Integrating petrologic records and geodynamics: Quantifying the effects of glaciation on crustal stress and eruptive patterns at Mt. Waesche, Executive Committee Range, Antarctica

整合岩石学记录和地球动力学：量化冰川作用对南极洲执行委员会山脉韦什山地壳应力和喷发模式的影响

• 批准号: 2122248
• 负责人: Laura Waters
• 金额: $ 48.3万
• 依托单位: New Mexico Institute of Mining and Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-15 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2122248&HistoricalAwards=false
• 关键词: Integrating; petrologic; records; geodynamics; Quantifying

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).The geologic record reveals that volcanic activity increases when glaciers retreat and major ice sheets thin. This relationship produces a positive feedback mechanism where the uptick in volcanism increases greenhouse gasses concentrations, leading to climate warming and further deglaciation. Although the pattern between volcanism and deglaciation is observed in the geologic record, the exact mechanism(s) by which glaciers impact a volcanic plumbing system is unknown. This project focuses on Mount Waesche, a volcano in West Antarctica, that frequently erupts during warm, interglacial periods and undergoes a period of less activity during cold, glacial periods. This project will examine compositions of the rocks and minerals from Mount Waesche to determine magma storage depths, allowing the investigators to understand how magma plumbing systems change in response to glacial cycles. These results will be compared with geodynamic simulations to understand the physics behind the effects of deglaciation on the magmatic plumbing systems within Earth’s crust. The investigators will additionally partner with Mentoring Kids Works to develop several Polar and Earth Science Educational Modules aimed at improving reading skills in third grade students in New Mexico. The proposed Polar and Earth Science program consists of modules that include readings of books introducing students to Earth and Polar science themes, paired with Earth and Polar Science activities, followed by simple experiments, where students make predictions and collect data. Information required to implement our Polar and Earth Science curriculum will be made available online.Isotopic and sedimentary datasets reveal that volcanic activity typically increases during interglacial periods. However, the physical mechanisms through which changes in the surface loading affect volcanic magmatic plumbing systems remain unconstrained. Recently generated 40Ar/39Ar eruption ages indicate that 86% of the dated samples from Mt. Waesche, a late Quaternary volcano in Marie Byrd land, correlate with interglacial periods, suggesting this volcano uniquely responds to changes in the West Antarctic Ice Sheet. We propose to combine the petrology of Mount Waesche’s volcanic record, constraints on changing ice loads through time, and geodynamic modelling to: (1) Determine how pre-eruptive storage conditions change during glacial and interglacial periods using whole rock and mineral compositions of volcanic rocks; (2) Conduct geodynamic modeling to elucidate the relationship between lithospheric structure, temporal variations in ice sheet thickness, and subsequent changes in crustal stresses and magmatic transport and, therefore, the mechanism(s) by which deglaciation impacts magmatic plumbing systems; (3) Use the outcomes of objectives (1) and (2) to provide new constraints on the changes in ice sheet thickness through time that could plausibly trigger future volcanic and magmatic activity in West Antarctica. This collaborative approach will provide a novel methodology to determine prior magnitudes and rates of ice load changes within the Marie Byrd Land region of Antarctica. Lastly, estimates of WAIS elevation changes from this study will be compared to ongoing studies at Mount Waesche focused on constraining last interglacial ice sheet draw down using cosmogenic exposure ages obtained from shallow drilling. The scope of work also includes a partnership with Mentoring Kids Works to develop several Polar and Earth Science Educational Modules aimed at improving reading skills in third grade students in New Mexico. The proposed Polar and Earth Science program consists of modules that include readings of books introducing students to Earth and Polar science themes, paired with Earth and Polar Science activities, followed by simple experiments, where students make predictions and collect data. Information required to implement our Polar and Earth Science curriculum will be made available online.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.

该奖项的全部或部分资金来自《2021年美国救援计划法案》(公法117-2)。地质记录显示，当冰川消退，主要冰盖变薄时，火山活动会增加。这种关系产生了一种正反馈机制，火山活动的上升增加了温室气体的浓度，导致气候变暖和进一步的冰川消融。尽管在地质记录中观察到了火山作用和冰川消融之间的模式，但冰川撞击火山管道系统的确切机制(S)尚不清楚。该项目的重点是南极洲西部的Wesche火山，该火山在温暖的间冰期频繁喷发，在寒冷的冰期经历一段活动较少的时期。该项目将检查来自威斯切山的岩石和矿物的组成，以确定岩浆储存深度，使研究人员能够了解岩浆管道系统如何随着冰川周期的变化而变化。这些结果将与地球动力学模拟相比较，以了解冰川消融对地壳内岩浆管道系统影响背后的物理机制。调查人员还将与辅导儿童工作公司合作开发几个极地和地球科学教育模块，旨在提高新墨西哥州三年级学生的阅读技能。拟议的极地和地球科学课程包括阅读向学生介绍地球和极地科学主题的书籍，与地球和极地科学活动配对，然后是简单的实验，学生在这些实验中做出预测并收集数据。实施我们的极地和地球科学课程所需的信息将在网上提供。同位数据和沉积数据显示，火山活动通常在间冰期增加。然而，地表负荷变化影响火山岩浆管道系统的物理机制仍然不受限制。最近产生的40Ar/39Ar喷发年龄表明，86%的年代样品来自山体。Wesche火山是玛丽·伯德陆地上的一座第四纪晚期火山，与间冰期有关，表明这座火山对西南极冰盖的变化做出了独特的反应。我们建议结合威斯切山火山记录的岩石学、对冰负荷随时间变化的约束和地球动力学模拟来：(1)利用火山岩的全岩和矿物成分来确定喷发前的储存条件在冰期和间冰期是如何变化的；(2)进行地球动力学模拟来阐明岩石圈结构、冰盖厚度的时间变化以及随后地壳应力和岩浆输送的变化之间的关系，从而阐明冰川消融影响岩浆管道系统的机制(S)；(3)利用目标(1)和(2)的结果，对冰盖厚度随时间的变化提供新的约束，这些变化可能会引发未来南极洲西部的火山和岩浆活动。这种协作方法将提供一种新的方法来确定南极洲马里伯德陆地区域内先前的冰负荷变化幅度和速率。最后，这项研究对WAIS海拔变化的估计将与Wesche山正在进行的研究进行比较，这些研究的重点是利用浅层钻探获得的宇宙成因暴露年龄来限制最后一次间冰川冰盖的下降。工作范围还包括与辅导儿童工作建立伙伴关系，开发几个极地和地球科学教育模块，旨在提高新墨西哥州三年级学生的阅读技能。拟议的极地和地球科学课程包括阅读向学生介绍地球和极地科学主题的书籍，与地球和极地科学活动配对，然后是简单的实验，学生在这些实验中做出预测并收集数据。实施我们的极地和地球科学课程所需的信息将在网上提供。这一奖项反映了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。