Towards improved forecasting of volcanic explosivity: Investigating the role of magma mixing

改进火山爆发预测：研究岩浆混合的作用

• 批准号: NE/N014286/1
• 负责人: Michael Cassidy
• 金额: $ 70.37万
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FN014286%2F1
• 关键词: Towards; improved; forecasting; volcanic; explosivity

10% of the world's population live within 100 km of a volcano. With the world's increasing population and stress on natural resources, volcanoes threaten more lives every day. Explosive volcanic eruptions can have devastating societal impacts on nearby populations, covering entire countries in ash, ruining crops and livestock, and cause a huge loss of human life. These eruptions can also have global effects, with the potential to impact air traffic, air quality and surface temperature. Conversely, lava flow or dome-forming (effusive) eruptions are generally less hazardous, with impacts more localised in the area immediately surrounding the volcano. The problem is that any one volcano can erupt both explosively and effusively with rapid changes in eruptive style. We currently do not understand what controls volcano eruptive style. This gap in our knowledge makes the impacts from an impending volcanic eruption very difficult to predict. For instance, with the small, but extremely disruptive explosive eruption of Eyjafjallajokull (Iceland) in 2010, while volcanologists could forecast that an eruption would occur within a few weeks, they were unable to forecast whether the impending eruption would be explosive or effusive. The ability to forecast what type of eruption will occur and how big an eruption will be would help to limit the loss of human life and reduce economic impacts by informing mitigation procedures such as evacuations. Unfortunately this goal cannot be achieved until we can determine what controls an eruption's 'explosive potential'. Most studies believe that shallow processes (<3 km) within the conduit (the magma feeder pipe) govern this transition, however recent work has suggested that deep processes (4-10 km) occurring whilst the magma is in storage (inside the magma chamber) may be key. A particularly important process is when two magmas with different temperatures and chemistries mix at depth, which occurs commonly before eruptions. The gas dissolved in a magma has a big part to play in this process, much like opening a bottle of coke once it has been shaken, but the problem is that we do not know how dissolved gasses behave as a result of magma mixing. This project will take advantage of recent analytical advances in this field. These new techniques will be applied to samples from key eruptions to understand how the dissolved gases reacted when mixed with different magmas and on what timescales these processes occurred before the eruption. The timing is critical, because if magma mixing processes can be detected by scientists monitoring a volcano (with earthquakes for example) then we may be able to forecast what type of eruption will occur based on the data from this study. Alongside this, we will also use high pressure and temperature experiments to recreate the conditions that occur before both our example effusive and explosive eruptions. This project will transform our understanding of what conditions promote more explosive eruptions. Combining the information from this study with monitoring data will help to limit the loss of life and economic damage that explosive eruptions cause.

世界上 10% 的人口居住在距火山 100 公里范围内。随着世界人口的不断增加和自然资源的压力，火山每天都威胁着更多的生命。火山喷发可能对附近人口造成毁灭性的社会影响，火山灰覆盖整个国家，毁坏农作物和牲畜，并造成巨大的人员伤亡。这些喷发还会产生全球影响，有可能影响空中交通、空气质量和地表温度。相反，熔岩流或圆顶形成（喷发）喷发通常危害较小，影响更集中在火山周围的区域。问题是任何一座火山都可能爆发性喷发和喷发式喷发，而且喷发方式会迅速变化。我们目前不了解是什么控制着火山喷发方式。我们知识上的差距使得即将发生的火山喷发的影响很难预测。例如，2010 年埃亚菲亚德拉冰盖（冰岛）发生了规模虽小但破坏性极大的爆炸性喷发，虽然火山学家可以预测几周内会发生喷发，但他们无法预测即将发生的喷发是爆炸性喷发还是溢流喷发。预测将发生什么类型的火山喷发以及火山喷发的规模有多大的能力将有助于限制人员伤亡，并通过通知疏散等缓解程序来减少经济影响。不幸的是，只有我们能够确定是什么控制着火山喷发的“爆炸潜力”，这个目标才能实现。大多数研究认为，管道（岩浆供给管）内的浅层过程（<3公里）控制着这种转变，但最近的研究表明，岩浆储存（岩浆室内）时发生的深层过程（4-10公里） ）可能是关键。一个特别重要的过程是两种具有不同温度和化学成分的岩浆在深处混合，这通常发生在喷发之前。溶解在岩浆中的气体在这个过程中发挥着重要作用，就像摇动一瓶可乐一样，但问题是我们不知道溶解的气体在岩浆混合中的表现如何。该项目将利用该领域最新的分析进展。这些新技术将应用于关键喷发的样本，以了解溶解的气体与不同岩浆混合时如何反应，以及这些过程在喷发前发生的时间尺度。时机至关重要，因为如果监测火山（例如地震）的科学家能够检测到岩浆混合过程，那么我们也许能够根据这项研究的数据预测将会发生什么类型的喷发。除此之外，我们还将使用高压和高温实验来重现我们的示例中的喷发和爆炸性喷发之前发生的条件。该项目将改变我们对哪些条件会引发更多爆炸性喷发的理解。将这项研究的信息与监测数据相结合将有助于限制爆炸性喷发造成的生命损失和经济损失。

项目成果

Explosive Eruptions With Little Warning: Experimental Petrology and Volcano Monitoring Observations From the 2014 Eruption of Kelud, Indonesia

几乎没有任何预警的爆炸性喷发：2014 年印度尼西亚 Kelud 火山喷发的实验岩石学和火山监测观测

• DOI: 10.1029/2018gc008161
• 发表时间: 2019
• 期刊: Geochemistry, Geophysics, Geosystems
• 作者: Cassidy M

Quantifying Microstructural Evolution in Moving Magma

• DOI: 10.3389/feart.2020.00287
• 发表时间: 2020-09-21
• 期刊: FRONTIERS IN EARTH SCIENCE
• 影响因子: 2.9
• 作者: Dobson, Katherine J.;Allabar, Anja;Wanelik, Kaz
• 通讯作者: Wanelik, Kaz

The Ethics of Volcano Geoengineering

火山地球工程的伦理

• DOI: 10.1029/2023ef003714
• 发表时间: 2023
• 期刊: Earth's Future
• 作者: Cassidy M

Controls on explosive-effusive volcanic eruption styles.

• DOI: 10.1038/s41467-018-05293-3
• 发表时间: 2018-07-19
• 期刊: Nature communications
• 影响因子: 16.6
• 作者: Cassidy M;Manga M;Cashman K;Bachmann O
• 通讯作者: Bachmann O

Explosive eruptions with little warning: Experimental petrology and geodetic observations from the 2014 eruption of Kelud, Indonesia

几乎没有任何预警的爆炸性喷发：2014 年印度尼西亚 Kelud 喷发的实验岩石学和大地测量观测

• DOI: 10.31223/osf.io/b4ma8
• 发表时间: 2018
• 作者: Cassidy M