Institute of Geophysics and Tectonics (IGT) PhD Projects
Using Volcano Seismic Signals to Forecast Volcanic Processes
Supervisors: Prof Jurgen Neuberg
Seismic signals on active volcanoes can be separated into three different categories, all of which can be attributed to a specific source mechanism and, therefore, to a specific volcanic process. This project aims to use volcano seismicity to forecast several volcanic processes by estimating magma flux at depth, stress changes in the volcanic edifice, as well as magma extrusion rates.
Rock-fall activity by night at Soufriere Hills volcano on Montserrat, West Indies, which shows continuing cycles of dome growth and collapse accompanied by different types of volcano seismicity.
Seismic data sets from Montserrat (West Indies), Colima (Mexico) and Ruapehu (New Zealand) will be grouped into three classes and analyzed according to their source mechanism: (i) Low-frequency vents are considered to be triggered by stick-slip motion or brittle magma fracture and can be calibrated to easure the ascent of a magma batch in a conduit or dyke. (ii) Volcano–tectonic events are caused by stress changes in the volcanic edifice attributed to magma injection or withdrawal and/or magma de/pressurization. These events will be interpreted together with ground deformation signals. (iii) Rock-fall events are caused by rock avalanches and pyroclastic flows and amplitude estimates can reveal the magma volume that is School of Earth and Environment involved in their generation. Taken these three seismic indicators together we will advance from conceptual models of the generation of volcano seismicity to a quantitative tool that can be used to forecasting volcanic events.
Swarm of low-frequency seismic events which are triggered by magma fracture during ascent in a magma column.
The student will be provided with training in analytical and numerical modeling techniques, applied to seismic wavefields and pressure variations in magma-gas mixtures. Volcanic monitoring experience will be gained at Montserrat Volcano Observatory and at Colima Observatory with whom we have very good links and an existing Memorandum of Understanding controling data exchange and co-operation. Due to the multi-national co-operation and research contacts of the Volcano Study Group at Leeds the student will be part of a colourful and multi-disciplinary group of scientists in the UK and abroad.