EAR-PF The Role of Deformation in Triggering Volcanic Eruptions

EAR-PF 变形在引发火山喷发中的作用

• 批准号: 2052599
• 负责人: Amy Ryan
• 金额: $ 17.4万
• 依托单位: Ryan, Amy Grace
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2052599&HistoricalAwards=false
• 关键词: EAR; PF; Role; Deformation; Triggering

Dr. Amy Ryan has been awarded an NSF EAR Postdoctoral Fellowship to carry out research at the University of Minnesota to determine the role that deformation of magma chambers plays in setting off volcanic eruptions. Supervolcanoes like Yellowstone volcano (USA) are fed by magma chambers that have small pockets of fluid magma distributed within a body of immobile magma “mush, dominated by crystals with magma filling in spaces between. Volcanic eruptions and associated unrest occur when physical forces cause changes in the Earth’s crust and those pockets move through the mush to the surface. Studies of erupted lavas have shown that this movement can occur suddenly, geologically speaking, taking as little as a few months to hundreds of years. However, the physical conditions and processes that allow the fluid magma to move through the stiff, immobile mush are unknown. Dr Ryan’s work includes experiments that recreate conditions beneath supervolcanoes to characterize the geologic processes that drive magma movement beneath volcanoes. The results of Dr. Ryan’s study will provide insight into the conditions that lead to increased volcanic unrest and help those monitoring active volcanoes to create better risk mitigation strategies. The work includes field work in northern Minnesota. Dr. Ryan will partner with the Wolf Ridge Learning Center to develop Next Generation Science Standard (NGSS)-aligned classroom lessons for K-12 students, as well as a series of interactive field guides. Additionally, Dr. Ryan will mentor undergraduates in all aspects of research and the development of educational materials. Dr. Ryan will be conducting high-temperature and high-pressure deformation experiments in a gas-medium, Paterson apparatus. Experimental samples will consist of a disk of glass (“magma”) stacked in series with a disk of a composite (“mush”) composed of crushed glass mixed with fine quartz sand up to a crystal fraction of 80%. Samples will be heated and pressurized then be subjected to pore-pressure gradients, compressed or sheared at rates and magnitudes representative of deformation conditions mushes and magmas experience in natural reservoirs. Following deformation, analyses of samples will include specialized imaging to look for magma infiltration structures and to measure the volume of migrated magma. The major project objectives are to (1) determine the deformational conditions (type, rate and magnitude) that create dilatant regions in the high-viscosity, low-permeability mush that allow for magma infiltration and (2) based on experimental results, identify the multi-scale geologic processes that can feasibly trigger magma infiltration and, as a result, reservoir reorganization. These results will find application in constraining input parameters for numerical models of magma extraction and transport in the upper crust. Research outputs from this project will be disseminated in high-impact, open-access, peer-reviewed articles, conference presentations, public lectures, university-based websites and social media. In addition, the project will also include a field study to compare textures that form in experiments to those that developed in natural intrusive bodies and are preserved in the rock record. Field work will involve the participation of students from local community or tribal colleges. Finally, educational materials will be developed based on the experimental work and field study and be made available for local learning centers and schools.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.

艾米·瑞安博士获得了NSF EAR博士后奖学金，他将在明尼苏达大学进行研究，以确定岩浆室的变形在引发火山喷发中所起的作用。像黄石火山(美国)这样的超级火山是由岩浆室提供的，这些岩浆室有小块的流体岩浆分布在不动的岩浆体内，由晶体主导，中间填充着岩浆。当物理力量引起地壳变化时，火山喷发和相关的动荡就会发生，这些口袋通过泥浆移动到地表。对喷发的熔岩的研究表明，从地质学的角度讲，这种运动可以突然发生，只需几个月到数百年的时间。然而，允许流体岩浆通过僵硬、静止的泥浆的物理条件和过程尚不清楚。瑞安博士的工作包括在超级火山下重建条件的实验，以表征驱动火山下岩浆运动的地质过程。瑞安博士的研究结果将提供对导致火山骚乱加剧的条件的洞察，并帮助那些监测活火山的人制定更好的风险缓解策略。这项工作包括在明尼苏达州北部的实地工作。Ryan博士将与Wolf Ridge学习中心合作，为K-12学生开发与下一代科学标准(NGSS)一致的课堂课程，以及一系列互动现场指南。此外，瑞安博士还将在研究和教材开发的各个方面指导本科生。瑞安博士将在气体介质的帕特森装置中进行高温高压变形实验。实验样品将由一个玻璃圆盘(“岩浆”)与一个由碎玻璃和细石英砂混合而成的复合圆盘(“糊状”)串联组成，石英砂的结晶度高达80%。样品将被加热和加压，然后受到孔隙压力梯度的影响，压缩或剪切的速度和幅度代表了天然储层中的泥浆和岩浆所经历的变形条件。变形后，对样品的分析将包括专门的成像，以寻找岩浆渗透结构和测量迁移的岩浆体积。项目的主要目标是(1)确定在高粘度、低渗透率的泥浆中形成允许岩浆渗入的扩张区的变形条件(类型、速率和大小)，以及(2)根据实验结果，确定可能触发岩浆渗入的多尺度地质过程，从而进行储集层重组。这些结果将用于约束上地壳岩浆提取和运移数值模型的输入参数。该项目的研究成果将以影响大、开放获取、同行评议的文章、会议报告、公开讲座、大学网站和社交媒体的形式传播。此外，该项目还将包括一项实地研究，将实验中形成的纹理与在自然侵入体中形成并保存在岩石记录中的纹理进行比较。实地考察将有来自当地社区或部落学院的学生参与。最后，将在实验工作和实地研究的基础上开发教育材料，并提供给当地的学习中心和学校。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。

项目成果

Melt Migration in Crystal Mushes by Viscous Fingering: Insights From High‐Temperature, High‐Pressure Experiments

通过粘性指法研究水晶糊中的熔体迁移：来自高温、高压实验的见解

• DOI: 10.1029/2022jb024447
• 发表时间: 2022
• 期刊: Journal of Geophysical Research: Solid Earth
• 作者: Ryan, Amy G.;Hansen, Lars N.;Zimmerman, Mark E.;Pistone, Mattia
• 通讯作者: Pistone, Mattia

Melt migration in crystal mushes by viscous fingering: insights from high-temperature, high-pressure experiments (DATA)

通过粘性指法进行晶体糊中的熔体迁移：来自高温高压实验的见解（数据）

• DOI: 10.17632/rhb2938m52.1
• 发表时间: 2022
• 期刊: Mendeley
• 作者: Ryan, Amy