Collaborative Research: The interplay of surface evolution, shallow magmatism, a large hydrothermal system, and hazards at Puyehue-Cordon Caulle Volcanic Complex, Chile

火山景观给当地和区域社区带来了各种自然灾害，包括火山爆发和熔岩涌出、造成陡峭地形的大规模滑坡以及浅层热液系统的形成。热液系统影响水质并削弱上覆岩石，进一步增加发生重大山体滑坡的可能性。更大规模的火山喷发可能会影响空中交通，从而扰乱全球经济。其中几起地质灾害发生在 2011 年 12 月智利科东考勒火山大规模喷发期间，火山灰羽流到达包括布宜诺斯艾利斯在内的南美洲大部分地区。自然灾害继续对该地区构成重大风险，因为喷发伴随着岩浆的浅层侵入，在陡峭的建筑物内建立了旺盛的热液系统，并布满了许多大的表面裂缝，表明斜坡不稳定。这种喷发序列、近地表侵入岩及其周围环境提供了一个独特的机会，可以促进我们对这种最近形成的侵入体的成因和当前状态的理解，该侵入体可以作为全球近地表岩浆侵入的模型。该项目的目标是能够评估和了解与入侵相关的自然灾害，特别是由地表过程、热液和岩浆过程之间的相互作用引起的自然灾害。此外，拟议的工作旨在增进我们对火山喷发如何从爆炸行为转变为喷发行为的理解，以及这些转变可能导致浅层侵入的形成。除了通过该项目建立强大的美国-智利合作努力外，该团队还将促进大型社区研究部分，邀请学生参加实地和其他研究活动。俯冲带创建火山弧，这是陡峭地形的动态环境，通过火山、深成和景观过程之间的相互作用而建立和修改。水作为动力相互作用的关键因素，以存在于浅层地下的热液系统的形式和侵蚀过程的形式存在。了解当火山活动在十年时间尺度上从根本上改变地貌时，岩浆热液圈以及地表和水圈如何相互作用仍然是一个重大挑战。拟议的项目以 2011-12 年 Córdon Caulle laccolith 为中心，这是地球上最具活力的景观之一。它的独特之处在于活跃的深成岩和火山区域与浅层地下和地表的交汇。它提供了研究作用于地表岩浆路径、浅层岩浆侵入、水圈和地表交叉点的持续过程的机会。重点将是通过将现有的和新提出的观测与地球物理和地球化学模型相结合，增强有关石岩形成和发育的知识，以确定系统的当前状态并预测其未来的演化。该项目结合了火山学、地球物理学、水地球化学和地貌学的方法。它将为构建和修改近地表入侵的内部和外部过程提供新的见解。它的目的是回答为什么浮力岩浆尽管已经有一条通向地表的开放路径，但仍横向侵入地表数百米范围内。除了探索虫石成因之外，该项目还试图通过整合对侵入体内外的结构、质量和热通量以及受内部和外部过程调节的表面演化的广泛现有和新提出的观测结果，为评估其当前状态和未来演化提供基础。该项目将促进国际合作，加强美国和智利之间的科学关系。该项目将采用开放式结构，通过实地学校部分积极扩大研究该火山系统的科学界。外展部分将涉及直接受地区火山影响的农村中学。该项目由地球科学前沿研究 (FRES) 和刺激竞争研究既定计划 (EPSCoR) 联合资助。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

Volcanic landscapes pose a variety of natural hazards to local and regional communities, including volcanic explosions and outpouring of lava, large-scale land sliding of resulting steep terrains, and the formation of shallow hydrothermal systems. The hydrothermal systems affect water quality and weaken the overlying rocks further increasing the likelihood of major landslides. Larger volcanic eruptions may impact air traffic and therefore disrupt the global economy. Several of these geohazards occurred during the large 2011-12 eruption of Cordón Caulle, Chile, with its volcanic ash plume reaching large parts of South America including Buenos Aires. The natural hazards continue to pose a major risk for the region, because the eruption was accompanied by a shallow intrusion of magma that has established a vigorous hydrothermal system within a steep edifice scarred by numerous large surface cracks, indicative of slope instability. This eruption sequence, the near-surface intrusion, and its surroundings present a unique opportunity to advance our understanding of the genesis and current state of this recently formed intrusion, which serves as a model for near-surface magmatic intrusions globally. The goal of this project is ability to evaluate and understand the natural hazards associated with intrusions, in particular those arising from the interactions between surface processes, hydrothermal, and magmatic processes. Furthermore, the proposed work aims to advance our understanding of how volcanic eruptions transition from explosive to effusive behavior and these transitions may lead to the formation of shallow intrusions. In addition to building a strong US-Chilean collaborative effort with this project, the team will facilitate a large community-research component, where students will be invited to participate in field and other research activities.Subduction zones create volcanic arcs that are dynamic environments of steep terrain built and modified by the interplay between volcanic, plutonic, and landscape processes. Water acts as the key agent for dynamical interactions, in the form of the hydrothermal system that exists in the shallow subsurface and in the form of erosional processes. Understanding of how the magmatic-hydrothermal sphere and surface- and hydrosphere interact when volcanic activity fundamentally alters the landscape on decadal time scales remains a major challenge. The proposed project is centered around the 2011-12 Córdon Caulle laccolith, one of the most dynamic landscapes on Earth. It is unique because of the intersection of an active plutonic and volcanic realm with the shallow subsurface and surface. It affords the opportunity to study ongoing processes that act at the intersection of magma pathways to the surface, shallow magma intrusion, hydrosphere, and surface. The focus will be on enhancing knowledge about laccolith initiation and development through the integration of existing and newly proposed observations with geophysical and geochemical models, in order to ascertain the current state of the system and project its future evolution. The project combines methods of volcanology, geophysics, aqueous geochemistry, and geomorphology. It will add new insight into the internal and external processes that build and modify near-surface intrusions. It aims to answer why buoyant magma, despite having already an open path to the surface, intruded laterally within hundreds of meters of the surface. Beyond exploration of laccolith genesis, the project seeks to provide a basis for assessing its current state and future evolution through the integration of a wide range of existing and newly proposed observations of structure, mass and heat flux in and out of the intrusion, and its surface evolution as modulated by the interior and exterior processes. The project will foster international collaborations that strengthen scientific relationships between the US and Chile. The project will have an open structure that actively broadens the science community working on this volcanic system via a field school component. An outreach component will involve rural middle schools that are directly affected by regional volcanism. This project is jointly funded by Frontier Research in Earth Sciences (FRES) and the Established Program to Stimulate Competitive Research (EPSCoR).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.