NSF/GEO-NERC: Collaborative Research: Multi-scale investigation of rheology and emplacement of multi-phase lava

NSF/GEO-NERC：合作研究：流变学和多相熔岩安置的多尺度研究

• 批准号: 1928923
• 负责人: Alan Whittington
• 金额: $ 34.92万
• 依托单位: University of Texas at San Antonio
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-10-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1928923&HistoricalAwards=false
• 关键词: NSF; GEO; NERC; Collaborative; Research

Lava flows displace communities, destroy homes and infrastructure, and can pose a serious hazard to life and health. Accurate forecasting of lava flow emplacement is essential to hazard mitigation and management, and requires a level of understanding of the physical properties of lava which is not currently available. This project will focus on improving this understanding by examining the 2018 eruption of Kilauea volcano, in Hawai'i. This large eruption took place on the lower east rift zone, and was significant in its large volume, fast speeds, and large fraction of gas bubbles. A unique aspect of this eruption is also the unprecedented volume of high-quality direct observations of in-situ flow, including high-resolution videos of flowing lava collected by drones. The team will use the observations from Hawai'i together with mathematical models of lava flows, analysis of samples collected from the flow, and laboratory experiments utilizing bubbly suspensions, to advance the ability to forecast how volcanic eruptions evolve and mitigate their hazards. In addition, the project will involve educators and students and produce educational materials based on the eruption, to promote science literacy and broaden participation. This is a project that is jointly funded by the National Science Foundation's Directorate of Geosciences (NSF/GEO) and the National Environment Research Council (NERC) of the United Kingdom (UK) via the NSF/GEO-NERC Lead Agency Agreement. This Agreement allows a single joint US/UK proposal to be submitted and peer-reviewed by the Agency whose investigator has the largest proportion of the budget. Upon successful joint determination of an award, each Agency funds the proportion of the budget and the investigators associated with its own country (in this case, Durham University).One of the challenges is that lava is a complex fluid that contains liquid melt, gas bubbles, and solid crystals, all acting together to determine the lava's behavior. This interaction changes during the advancement of the lava as crystals form, bubbles leave and the melt cools. This project will address this challenge by resolving two issues: 1) how multi-phase lava rheology evolves during emplacement; 2) how rheology impacts emplacement. The 2018 eruption at the Lower East Rift Zone of Kilauea Volcano in Hawaii (KLERZ) provides an opportunity to investigate lava emplacement in unprecedented detail. During the eruption, Unoccupied Aerial Systems (UAS) captured a uniquely comprehensive time-series of overhead videos of channelized lava. This study will create a new physical-mathematical framework for predicting lava flow emplacement based on new, quantitative understanding of the coupled evolution of lava rheology. We will leverage unprecedented, linked field data sets and combine them with analog experiments of channelized multi-phase flows and laboratory measurements of natural and analog mutliphase samples to investigate multi-phase rheology and flow at a range of length scales. This team will: 1) Perform laboratory rheometry and microstructure analysis of KLERZ samples; 2) Use UAS data to characterize the evolution of KLERZ channelized flows; 3) Used scaled lava analogues to construct and calibrate fundamental physical models; 4) Synthesize all observations to produce scale-sensitive rheological laws for KLERZ lavas; and 5) Integrate new rheological relations in existing flow emplacement models and test those on KLERZ flow field. The core deliverable of the proposed research will be a validated quantitative framework for predicting lava flow emplacement. This outcome is expected to improve assessment and mitigation of volcanic hazards. In addition, all numerical models and measurements from analog experiments will be made open, so that they can be used as benchmarks for future models. This study will enable scientists and practitioners to determine material properties and flow behavior of the natural system and, conversely, to use field observations of lava emplacement to deduce the properties of the lava.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.

熔岩流使社区流离失所，摧毁房屋和基础设施，并可能对生命和健康构成严重危害。准确预测熔岩流的位置对减灾和管理至关重要，需要对熔岩的物理性质有一定程度的了解，而这是目前无法获得的。该项目将通过研究夏威夷基拉韦厄火山2018年的喷发来提高对这一问题的认识。这次大喷发发生在低东裂谷带，具有体积大、速度快、气泡多的特点。这次火山爆发的一个独特之处是对现场流动进行了前所未有的高质量直接观测，包括无人机收集的流动熔岩的高分辨率视频。该团队将利用夏威夷的观测结果以及熔岩流的数学模型，对从流动中收集的样本进行分析，并利用气泡悬浮液进行实验室实验，以提高预测火山爆发如何演变并减轻其危害的能力。此外，该项目将让教育工作者和学生参与，并根据火山爆发制作教育材料，以促进科学素养和扩大参与。这是一个由国家科学基金会地球科学理事会（NSF/GEO）和联合王国国家环境研究理事会（NERC）通过NSF/GEO-NERC牵头机构协议共同资助的项目。该协议允许美国/英国提交一份联合提案，并由研究者拥有最大预算比例的机构进行同行评审。一旦成功地共同确定了一项奖励，每个机构就会为预算的一部分和与其本国（在本例中是达勒姆大学）有关的调查人员提供资金。挑战之一是熔岩是一种复杂的流体，包含液态熔体、气泡和固态晶体，所有这些共同作用决定了熔岩的行为。这种相互作用在熔岩的前进过程中发生变化，因为晶体形成，气泡离开和熔体冷却。该项目将通过解决两个问题来应对这一挑战：1）多相熔岩流变学如何在侵位过程中演变; 2）流变学如何影响侵位。2018年在夏威夷的基拉韦厄火山（KLERZ）的下东裂谷区的喷发提供了一个前所未有的详细调查熔岩就位的机会。在火山爆发期间，UAS航拍系统（UAS）捕捉到了一个独特的、全面的通道化熔岩头顶视频时间序列。这项研究将建立一个新的物理数学框架，预测熔岩流侵位的基础上新的，定量的了解熔岩流变学的耦合演化。我们将利用前所未有的，链接的现场数据集和联合收割机结合起来，模拟实验的通道化多相流和实验室测量的自然和模拟多相样品，以调查多相流变学和流动在一系列的长度尺度。该小组将：1）对KLERZ样品进行实验室流变测量和微观结构分析; 2）使用UAS数据表征KLERZ通道化流动的演化; 3）使用比例熔岩模拟物构建和校准基本物理模型; 4）综合所有观察结果以产生KLERZ熔岩的比例敏感流变规律;（5）在已有的流位模型中加入新的流变关系，并在KLERZ流场上进行了验证。拟议研究的核心成果将是预测熔岩流就位的有效定量框架。预计这一成果将改善火山灾害的评估和减轻工作。此外，所有数值模型和模拟实验的测量结果都将开放，以便它们可以用作未来模型的基准。这项研究将使科学家和从业人员能够确定自然系统的材料特性和流动行为，反之，利用对熔岩就位的实地观察来推断熔岩的特性。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。

项目成果

Spontaneous reheating of crystallizing lava

结晶熔岩的自发再加热

• DOI: 10.1130/g49148.1
• 发表时间: 2021
• 期刊: Geology
• 影响因子: 5.8
• 作者: Whittington, Alan G.;Sehlke, Alexander
• 通讯作者: Sehlke, Alexander