Hydrous alteration of olivine macrocrysts in a Martian olivine phyric basalt, NWA 10416, and a terrestrial basalt from southern Colorado are examined using SEM, EPMA, TEM, and µXRD techniques. The olivines in the meteorite contain linear nanotubes of hydrous material, amorphous areas, and fluid dissolution textures quite distinct from alteration identified in other Martian meteorites. Instead, they bear resemblance to terrestrial deuteric alteration features. The presence of the hydrous alteration phase Mg‐laihunite within the olivines has been confirmed by µXRD analysis. The cores of the olivines in both Martian and terrestrial samples are overgrown by unaltered rims whose compositions match those of a separate population of groundmass olivines, suggesting that the core olivines are xenocrysts whose alteration preceded crystallization of the groundmass. The terrestrial sample is linked to deep crustal metasomatism and the “ignimbrite flare‐up” of the Oligocene epoch. The comparison of the two samples suggests the existence of an analogous relatively water‐rich magmatic reservoir on Mars.

中文翻译：

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火星和地球上的含水橄榄石蚀变

使用SEM，EPMA，TEM和µXRD技术检查了火星橄榄石天然玄武岩NWA 10416和来自科罗拉多州南部的陆地玄武岩中橄榄石大晶的含水量变化。陨石中的橄榄石包含线性的纳米管，其具有含水材料，无定形区域和流体溶解质地，这与其他火星陨石中发现的蚀变完全不同。相反，它们与陆地氘代改变特征相似。µXRD分析证实橄榄石中存在水合蚀变相Mg-镧红石。火星和陆地样品中橄榄石的核心都被未变质的轮辋长满，其组成与单独的地面质量橄榄石种群相同。这说明核心橄榄石是异晶，其变化先于地层结晶。陆地样品与深层地壳交代作用和渐新世时代的“火成岩爆发”有关。两种样品的比较表明，火星上存在着一个类似的相对富水的岩浆储层。