Shock-induced melting of MgSiO3 perovskite and implications for melts in Earth's lowermost mantle -: art. no. L14612
Shock-induced melting of MgSiO3 perovskite and implications for melts in Earth's lowermost mantle -: art. no. L14612
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DOI：
10.1029/2004gl020237
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发表时间：
2004-07-30
影响因子：
5.2
通讯作者：
Ahrens, TJ
中科院分区：
文献类型：
--
作者：
Akins, JA;Luo, SN;Ahrens, TJ
顽辉石和 MgSiO3 玻璃的新冲击波状态方程 (EOS) 数据将镁硅酸盐钙钛矿熔化时的密度变化限制在高达 200 GPa。在地球下地幔底部附近，熔体变得比钙钛矿密度更大。这一推论得到了冲击温度数据的证实，表明高压下熔化曲线上存在负压力-温度斜率。尽管地幔熔化涉及多个阶段和化学成分，但这意味着用于解释最下地幔异常地震速度的部分熔化可能是动态稳定的。
New shock wave equation of state (EOS) data for enstatite and MgSiO3 glass constrain the density change upon melting of Mg-silicate perovskite up to 200 GPa. The melt becomes denser than perovskite near the base of Earth's lower mantle. This inference is confirmed by shock temperature data suggesting a negative pressure-temperature slope along the melting curve at high pressure. Although melting of Earth's mantle involves multiple phases and chemical components, this implies that the partial melts invoked to explain anomalous seismic velocities in the lowermost mantle may be dynamically stable.