Collaborative Research: How are Rhyolites Generated? Evaluating Models for the Volcanic-plutonic Connection in the Searchlight Magmatic System, Nevada

合作研究：流纹岩是如何产生的？

• 批准号: 2007057
• 负责人: Ayla Pamukcu
• 金额: $ 13.29万
• 依托单位: Stanford University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-19 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2007057&HistoricalAwards=false
• 关键词: Collaborative; Research; How; Rhyolites; Generated

Eruptions of high-silica rhyolite magma are explosive, violent, and potentially extremely hazardous events. However, questions of how, under what conditions, and over what timescales the magma bodies that source these eruptions are assembled remain debated. Resolving these issues is critical for understanding a variety of magmatic and crustal processes, ranging from the geochemical stratification of the crust to monitoring the volcanoes that source such dangerous eruptions for future hazards. A significant challenge to answering these questions lies in the difficulty in documenting the physical (e.g., temperature, pressure) and geochemical conditions in magmatic systems through time. Geophysical measurements on modern volcanoes can provide 'snapshots' of a magmatic system, but they cannot shed light on long-term changes that occur over tens of thousands to millions of years. One way to bridge this gap is to study ancient volcanoes where faulting and erosion have exposed both the material that erupted from the volcano and the un-erupted material that comprises the roots of these systems within the Earth's crust. Used in combination, these extrusive and intrusive deposits can be a powerful tool to understand longer-term processes. This project aims to investigate one such ancient volcano near Searchlight, Nevada (USA). More specifically, the PIs will produce a high-resolution (50,000 years) temporal record spanning the magmatic system's 1-2 million year lifetime, with which they will establish the history of magma emplacement in the crust, geochemical trends, and the relative timing of the eruption(s). To do this, the researchers will utilize high-precision U-Pb zircon geochronology, whole-rock and mineral geochemistry and barometry, and thermal models. This record will shed light on the timescales over which magmas accumulate and are stored within the Earth's upper crust, the processes that occur in and affect the magma body prior to eruption, and potential eruption triggers. Funding will also support two postdoctoral researchers (1 female), research opportunities for undergraduate students at Princeton and Northeastern Universities, and participation in Princeton University's Teachers as Scholars program, which introduces local K-12 teachers to the Earth sciences and helps them in building science curricula for use in their classrooms.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.

高硅流纹岩岩浆的喷发是爆炸性的、猛烈的和潜在的极其危险的事件。然而，关于如何、在什么条件下以及在什么时间尺度上聚集产生这些喷发的岩浆体的问题仍然存在争议。解决这些问题对于了解各种岩浆和地壳过程至关重要，从地壳的地球化学分层到监测火山为未来的灾害造成这种危险的喷发。回答这些问题的一个重大挑战在于难以记录岩浆系统中随时间推移的物理(例如，温度、压力)和地球化学条件。对现代火山的地球物理测量可以提供岩浆系统的“快照”，但它们不能揭示发生在数万年到数百万年之间的长期变化。弥补这一差距的一种方法是研究古火山，在那里，断层和侵蚀暴露了火山喷发出的物质和构成地壳内这些系统的根的未喷发物质。结合使用，这些喷出和侵入沉积可以成为了解较长期过程的有力工具。该项目旨在调查美国内华达州Searchlight附近的一座这样的古老火山。更具体地说，PI将产生跨越岩浆系统100-200万年寿命的高分辨率(5万年)时间记录，利用该记录将建立地壳中岩浆侵位的历史、地球化学趋势和喷发的相对时间(S)。为了做到这一点，研究人员将利用高精度的锆石U-Pb年代学、全岩和矿物地球化学和气压测量以及热模型。这一记录将揭示岩浆积累和储存在地球上地壳内的时间尺度，喷发前发生在岩浆体中并对其产生影响的过程，以及潜在的喷发触发因素。资金还将支持两名博士后研究人员(1名女性)，为普林斯顿大学和东北大学的本科生提供研究机会，并参与普林斯顿大学的教师学者计划，该计划向当地K-12教师介绍地球科学，并帮助他们制定科学课程，供他们在课堂上使用。该奖项反映了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。