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

职业：了解地球的碳和硫耦合循环在大气氧化后是如何演变的？ i: Clara Blättler（芝加哥大学）这项研究将提高人们对地球作为一个行星在大约23亿年前大气中出现氧气后的进化的理解。该项目将重点研究在这段时间内沉积的一组独特的岩石，并于2007年由一个国际合作组织收集。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上相互关联的地球化学循环。作为这些研究活动的补充，将通过与菲尔德自然历史博物馆的合作，在K-12教育和公共环境中推广地球及其古代环境的历史。将开发一套动手工具包，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和芝加哥当地的外展活动中展出。该项目将测试关于古元古代大氧化事件和Lomagundi-Jatuli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，在这一氧化还原转变过程中，有机碳埋藏量和海水硫酸盐储层的大小尚不确定。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率和硫同位素比率重建。这些结果将用于建立修正的全球生物地球化学模型，用于古元古代地表氧化还原和氧气生成的演化。为了帮助人们了解地球的氧化还原进化，将开发动手体验盒，这些体验盒将从菲尔德博物馆的哈里斯学习收藏中流通，并在从事这项研究的科学家的几次推广活动中使用。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识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.