Collaborative Research: Unlocking the Cenozoic/Cretaceous seawater sulfate record via inclusion of 17O in marine barite

合作研究：通过海洋重晶石中的 17O 来解锁新生代/白垩纪海水硫酸盐记录

• 批准号: 1946137
• 负责人: David Johnston
• 金额: $ 41.34万
• 依托单位: Harvard University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-01-15 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1946137&HistoricalAwards=false
• 关键词: Collaborative; Research; Unlocking; Cenozoic; Cretaceous

The PIs will measure a never-before-analyzed chemical property of ocean sediments – variations in two trace isotopes of oxygen in barium sulfate particles. These data will provide a record of changes in ocean chemistry over the last 125 million years, changes that are driven by variations in the Earth’s carbon, oxygen and sulfur cycles. Understanding the history of the global cycles of these elements (carbon, oxygen, and sulfur) will help us understand the links between geological processes, natural climate change, and biological processes on land and in the ocean. Activities also include public outreach (via cartoon modules described the science), and the project will support training of a graduate student.This project will build a record of the 17O in sulfate from marine barite over the last 125 million years, using a recently-developed method that enables high-precision analysis of 17O in barite. The chemistry of marine sediments stands as one of the central catalogs of climatic evolution and earth surface change on geological timescales. The sulfur and oxygen isotopic composition of marine sulfate (as captured in barite) are two key records ocean chemistry over the last 125 million years. They are important because sulfate serves as an energy source for microbial life that is roughly 10 times larger than atmospheric oxygen, and that integrates across a wide range of biogeochemical processes and cycles, including those of carbon and iron. Recently, a new hypothesis was generated involving the influence of large igneous province formation on the sulfur isotope record. The new data proposed here – 17O in barite – will be used to test this hypothesis, and more broadly, to better understand the C, S, and O cycles through the Cretaceous and Cenozoic.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.

PI 将测量海洋沉积物的一种前所未有的化学性质——硫酸钡颗粒中两种痕量氧同位素的变化。这些数据将提供过去 1.25 亿年海洋化学变化的记录，这些变化是由这些变化引起的。通过地球碳、氧和硫循环的变化了解这些元素（碳、氧和硫）的全球循环历史将有助于我们了解地质过程与自然气候之间的联系。活动还包括公众宣传（通过描述科学的卡通模块），该项目将支持研究生的培训。该项目将建立海洋硫酸盐中 17O 的记录。使用最近开发的方法对过去 1.25 亿年的重晶石进行了高精度分析，该方法能够对重晶石中的 17O 进行高精度分析。海洋沉积物的化学成分是气候演变和地球表面地质变化的核心目录之一。海洋硫酸盐的硫和氧同位素组成（在重晶石中捕获）是过去 1.25 亿年海洋化学的两个关键记录，它们很重要，因为硫酸盐是大约 10 倍的微生物生命的能源。大气中的氧气，并且整合了广泛的生物地球化学过程和循环，包括碳和铁的生物地球化学过程和循环。最近，提出了一个新的假设，涉及大型火成岩省的形成对地球的影响。这里提出的新数据——重晶石中的 17O——将用于检验这一假设，并更广泛地更好地了解白垩纪和新生代的 C、S 和 O 循环。该奖项反映了 NSF 的法定使命和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，该项目被认为值得支持。