Biogenic Carbon in Magmatic Minerals and Implications for the Preservation and Obliteration of Hadean Isotopic Biosignatures

岩浆矿物中的生物碳及其对冥宙同位素生物特征保存和湮灭的影响

• 批准号: 404682212
• 负责人: Professor Dr. Axel Karl Schmitt, Ph.D.
• 金额: --
• 依托单位: Institut für Geowissenschaften
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/404682212?language=en
• 关键词: Biogenic; Carbon; Magmatic; Minerals; Implications

The preservation of geologic materials from the early period when Earth became a habitable planet is precarious. Only rare examples of detrital zircon crystals have escaped obliteration since the Hadean eon. These crystals also host a rich inclusion assembly which attests to their formation conditions. The presence of light carbon isotopic compositions of graphite inclusions in Hadean zircon has been interpreted to indicate an early emergence of terrestrial life. We aim to follow up on this discovery by investigating graphite inclusions in minerals from post-Hadean granites by (1) devising criteria which can aid in identifying post entrapment disturbance of inclusions, and (2) constraining how graphite in igneous rocks relates to biogenic carbonaceous materials, and how these materials contribute to magmatic carbon budgets. The proposed research will, for the first time, use correlated micro-analytical imaging and high spatial resolution mass-spectrometry techniques to resolve the origins of graphite in magmatic rocks, especially as inclusions. Insights gained from two S-type granite locations in northeastern North America and Central Europe will improve the interpretation of Hadean graphite inclusions in zircon. The methodologies we plan to develop will be implemented in a collaborative search for additional carbonaceous inclusions from the Hadean by an international research consortium, which currently has succeeded in identifying the largest number of Hadean zircon crystals worldwide.

从地球成为一个可居住的星球的早期地质材料的保存是不稳定的。自冥古宙以来，只有极少数的碎屑锆石晶体逃过了湮灭。这些晶体还拥有丰富的内含物组件，这证明了它们的形成条件。在冥古宙锆石中石墨包裹体的轻碳同位素组成的存在被解释为指示早期的陆地生命的出现。我们的目标是跟进这一发现，通过调查矿物石墨包裹体从后Hadean花岗岩（1）设计标准，可以帮助识别包裹体的后圈闭干扰，（2）约束石墨在火成岩中如何与生物碳质材料，以及这些材料如何有助于岩浆碳收支。拟议的研究将首次使用相关的微观分析成像和高空间分辨率质谱技术来解决岩浆岩中石墨的起源，特别是作为包裹体。从北美东北部和中欧的两个S型花岗岩地点获得的见解将改善锆石中冥古宙石墨包裹体的解释。我们计划开发的方法将在一个国际研究财团的合作搜索中实施，该财团目前已成功地确定了全球最大数量的冥古宙锆石晶体。