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

火山景观对当地和区域社区构成各种自然灾害，包括火山爆发和熔岩涌出、由此产生的陡峭地形的大规模陆地滑动以及浅层热液系统的形成。热液系统影响水质，削弱上覆岩石，进一步增加了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。其中一些地质灾害发生在2011-12年智利科隆火山大规模喷发期间，其火山灰羽流到达包括布宜诺斯艾利斯在内的南美洲大片地区。自然灾害继续对该区域构成重大风险，因为火山喷发伴随着浅层岩浆侵入，在一座陡峭的建筑物内建立了强有力的热液系统，建筑物上留下了许多巨大的表面裂缝，表明斜坡不稳定。这一喷发序列、近地表侵入体及其周围环境为我们提供了一个独特的机会来促进我们对这一新形成的侵入体的成因和现状的理解，它是全球近地表岩浆侵入的模式。该项目的目标是能够评估和了解与侵入有关的自然灾害，特别是由地表过程、热液作用和岩浆作用之间的相互作用引起的自然灾害。此外，拟议的工作旨在促进我们对火山喷发如何从爆炸行为转变为热流行为以及这些转变可能导致浅层侵入形成的理解。除了与该项目建立强大的美国和智利的合作努力外，该团队还将促进一个大型社区研究部分，在那里学生将被邀请参加野外和其他研究活动。俯冲带形成火山弧，这是通过火山、深成和景观过程之间的相互作用建立和修改的陡峭地形的动态环境。水作为动力相互作用的关键因素，以水热系统的形式存在于浅层地下，并以侵蚀过程的形式存在。当火山活动在十年时间尺度上从根本上改变地貌时，理解岩浆-热液圈层与地表-水圈如何相互作用仍然是一个重大挑战。拟议的项目围绕2011-12年的Córdon Caulle岩层展开，这是地球上最具活力的景观之一。它是独一无二的，因为活跃的深成岩和火山岩领域与浅层地下和地表相交。它为研究在通往地表、浅层岩浆侵入、水圈和地表的岩浆路径交汇处进行的过程提供了机会。重点将是通过将现有和新提议的观测与地球物理和地球化学模型相结合，加强对岩浆形成和发展的了解，以确定该系统的当前状态，并预测其未来的演变。该项目结合了火山学、地球物理学、水化学和地貌学的方法。它将增加对建立和修改近地表侵入的内部和外部过程的新见解。它的目的是回答为什么浮力岩浆，尽管已经有一条通往地表的开放路径，却在距离地表数百米的范围内横向侵入。除了探索岩屑成因外，该项目还试图通过整合现有和新提出的对侵入体内外的结构、质量和热通量的广泛观测，以及其受内部和外部过程调制的表面演化，为评估其现状和未来的演化提供基础。该项目将促进国际合作，加强美国和智利之间的科学关系。该项目将有一个开放的结构，通过实地学校的组成部分，积极扩大研究这一火山系统的科学界。外展部分将涉及直接受到区域火山活动影响的农村中学。该项目由地球科学前沿研究(FRES)和已建立的激励竞争性研究计划(EPSCoR)共同资助。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势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.