Electric conductivity measurement of the Earth's materials

地球材料的电导率测量

• 批准号: 13440164
• 负责人: KATSURA Tomoo
• 金额: $ 9.6万
• 依托单位: OKAYAMA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-13440164/
• 关键词: electrical conductivity; Hidaka metramorphic; connectivity; iron-iron sulfide; ilmenite; activation energy; activation volume; perovskite; 高圧高温発生装置; 下部マントル; 橄欖岩; Fe-S; ブルーサイト

We measured electrical conductivity of granulite from Hidaka metramorphic belt, Hokkaido, Japan. From the experimental results, we estimated the temperature of the high resistance region at depth of 10-30 km to be 600℃.We conducted experiments to estimate connectivity of iron-iron sulfide melts in dunite and lherzolite matrixes by means of electrical conductivity measurement. From this series of experiments, we found that iron-iron sulfide melt connects if its volume proportion is more than 5 %. Therefore, segregation of core material from mantle should have easily occurred in the early history of the Earth.We measured electrical conductivity of (Mg_<0.93>Fe_<0.07>)SiO_3 ilmenite at pressures of 25, 35 and 40 GPa and temperature of 500 to 1000 K. We found the pre-exponential term is constant of 3×10 S/m at all of these pressures. The activation energy at 0 GPa and activation volume are 0.69±0.04 eV and -0.90±0.10 cm^3/mol. Thus pressure dependence of ilmenite is quite large.We also measured electrical conductivity of (Mg_<0.93>Fe_<0.07>)SiO_3 perovskite at pressures of 35 and 40 GPa and temperature of 500 to 1100 K. We found the pre-exponential term is constant of 1×10 S/m at both of these pressures. The activation energy at 0 GPa and activation volume are 0.39±0.02 eV and -0.06±0.04 cm^3/mol. Thus pressure dependence of pervoskite is one order of magnitude smaller than that of ilmenite.

对日本北海道日高变质带麻粒岩的电导率进行了测量。根据实验结果，我们估算了10-30 km深处高电阻区的温度为600℃。我们通过电导率测量对纯橄榄岩和二辉橄榄岩基质中的铁-铁硫化物熔体的连通性进行了估算。通过这一系列的实验，我们发现铁-硫化铁熔体的体积比大于5%时，铁-硫化铁熔体发生了连接。我们测量了（Mg_<0.93>Fe_<0.07>）SiO_3钛铁矿在25、35和40 GPa压力和500 ~ 1000 K温度下的电导率。我们发现，在所有这些压力下，指前项都是常数3×10 S/m。0 GPa下的活化能为0.69±0.04 eV，活化体积为-0.90 ~0.10 cm^3/mol。在<0.93><0.07>35和40 GPa压力和500 ~ 1100 K温度下，测量了（Mg_ Fe_）SiO_3钙钛矿的电导率。我们发现在这两种压力下，指前项都是常数1×10 ~ 5 S/m。0 GPa下的活化能为0.39±0.02 eV，活化体积为-0.06 ~0.04 cm^3/mol。因此，钙钛矿的压力依赖性比钛铁矿小一个数量级。

项目成果

Kubo, A.: "In situ X-ray observation of iron using Kawai-type apparatus equipped with Sintered diamond : absence of beta phase up to 44 Gpa and 2100 K"Geophys. Res. Lett.. (in press). (2003)

Kubo, A.：“使用配备烧结金刚石的 Kawai 型装置对铁进行原位 X 射线观察：高达 44 Gpa 和 2100 K 时不存在 β 相”Geophys。

Yoshino, T.: "Core formation triggered by grain boundary percolation"Nature. 154-157 (2003)

Yoshino, T.：“晶界渗透引发的核心形成”自然。

Kubo, A.: "In situ X-ray observation of iron using Kawai-type apparatus equipped with sintered diamond : absence of beta phase up to 44 GPa and 2100 K"Geophys.Res.Lett.. 30. 1126 (2003)

Kubo, A.：“使用配备烧结金刚石的 Kawai 型装置对铁进行原位 X 射线观察：在高达 44 GPa 和 2100 K 的压力下不存在 β 相”Geophys.Res.Lett.. 30. 1126 (2003)

Katsura, T.: "Olivine-wadsleyite transition in the system (Mg,Fe)2SiO4"J.Geophys.Res.. 109. B02209 (2004)

Katsura, T.：“系统 (Mg,Fe)2SiO4 中的橄榄石-瓦兹利石转变”J.Geophys.Res.. 109. B02209 (2004)

Katsura, T.: "Olivine-wadsleyite transition in the system (Mg, Fe)_2SiO_4"J.Geophys.Res.. 109. B02209 (2004)

Katsura, T.：“系统中的橄榄石-瓦兹利石转变 (Mg, Fe)_2SiO_4”J.Geophys.Res.. 109. B02209 (2004)