EAR-PF: Unleashing the petrogenetic potential of sanidine using a combined compositional, experimental, and 3D textural approach

EAR-PF：使用组合的成分、实验和 3D 结构方法释放 Sanidine 的成岩潜力

• 批准号: 1952808
• 负责人: Hannah Shamloo
• 金额: $ 17.4万
• 依托单位: Shamloo, Hannah I
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-06-01 至 2024-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1952808&HistoricalAwards=false
• 关键词: EAR; PF; Unleashing; petrogenetic; potential

Dr. Hannah Shamloo has been granted an NSF EAR Postdoctoral Fellowship to carry out research and educational plans at Oregon State University alongside mentor, Professor Adam Kent. This investigation will examine the processes that produce some of the largest volcanic eruptions known, through the study of minerals present in erupted magmas. The tool developed will help to accurately and quantitively resolve the many processes recorded in zoned minerals that lead to large eruptions. The information for relating magmatic/volcanic processes obtained from individual Barium (Ba) zoning in minerals is critical to the real-time volcano monitoring efforts of future eruptions. This study will consist of three components, (1) quantifying chemical characteristics of natural zoned sanidine from supervolcanoes, (2) perform novel 3D textural characterization of Ba zoning in sanidine, and (3) conduct a series of experiments under relevant conditions to shallow and evolved magmatic systems to constrain the behavior of Ba and other trace elements in sanidine. Additionally, the education plan will entail research opportunities for undergraduates related to this project, teaching opportunities with a focus on minorities in STEM, and outreach via social media.This investigation will better resolve large-scale processes recorded in zoned minerals including pluton formation, initiation of volcanic eruptions, and formation of continental crust. Although the zoning of Ba in sanidine and other alkali-feldspar has been widely documented since at least the 1970’s, its use as a quantitative tool is severely limited by a lack of fundamental data, and as a result, hypotheses based on Ba zoning are often difficult to test. This study will couple in-situ major- and trace-element characterization of natural zoned sanidine from a variety of supervolcanoes using laser ablation ICP-MS and electron microprobe, with 3D textural characterization of Ba zoning using high-resolution X-ray microtomography. Additionally, a series of experiments will be performed under the relevant conditions to shallow and evolved magmatic systems using cold-seal pressure vessels and non-end-loaded piston cylinders to quantify the partitioning behavior of Ba in sanidine and silicic melt. This investigation will also develop a novel technique to study chemical zoning in crystals in 3D rather than the traditional 2D approach often used in petrology that can lead to additional uncertainty. Broader impacts include research opportunities for undergraduate students that will focus on recruiting members of unrepresented minorities in STEM majors. This project received co-funding from the Petrology and Geochemistry program in the division of Earth Sciences.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.

Hannah Shamloo博士获得了NSF EAR博士后奖学金，与导师亚当·肯特教授一起在俄勒冈州立大学开展研究和教育计划。这项调查将通过研究喷发岩浆中存在的矿物，来研究产生一些已知的最大火山喷发的过程。开发的工具将有助于准确和定量地解决分带矿物中记录的导致大规模喷发的许多过程。从矿物中单独的钡(Ba)分带中获得的有关岩浆/火山过程的信息，对于实时监测未来喷发的火山活动至关重要。这项研究将包括三个部分，(1)对来自超级火山的自然分带辉长岩的化学特征进行量化，(2)对辉长岩中的Ba分带进行新的三维结构表征，以及(3)在相关条件下对浅层和演化的岩浆系统进行一系列实验，以约束Ba和其他微量元素在辉长岩中的行为。此外，教育计划将为本科生提供与这一项目相关的研究机会，以STEM少数民族为重点的教学机会，以及通过社交媒体进行宣传。这项调查将更好地解决带状矿物中记录的大规模过程，包括岩体形成、火山喷发和大陆壳形成。尽管玄武岩和其他碱性长石中的Ba分带至少从20世纪70年代起就有了广泛的文献记载，但由于缺乏基础数据，它作为定量工具的使用受到严重限制，因此，基于Ba分带的假说往往难以检验。这项研究将使用激光烧蚀电感耦合等离子体质谱仪和电子探针对来自各种超级火山的自然分带辉长岩进行主元素和微量元素的现场表征，并使用高分辨率X射线显微层析成像对Ba带的3D结构进行表征。此外，还将在相关条件下对浅层和演化的岩浆系统进行一系列实验，使用冷密封压力容器和非端载活塞圆柱体来量化Ba在辉长岩和硅质熔体中的分配行为。这项研究还将开发一种新的技术来研究晶体中的3D化学分区，而不是岩石学中经常使用的传统2D方法，这可能会导致额外的不确定性。更广泛的影响包括为本科生提供研究机会，这些机会将集中在招收STEM专业中没有代表性的少数族裔成员。这个项目得到了地球科学部岩石学和地球化学项目的共同资助。这个奖项反映了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。