Evolution of water reservoirs on Mars: Constraints from hydrogen isotopes in martian meteorites
Evolution of water reservoirs on Mars: Constraints from hydrogen isotopes in martian meteorites
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DOI：
10.1016/j.epsl.2014.03.027
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发表时间：
2014-03
影响因子：
5.3
通讯作者：
H. Kurokawa;Masahiko Sato;M. Ushioda;T. Matsuyama;R. Moriwaki;J. Dohm;T. Usui
中科院分区：
文献类型：
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作者：
H. Kurokawa;Masahiko Sato;M. Ushioda;T. Matsuyama;R. Moriwaki;J. Dohm;T. Usui
火星表面的形态表明，火星曾经足够温暖，可以在其表面保持持久的液态水。虽然目前火星大气的高D/H比(∼是地球海水的6倍)表明，在火星历史上，地表已经失去了大量的水，但水损失的时间、过程和数量一直没有得到很好的约束。最近对火星陨石进行离子探针分析的技术进展，为准确估计陨石形成时火星水库的氢同位素组成(D/H)提供了准确的估计。基于陨石的D/H数据，这项研究表明，前诺亚纪期(>；41-99m全球当量层，凝胶)的水分损失比火星历史的其他时期(>；10-53m 凝胶)更显著。结合我们的结果和古海洋的地质地貌证据，我们认为火星上应该存在未探测到的地下水/冰(≃100-1000m 凝胶)，并且超过了火星上可见的现今水储量(≃20-30m 凝胶)。
Martian surface morphology implies that Mars was once warm enough to maintain persistent liquid water on its surface. While the high D/H ratios (∼6 times the Earth's ocean water) of the current martian atmosphere suggest that significant water has been lost from the surface during martian history, the timing, processes, and the amount of the water loss have been poorly constrained. Recent technical developments of ion-microprobe analysis of martian meteorites have provided accurate estimation of hydrogen isotope compositions (D/H) of martian water reservoirs at the time when the meteorites formed. Based on the D/H data from the meteorites, this study demonstrates that the water loss during the pre-Noachian (>41–99 m global equivalent layers, GEL) was more significant than in the rest of martian history (>10–53 m GEL). Combining our results with geological and geomorphological evidence for ancient oceans, we propose that undetected subsurface water/ice (≃100–1000 m GEL) should exist, and it exceeds the observable present water inventory (≃20–30 m GEL) on Mars.