Constraining the interplay of geodynamics with the biosphere and atmosphere across the Archean-Proterozoic boundary

这项研究旨在追踪太古代-元古界全球地球动力学的变化，以表征构造与生物圈和大气演化之间的潜在联系。 地球今天的地表环境是45亿年变化的产物，反映了全球范围的地质、大气和生物过程。这种长期的进化不时被一些标志性事件打断，这些事件永久地和不可逆转地改变了世界各地的化学和生物系统。特别是，从太古宙到元古界的过渡(25亿年前)被许多人认为是地球历史上最重要的时期。此时的地质变化意味着地球动力学的重大变化，这反过来可能影响了生物进化和大气氧合。 最近的大量研究表明，地质记录从~25亿年前到~21亿年前发生了重大变化，包括火成岩和沉积岩、锆石和大气成分的变化。太古代-元古界过渡的特点还包括保存的地质记录暂停，陆壳迅速上升到海平面以上，以及最早的低纬冰期。 这一建议的短期目标是：(1)提供与太古代-元古代过渡有关的沉积岩和火成岩中氧和硫同位素特征位移的高分辨率时间约束；(2)评估25-21亿年前地质间歇期间离散地质区的地球动力学，以及造山、大陆高于海平面上升和沉积物质向地球深处转移之间的关系。 该项目的同位素研究将在加拿大领先的地球化学设施中使用尖端的微观分析技术，包括艾伯塔大学的大几何离子探测器设施以及女王大学的分析设施。目前的研究计划将支持8个HQP(2个博士，2个硕士，4个理科)的研究。学生将接受野外地质学、实验室和分析方法方面的教育，以及向科学界和公众解释和交流科学数据的过程。 这一研究计划的长期目标是提供地幔长期变化与地壳深处火成岩之间的联系，地幔的长期变化深刻地影响了生物圈和大气的演化，导致沉积物成分的变化。这项研究计划的重要性在于展示了地球深处与生物圈和大气相互交织的过程。这项研究产生的新的可测试框架将为未来许多年的继续科学探索提供途径。

This study aims to track changes in global geodynamics across the ArcheanProterozoic boundary to characterize the potential link between tectonics and the evolution of the biosphere and atmosphere. Earth's present-day surface environments are the product of 4.5 billion years of change that reflects global-scale geologic, atmospheric, and biologic processes. This secular evolution is punctuated with a handful of hallmark events that permanently and irreversibly altered chemical and biological systems worldwide. In particular, the transition from the Archean to Proterozoic Eons (2.5 billion years ago) is considered by many to have been the most significant period of time in Earth history. The geologic changes at this time carry implications for significant shifts in geodynamics which in turn may have influenced biologic evolution and atmospheric oxygenation. Numerous recent studies have demonstrated significant shifts in the geologic record from ~2.5 to ~2.1 billion years ago, including changes in the composition of igneous and sedimentary rocks, zircon, and atmosphere. The ArcheanProterozoic transition is also characterized by a lull in the preserved geologic record, rapid rise of continental crust above sea level, and the earliest episode of low-latitude glaciation. The short-term goals of this proposal are (1) to provide high resolution temporal constraints on shifts of oxygen and sulfur isotopic signatures in sedimentary and igneous rocks associated with ArcheanProterozoic transition and (2) to evaluate the geodynamics of discrete geologic regions during the geologic lull of 2.5-2.1 billion years ago, and the relationship between mountain building, rise of continents above sea-level, and the transfer of sedimentary material into the deep Earth. The isotopic research of this project will use cutting-edge micro-analytical techniques at leading geochemical facilities in Canada including the large-geometry ion probe facility at the University of Alberta as well as the analytical facilities at Queen's University. The current research program will support the research of eight HQPs (2 PhD, 2 MSc, 4 BSc). Students will receive an education in field geology, laboratory and analytical methods, and the process of interpreting and communicating scientific data to the scientific community and general public. The long-term goal of this research program is to provide a link between secular changes in the mantle that profoundly influenced the evolution of the biosphere and atmosphere that led to changes in the composition of sediment and the igneous rocks derived from deep in Earth's crust. The importance of this research program is a demonstration of the intertwined processes of the deep Earth with the biosphere and atmosphere. The new testable framework resulting from this research will provide avenues of continued science inquiry for many years to come.