Collaborative Research: Links Between Magma Source Characteristics, Shallow Plumbing, and Eruptive Styles in Mafic Intraplate Volcanic Fields (Lunar Crater Volcanic Field, Nevada)

智力上的优点。在板内区形成的火山，虽然规模很小，而且(主要)是单生的，但它是由喷发现象造成的，从平静的熔岩喷出到相对爆炸性的斯特龙博尔活动，如果外部水与上升的岩浆相互作用，则是水力火山活动。岩浆在分散地区以相对较小的批次产生和喷发，通常有证据表明从上地幔直接上升到地表，这表明驱动过程是强烈的热点式地幔上涌和分散的初始熔体区域的混合，这些区域被构造变形被动动员(分别是火山场的高和低岩浆通量末端成员)。综合物理火山学、岩石学和地球化学的方法可以提供对这些过程以及深部岩浆动力学和地表喷发过程之间的联系的重要见解。由于缺乏长寿的地壳岩浆储集层)，可以研究深部岩浆源(S)和浅层管道系统对喷发方式的影响。推测喷发方式受岩浆源区物理化学特征的影响。为了验证这一假设，将综合来自暴露良好的月球陨石坑火山场(内华达州中部)的综合数据。对喷发相、暴露的浅部管道(在较老的被侵蚀的火山上)和丰富的地幔包体的直接研究将提供对岩浆来源和上升过程的洞察。现有的关于广泛的地球化学趋势和年龄关系的数据将与新的EarthScope地震层析成像数据相结合，以提供一个框架来理解：(1)原有构造、地形和喷口位置之间的相互作用；(2)浅层管道几何形状；(3)对岩浆喷发方式的浅层控制，包括喷发方式、碎屑结构和形状、挥发分含量和矿物化学之间的关系；(4)岩浆源和岩浆分异过程的时空变化；(5)母岩浆的熔融深度和挥发分含量；火山位置、熔融深度和上地幔地震结构之间的对应关系。这项工作将有助于改进火山风险评估，包括未来发生事件的可能性(火山时间和地点)及其后果(与喷发过程有关)。该项目还将支持对三名博士生(其中两名为少数民族女性)的培训，并将作为与墨西哥自治大学火山学和地球化学组的国际合作的一部分。提案团队正在与Shoshone部落(鸭水保护区)和土地管理局进行沟通，以便我们可以与他们以及(通过BLM)与公众分享我们的成果。

Intellectual merit. Volcanoes that form in intraplate fields, although small and (mainly) monogenetic, result from eruptive phenomena ranging from quiet effusion of lava to relatively explosive Strombolian activity and, if external water interacts with ascending magma, hydrovolcanic activity. The generation and eruption of magmas in relatively small batches over dispersed areas, often with evidence for direct ascent from the upper mantle to the surface, suggests a driving process that is hybrid between strong hotspot-style mantle upwelling and scattered pockets of incipient melt that are passively mobilized by tectonic deformation (high- and low-magma flux end members of volcanic fields, respectively).Integrated approaches involving physical volcanology, petrology, and geochemistry can provide important insights into these processes and the links between magma dynamics at depth and eruption processes on the surface. The lack of long-lived crustal magma reservoirs) allows investigation of the influences of deep magma source(s) and shallow plumbing systems on eruption styles. It is hypothesized that eruption style is influenced by physical and chemical characteristics of magma sources. To test this hypothesis comprehensive data will be integrated from the well-exposed Lunar Crater Volcanic Field (central Nevada). Direct studies of eruptive facies, of exposed shallow conduits (at older, eroded volcanoes), and of abundant mantle xenoliths will provide insights into the magma sources and ascent processes. Existing data on broad geochemicsl trends and age relationships will be integrated with new EarthScope seismic tomography data to provide a framework for understanding: (1) the interplay between pre-existing structure, topography, and vent location; (2) shallow plumbing geometries; (3) shallow controls on magmatic eruption styles, including relationships between eruption style, clast texture and shape, volatile content, and mineral chemistry; (4) spatial and temporal variations in magma sources and magma differentiation processes at individual volcanoes and across the field as a whole; (5) depth of melting and volatile contents of parent magmas; and (6) correspondence between volcano location, melting depths, and upper mantle seismic structure.Broader impacts. This work will support improvements in volcanic risk assessment, both in terms of the probability (volcano timing and location) of future events and in terms of their consequences (related to eruption processes). The project will also support the training of three Ph.D. students (two of whom are female minorities) and will have a component of international collaboration with the volcanology and geochemistry group at the Universidad Autónoma de México. The proposing team is in communication both with the Shoshone Tribe (Duckwater Reservation) and the Bureau of Land Management so that we can share our results with them and (through BLM) with the public.