Postdoctoral Fellowship: EAR-PF: Understanding the Mechanics of Caldera Collapse Eruptions

许多火山爆发都涉及破火山口崩塌，当火山爆发进行时，覆盖在岩浆库上的一段岩石向下下降。在地球历史上最大规模的火山爆发期间，以及过去几十年的多次火山爆发期间，都发生了火山口坍塌。然而，控制火山口塌陷喷发时间演变的因素知之甚少，这限制了我们推断过去喷发条件和预测正在进行或未来喷发的能力。该项目将开发包括地震和岩浆动力学在内的火山口崩塌模拟，然后将模拟与各种类型的地质数据和火山监测数据进行比较。该项目将量化对火山口崩塌喷发演化的控制，并对几座火山的重要岩石和岩浆系统特性进行约束，其中包括夏威夷的克基劳厄火山。除了向火山观测站传达结果外，还将制作2018年k<e:1>劳厄火山喷发的沉浸式动画和声音，以进行更广泛的宣传。该项目将研究基性和硅质火山喷发时火山口崩塌的时间动力学。它将研究是什么控制了喷发的偶然性，以及这如何影响喷发制度和整体喷发量和持续时间。该项目将开发结合弹性和多相流体力学的三维数值模型，包括地震物理和岩浆上升动力学。模拟将与最近火山喷发的地球物理和视频数据进行比较，以约束环断层的几何形状和摩擦特性。模拟还将与较早的硅质火山喷发的地质和岩石学数据进行比较，以研究不同的喷发前储层条件（包括岩浆分层和熔融透镜分布）如何影响火山喷发和由此产生的矿床。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Many volcanic eruptions involve caldera collapse, where a section of rock overlying a magma reservoir drops downward as an eruption progresses. Caldera collapse has occurred during the largest explosive eruptions in Earth’s history, but also during multiple eruptions in the past few decades. However, the factors controlling the time evolution of caldera collapse eruptions are poorly understood, which limits our ability to infer past eruptive conditions and make forecasts about ongoing or future eruptions. This project will develop caldera collapse simulations that include both earthquakes and magma dynamics, then compare simulations to various types of geologic data and volcano monitoring data. The project will quantify controls on caldera collapse eruption evolution and constrain important rock and magma system properties at several volcanoes, including Kīlauea in Hawaii. In addition to communicating results to volcano observatories, immersive animations and sonifications of the 2018 Kīlauea eruption will be produced for broader outreach.This project will study temporal dynamics of caldera collapse in both mafic and silicic eruptions. It will examine what controls eruption episodicity, and how this influences eruptive regimes and overall eruption volume and duration. This project will develop 3D numerical models that couple elastic and multiphase fluid mechanics, including earthquake physics and magma ascent dynamics. Simulations will be compared to geophysical and video data from recent mafic eruptions to constrain ring fault geometry and frictional properties. Simulations will also be compared to geologic and petrologic data from older silicic eruptions to examine how different proposed pre-eruptive reservoir conditions, including magma stratification and melt lens distributions, influence eruptions and the resulting deposits.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.