Probing the dynamics of hydrothermal systems at polar active volcanic calderas and their role in volcanic unrest (ref 4593)

项目背景火山喷发对世界上约10%的人口构成威胁。为了能够进行喷发预测、进行危险评估和减轻风险，彻底了解火山动乱是至关重要的。活跃的火山区，特别是火山口，通常与热液系统的存在有关，热液系统可以结合或独立于活动的岩浆侵入或新的岩浆供应来驱动火山动乱，使得对观测到的动乱信号(例如形变、地震活动、排气)的解释存在问题。极地和亚极地火山口(例如冰岛的克拉夫拉和托尔法约科尔；南极洲的欺骗岛)增加了极端气候条件和冰雪覆盖引起的复杂情况，这影响了其热液系统的补给、应力应变分布及其喷发产物等。与低纬火山口相比，极地/亚极地活动火山口的热液系统动力学仍有许多需要了解。项目目标和方法本项目将询问极地和亚极地火山口热液系统的特点，以加深对其动力学如何决定或影响火山动荡的地球物理迹象的理解。使用传热学、流体流动和固体/岩石力学的数值模型，学生将评估裂缝、火山构造、冰川负荷和其他因素对热液循环及其地表和地下表现(例如，火山变形、地震活动和应力分布)的作用。欺骗岛和托尔法约科尔火山是两个主要的案例研究；研究结果将有助于指导今后对火山动乱的评估，包括火山事件的类型、数量和地点。该项目具有灵活性，可以根据学生的个人兴趣和专长调整项目设计。

Project BackgroundVolcanic eruptions pose a threat to ~10% of the world's population. To enable eruption forecasting, carry out hazard assessments, and mitigate risk, a thorough understanding of volcanic unrest is essential. Active volcanic areas, and calderas in particular, are commonly related to the presence of hydrothermal systems, which can drive volcanic unrest in combination with, or independent of, active magmatic intrusions or renewed magma supply, making the interpretation of observed unrest signals (e.g., deformation, seismicity, degassing) problematic. Polar and sub-polar calderas (e.g., Krafla and Torfajökull, Iceland; Deception Island, Antarctica) have added complications arising from extreme climate conditions and the presence of ice/snow cover, which affect the water recharge of their hydrothermal systems, stress-strain distributions, and the products of their eruptions, amongst others. Compared to lower-latitude calderas, there is still much to understand about hydrothermal system dynamics at polar/sub-polar active calderas.Project Aims and MethodsThis project will interrogate the peculiarities of polar and sub-polar caldera hydrothermal systems to improve understanding of how their dynamics dictate or impact geophysical signs of volcanic unrest. Using numerical modelling of heat transfer, fluid flow and solid/rock mechanics, the student will assess the role of fractures, volcano-tectonics, glacial loading, and others on hydrothermal circulation and its surface and subsurface manifestations (e.g., volcano deformation, seismicity, and stress distributions). Deception Island and Torfajökull volcano form the two main case studies; results will be used to help guide future assessments of volcanic unrest, including the type, amount and location of volcanic events. There is flexibility within the project to adapt project design according to individual student interests and expertise.