Acid-Sulfate Weathering Environment at Shergottite Provenance on Mars

Rao, M N ; Nyquist, L E ; Ross, D K ; Wentworth, S J

关键词: ACIDS;    SULFATES;    PH;    WEATHERING;    MARS ENVIRONMENT;    SHERGOTTITES;    IMPACT MELTS;    GLASS;    MINERALS;    MARS (PLANET);    WATER;    ROCKS;    RATIOS;    MINERAL DEPOSITS;   

RP-ID  :  LPI Contrib. No. 2132,JSC-E-DAA-TN65247

学科分类：天文学(综合)

美国|英语

来源: NASA Technical Reports Server

【 摘 要 】

In some impact melt (IM) glasses in the shergottites such as EET79001, Shergotty and Tissint, recently showed that secondary mineral assemblages having large sulfur excesses cannot be produced in-situ by impact shock melting of the host rock constituents. Instead, these putative secondary minerals inferred to be present in IM glasses were produced somewhere else in the shergottite source region and were subsequently mobilized into the host rock voids (by lava erosion or aolian activity) prior to impact ejection. In this abstract, we examine the aqueous conditions (pH and water/rock ratios) under which the acid sulfate solutions could have interacted with the primary minerals in the basaltic rocks and precipitated the secondary minerals such as Fe-sulfates in some cases and Ca- and Al-sulfates in other cases under favorable conditions at the shergottite provenance on Mars.