Quantitative study of textures and micro- structures of olivine- rich achondrites as indication for cumulate formation and early solid-state deformation in asteroids.

富含橄榄石的无球粒陨石的纹理和微观结构的定量研究，作为小行星累积形成和早期固态变形的指示。

• 批准号: 320205871
• 负责人: Professor Dr. Frank Erich Brenker
• 金额: --
• 依托单位: Abteilung Petrologie und Geochemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/320205871?language=en
• 关键词: Quantitative; study; textures; micro; structures

Based on our unpredicted finding of solid state plastic deformation during our work on diogenites (Tkalcec et al. 2013), which will have several far reaching consequences on the thermal history, chemical and structural equilibration in the early stages of asteroid and protoplanet formation, we propose to perform a comprehensive quantitative structural and textural study of a sub-type of unbreciated, ureilites showing a well defined crystal lattice orientation.A characterization and quantification of the micro and nano structural inventory of this rock type will be performed. This enables to unravel details of the thermal and structural evolution and the effective deformation mechanism. A combination of electron backscatter diffraction (EBSD) and large area transmission electron microscopic (TEM) will be applied in order to measure details of the crystallographic preferred orientation and relate them to texture forming processes like crystallization, compaction, shock effects and deformation mechanism. These processes are essential for the understanding of planetary differentiation, mantle mingling or mixing and initial cooling of asteroids and planetary embryos.Ureilites are ideal candidates for this attempt as they represent the second most common type of achondrites, resemble olivine-rich mantle rocks and the fast cooling from their initial conditions preserve most of the original fabric and microstructure.

基于我们在借助锂矿的工作期间对固态塑性变形的发现（Tkalcec等，2013），这将对小行星和Protoplanet形成的早期阶段的热历史，化学历史，化学和结构平衡产生几种影响，我们建议在综合的定量结构和质地上进行一项综合的结构和质地研究。晶格方向。将对这种岩石类型的微观和纳米结构清单进行表征和定量。这使得能够揭开热和结构演化的细节以及有效的变形机制。将使用电子反向散射衍射（EBSD）和大面积传输电子显微镜（TEM）的组合，以衡量晶体学首选方向的细节，并将它们与形成纹理形成质地形成诸如结晶，压实，休克，休克效应和变形机制等纹理相关联。这些过程对于理解行星差异，地幔混合或混合以及小行星和行星胚胎的初始冷却至关重要。UREILITES是这种尝试的理想候选者，因为它们代表了第二种最常见的金属盐类型，这是含有橄榄岩的第二大类型，是橄榄型富含橄榄石富含橄榄石的岩石岩石，以及从最初的条件中快速冷却原始结构和原始结构。