Fate of subducted argon in the deep mantle
Fate of subducted argon in the deep mantle
复制标题
俯冲氩在地幔深处的命运
DOI：
10.1038/s41598-020-58252-8
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发表时间：
2020
影响因子：
4.6
通讯作者：
Shigeaki Ono
中科院分区：
文献类型：
--
作者：
Kai;K.;Y. Nishio;K. Kawai;T. Maki;J. Noda;B. Hoshino; N. Sugimoto ; E. Munkhjargal;D. Jugder;D. Batdorj;志賀正崇，小長井一男，池田隆明;Shigeaki Ono
采用金刚石压砧实验和第一性原理分子动力学方法研究了氩气在382 GPa和3000 K下的物理性质。Ar的密度估计值小于PREM地幔的密度，表明下地幔底部没有发生密度交叉。在高于200 GPa的压力下，Ar的热压力显示出很大的体积依赖性，并且在高压下确认了计算出的有效Grüneisen参数的显着温度依赖性。Ar的熔化温度估计从计算数据和一个显着的压力依赖性被确认。如果俯冲板片的压力-温度路径低于临界条件（~750 K和~7.5 GPa），则固态Ar可被向下携带到地幔深部。上涌地幔柱中固态Ar的熔融发生在过渡带底部。因此，固体Ar在地球内部Ar循环中起着重要作用。
The physical properties of argon (Ar) are investigated to 382 GPa and 3000 K using diamond anvil cell experiments and first-principles molecular dynamics. The estimated density of Ar is smaller that of the Preliminary reference Earth model (PREM) mantle, which indicates that the density crossover does not occur at the bottom of the lower mantle. A large volume dependence of the thermal pressure of Ar is revealed at pressures higher than 200 GPa, and a significant temperature dependence of the calculated effective Grüneisen parameters is confirmed at high pressures. A melting temperature of Ar is estimated from the calculation data and a significant pressure dependence is confirmed. If the pressure-temperature path of the subducted slab is lower than the critical condition, ~750 K and ~7.5 GPa, solid Ar can be carried down into the deep mantle. Melting of solid Ar in the upwelling mantle plume occurs at the bottom of the transition zone. Thus, solid Ar plays an important role in Ar recycling in the Earth’s interior.