Rheology for near real time forecasting of lava flows

用于熔岩流近实时预测的流变学

• 批准号: 2223098
• 负责人: Stephan Kolzenburg
• 金额: $ 41.06万
• 依托单位: SUNY at Buffalo
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-02-01 至 2026-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2223098&HistoricalAwards=false
• 关键词: Rheology; near; real; time; forecasting

Effective civil protection during effusive volcanic eruptions relies on accurate assessment of three main questions: 1. Where is the eruptive vent? 2. What areas will the lava flows affect? and 3. How fast will lava reach certain areas? Forecasting methods for lava flow paths and velocities require a detailed understanding of the lava’s flow properties (i.e. how viscous it is), the slope of the ground that the lava is flowing on and how much lava is erupted over a certain time interval. As lava flows down a volcano, it cools, crystallizes, and forms and/or loses bubbles, all of which affect how fast and how far lava may flow. An incomplete understanding of how the lava’s flow properties change makes accurate lava flow forecasting, and with that, hazard mitigation ahead of effusive eruptions, civil protection, and management of ongoing eruptive events, difficult. This project is motivated by 1) an incomplete understanding of lava flow properties, 2) a lack of integration of accurate flow properties in lava flow models and 3) the need for shorter response times between eruption onset and availability of lava flow-path forecasts. The project will tackle these challenges using the two most hazardous effusive volcanoes in the world, Nyiragongo and Nyamulagira as type localities. As an example, the 2021 eruption of Nyiragongo claimed over 30 lives, left 20,000 homeless, destroyed 3,500 houses, 12 schools, and 3 hospitals – a powerful expression of the impact lava flows can have on human lives. The core objectives are to 1) reconstruct the lava’s flow properties from natural samples 2) measure the lava’s viscosity at conditions relevant to its emplacement, and 3) integrate these data into a framework of satellite informed lava forecasting models. This may enable the development of a satellite-data-driven near-real time protocol for rapid and accurate forecasting of lava flow paths, which can then be applied during effusive eruptions to help guide decision making in civil protection efforts. Project results will also be incorporated into the SUNY Buffalo EarthEd program, providing content for K12 educators serving underrepresented communities, promoting science literacy. The project will support a graduate student at SUNY Buffalo and involves international collaborations (USA, Italy, France, DR Congo) in academia, development aid, and at volcano observatories.Lava rheology varies as a function of temperature, melt composition, crystal, and bubble content as well as strain rate. From eruption to flow cessation, basaltic lavas traverse a range of up to 10 orders of magnitude in their effective viscosity. The resulting non-linear changes in the lava’s transport behaviour determine how it accommodates deformation during emplacement and how fast and how far a lava can flow. The core objectives are to 1) reconstruct the lava’s rheology from natural samples 2) map the lava’s rheology over conditions relevant to their emplacement, and 3) integrate these data into a framework of satellite informed lava emplacement models. Using careful experimental characterization of the lava enables adaptation of a satellite-data-driven near-real time protocol to develop a tool for rapid and accurate forecasting of lava flow emplacement paths. The project will integrate field measurements, textural analysis, and targeted high temperature rheology experiments to generate the first complete rheological flow law for a basaltic lava that is derived from measurements at conditions relevant to lava emplacement and validated with field constraints. Using this flow law, the project will optimize a lava flow emplacement model, and integrate it into an existing near real time satellite monitoring system. This will create a highly adaptable tool for predicting lava flow paths and advance rates that is rooted in and optimized for the core physical property – lava rheology. The project sets out to: 1) Perform detailed petrographic analyses of natural samples and collect and evaluate field data of lava flow geometries 2) Use these in concert with viscosity measurements in controlled atmospheres to reconstruct the lava’s rheology during emplacement. This includes generating critical new data at reduced conditions, which are extremely scarce. 3) Employ the derived data to initialize and calibrate a deterministic lava flow model. This tool may enable near real time lava emplacement forecasting during future eruptions as well as forensic investigations of previous eruptions. The selected type localities enable testing both cooling- and volume-limited lava emplacement scenarios.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.

火山喷发期间的有效民事保护取决于对三个主要问题的准确评估：1. 喷发口在哪里？ 2. 熔岩流将影响哪些区域？ 3. 熔岩到达某些区域的预测方法？熔岩流动路径和速度需要详细了解熔岩的流动特性（即熔岩的粘度）、熔岩流动的地面坡度以及熔岩流动的程度熔岩在一定的时间间隔内喷发，当熔岩流下火山时，它会冷却、结晶、形成和/或失去气泡，所有这些都会影响熔岩流动的速度和距离。属性变化使得准确的熔岩流预测变得困难，因此，在喷发前减轻灾害、进行民防和管理正在进行的喷发事件变得困难，该项目的动机是 1) 对熔岩的不完全了解。流动特性，2）熔岩流模型中缺乏准确的流动特性的整合，3）需要缩短喷发开始和熔岩流动路径预测之间的响应时间。该项目将使用两种最危险的喷流来应对这些挑战。以尼拉贡戈火山和尼亚穆拉吉拉火山为例，2021 年尼拉贡戈火山喷发夺去了 30 多人的生命，导致 20,000 人无家可归。摧毁了 3,500 所房屋、12 所学校和 3 家医院——有力地体现了熔岩流对人类生活的影响。核心目标是 1) 从自然样本中重建熔岩的流动特性 2) 测量熔岩在相关条件下的粘度。 3）将这些数据整合到卫星通知的熔岩预测模型框架中，这可能有助于开发卫星数据驱动的近实时协议，以快速准确地预测熔岩。熔岩流动路径，然后可以在喷发期间应用，以帮助指导民防工作的决策。项目结果也将纳入纽约州立大学布法罗地球教育计划，为服务于代表性不足的社区的 K12 教育工作者提供内容，提高科学素养。将支持纽约州立大学布法罗分校的一名研究生，并涉及学术界、发展援助和火山观测站的国际合作（美国、意大利、法国、刚果民主共和国）。熔岩流变学随温度、熔体的变化而变化从喷发到停止流动，玄武岩熔岩的有效粘度会经历高达 10 个数量级的范围，由此产生的熔岩传输行为的非线性变化决定了熔岩的传输行为。适应就位过程中的变形以及熔岩流动的速度和距离。核心目标是 1) 从自然样本中重建熔岩的流变学 2) 绘制熔岩的流变图。与它们的安置相关的条件的流变学，以及3）将这些数据整合到卫星通知的熔岩安置模型的框架中，使用熔岩的仔细实验表征可以适应卫星数据驱动的近实时协议来开发工具。该项目将整合现场测量、结构分析和有针对性的高温流变学实验，以生成第一个完整的玄武岩熔岩流变流动定律，该定律是根据相关条件的测量得出的。利用该流动定律，该项目将优化熔岩流就位模型，并将其集成到现有的近实时卫星监测系统中，这将创建一个高度适应性的工具，用于预测熔岩流路径和推进。植根于熔岩流变学并针对其进行优化的速率 该项目旨在： 1) 对自然样本进行详细的岩相分析，并收集和评估熔岩流几何形状的现场数据 2) 将这些数据与熔岩流几何学相结合使用。在受控气氛中进行粘度测量，以重建熔岩在安置过程中的流变学，这包括在还原条件下生成极其稀缺的关键新数据。 3) 利用导出的数据来初始化和校准确定性熔岩流模型。未来喷发期间的时间熔岩埋置预测以及对先前喷发的法医调查可以测试冷却和体积限制的熔岩埋置场景。该奖项反映了这一点。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，NSF 的法定使命被认为值得支持。