DV3M: Deforming Volcanoes with Dynamic Magma-Mush Models

背景超过8亿人生活在火山附近，而更多的人依靠火山维持生计。在火山喷发期间保护生命和生计是火山学中的关键挑战，危险评估和喷发预测的不确定性使这一挑战变得更加复杂。可测量的地面变形是用于监测火山的主要工具之一，通常是由于在地表下注入岩浆造成的。通过将形变测量与模型相结合，我们可以估计驱动位移的岩浆供应的位置和速率；这些参数被提供给危险评估和喷发预测。然而，大多数模型都是基于过时的概念，可能会造成所指出的不确定性。它们假定岩浆室是静态的，尽管最近我们对次火山岩浆系统的理解发生了令人兴奋的范式转变，这表明岩浆极有可能储存在垂直分布的多孔带中。根据有限的静态破坏阈值，静态岩浆室也被假设在流体-固体边界处破裂(可能导致喷发)，但在真实情况下，不同的流体-固体边界现在被认为是不太可能的，而且系统本质上是响应岩浆运动而不是静态地动态演化的。因此，在大多数火山变形模型中，人为充气和破坏静态室的简单过程是对现实的重大简化，并将额外的不确定性引入关键的模型输出。我们不知道新的混合范式对火山变形的影响。目的和对象需要DV3M来提出新一代动态岩浆混合(DMM)火山变形模型。DV3M旨在解决多孔岩浆储集层对火山变形和储集层稳定性的影响。项目目标是：1.将岩浆属性纳入随温度和压力而演化的DMM模型。岩浆属性的演化不能用通常使用的静态火山变形模型来解释。DV3M将提供一套DMM火山变形模型，将其与岩浆中随温度和压力变化的变化结合在一起，开发新的计算高效的开源工具。我们将确定岩浆性质的动态变化如何影响地表变形模式。研究DMM模型中随时间变化的应变是如何演变的，以了解岩浆储集层的稳定性。新的DMM模型现在才能探索更现实的动态破坏/稳定性标准。DV3M将阐明岩浆储集层在岩浆补给过程中产生的预期应变率范围。应变率超过新确定的阈值的DV3M模型输出将促进泥浆储集层的脆性行为，并可能导致失效；因此，我们将在理解导致潜在喷发的过程方面提供一个阶段性的改变。将DMM模型应用于目标高危火山中心过去和现在的火山形变。新的DMM模型将应用于日本的苏弗里尔山火山、蒙特塞拉特火山和樱岛火山。需要使用DMM模型对正在进行的变形和储集层稳定性进行准确的分析，以从根本上改进危险评估；继续使用静态模型方法可能会提供不正确的评估，影响喷发潜力分析。应用和好处DV3M将超越最先进的水平，通过更有力和现实地从观测中估计岩浆系统参数，从根本上促进火山变形解释。这些改进将减少风险评估和喷发预测中的不确定性，从而在全球范围内受益于正在变形的火山，特别是我们的目标火山。所制定的办法将在全球范围内适用，并可用于短期和长期风险缓解。

ContextOver 800 million people live near volcanoes, while many more depend on them for their livelihoods. Protecting lives and livelihoods during volcanic eruptions is the key challenge in volcanology, complicated by uncertainties in hazard assessment and eruption forecasting.Measurable ground deformation is one of the main tools used to monitor volcanoes and often results from the injection of magma beneath the surface. By combining measurements of deformation with models we can estimate locations and rates of magma supply that drive the displacements; these parameters feed into hazard assessments and eruption forecasts. However, the majority of models are based on outdated concepts and may be contributing to the noted uncertainties. They assume static fluid filled magma chambers despite a recent and exciting paradigm shift in our understanding of sub-volcanic magmatic systems which indicates magma is rather most likely stored in vertically extensive porous "mush" zones. The static magma chambers are also assumed to rupture (possibly leading to eruption) at a fluid-solid boundary according to a finite stationary failure threshold, but the distinct fluid-solid boundary is now thought to be unlikely in real scenarios, and the system inherently evolves dynamically in response to moving magma rather than statically. Therefore, the simple process of artificially inflating and rupturing a static chamber in the majority of volcano deformation models is a major simplification of reality, and introducing additional uncertainty into crucial model outputs. We do not know the influence of the new mush-paradigm on volcano deformation.Aims and objectivesDV3M is needed to advance a new generation of dynamic magma mush (DMM) volcano deformation models. DV3M aims to resolve the impact of porous magma-mush reservoirs on volcano deformation and reservoir stability. Project objectives are:1. Incorporate magma properties in DMM models that evolve in response to temperature and pressure.Evolution of magma properties cannot be accounted for in commonly employed static models of volcano deformation. DV3M will deliver a suite of DMM volcano deformation models that are coupled with temperature and pressure dependent changes in magma, exploiting new computationally efficient open-source tools. We will determine how dynamic changes in magma properties influence surface deformation patterns.2. Examine how time-dependent strain evolves in DMM models to understand magma-mush reservoir stability.New DMM models only now enable exploration of more realistic dynamic failure/stability criteria. DV3M will illuminate the range of expected strain-rates produced in magma-mush reservoirs undergoing magma recharge. DV3M model outputs with strain rates in excess of a newly determined threshold will promote brittle behaviour of the mush reservoir and could lead to failure; we will therefore provide a step-change in understanding of processes leading to potential eruptions.3. Apply DMM models to past and present periods of volcanic deformation at targeted high-risk volcanic centres.The new DMM models will be applied at Soufriere Hills volcano, Montserrat, and Sakurajima volcano, Japan. Accurate analysis of ongoing deformation and reservoir stability is needed using DMM models to fundamentally improve hazard assessments; continued use of static model approaches may be providing incorrect assessments influencing eruption potential analyses.Applications and benefitsDV3M will push beyond the state-of-the-art and fundamentally advance volcano deformation interpretations by more robustly and realistically estimating magma system parameters from observations. These improvements will reduce uncertainties in hazard assessment and eruption forecasting for benefit globally at deforming volcanoes, and in particular at our target volcanoes. The approaches developed will be globally applicable and of use in short- and long-term risk mitigation.