High water solubility of ringwoodite at mantle transition zone temperature
High water solubility of ringwoodite at mantle transition zone temperature
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DOI：
10.1016/j.epsl.2019.115987
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发表时间：
2020-02-01
影响因子：
5.3
通讯作者：
Katsura, Tomoo
中科院分区：
文献类型：
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作者：
Fei, Hongzhan;Katsura, Tomoo
地幔过渡带是地球内部的一个潜在的水储库，建议其含有大于1 wt.%的水。H2O，至少在局部，通过天然的富含水的ringwoodite夹杂物（Pearson等人，2014）和矿物粘度（Fei等人，2017年）。这与林伍德石的低水溶解度（<0.3wt.%）相反。在基于实验室实验的地幔过渡区温度下（Ohtani等人，2000年）。我们重新研究了1600-2000 K时水在灵伍德石中的溶解度，结果表明，无铁和含铁的灵伍德石都可以储存约0.8-1.2 wt.%的水。H2O在地幔过渡带的条件下。温度对含铁体系中H2O溶解度的影响较小，而对无铁体系中H2O溶解度的影响较大。林伍德石的高水溶解度与富水地幔过渡带是相容的。先前报告的相对较低的值可能是由于H2O源不足或未被SiO2缓冲。(C)2019爱思唯尔B. V.保留所有权利。
The mantle transition zone, a potential water reservoir in the Earth's interior, is suggested to contain more than 1 wt.% of H2O, at least locally, by the natural water-rich ringwoodite inclusion (Pearson et al., 2014) and the mineral viscosity (Fei et al., 2017). It is against the low H2O solubility of ringwoodite (< 0.3 wt.%) at mantle transition zone temperature based on laboratory experiments (Ohtani et al., 2000). We revisited the H2O solubility in ringwoodite at 1600-2000 K, showing that both iron-free and iron-bearing ringwoodite can store about 0.8-1.2 wt.% of H2O under mantle transition zone conditions. Temperature has a relatively small effect on the H2O solubility in iron-bearing system, but much larger in iron-free one. The high H2O solubility of ringwoodite is compatible with the water-rich mantle transition zone. The relatively low values reported previously is probably due to insufficient H2O source or unbuffered by SiO2. (C) 2019 Elsevier B.V. All rights reserved.