Chemical zoning in pristine objects of chondrites as archive of the thermal and redox history in the early solar nebula and planetesimals

球粒陨石原始物体的化学分区作为早期太阳星云和星子的热和氧化还原历史的档案

• 批准号: 211504527
• 负责人: Dr. Ralf Dohmen
• 金额: --
• 依托单位: Institut für Geologie, Mineralogie und Geophysik
• 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 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/211504527?language=en
• 关键词: Chemical; zoning; pristine; objects; chondrites

A number of pristine minerals have been identified in meteorites that are thought to be formed by condensation from gas in the protoplanetary accretion disk during the first few million years of the solar system. The detailed mineral chemistry and any chemical zoning preserved provide a unique archive of their thermal history. We plan to identify the various thermal events (e.g. transient heating events in the solar nebula and the thermal metamorphism on the parent body of the host meteorite) and infer the associated peak temperatures and cooling rates from the zonings of major, minor, and trace elements in these pristine minerals by means of diffusion modeling. The elaboration of the complex sequence of thermal events is now possible due to the recently published set of accurate diffusion data, recently established modeling techniques, and finally, the sensitivity of different elements in a given mineral to different temperature ranges. The latter aspect is related to the strongly different mobility of various elements within a mineral. The derived thermal histories would significantly improve our understanding of the physical conditions in the solar nebula as wells as in small planet like objects.

在陨石中发现了许多原始矿物，这些陨石被认为是在太阳系最初的几百万年里由原行星吸积盘中的气体凝结而形成的。详细的矿物化学和任何化学分区保存提供了一个独特的档案，他们的热历史。我们计划通过扩散模型确定各种热事件（例如太阳星云中的瞬态加热事件和宿主陨石母体的热变质作用），并从这些原始矿物中的主要、次要和微量元素的分带推断出相关的峰值温度和冷却速率。由于最近发表的一组精确的扩散数据，最近建立的建模技术，以及给定矿物中不同元素对不同温度范围的敏感性，现在有可能详细说明复杂的热事件序列。后一个方面与矿物中各种元素的强烈不同的流动性有关。导出的热历史将显著提高我们对太阳星云以及类似小行星的物体的物理条件的理解。