Changes in weathering, elemental cycling, bioproductivity and redox-conditions of shallow to deep marine environments during the Great Oxidation Episode

大氧化期间浅层到深层海洋环境的风化、元素循环、生物生产力和氧化还原条件的变化

• 批准号: 543675433
• 负责人: Professor Dr. Ronny Schönberg, Ph.D.
• 金额: --
• 依托单位: School of Earth and Environmental Sciences
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/543675433?language=en
• 关键词: Changes; weathering; elemental; cycling; bioproductivity

This project seeks to investigate feedback loops between modes and changes in continental weathering, elemental cycling from source to sink, bioproductivity and redox conditions of shallow to deep marine environments in response to the atmospheric oxygen build-up during the Great Oxidation Episode (GOE). The Pretoria Group of the Transvaal Basin in South Africa is an ideal archive for this study with an almost continuous sedimentary record of the GOE from the 2.32 Ga Timeball Hill Formation – which recently revealed repeated short-term cycling between slightly oxidized and reducing atmospheric conditions via changes between mass-dependent and mass independent fractionation of S isotopes (MDF-S and MIF-S, respectively) – up to the c. 2.08 Ga Magaliesberg Formation – which was deposited during the positive δ13Ccarb excursion of the Lomagundi Event, which has previously been interpreted as a time of oxygen overshoot to near-present O2 levels. Geochemical tools that will be used to retrieve this information are major- and trace element systematics combined with TOC, TN, TS and δ13Corg, δ13Ccarb as well as Fe-Mo-W stable isotope measurements. The project is planned for the duration of 36 months.

该项目旨在研究大陆风化模式和变化之间的反馈回路，从源到汇的元素循环，生物生产力和浅到深海洋环境的氧化还原条件，以应对大氧化事件（GOE）期间大气中的氧气积累。南非德兰士瓦盆地的比勒陀利亚群是这项研究的理想档案，它几乎连续记录了2.32 Ga Timeball Hill地层的GOE-最近揭示了通过S同位素的质量依赖和质量无关分馏之间的变化，在轻微氧化和还原大气条件之间重复的短期循环（MDF-S和MIF-S，分别）-高达c。2.08 Ga Magaliesberg地层-在Lomagundi事件的正δ 13 Ccarb偏移期间沉积，该事件先前被解释为氧气超负荷至接近当前O2水平的时间。地球化学工具，将用于检索这一信息的主要和微量元素系统结合TOC，TN，TS和δ 13 Corg，δ 13 Ccarb以及Fe-Mo-W稳定同位素测量。该项目计划为期36个月。