Dynamic triggering and criticality: earthquake interactions during unrest at Sierra Negra volcano, Galapagos Islands

动态触发和临界性：加拉帕戈斯群岛内格拉火山动荡期间的地震相互作用

• 批准号: NE/S002685/1
• 负责人: Andrew Bell
• 金额: $ 6.43万
• 依托单位: University of Edinburgh
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FS002685%2F1
• 关键词: Dynamic; triggering; criticality; earthquake; interactions

Observations across many earthquake fault systems and volcanoes tell us that the small changes in stress due to large earthquakes can trigger other large earthquakes or volcanic eruptions. In a recent example, these interactions underpinned the sequence of large destructive earthquakes in central Italy in 2016. The lack of current understanding of the susceptibility of certain faults and volcanoes to small stress changes and the nature of these interactions are some of the key unknowns hampering our ability to forecast future large earthquakes and eruptions. Opportunities to study these interactions, with high quality data over many repeated triggering events, are valuable, but extremely rare.Sierra Negra volcano in the Galapagos Islands is currently showing considerable signs of unrest, due to the arrival of new magma at shallow levels. New observations in January 2018 show that the unrest has made the volcano particularly and unusually susceptible to remote earthquake triggering. The tiny low frequency shaking associated with large earthquakes many 1000s of kilometres away is triggering small high frequency earthquakes in the volcano. The high rate of large earthquakes along the Pacific coast of the Americas provides frequent triggering events, and preliminary analysis suggests that rapid deployment of a high resolution seismic network might expect to record many tens of triggering episodes in the next year. Sierra Negra is presenting a superb, but short-term, 'natural laboratory' to study earthquake-earthquake and earthquake-volcano critical triggering.This project will deploy a high-density network of seismometers at Sierra Negra for 12 months for record the seismic activity taking place at the volcano. These data will allow us to determine when, where, and how earthquake triggering is taking place, and provide important new information about the factors that control the response of 'critically-stressed' geological systems. In addition, the data will allow us to follow the evolution of volcanic unrest, and the seismic signals associated with any eruptive activity that occurs during deployment.

对许多地震断层系统和火山的观测告诉我们，大地震引起的应力的微小变化可能会引发其他大地震或火山喷发。在最近的一个例子中，这些相互作用支撑了 2016 年意大利中部发生的一系列大规模破坏性地震。目前对某些断层和火山对小应力变化的敏感性以及这些相互作用的性质缺乏了解，是阻碍地震发生的一些关键未知因素。我们预测未来大地震和火山爆发的能力。利用许多重复触发事件的高质量数据来研究这些相互作用的机会是有价值的，但极其罕见。由于新岩浆到达浅层，加拉帕戈斯群岛的内格拉火山目前显示出相当大的动荡迹象。 2018 年 1 月的新观测结果表明，动乱使这座火山特别且异常容易受到远程地震的影响。与数千公里外的大地震相关的微小低频震动正在引发火山中的小型高频地震。美洲太平洋沿岸大地震发生率高，触发事件频繁，初步分析表明，快速部署高分辨率地震台网有望在明年记录数十次触发事件。内格拉山脉正在展示一个一流但短期的“自然实验室”，用于研究地震-地震和地震-火山临界触发。该项目将在内格拉山脉部署一个高密度地震仪网络，为期 12 个月，以记录地震活动发生在火山。这些数据将使我们能够确定地震触发的时间、地点和方式，并提供有关控制“临界应力”地质系统响应的因素的重要新信息。此外，这些数据将使我们能够跟踪火山动荡的演变，以及与部署期间发生的任何喷发活动相关的地震信号。

项目成果

Magmatic connectivity among six Galápagos volcanoes revealed by satellite geodesy.

• DOI: 10.1038/s41467-023-42157-x
• 发表时间: 2023-10-19
• 期刊: NATURE COMMUNICATIONS
• 影响因子: 16.6
• 作者: Reddin, Eoin;Ebmeier, Susanna K.;Rivalta, Eleonora;Bagnardi, Marco;Baker, Scott;Bell, Andrew F.;Mothes, Patricia;Aguaiza, Santiago
• 通讯作者: Aguaiza, Santiago

Seismic tremor reveals slow fracture propagation prior to the 2018 eruption at Sierra Negra volcano, Galápagos

地震揭示了加拉帕戈斯群岛内格拉火山 2018 年喷发前的缓慢裂缝传播

• DOI: 10.1016/j.epsl.2022.117533
• 发表时间: 2022
• 期刊: Earth and Planetary Science Letters
• 影响因子: 5.3
• 作者: Li K

Caldera resurgence during the 2018 eruption of Sierra Negra volcano, Galápagos Islands.

• DOI: 10.1038/s41467-021-21596-4
• 发表时间: 2021-03-02
• 期刊: Nature communications
• 影响因子: 16.6
• 作者: Bell AF;La Femina PC;Ruiz M;Amelung F;Bagnardi M;Bean CJ;Bernard B;Ebinger C;Gleeson M;Grannell J;Hernandez S;Higgins M;Liorzou C;Lundgren P;Meier NJ;Möllhoff M;Oliva SJ;Ruiz AG;Stock MJ
• 通讯作者: Stock MJ

Dynamic earthquake triggering response tracks evolving unrest at Sierra Negra volcano, Galápagos Islands.

• DOI: 10.1126/sciadv.abh0894
• 发表时间: 2021-09-24
• 期刊: Science advances
• 影响因子: 13.6
• 作者: Bell AF;Hernandez S;McCloskey J;Ruiz M;LaFemina PC;Bean CJ;Möllhoff M
• 通讯作者: Möllhoff M