EA: Acquisition of an IRMS for sulfur isotope measurements

这笔赠款将用于购买一台最先进的质谱仪。该仪器将作为布朗大学地球、环境和行星科学系的新教员，用于多廷博士的研究项目。硫是元素周期表上的第16个元素，有4个稳定同位素(32S、33S、34S和36S)。在各种岩石材料中测量的这些同位素的比率通常会提供与岩石材料在整个地质时期是如何加工有关的指纹。这也可以提供对随着时间发生的不同行星进化过程的洞察。拟议项目的重点是购置一台能够高精度测量硫同位素比率的最先进仪器。该仪器将主要用于与以下相关的研究：(1)了解地球深处硫的来源和演化，(2)限制地球大气的演化，以及(3)最终解开与地球大气、表面和内部相互作用相关的复杂性。该仪器还将被用作教学工具。预计本科生、研究生和博士后将在各自的项目中使用该仪器。他们将接受仪器操作和故障排除方面的培训。该仪器还将被纳入高级本科生/研究生课程，使学生能够接触到气源质谱学，并有机会在班级内的同位素实验室工作。获奖的提案包括一项要求使用同位素比质谱仪(IRMS)的请求，该仪器将用于确定来自各种地球储集层的岩石的硫同位素组成。收购IRMS将支持Pi(Dottin)的研究计划，Pi将于2023年7月1日开始在布朗大学担任助理教授。使用最先进的IRMS完成的分析任务将广泛包括研究存在于多个地球储存库中的硫的四重同位素组成，以确定与地球内部、地表和大气中硫的循环相关的过程，以及这些过程发生的时间尺度。具体地说，多丁计划利用该仪器：(1)确定洋岛玄武岩中喷发的再循环成分的性质和相对年龄；(2)对原始地幔的硫同位素组成施加详细限制；以及(3)利用S同位素追踪跨越太古代-元古代界线的地球大陆地壳的演化。该仪器将包含最先进的技术，并可配备一套独特的收集器，以便获取硫的次要同位素的高精度测量。在严格获取数据的范围之外，该仪器将与植根于教育、培训和地球科学多样化的努力相联系。申请的仪器将用于支持布朗大学本科生和从HBCU和其他为少数群体服务的机构积极招募的暑期研究本科生进行的研究。此外，该工具还将被用作教育/培训工具。研究生将接受熟练操作和维护仪器的培训，PI(Dottin)计划开发将该仪器用作教学辅助工具的课程，让更多的学生了解气源质谱学和地球化学实验室应用。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This grant will support the acquisition of a state-of-the-art mass spectrometer. The instrument will be used in Dr. Dottin’s research program as a new faculty member at Brown University in the Department of Earth, Environmental, and Planetary Sciences. Sulfur, the sixteenth element on the periodic table, has 4 stable isotopes (32S, 33S, 34S and 36S). Ratios of these isotopes that are measured in a variety of rock materials often provide fingerprints associated with how the rock materials have been processed throughout geologic time. Such can also provide insights into the different planetary evolutionary processes that have occurred through time. The proposed project focuses on the acquisition of a state-of-the-art instrument capable of measuring the ratios of sulfur isotopes at high precision. The instrument will primarily be used for research associated with (1) understanding the origin and evolution of sulfur in the deep Earth, (2) placing constraints on the evolution of Earth’s atmosphere, and (3) ultimately deconvoluting the complexities related to interactions among Earth’s atmosphere, surface, and interior. The instrument also will be used as a teaching tool. It is anticipated that undergraduate students, graduate students, and postdocs will use the instrument for their respective projects. They will be trained in the operation and troubleshooting of the instrument. The instrument also will be incorporated in upper-level undergraduate/graduate courses that will allow students exposure to gas source mass spectrometry and an opportunity to work in an isotope laboratory within a class setting.The awarded proposal contains a request for an isotope ratio mass spectrometer (IRMS) that will be used to determine sulfur isotope compositions of rocks from a variety of Earth reservoirs. Acquisition of an IRMS will support the research program of PI (Dottin), who will begin an assistant professorship at Brown University July 1, 2023. The analytical tasks that will be accomplished with the state-of-the-art IRMS will broadly cover studying the quadruple isotopic composition of sulfur that exists in multiple earth reservoirs to identify the processes associated with the cycling of sulfur among the Earth’s interior, surface, and atmosphere, and the timescales on which these processes occur. Specifically, Dottin plans to use the instrument to: (1) determine the nature and relative age of recycled components erupted among Ocean Island Basalts; (2) place detailed constraints on the sulfur isotope composition of the primordial mantle; and (3) to use S isotopes to track the evolution of Earth’s continental crust across the Archean-Proterozoic boundary. The instrument will contain state-of-the-art technology and can be fit with a unique set of collectors that will allow for the acquisition of high-precision measurements of the minor isotopes of sulfur. Beyond the scope of strictly acquiring data, the instrument will be connected to efforts that are rooted in education, training, and diversification of the geosciences. The instrument requested will be used to support research performed by undergraduate students at Brown University and summer research undergraduate students actively recruited from HBCU’s and other minority-serving institutions. Additionally, the instrument will be used as an educational/training tool. Graduate students will be trained in the proficient operation and maintenance of the instrument and the PI (Dottin) plans to develop courses that use the instrument as a teaching aid to expose a wide audience of students to gas source mass spectrometry and geochemistry laboratory applications.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.