4DVOLC: Magma storage and ascent in volcanic systems via time resolved HPHT x-ray tomographic experiments and numerical modelling of eruption dynamics

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Volcanoes are amongst the most powerful and dangerous natural manifestations on Earth. Eight million people live in the shadow of volcanoes. Bettering our current understanding of volcano system behaviour to improve hazard assessment and risk mitigation is therefore imperative for scientists and governmental authorities operating in active volcanic areas. The primary goal of this project is to create an empirically constrained quantitative description of magma vesiculation and crystallisation kinetics and to apply this to address key volcanological questions through a numerical model framework and observations of the natural system. To this aim, we will combine in situ 4D (time+space) synchrotron x-ray microtomographic experiments to visualise and quantify magma crystallisation and degassing at HPHT with state-of-the-art numerical modelling and observations of natural volcanic textures. This approach will revolutionise experimental petrology and volcanology and will create a paradigm shift in the ability to understand, quantify and forecast volcanic eruptions and their impact on society and climate. To achieve this goal, we plan to exploit the potential of a new x-ray transparent IHPV (internally heated pressure vessel), which is deployed in the framework of another grant, to address fundamental questions that have puzzled Earth scientists for decades: 1) what is the relationship between magma dynamics and transport at depth and the volcanic activity and signals that we watch at the surface? 2) how and why do transitions between explosive and effusive volcanic activity occur and how can we model and predict them? By exploiting the new IHPV, we will perform studies on magma vesiculation and crystallisation kinetics, which play a key role in such transitions, by applying in situ 4D x-ray computed microtomography imaging to magmas of different compositions, volatile and crystal content. The results of the 4D experiments on magma kinetics at the micro scale will be used to derive improved empirical laws of magma viscosity under evolving crystallisation and vesiculation conditions as a function of cooling and decompression rates, and then will be implemented with these latter into a large scale multiphase, multicomponent numerical model of the physical behaviour of magma in volcanic conduits. The model will be developed at the University of Manchester in collaboration with colleagues from the US. The overall findings will be then validated by, and compared with, observations and measurements from well studied natural volcanic eruptions in Italy and Reunion, which both host hazardous, inhabited active volcanic areas. In the event of an eruption, which is likely to happen on Reunion within the time frame of the project, the model will be used in collaboration with the local volcano observatory to constrain eruption forecasting and evolution in real time. With this holistic approach, the research project will generate an exceptionally reliable tool for investigating and quantifying volcano dynamics in both quiescent and eruptive conditions. Such tool will be used by volcano observatories/stakeholders before and during eruption breakout for tracking changes in volcano surface phenomena (i.e., deformation) and eruptive style and make predictions on the eruption evolution. The multidisciplinary, ground-breaking, scientific nature of the project will have a very strong positive impact on the future of volcanology in the UK, and will increase the UK potential over worldwide research. Ultimately, by exploiting the full potential of the new experimental apparatus, the project will produce a key experimental resource in the UK for future, novel investigations involving scientists from different areas of expertise within natural sciences and engineering.