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

知识价值。在板块内形成的火山，虽然规模很小，而且（主要）是单一成因的，但它们是由喷发现象造成的，从安静的熔岩渗出到相对爆炸性的斯特龙堡活动，如果外部的水与上升的岩浆相互作用，就会形成水火山活动。相对小批量的岩浆在分散区域的产生和喷发，通常有证据表明岩浆从上地幔直接上升到地表，这表明岩浆的驱动过程是强烈的热点式地幔上涌和分散的早期熔体（分别是火山场的高岩浆通量端和低岩浆通量端成员）被动动员的混合过程。包括物理火山学、岩石学和地球化学在内的综合方法可以为这些过程以及深部岩浆动力学与地表喷发过程之间的联系提供重要的见解。长期地壳岩浆储层的缺乏使得研究深部岩浆源和浅层管道系统对喷发样式的影响成为可能。岩浆源的物理化学特征对喷发方式有一定的影响。为了验证这一假设，将整合来自暴露良好的月球陨石坑火山场（内华达中部）的综合数据。直接研究喷发相、暴露的浅层导管（在较老的、受侵蚀的火山上）和丰富的地幔捕虏体，将有助于深入了解岩浆来源和上升过程。现有的广泛的地球化学趋势和年龄关系数据将与新的EarthScope地震层析成像数据相结合，以提供一个框架来理解：(1)预先存在的结构、地形和火山口位置之间的相互作用；(2)浅水暖几何形状；(3)岩浆喷发类型的浅层控制，包括喷发类型、碎屑结构和形状、挥发物含量和矿物化学的关系；(4)单个火山和整个火山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物含量；(6)火山位置、熔融深度与上地幔地震构造的对应关系。更广泛的影响。这项工作将支持改进火山风险评估，包括未来事件的概率（火山时间和位置）及其后果（与喷发过程有关）。该项目还将支助培训三名博士生（其中两名是少数族裔女性），并将成为与Autónoma德姆萨西科大学火山学和地球化学小组国际合作的一个组成部分。提案团队正在与肖肖尼部落（达克沃特保留地）和土地管理局进行沟通，以便我们可以与他们分享我们的结果，并（通过BLM）与公众分享我们的结果。

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.