Collaborative Research: Tracking the Exsolution and Migration of Volatiles in Shallow Magma Reservoirs

合作研究：追踪浅层岩浆库挥发物的溶出和迁移

• 批准号: 1759583
• 负责人: Denton Ebel
• 金额: $ 17.89万
• 依托单位: American Museum Natural History
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-15 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1759583&HistoricalAwards=false
• 关键词: Collaborative; Research; Tracking; Exsolution; Migration

The exsolution and migration of magmatic volatiles have a profound influence over the chemical and physical evolution of magmas. More specifically, the presence of a discrete volatile phase (gas bubbles) affects the transport of a wide variety of metals in and out of magma bodies leading to ore deposit formation and controls the likelihood of an eruption as well as eruption dynamics. Unfortunately, erupted volcanic deposits or exhumed magma bodies have lost most traces of their volatile cargo; so, information about the timing of exsolution and the efficiency of volatile migration in active magma reservoir remain therefore elusive. The proposed study addresses this gap in knowledge with a combination of field work, mechanical models and laboratory experiments focusing on the behavior of volatiles in shallow magma reservoirs. The main challenges that prevent a better understanding of the dynamics of shallow magmatic volatiles in magma reservoirs are (1) the lack of understanding of the dependence of the solubility of complex magmatic fluids (magmatic volatiles) on pressure, temperature and magma composition -thus requiring new experiments- and (2) the lack of understanding of the physics of deforming three-phase magmas (vapors composed of exsolved volatiles, viscous silicate melts and crystals). The work proposed here will not only address the gap in knowledge of magmatic systems described above, it will also push the boundaries of our understanding of the thermodynamics of complex magmatic fluids (with direct application to the chemistry of metallic ore-forming fluids), and multiphase fluid mechanics. This project will generate a massive, systematic volatile solubility data set for 3 melt compositions; these data are required for future expansion of extant thermodynamic models on volatile and fluid behavior in felsic magmas. This project also features a new collaboration which will provide a postdoc and a graduate student with an opportunity to work with and learn from an interdisciplinary research team at different institutions. The PIs have a record of incorporating diverse and under-represented groups within their research and education programs. For example, women and members of other under-represented groups will participate in Earth science teacher-student training events at the AMNH and in an organized field excursion to the Sterling Hill Zinc Mine and Museum, NJ. The PIs from Brown University will participate in the Leadership Alliance SR-EIP summer program, which brings 1st generation and under-represented minorities undergrads to STEM research.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.

岩浆挥发分的出溶和迁移对岩浆的化学和物理演化有着深远的影响。更具体地说，离散挥发相（气泡）的存在会影响多种金属进出岩浆体的运输，从而导致矿床的形成，并控制喷发的可能性以及喷发动力学。不幸的是，喷发的火山沉积物或挖出的岩浆体已经失去了大部分挥发性物质的痕迹。因此，有关活动岩浆储层中溶出时间和挥发物迁移效率的信息仍然难以捉摸。拟议的研究通过结合现场工作、力学模型和实验室实验来解决这一知识空白，重点关注浅层岩浆储层中挥发物的行为。阻碍更好地了解岩浆储层中浅层岩浆挥发物动态的主要挑战是（1）缺乏对复杂岩浆流体（岩浆挥发物）溶解度对压力、温度和岩浆成分的依赖性的了解，因此需要新实验 - 以及（2）缺乏对变形三相岩浆（由溶解的挥发物、粘性硅酸盐熔体和晶体组成的蒸气）的物理学的了解。这里提出的工作不仅将解决上述岩浆系统知识的空白，还将突破我们对复杂岩浆流体热力学理解的界限（直接应用于金属成矿流体的化学），并且多相流体力学。该项目将为 3 种熔体成分生成大量、系统的挥发性溶解度数据集；这些数据对于未来扩展关于长英质岩浆挥发物和流体行为的现有热力学模型是必需的。该项目还包括一项新的合作，将为博士后和研究生提供与不同机构的跨学科研究团队合作并向其学习的机会。 PI 有着将多元化和代表性不足的群体纳入其研究和教育项目的记录。例如，妇女和其他代表性不足群体的成员将参加 AMNH 的地球科学师生培训活动，以及有组织的新泽西州斯特林山锌矿和博物馆实地考察活动。布朗大学的 PI 将参加领导力联盟 SR-EIP 夏季项目，该项目将第一代和代表性不足的少数族裔本科生带入 STEM 研究。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力评估进行评估，认为值得支持。优点和更广泛的影响审查标准。