A multiple isotope and trace element approach to constrain the oxygenation and metal cycling of 3.5 to 3.2 Ga paleo-oceans

限制 3.5 至 3.2 Ga 古海洋氧化和金属循环的多同位素和微量元素方法

• 批准号: 204399623
• 负责人: Professor Dr. Gerhard Peter Brey, Ph.D.
• 金额: --
• 依托单位: Abteilung Petrologie und Geochemie
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/204399623?language=en
• 关键词: multiple; isotope; trace; element; approach; multiple; isotope; trace; element; approach

Geochemical proxies for the oxygenation of and metal cycling in the hydrosphere, such as Mo, U, Re-Os, S and Fe isotopes can be used to establish the spatiotemporal distribution of these elements in Paleo-oceans, which is inextricably linked to the evolution of life on Earth, by using well-dated and well-preserved marine sediments. However, to date, only little appropriate material is available especially for the Archaean. The Paleo- to Meso-Archaean Barberton Greenstone Belt, South Africa, represents the rosetta stone of research into the earliest Earth processes and conditions because it consists of little metamorphosed volcano-sedimentary successions. However, the primary (bio)geochemical signatures, especially of redox-sensitive elements, of outcrop samples may be compromised. Therefore, it is imperative to obtain continuous sections of unaltered, fresh material through drilling. Using drill core material from the Barberton Drilling Project, we seek funding to constrain (1) the metal sources, redox conditions and potential participation of biota in the Paleo-ocean, using Re-Os-Fe isotopes and platinum-group element systematics of organic-rich stratigraphic layers, banded iron formations and cherts deposited in the shallow to deep marine environment and (2) PGE and Os isotope composition of felsic volcanic rocks, which represent the continental sources of erosion products subsequently deposited on the ocean floor. Application of state-of-the-art geochemical tools to prospective sample material, strategic collaborations with other institutes and integration of data using multiple proxies offer a promising approach to successfully address these questions.

在水圈中氧合和金属循环的地球化学代理，例如Mo，U，Re-OS，S和Fe同位素，可用于建立这些元素在古生物中的时空分布，该元素通过使用良好的和良好的Marine Sitements和良好的Marine Sitements与地球上的生命进化无关。但是，迄今为止，特别是对于古细菌而言，只有很少的合适材料可用。南非的古河畔河畔巴伯顿绿石带代表了对最早的地球过程和条件的研究石材，因为它由几乎没有变形的火山辅助继承。但是，可能会损害主要（生物）地球化学特征，特别是对氧化还原敏感元素的露头样品。因此，必须通过钻孔获得不变的新鲜材料的连续部分。使用Barberton钻探项目中的钻头核心材料，我们寻求资金来限制（1）使用Re-OS-FE同位素以及富含有机富含有机物的富含有机物层层的铂类同位素系统的金属来源，氧化还原条件和生物群的潜在参与。火山岩代表了随后沉积在海底的侵蚀产物的大陆源。将最先进的地球化学工具应用于预期样本材料，与其他机构的战略合作以及使用多个代理集成数据的战略合作，为成功解决这些问题提供了一种有希望的方法。