Collaborative Research: Using Trace and Ore Elements to Track Volatile Behavior and Fluid Migration within Intermediate-silicic Magma Chambers

合作研究：利用痕量元素和矿石元素追踪中硅质岩浆室内的挥发行为和流体运移

• 批准号: 1219484
• 负责人: James Webster
• 金额: $ 9.93万
• 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: 2012
• 资助国家: 美国
• 起止时间: 2012-08-01 至 2017-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1219484&HistoricalAwards=false
• 关键词: Collaborative; Research; Using; Trace; Ore

The release and movement of magmatic volatile components, including water, carbon dioxide, sulfur, and chlorine, exert significant control on the conditions of volcanic eruptions and on the transport and deposition of potential ore metals. Many of the parameters critical for understanding these processes are invisible to direct observations because they occur up to several kilometers beneath the surface of the Earth. Researchers have suggested that other trace elements both in the magma and in crystals forming within it may be used as a proxy for interpreting volatile behavior in magma and fluids. However many of the basic variables which describe how these elements are incorporated into crystals are unknown or are in question. This study builds off observations about enrichment in different trace elements analyzed in crystals from the recent eruption (2004) of Mount St. Helens by 1) conducting hydrothermal experiments at various conditions to try to better constrain many of these questionable variables and 2) expand on the work at Mount St. Helens to look for similar elemental variations at other volcanoes, including Mt. Pinatubo, Philippines; Augustine volcano, Alaska; and Mt. Guardia, Lipari. Specifically, this work will focus on an experimental and analytical study of the elements, Li, Cu, Zn, Pb, W, and Mo. These elements are of particular interest as prior studies have suggested they are likely to be transported by volatiles (such as water, CO2, etc). The experimental results will be integrated with observations from multiple volcanic centers to fully understand the origins of these element enrichments and how this relates to the movement of volatiles in silicic magma systems and how volatile transfer influences processes of eruption and mineral deposit formation.

岩浆挥发性成分的释放和运动，包括水、二氧化碳、硫和氯，对火山爆发的条件和潜在成矿金属的运输和沉积产生重要的控制作用。许多对理解这些过程至关重要的参数是无法直接观测的，因为它们发生在地球表面以下几公里处。 研究人员认为，岩浆和在其中形成的晶体中的其他微量元素可以用作解释岩浆和流体中挥发性行为的替代物。 然而，许多描述这些元素如何结合到晶体中的基本变量是未知的或有问题的。 这项研究建立了对最近爆发（2004年）的圣海伦斯火山的晶体中分析的不同微量元素富集的观察，1）在各种条件下进行热液实验，试图更好地限制许多这些可疑的变量，2）扩大在圣海伦斯火山的工作，寻找其他火山，包括Mt.皮纳图博，菲律宾;奥古斯丁火山，阿拉斯加;和山。瓜迪亚利帕里具体来说，这项工作将集中在实验和分析研究的元素，锂，铜，锌，铅，钨，钼。 这些元素特别令人感兴趣，因为先前的研究表明它们可能通过挥发物（如水，CO2等）运输。 实验结果将与多个火山中心的观测结果相结合，以充分了解这些元素富集的起源，以及这与岩浆系统中挥发物运动的关系，以及挥发物转移如何影响喷发和矿物存款形成的过程。