ワズレライトとリングウッドライトの電気伝導性からの移行地帯の水分含有量

Xiaoge Huang¹, Yousheng Xu, Shun-Ichiro Karato

¹Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China.

Nature

|April 9, 2005

まとめ

地球地球地球地球地球

科学分野:

地質物理学地質物理学とは地質物理学です.
ミネラル物理学ミネラル物理学
地質化学地質化学

背景:

地球の移行地帯 (410660 km深さ) は,鉱水溶解性のために重要な水貯蔵庫として機能する可能性があります.
水の含有量は地球の進化と物質の性質に影響を与えます.
移行地帯の正確な水量は不明である.

研究の目的:

水と気温がワドスライトとリングウッドイトの電気伝導性に与える影響を測定する.
マントルの移行地帯の水分量を推測する.

主な方法:

異なる水と温度条件下でのワドスライトとリングウッドイットの電気伝導性の実験的決定.
実験結果と地球物理学的伝導率データとの比較.

主要な成果:

ワドスライトとリングウッドイットの電気伝導性は,水分に非常に敏感ですが,温度にはそれほど敏感ではありません.
太平洋マントルの移行地帯における推論された水の含有量は,約0.10.2 wt%の質量である.
この推論された水分量は,上層マントルの部分的な融解の臨界値を超えています.

結論:

マントルの移行地帯の水分量は地域によって異なる.
太平洋などの地域では,およそ410kmの深さで部分的に溶ける可能性があり,元素の分布に影響を与えます.
これらの鉱物の電気伝導性を制御する主な要因は温度ではなく,水分である.

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