School of Earth Sciences, Leeds University

Ph.D. project proposal

Combining magma flow modelling and seismicity on Montserrat

Supervisor: Professor Jurgen Neuberg

Montserrat - eruption and seismogram Soufriere Hills volcano on the Caribbean Island of Montserrat shows ongoing volcanic activity since 1996, in a well-established pattern of dome growth and dome collapse. In the last few years, several international research projects focused on Montserrat and made Soufriere Hills volcano one of the most intensely studied volcanoes wordwide. The Volcano Seismology Group at Leeds is involved in several international research initiatives on Montserrat funded by NERC, the European Commission and by the National Science Foundation in the US.

So-called low-frequency seismic events (LFs) play a key role in the understanding of the internal dynamics of the volcanic system. They show a well-established pattern of swarms always preceding mayor dome collapses and have therefore a great potential to be used for forecasting of volcanic hazard. The characteristics of these seismic events are controlled by the magma properties, and
modelling these is an essential component to understand under which conditions brittle failure can occur in magma, leading to the generation of the seismic events. In the last years we developped finite element models to study magma flow
in two dimensions, i.e., varying with depth and accross the conduit. The magma is modelled as a three phase flow of crystals, gas and melt. These
models allow us to determine the properties such as density, viscosity and elastic parameters, such that we can now compute the seismic trigger and wave propagation in such a magma conduit and the surrounding edifice.

This PhD project will be concerned with the modelling of several magma flow conditions and the corresponding seismic wavefield. Comparison with seismic data from Montserrat will constrain the modelling parameters. The project aims to uncover the interaction of magma and elastic parameters to invert directly for magma properties and their changes from analysing the characteristics of the seismic signals.

The student will be provided with training in analytical and numerical modelling techniques, applied to seismic wavefields and pressure variations in magma-gas mixtures. Volcanic monitoring experience will be gained on the Caribbean island of Montserrat. Due to the multi-national co-operation and research contacts of the Volcano Seismology Group at Leeds, the student will be part of a colourful and multi-disciplinary group of scientists from the US, the UK and several (other) European countries.

References:

<>Neuberg, J., Luckett, R., Baptie, B., and K. B. Olson, 2000, Models for tremor and low-frequency events on Montserrat, J. Vol. Geotherm. Research, 101, 83-104.<>

Website of the Volcano Seismology Group at Leeds: http://earth.leeds.ac.uk/vsgleeds/

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