NSFGEO-NERC Quantifying disequilibrium processes in basaltic volcanism (DisEqm)

NSFGEO-NERC 量化玄武岩火山活动中的不平衡过程 (DisEqm)

• 批准号: 1642569
• 负责人: Amanda Clarke
• 金额: $ 32.5万
• 依托单位: Arizona State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1642569&HistoricalAwards=false
• 关键词: NSFGEO; NERC; Quantifying; disequilibrium; processes

Although most basaltic eruptions erupt lava, they can also be explosive. An understanding of what controls the eruptive style will lead to better assessment of hazards, such as those to aviation (explosive ash) and to the environment around the volcano (effusive). Most previous work on the controls of explosive versus effusive eruption assumed that crystals and gas are in equilibrium with the melt as it travels from deep within the Earth. This assumption is faulty, however, because crystals and bubbles grow so fast that they are commonly out of equilibrium. A novel x-ray imaging technique will be used to measure the compositions and growth rates of crystals and bubbles under realistic eruption conditions. The project involves an international team of investigators, each of whom will tackle a different part of this integrative project. The United States investigators will integrate the experimental results into computational models to assess how the magma fragments as it is erupting and how ash is transported in the atmosphere.NSF funding is being provided to U.S. investigators who are part of an international team that will assess the importance of disequilibrium processes during basaltic eruptions. X-ray tomography will be performed on decompressing and cooling natural magmas using a diamond light source synchrotron. These measurements will quantify the growth rates, distribution, and compositions of crystal, gas, and melt phases under conditions that are close to those of a natural eruption. The role of the U.S. investigator is to incorporate these parameters into a computational code that simulates magma transport through an eruptive conduit. The truly novel aspect is that previous models assume equilibrium between the phases, but the measurements made as part of this project will provide the necessary parameters to model disequilibrium bubble and crystal growth. The conduit model will then be coupled to a model of an atmospheric eruptive column. These models predict textures and modal contents of the eruptive products, as well as the deposits' distributions, permitting field tests of the numerical models.

尽管大多数玄武岩喷发都会喷出熔岩，但它们也可能具有爆炸性。 了解控制喷发方式的因素将有助于更好地评估危害，例如对航空（爆炸性火山灰）和火山周围环境（喷发）的危害。先前大多数关于控制爆炸性喷发与喷发性喷发的工作都假设，当熔体从地球深处传播时，晶体和气体与熔体处于平衡状态。然而，这种假设是错误的，因为晶体和气泡生长得如此之快，以至于它们通常会失去平衡。一种新颖的 X 射线成像技术将用于测量真实喷发条件下晶体和气泡的成分和生长速率。该项目涉及一个国际研究团队，每个人都将处理这个综合项目的不同部分。美国研究人员将把实验结果整合到计算模型中，以评估岩浆喷发时如何碎裂以及火山灰如何在大气中传播。国家科学基金会正在向美国研究人员提供资金，他们是一个国际团队的成员，该团队将评估岩浆喷发时的情况。玄武岩喷发期间不平衡过程的重要性。将使用金刚石光源同步加速器对天然岩浆进行减压和冷却，进行 X 射线断层扫描。这些测量将量化在接近自然喷发的条件下晶体、气体和熔体相的生长速率、分布和成分。美国研究人员的作用是将这些参数纳入计算代码中，模拟岩浆通过喷发管道的输送。真正新颖的方面是，以前的模型假设相之间达到平衡，但作为该项目的一部分进行的测量将为模拟不平衡气泡和晶体生长提供必要的参数。然后，管道模型将与大气喷发柱模型耦合。这些模型可以预测喷发产物的结构和模态含量，以及沉积物的分布，从而可以对数值模型进行现场测试。

项目成果

On the eruptive origins of lunar localized pyroclastic deposits

月球局部火山碎屑沉积物的喷发起源

• DOI: 10.1016/j.epsl.2020.116426
• 发表时间: 2020
• 期刊: Earth and Planetary Science Letters
• 影响因子: 5.3
• 作者: Keske, Amber L.;Clarke, Amanda B.;Robinson, Mark S.
• 通讯作者: Robinson, Mark S.

Tecolote volcano, Pinacate volcanic field (Sonora, Mexico): A case of highly explosive basaltic volcanism and shifting eruptive styles

特科洛特火山，皮纳卡特火山田（墨西哥索诺拉）：高爆炸性玄武岩火山活动和不断变化的喷发方式的案例

• DOI: 10.1016/j.jvolgeores.2019.04.011
• 发表时间: 2019
• 期刊: Journal of Volcanology and Geothermal Research
• 影响因子: 2.9
• 作者: Zawacki, Emily E.;Clarke, Amanda B.;Arrowsmith, J. Ramón;Bonadonna, Costanza;Lynch, Daniel J.
• 通讯作者: Lynch, Daniel J.

Conduit dynamics of highly explosive basaltic eruptions: The 1085 CE Sunset Crater sub-Plinian events

高爆炸性玄武岩喷发的管道动力学：公元 1085 年日落陨石坑亚普林尼事件

• DOI: 10.1016/j.jvolgeores.2019.08.001
• 发表时间: 2019
• 期刊: Journal of Volcanology and Geothermal Research
• 影响因子: 2.9
• 作者: La Spina, G.;Clarke, A.B.;de' Michieli Vitturi, M.;Burton, M.;Allison, C.M.;Roggensack, K.;Alfano, F.
• 通讯作者: Alfano, F.

Role of volatiles in highly explosive basaltic eruptions

挥发物在高爆炸性玄武岩喷发中的作用

• DOI: 10.1038/s43247-022-00479-6
• 发表时间: 2022
• 期刊: Communications Earth & Environment
• 影响因子: 7.9
• 作者: La Spina, Giuseppe;Arzilli, Fabio;Burton, Mike R.;Polacci, Margherita;Clarke, Amanda B.
• 通讯作者: Clarke, Amanda B.

Explosivity of basaltic lava fountains is controlled by magma rheology, ascent rate and outgassing

• DOI: 10.1016/j.epsl.2020.116658
• 发表时间: 2021-01-01
• 期刊: EARTH AND PLANETARY SCIENCE LETTERS
• 影响因子: 5.3
• 作者: La Spina, G.;Arzilli, F.;Mader, H. M.
• 通讯作者: Mader, H. M.