Activity of aqueous fluids in the early solar system - characterization and formation timescales of the earliest water-bearing phases in chondritic samples

早期太阳系中水性流体的活动 - 球粒陨石样品中最早含水相的特征和形成时间尺度

• 批准号: 211767861
• 负责人: Professor Dr. Addi Bischoff
• 金额: --
• 依托单位: Institut für Geologische Wissenschaften
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2012
• 资助国家: 德国
• 起止时间: 2011-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/211767861?language=en
• 关键词: Activity; aqueous; fluids; early; solar

This project aims to unravel the origins and formation timescales of one of the least understood components in primitive solar system samples: hydrous minerals like tochilinite and cronstedtite that have reacted with a nebular and/or parent body water reservoir and related phases like carbonates. Since decades a fundamental controversy in meteorite research is heavily discussed: Does all aqueous alteration observed in chondrites is the result of a reaction with liquid water (in-situ) on the meteorite parent body after final accretion or has at least an important fraction of these minerals reacted with water before incorporation into the final parent body (pre-accretionary alteration)? It will therefore be essential to distinguish a pre-accretionary from an asteroidal-only formation environment by means of structural and isotopic analyses. The fundamental importance of this project is to study different isotope systems (O- and D/H-isotopes including Mn-Cr-isotopes for carbonates) and mineralogical details on the same grains in order to distinguish between different reservoirs of aqueous activity and to define different formation timescales of hydrous phases and carbonates. The techniques in this proposal are exclusively in-situ and will combine the isotopic analysis of individual phases by secondary ion mass spectrometry (SIMS) with structure determinations by high resolution transmission electron microscopy (TEM).

该项目旨在揭示原始太阳系样本中最不了解的成分之一的起源和形成时间尺度：与星云和/或母体水储层以及碳酸盐等相关相反应的含水矿物，如tochilinite和cronstedtite。几十年来，陨石研究中的一个基本争议被大量讨论：是否所有在陨石中观察到的含水蚀变都是最终吸积后与陨石母体上的液态水（原位）反应的结果，或者至少有一部分这些矿物在并入最终母体之前与水反应（预吸积蚀变）？因此，通过结构和同位素分析区分预增生形成环境和仅小行星形成环境至关重要。该项目的根本重要性是研究不同的同位素系统（O-和D/H-同位素，包括碳酸盐的Mn-Cr-同位素）和相同颗粒的矿物学细节，以区分不同的含水活性储层，并确定含水相和碳酸盐的不同形成时间尺度。该提案中的技术完全是原位的，并将联合收割机通过二次离子质谱法（西姆斯）对各相进行同位素分析，并通过高分辨率透射电子显微镜（TEM）进行结构测定。