CAREER: Understanding how Earth's coupled carbon and sulfur cycles evolved after the oxygenation of the atmosphere

职业：了解大气氧化后地球的碳硫循环耦合如何演化 负责人：Clara Blättler（芝加哥大学）这项研究将提高对大约 23 亿年前大气中出现氧气后地球作为行星演化的理解。该项目将重点关注这一时期沉积的一组独特岩石，并由国际合作组织于 2007 年收集。通过研究这些岩石中碳循环和硫循环的沉积记录，这项研究将展示向含氧大气的过渡如何影响地球相互关联的地球化学循环。作为这些研究活动的补充，我们将通过与菲尔德自然历史博物馆的合作，在 K-12 教育和公共环境中宣传地球及其古代环境的历史。将开发一个实践工具包，通过精选的岩石标本、活动和在线内容介绍这些科学思想，该资源将在菲尔德博物馆、教师专业发展研讨会以及芝加哥的当地外展活动中展示。该项目将测试有关古元古代大氧化事件和洛马贡迪-贾图利事件的规模和解释的假设。由于碳酸盐地球化学记录的固有局限性，在此氧化还原转变期间有机碳埋藏量和海水硫酸盐储层的大小是不确定的。通过多代理地球化学方法来测试成岩作用、自生矿物和当地人工制品，将为 Fennoscandia 的古元古代记录生成更可靠的全球碳酸盐碳同位素比和硫同位素比重建。这些结果将用于生成修正后的全球生物地球化学模型，用于古元古代表面氧化还原和氧气产生的演化。为了帮助教授有关地球氧化还原演化的知识，我们将开发动手体验箱，这些箱将在菲尔德博物馆的哈里斯学习收藏中流通，并由从事这项研究的科学家在几次外展活动中使用。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

CAREER: Understanding how Earth's coupled carbon and sulfur cycles evolved after the oxygenation of the atmospherePI: Clara Blättler (University of Chicago)This research will improve understanding of Earth’s evolution as a planet following the appearance of oxygen in the atmosphere approximately 2.3 billion years ago. The project will focus on a unique set of rocks deposited during this period of time and collected by an international collaboration in 2007. By studying the sedimentary record of the carbon cycle and sulfur cycle in these rocks, this research will show how the transition to an oxygenated atmosphere impacted Earth’s interconnected geochemical cycles. Complementing these research activities, the history of Earth and its ancient environments will be promoted in K–12 education and public settings through a collaboration with the Field Museum of Natural History. A hands-on kit will be developed to introduce these scientific ideas through select rock specimens, activities, and online content, and this resource will be showcased at the Field Museum, professional development workshops for teachers, and local outreach events in Chicago.The project will test hypotheses about the magnitude and interpretation of the Great Oxidation Event and the Lomagundi-Jatuli Event in the Paleoproterozoic. The amount of organic carbon burial and the size of the seawater sulfate reservoir during this redox transition are uncertain because of inherent limitations in the geochemical record of carbonates. With a multi-proxy geochemical approach to test for diagenetic effects, authigenic minerals, and local artifacts, more robust reconstructions for global carbonate carbon-isotope ratios and sulfur-isotope ratios will be generated for the Paleoproterozoic record in Fennoscandia. These results will be used to generate revised global biogeochemical models for the evolution of Paleoproterozoic surface redox and oxygen production. To help teach about Earth’s redox evolution, hands-on Experience Boxes will be developed that will be available for circulation from the Field Museum’s Harris Learning Collection as well as used in several outreach events by the scientists working on this research.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.