RAPID: Deployment of a Field Rheometer Prototype

RAPID：现场流变仪原型的部署

• 批准号: 2241489
• 负责人: Stephan Kolzenburg
• 金额: $ 5.26万
• 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: 2022
• 资助国家: 美国
• 起止时间: 2022-08-15 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2241489&HistoricalAwards=false
• 关键词: RAPID; Deployment; Field; Rheometer; Prototype

This project deploys a field rheometer prototype to the reawakened eruption at Geldingadalir Volcano, Iceland with the goal to test its field performance and to gather the first ever rheological data on active Icelandic Mid Ocean Ridge Basalts (MORB) in the field. Access to active lava flows is challenging due to the unpredictable nature of the timing and occurrence of effusive eruptions. This eruption, which started August 3, 2022, provides unparalleled ease of access to active lava flows whose nature is sufficiently “well behaved” to facilitate in-situ measurements of lava properties. This project strives to achieve two fundamental goals: 1) Travel to Iceland to deploy the field rheometer prototype to collect the first field measurements with this device and test its limits. 2) Performing a series of two-phase (melt+crystals) experiments at the temperatures, shear rates, and fO2 of lava measured at Geldingadalir Volcano. Combined, this enables this team to collect the first field measurements of the rheology of Icelandic MORB lavas and to deduce the effect of bubbles on three-phase rheology by contrasting the field measurements (with bubbles) and lab measurements (bubble-free). InSAR data published by the Icelandic Meteorological Office suggest higher magma influx rates for this eruption than for the 2021 eruption. This could mean either that the eruption lasts longer than that of 2021 or it could mean that much of the available lava is erupted through the pathway created during the previous eruptive event over a short period of time. Accurate forecasting of lava flow paths and advance rates is crucial to hazard mitigation ahead of and during effusive events, civil protection, and management of ongoing eruptive crises. This task has been hampered largely by an incomplete understanding of multiphase (melt+crystals+bubbles) lava rheology. Field viscosity measurements are extremely rare and largely limited to a narrow compositional range (dominated by Hawaiian Basalts). This highlights the dire need for more, and better in-situ measurements on a broader range of compositions. While our understanding of the flow properties of lavas has advanced significantly over the past two to three decades, two core limitations have always remained: 1) Accurate reproduction of natural emplacement conditions (scale, textures, fO2) 2) The inability to maintain three-phase suspensions in the lab (bubbles escape on experimental timescale, limiting measurements to two-phase crystals-melt suspensions). Measuring the viscosity of lava in the field removes both limitations. Importantly, when combined with bubble free lab measurements it has the potential to quantify the effect of bubbles on multiphase lava rheology. This project therefore has the potential to address some of the major limiting factors to advancing our understanding of lava flow emplacement for decades. Results will be shared with stakeholders within and beyond the scientific community, and some samples and tools from this work will be incorportated into the Buffalo Museum of Science. Project insights will also be incorporated into hands on exercises in the UB EarthEd program, providing content for K12 educators.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.

该项目将现场流变仪原型部署到冰岛盖尔丁达利尔火山重新喷发的地方，目的是测试其现场性能，并收集有关现场活跃的冰岛中洋脊玄武岩 (MORB) 的首个流变数据。由于喷发的时间和发生的不可预测性，接近活跃的熔岩流具有挑战性。这次喷发于 2022 年 8 月 3 日开始，为接近活跃的熔岩流提供了无与伦比的便利，其性质“表现良好”，有利于熔岩特性的现场测量。该项目致力于实现两个基本目标：1) 前往冰岛部署现场流变仪原型，以收集该设备的首次现场测量结果并测试其极限。 2) 在盖尔丁达利尔火山测量的熔岩温度、剪切速率和 fO2 条件下进行一系列两相（熔体+晶体）实验。结合起来，这使得该团队能够收集冰岛 MORB 熔岩流变学的首次现场测量，并通过对比现场测量（有气泡）和实验室测量（无气泡）来推断气泡对三相流变学的影响。冰岛气象局发布的 InSAR 数据显示，本次喷发的岩浆流入率高于 2021 年的喷发。这可能意味着喷发持续时间比 2021 年更长，或者可能意味着大部分可用熔岩是在短时间内通过上次喷发事件期间形成的通道喷发的。准确预测熔岩流动路径和推进速度对于在喷发事件之前和期间减轻灾害、民事保护和持续喷发危机的管理至关重要。这项任务很大程度上受到对多相（熔体+晶体+气泡）熔岩流变学的不完全理解的阻碍。现场粘度测量极其罕见​​，并且很大程度上局限于狭窄的成分范围（以夏威夷玄武岩为主）。这凸显了对更广泛的成分进行更多、更好的现场测量的迫切需要。虽然我们对熔岩流动特性的理解在过去的两到三十年中取得了显着进展，但始终存在两个核心限制：1）自然安置条件（规模、纹理、fO2）的准确再现2）无法在实验室中维持三相悬浮液（气泡在实验时间尺度上逸出，限制了对两相晶体熔体悬浮液的测量）。在现场测量熔岩的粘度可以消除这两个限制。重要的是，当与无气泡实验室测量相结合时，它有可能量化气泡对多相熔岩流变学的影响。因此，该项目有可能解决一些主要限制因素，以增进我们对熔岩流安置的理解数十年。结果将与科学界内外的利益相关者分享，这项工作的一些样本和工具将被纳入布法罗科学博物馆。项目见解还将纳入 UB EarthEd 计划的实践练习中，为 K12 教育工作者提供内容。该奖项反映了 NSF 的法定使命，并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，被认为值得支持。