Tridymite in a lacustrine mudstone in Gale Crater, Mars: Evidence for an explosive silicic eruption during the Hesperian
Tridymite in a lacustrine mudstone in Gale Crater, Mars: Evidence for an explosive silicic eruption during the Hesperian
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火星盖尔陨石坑湖相泥岩中的鳞石英：西方纪时期硅质爆发性喷发的证据
DOI：
10.1016/j.epsl.2022.117694
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发表时间：
2022
影响因子：
5.3
通讯作者：
Rampe, E.B.
中科院分区：
文献类型：
--
作者：
Payré, V.;Siebach, K.L.;Thorpe, M.T.;Antoshechkina, P.;Rampe, E.B.
意外地检测到16wt.%火星盖尔陨石坑中原本是湖相泥岩的单斜鳞石英（一种高温二氧化硅多晶型物）引发了有关其形成和该行星岩浆演化程度的重大问题。由好奇号探测器上的X射线衍射仪分析的岩石样品也含有长石、方石英和乳白色二氧化硅（± Si玻璃）。单斜鳞石英在地球上极为罕见，只在火山环境、高温撞击环境和地外岩石中发现过。本文综述了天然鳞石英最常见的形成途径，并通过模拟实验探讨了可能的形成机制。我们考虑了样品的更广泛背景，提出了一种形成和运输机制，其基础是：（1）泥岩和附近岩石的矿物组合，（2）泥岩层的组成，以及（3）整体地质背景。基于大量的鳞石英，高SiO2和低Al2O3浓度的泥岩，和低温环境内远湖泥岩，我们建议，爆炸喷发释放富硅灰，这是沉积到盖尔火山口的分水岭作为富鳞石英灰沿着方石英，长石，氧化钛，富硅玻璃，当盖尔还是一个湖（西方）。在搬运过程中，富硅玻璃的溶解和矿物分选会使鳞石英富集，产生乳白色硅沉淀，并使Al2O3浓度相对降低。这种情况意味着火星上的爆发性火山活动发生在西方，可能不限于玄武岩喷发，揭示了火星岩浆活动的复杂性。
The unexpected detection of ∼16 wt.% monoclinic tridymite, a high-temperature silica polymorph, within an otherwise lacustrine mudstone in Gale crater, Mars raises significant questions about its formation and the extent of magmatic evolution on that planet. The rock sample, analyzed by the X-ray diffractometer onboard theCuriosityrover, also contained feldspar, cristobalite, and opaline silica (±Si-glass). Monoclinic tridymite is extremely rare on Earth, and has only been discovered in silicic volcanic environments, high-temperature impact settings, and extraterrestrial rocks. We review the most common formation pathways of natural tridymite and run thermodynamical models to investigate possible formation mechanisms. We consider the broader context of the sample to propose a formation and transport mechanism based on: (1) the mineralogical assemblage of the mudstone and rocks in the vicinity, (2) the composition of the mudstone layer, and (3) the overall geological context. Based on the large amount of tridymite, the high SiO2and low Al2O3concentration of the mudstone, and the low temperature context within distal lacustrine mudstone, we propose that an explosive eruption released Si-rich ashes, which were deposited into Gale crater's watershed as a tridymite-rich ashfall along with cristobalite, feldspar, Ti-oxide, and Si-rich glass, when Gale was still a lake (Hesperian). The dissolution of Si-rich glass and mineral sorting during transport would have concentrated tridymite, caused opaline silica precipitation, and relatively lowered the Al2O3concentration. This scenario implies that explosive volcanism on Mars occurred during the Hesperian and might not be restricted to basaltic eruptions, revealing the complexity of Mars magmatism.
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影响因子：
2.7
作者：
H. Schneider;K. Wohlleben;A. Majdič
通讯作者：
A. Majdič
月球鳞石英和方英石
DOI：
--
发表时间：
1972
期刊：
影响因子：
--
作者：
Bhian Mason
通讯作者：
Bhian Mason
大气压力对火星火山碎屑扩散的影响
DOI：
--
发表时间：
2013
期刊：
影响因子：
--
作者：
L. Kerber;F. Forget;J. Madeleine;R. Wordsworth;J. Head;L. Wilson
通讯作者：
L. Wilson
Twiggs 粘土中具有鳞石英结构的无序二氧化硅
DOI：
--
发表时间：
2008
期刊：
影响因子：
--
作者：
Lori G. Eversull;R. Ferrell
通讯作者：
R. Ferrell
鳞石英在熔结岩冷却和气相变化过程中分布的意义
影响因子：
3.1
作者：
Yuli Heled;M. C. Rowe;I. Chambefort;C. Wilson
通讯作者：
C. Wilson