Pre-eruptive magma assembly, evolution and associated magma fluxes at arc calderas: insights from the active Cerro Blanco Volcanic Complex, Catamarca, Argentina.

弧火山口喷发前的岩浆聚集、演化和相关岩浆通量：来自阿根廷卡塔马卡活跃的塞罗布兰科火山群的见解。

• 批准号: 2243737
• 负责人: Shanaka de Silva
• 金额: $ 38.03万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-01 至 2026-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2243737&HistoricalAwards=false
• 关键词: Pre; eruptive; magma; assembly; evolution

Explosive volcanic eruptions affect society from local to global scale. Locally and regionally, society and infrastructure may be devastated. Globally, such eruptions can affect global climate. Historic examples include Tambora 1815 and Pinatubo 1991. These eruptions occur at subduction zones, where Earth’s tectonic plates converge. They also form calderas, where the ground above the magma chamber collapses to produce a big depression. Such eruptions have occurred at a frequency of several per century, so they are of concern to society. A key question in the efforts to understand the potential threat from such caldera volcanoes is “how are eruptible bodies of magma assembled and for how long do they persist?”. To answer this question, the project will focus on the currently active Cerro Blanco Volcanic Complex (CBVC) in Catamarca, Argentina. Here, three major explosive eruptions in the last ~30,000 years record the episodic development of an active caldera volcano. The project will reveal the growth, development, and persistence of magma at the CBVC using the chemistry and age of minerals that grew in the magma. The latest approaches to age dating and geochemistry of individual minerals from the eruptions will be used. New ways of analyzing and modeling these data will be developed. The project has many broader impacts that benefit the discipline and society. The senior science team is international and diverse. These senior scientists will mentor a junior scientist from Argentina. An undergraduate researcher will also be deeply involved in this project. The outcomes of this project will support the local tourism industry and be the focus of a future field workshop for volcano scientists.This project will constrain the magmatic processes and fluxes that have assembled and sustained a 30,000-year locus of intense rhyolitic volcanism in the Central Volcanic Zone of the Andes. Two hypotheses relevant to subduction-related caldera volcanoes worldwide will be tested: 1) The magmatic flux that led to the development and evolution of the CBVC is typical of arc-related magmatic fluxes worldwide; and 2) The CBVC is the surface expression of an episodically built composite arc pluton. The first phase of the project will utilize coupled U-series and U-Th/He in zircon (Zircon Double Dating or ZDD) to refine the eruptive frequency and tempo of the CBVC and delineate the spatiotemporal development of the CBVC. This framework will then be used to probe the magmatic evolution, development, and current state of the magmatic complex, directly testing the two hypotheses. To do this, trace elements and O-isotopes in zircon will also be collected and integrated with melt chemistry, rhyolite-MELTS, and thermochemical modeling of zircon ages. The outcomes of the study will include new efforts in thermochemical modeling of these systems that will advance the understanding of how magma is stored pre-eruption in the shallow crust and builds up to catastrophic eruptions of a scale that have occurred in historic times and are therefore of immediate social relevance. This knowledge is also fundamental to how batholiths are constructed, the earth’s crust evolves, and how ore bodies form. The project features international collaborations that provide access to the newest approaches to link age dating and geochemistry of young volcanic systems. A diverse team of senior scientists will mentor an early career researcher from Argentina and undergraduate researchers to ensure that broader impacts of human capital development, knowledge transfer, and research experience for undergraduates are addressed. Outreach to local tourism efforts, and a future field workshop round out the broader impacts.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.

爆炸性火山喷发影响从地方到全球规模的社会。在本地和地区，社会和基础设施可能会遭受毁灭。在全球范围内，这种喷发会影响全球气候。历史性的例子包括Tambora 1815和Pinatubo 1991。这些喷发发生在俯冲带，地球的构造板汇聚。它们还形成了火山口，岩浆腔室上方的地面崩溃了，产生了大萧条。这样的爆发发生在每个世纪的几个频率，因此它们引起了社会的关注。努力了解这种火山火山的潜在威胁的一个关键问题是“岩浆的爆发尸体如何组装，它们持续了多长时间？”。为了回答这个问题，该项目将重点关注目前活跃的阿根廷Catamarca的Cerro Blanco火山综合体（CBVC）。在这里，在过去的〜30，000年中，有三起主要的爆炸性爆发记录了活跃火山火山的情节发展。该项目将使用岩浆中生长的化学和年龄揭示岩浆在CBVC上的生长，发展和持久性。将使用爆发的各个矿物质的年龄约会和地球化学方法。将开发分析和建模这些数据的新方法。该项目具有更广泛的影响，使学科和社会受益。高级科学团队是国际和多样的。这些高级科学家将指导来自阿根廷的初级科学家。本科研究人员也将深入参与该项目。该项目的结果将支持当地的旅游业，并成为火山科学家未来的现场研讨会的重点。该项目将限制岩浆过程和通量，这些过程和通量已经组装并维持了30，000年的当地人在安德斯中央火山区的强烈的节奏火山。将测试与俯冲相关火山火山相关的两个假设：1）导致CBVC的发展和演变的岩浆通量是全球与ARC相关的岩浆磁通量的典型代表； 2）CBVC是情节构建的复合弧岩的表面表达。该项目的第一阶段将利用耦合的U系列和u-th/He在锆石（锆石双重约会或ZDD中）来完善CBVC的爆发频率和速度，并描述CBVC的空间时间发育。然后，该框架将用于探测岩浆复合物的岩浆演化，发育和当前状态，直接测试这两个假设。为此，还将收集锆石中的痕量元素和O-异位素，并与锆石年龄的熔体化学，流纹岩融合和热化学建模进行集成。该研究的结果将包括这些系统的热化学建模方面的新努力，这些努力将提高人们对岩浆在浅层壳中的爆发方式的理解，并建立在历史性时期发生的量表的灾难性爆发，因此具有直接的社会相关性。这些知识也是bassoliths的建造方式，地球的地壳演变以及矿石的形成方式的基础。该项目以国际合作为特色，可访问最新的方法，以链接年龄约会和年轻火山系统的地球化学。一个高级科学家的潜水团队将指导来自阿根廷和本科研究人员的早期职业研究员，以确保对人力资本发展，知识转移和研究经验的影响。向当地旅游努力以及未来的实地研讨会揭开展览，这会弥补更广泛的影响。该奖项反映了NSF的法定任务，并通过使用基金会的知识分子优点和更广泛的影响评估标准来评估值得支持。