Water storage capacity of the martian mantle through time
Water storage capacity of the martian mantle through time
复制标题
火星地幔随时间变化的储水能力
DOI：
10.1016/j.icarus.2022.115113
复制
发表时间：
2022
期刊：
影响因子：
3.2
通讯作者：
Brennan, Matthew C.
中科院分区：
文献类型：
--
作者：
Dong, Junjie;Fischer, Rebecca A.;Stixrude, Lars P.;Lithgow-Bertelloni, Carolina R.;Eriksen, Zachary T.;Brennan, Matthew C.
自火星地幔形成以来，水就一直储存在地幔中，主要以名义上的无水矿物形式存在。火星表面短暂的早期水圈和间歇性流动的水可能是由地幔的岩浆脱气提供和补充的。估计火星固体地幔的储水量对其水库存有重要的限制，并有助于阐明火星上水的来源、汇和时间变化。本研究基于文献收集的高压实验数据，采用自举聚集法研究了铁元素对橄榄石、瓦德利石和环伍德石储水能力的影响，并定量估计了富feo火星固体地幔储水能力的上限。在不同的地幔势温（Tp）下，我们估计现今火星地幔（atTp= 1600 K）的储水量为9.0−2.2+2.8km，初始火星地幔（atTp= 1900 K）为4.9−1.5+1.7km。随着时间的推移，火星地幔的储水能力随着时间的推移而增加，但由于火星上缺乏有效的水循环机制，其实际的地幔含水量可能大大低于今天的储水能力。
Water has been stored in the Martian mantle since its formation, primarily in nominally anhydrous minerals. The short-lived early hydrosphere and intermittently flowing water on the Martian surface may have been supplied and replenished by magmatic degassing of water from the mantle. Estimating the water storage capacity of the solid Martian mantle places important constraints on its water inventory and helps elucidate the sources, sinks, and temporal variations of water on Mars. In this study, we applied a bootstrap aggregation method to investigate the effects of iron on water storage capacities in olivine, wadsleyite, and ringwoodite, based on high-pressure experimental data compiled from the literature, and we provided a quantitative estimate of the upper bound of the bulk water storage capacity in the FeO-rich solid Martian mantle. Along a series of areotherms at different mantle potential temperatures (Tp), we estimated a water storage capacity equal to 9.0−2.2+2.8km Global Equivalent Layer (GEL) for the present-day Martian mantle atTp= 1600 K and 4.9−1.5+1.7km GEL for the initial Martian mantle atTp= 1900 K. The water storage capacity of the Martian mantle increases with secular cooling through time, but due to the lack of an efficient water recycling mechanism on Mars, its actual mantle water content may be significantly lower than its water storage capacity today.