophysical Union |
| سنة النشر: | 2017 |
| المجموعة: | Okayama University Scientific Achievement Repository / 岡山大学学術成果リポジトリ |
| الوصف: | Electrical conductivity of dry forsterite has been measured in muli-anvil apparatus to investigate the pressure dependence of ionic conduction in forsterite. The starting materials for the conductivity experiments were a synthetic forsterite single crystal and a sintered forsterite aggregate synthesized from oxide mixture. Electrical conductivities were measured at 3.5, 6.7, 9.6, 12.1, and 14.9 GPa between 1300 and 2100 K. In the measured temperature range, the conductivity of single crystal forsterite decreases in the order of [001], [010], and [100]. In all cases, the conductivity decreases with increasing pressure and then becomes nearly constant for [100] and [001] and slightly increases above 7 GPa for [010] orientations and a polycrystalline forsterite sample. Pressure dependence of forsterite conductivity was considered as a change of the dominant conduction mechanism composed of migration of both magnesium and oxygen vacancies in forsterite. The activation energy (ΔE) and activation volume (ΔV) for ionic conduction due to migration of Mg vacancy were 1.8–2.7 eV and 5–19 cm3/mol, respectively, and for that due to O vacancy were 2.2–3.1 eV and −1.1 to 0.3 cm3/mol, respectively. The olivine conductivity model combined with small polaron conduction suggests that the most part of the upper mantle is controlled by ionic conduction rather than small polaron conduction. The previously observed negative pressure dependence of the conductivity of olivine with low iron content (Fo90) can be explained by ionic conduction due to migration of Mg vacancies, which has a large positive activation volume. |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| تدمد: | 2169-9313 |
| العلاقة: | https://ousar.lib.okayama-u.ac.jp/files/public/5/55450/20171031102716206003/J_Geophys_Res_122_158.pdfTest; AA10819743; https://ousar.lib.okayama-u.ac.jp/55450Test |
| الإتاحة: | https://doi.org/10.1002/2016JB013555Test https://ousar.lib.okayama-u.ac.jp/files/public/5/55450/20171031102716206003/J_Geophys_Res_122_158.pdfTest https://ousar.lib.okayama-u.ac.jp/55450Test |
| حقوق: | https://creativecommons.org/licenses/by-nc-nd/4.0/deed.jaTest |
| رقم الانضمام: | edsbas.9CFC2D21 |
| قاعدة البيانات: | BASE |
| تدمد: | 21699313 |
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