Collaborative Research: BENEATH THE FOUNTAINS: Shallow conduit processes and diversity in basaltic fissure eruptions.

温和的爆发性火山喷发是地球上陆上爆发性火山活动最常见的表现形式，大致分为两种类型：斯特龙博利式和夏威夷式。前者的特点是间歇性的离散爆炸序列，后者的持续火山碎屑喷泉。2018年Kamplauea火山（Hawai Kamplauea）裂缝喷发期间的爆炸活动提供了一个难得的机会来记录各种Strombolian和夏威夷行为（图1），这要归功于火山的可访问性和整个事件中收集的丰富数据类型。这项研究解决了火山下方管道系统中的哪些过程“驱动”了2018年爆炸活动的风格和强度的巨大多样性，而不是之前在Kallauea和其他地方发生的更一致的裂缝喷发？克基拉岛是一座异常活跃的火山，其喷发给管理机构带来了持续的挑战，因为喷发地点非常容易进入，并且需要平衡公众对观看喷发活动的强烈兴趣与公共安全（如2018年所见）。这种平衡需要对火山目前和即将到来的未来行为的复杂知识。公众既希望更好地了解火山的行为，也需要更好地预测未来所有火山爆发的可能过程和足迹。天文台的合作伙伴美国地质勘探局（USGS）在联邦政府的授权下，为夏威夷的应急机构提供建议，并将把NSF资助的研究中的知识转移给负责风险管理的机构。这项工作涉及美国和联合王国的机构之间的材料和思想交流，以使年轻的研究人员和学生受益。研究结果将通过会议和讲习班、由FEMA资助的国家备灾培训中心提供的课程、因特网和科学出版物以及计划中的基拉韦厄虚拟实地考察等方式广泛传播，这项研究的目标是将现有的玄武岩裂缝爆炸性喷发的高分辨率观测结果与引起和形成这些喷发的非常浅的管道中的过程联系起来，以2018年的Kampallauea火山喷发为例进行研究。它将把来自高时空分辨率视频的现有数据与以下内容结合起来：（1）五个代表性火山碎屑足迹的现场测量，以及喷出物的实验室表征，（2）两相岩浆流变学的高精度测量，以及（3）与新完成的实验室模拟实验相关联的模型，以模拟放气模式。预计这种方法将有助于确定伴随着喷发方式转变的模式和前兆，为这座非常活跃的火山侧翼社区的风险管理提供支持。这项研究将从根本上提高我们对夏威夷和斯特龙博利火山爆发的动力学的理解。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。

Mildly explosive eruptions—the most frequent manifestations of subaerial explosive volcanism on Earth—broadly group into two styles: Strombolian and Hawaiian. The former is characterized by sequences of intermittent discrete explosions and the latter by sustained pyroclastic fountaining. Explosive activity during the 2018 fissure eruption of Kīlauea volcano (Hawaiʻi) provided an exceptional opportunity to record a wide range of Strombolian and Hawaiian behavior (Figure 1), thanks to the accessibility of the volcano and the wealth of data types collected throughout the event. This study address which processes in the plumbing system beneath the volcano ‘drove’ the great diversity in style and intensity of the 2018 explosive activity compared to previous, more consistent, fissure eruptions at Kīlauea and elsewhere? Kīlauea is an exceptionally active volcano and its eruptions pose constant challenges for management agencies because the eruption sites are highly accessible and there is a need to balance the strong popular interest in viewing the eruptive activity against public safety (as seen in 2018). This balance requires critically on sophisticated knowledge of the volcano’s current and immediately future behavior. There is both a public desire for better knowledge of the volcano’s behavior and a need for improved forecasting of the likely course and footprint of all future eruptions. The observatory partner, USGS, has a federally mandated role to advise response agencies in Hawaii and will transfer knowledge from the NSF-funded study to the bodies charged with risk management. This work involves exchange of material and ideas between institutions in the USA, and the United Kingdom to the benefit of young researchers and students. The results will be widely disseminated via meetings and workshops, courses offered by the FEMA-funded National Disaster Preparedness Training Center, the Internet and scientific publications and a planned virtual field trip to Kilauea.The goal of this study is to link existing high-resolution observations of explosive basaltic fissure eruptions to the processes in the very shallow conduit that cause and shape them, focusing on the 2018 Kīlauea eruption as a case study. It will combine existing data derived from high temporal and spatial resolution videos with: (1) field measurements of five representative pyroclastic footprints, and laboratory characterization of the ejecta, (2) high-precision measurements of two-phase magma rheology, and (3) models tied to newly completed laboratory analog experiments to simulate outgassing patterns. This approach is expected to help identify patterns and precursors that accompany transitions in eruptive style, supporting risk management for communities on the flank of this very active volcano. This study will fundamentally improve our understanding of the dynamics of Hawaiian and Strombolian eruptions.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.