CAREER: The Evolution of Super-Hydrous Magmas in the Earth's Crust

职业：地壳中超含水岩浆的演化

• 批准号: 2047960
• 负责人: Michael Krawczynski
• 金额: $ 56.72万
• 依托单位: Washington University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-01 至 2026-06-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2047960&HistoricalAwards=false
• 关键词: CAREER; Evolution; Super; Hydrous; Magmas

Petrology and geochemistry are cornerstones of geology and the study of Earth systems and processes. Experimental studies have often been the necessary component for advances in understanding plate tectonics and subduction zones in particular. This proposal describes an integrated research and teaching program with foundations in experimental petrology, thermodynamics, and volcanology, to advance the understanding of how volcanoes work, how water affects the evolution of volcanoes and their behavior, while providing new hands-on teaching tools to generate excitement for future petrologists currently at the graduate, undergraduate or high school level. In particular, this proposal will study the eruptive products from the most explosively active volcano in the world. The research proposed here is an experimental and geochemical study primarily designed to use amphibole chemistry to quantify pre-eruptive water contents in super-hydrous arc magmas at deep crustal and upper mantle conditions. This study consists of 3 broad research tasks that will form the foundation of a new paradigm for understanding volatile flux and recycling in the Earth, and an education plan that will develop new ways of bringing technology and teaching petrology together in the classroom. This project will undertake four interrelated tasks aimed at studying the pre-eruption dynamics of magma storage and evolution in the most magmatically productive volcanic area of the world and focuses specifically on geochemistry related to super-hydrous magmas. Experiments are to be executed with the broad goal of bridging the gap in our knowledge about magmatic water contents between the termination of hydrous flux melting, and the trapping of melt inclusions and crystallization of plagioclase in the shallow crust. Experimental studies will explore the geochemical evolution of hydrous magmas and make the first quantitative measurements on hydrogen, fluorine, and chlorine partitioning in amphibole at lower crustal conditions. Measuring the H contents in amphiboles will provide immense geologic value only if we can account for the intensive and extensive variables that control the geochemical partitioning between melt and crystal, and the dehydrogenation of amphibole. Amphibole synthesis experiments at controlled P, T, XH2O and fO2 will be conducted. Results will be incorporated into databases such as LEPR and be available to incorporate into important community thermodynamic models such as MELTS and its successor ENKI. Currently, amphibole is the only major phase not included in these modeling algorithms, highlighting the importance of general experimental studies on this mineral. There is a paucity of hydrous experiments at lower crustal pressures in the literature and these experiments will help to fill that gap. This study will be expanding our current knowledge of the stability of amphibole, an important phase in Earth's crust, but one without a low-pressure stability field so it has often gone under-appreciated in its role in producing geochemical trends at arcs.Through the CAREER program, the PI will develop new teaching and outreach tools that will improve the way ternary phase diagrams are taught in petrology classes, as well as produce 3D models of volcanoes that can be used for virtual field trips and volcanology outreach. The objectives of this effort are to: 1. Create hands-on methods for teaching petrology and volcanology to undergraduate students, to improve understanding and retention. 2. Create pathways to generate excitement in these subjects among undergraduates by making the new visualizations available for distribution to other undergraduate institutions. To achieve these goals a plan will be implemented that includes software development, curriculumdevelopment, and distribution of 3D renderings to the AR app platform.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.

岩石学和地球化学是地质学和地球系统和过程研究的基石。实验研究往往是理解板块构造和俯冲带的必要组成部分。 该提案描述了一个综合的研究和教学计划，以实验岩石学，热力学和火山学为基础，以促进对火山如何工作，水如何影响火山及其行为的演变的理解，同时提供新的实践教学工具，为目前在研究生，本科生或高中水平的未来岩石学家带来兴奋。特别是，这项建议将研究世界上最活跃的火山爆发的产物。 这里提出的研究是一个实验和地球化学研究，主要目的是使用角闪石化学定量喷发前的水含量在超含水弧岩浆在地壳深部和上地幔条件。这项研究包括3个广泛的研究任务，将形成一个新的范式的基础，以了解挥发通量和地球中的再循环，以及一个教育计划，将开发新的方法，使技术和教学岩石学在课堂上一起。该项目将进行四项相互关联的任务，目的是研究世界上最具岩浆生产力的火山地区的岩浆储存和演化的喷发前动力学，并特别侧重于与超含水岩浆有关的地球化学。实验的广泛目标是弥合我们对含水通量熔融终止与熔融包裹体捕获和斜长石在地壳浅部结晶之间的岩浆水含量的认识上的差距。实验研究将探索含水岩浆的地球化学演化，并首次定量测量下地壳条件下角闪石中氢、氟和氯的分配。只有当我们能够解释控制熔体和晶体之间的地球化学分配以及角闪石的脱氢作用的密集和广泛的变量时，测量角闪石中的H含量才能提供巨大的地质价值。将在控制P、T、XH2O和fO2的条件下进行角闪石合成实验。结果将被纳入数据库，如LEPR，并可纳入重要的社区热力学模型，如MELTS及其继任者ENKI。目前，角闪石是唯一的主要阶段，不包括在这些建模算法，突出了一般实验研究的重要性，这种mineral.There是一个缺乏在较低的地壳压力在文献中的含水实验，这些实验将有助于填补这一空白。这项研究将扩大我们目前对角闪石稳定性的认识，角闪石是地壳中的一个重要相，但它没有低压稳定场，因此它在产生弧的地球化学趋势方面的作用常常被低估。通过CAREER计划，PI将开发新的教学和推广工具，改善岩石学课程中三元相图的教学方式，以及制作火山的3D模型，可用于虚拟实地考察和火山学推广。这项工作的目标是：1.为本科生创建教授岩石学和火山学的实践方法，以提高理解和保留。2.通过将新的可视化分发给其他本科院校，创建途径，在本科生中产生对这些学科的兴奋。为了实现这些目标，将实施一项计划，其中包括软件开发、软件开发和将3D渲染分发到AR应用程序平台。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。