Exploring the eruptive behaviour of a rare young stratovolcano

Project overview

Subduction zone volcanoes are notoriously dangerous and unpredictable. But did they behave differently when they were young?

Here, pre-eruptive magmatic processes and timescales of a rare, young stratovolcano (Bagana, Papua New Guinea) will be compared to an old stratovolcano (Etna) to explore how eruption size, style and timescales change as volcanoes age. 

Project description

Volcanoes are fueled by magmatic plumbing systems that connect the Earth’s mantle with the surface. Most present-day subduction zone volcanoes have mature plumbing systems that grew in size and complexity over long time periods[1], producing eruptions with diverse magma compositions, assembly mechanisms and explosivities. This diversity of eruption styles (effusive/explosive), sizes, and pre-eruptive unrest periods (days/decades) pose fundamental challenges to volcanic risk reduction.

By contrast, the plumbing systems of young, immature stratovolcanoes are less complex, resulting in potentially less diverse eruption mechanisms and styles. However, due to their scarcity, young stratovolcanoes remain poorly understood. 

This project will overcome this limitation by studying a young, persistently active stratovolcano (Bagana, Papua New Guinea) to catalogue its eruptive history and characterize the dynamics and timescales of magma assembly prior to eruptions. This unique dataset will be compared with a mature reference volcano (Etna, Italy; fieldwork optional) and with published data from other arc volcanoes. 

The student will acquire high-resolution chemical maps of fresh volcanic rock samples using correlative multimodal imaging involving SEM, electron microprobe, and laser ablation time-of-flight mass spectrometry. These maps will capture the full complexity of the plumbing systems by combining textural analysis (to constrain magmatic processes[2]) with diffusion chronometry in zoned minerals (to retrieve pre-eruptive magmatic timescales[3]). 

This work will give important insights into the evolution of stratovolcanoes and their plumbing systems and test whether their eruptive behaviour becomes more diverse over time. These results will be crucial for volcano monitoring and risk reduction efforts at subduction zone volcanoes worldwide.  

Training

Our programme provides comprehensive personal and professional development training alongside extensive opportunities for students to expand their multi-disciplinary outlook through interactions with a wide network of academic, research and industrial/policy partners. The student will be registered at the University of Southampton, hosted at the National Oceanography Centre, and work collaboratively with the Natural History Museum. 

Specific training will include:  

• Fieldwork and sampling at Etna (Italy; optional) 
• optical microscopy 
• imaging and compositional analysis of volcanic rock samples within a correlative imaging framework using electron probe microanalyser (EPMA, at the Natural History Museum), scanning electron microscopy (SEM), and time-of-flight mass spectrometry (ToF-MS) 
• diffusion modelling using MATLAB 
• quantitative textural analysis.  
• Written communication, literature review and presentation skills 
• Data management skills 
• The student will further benefit from outreach opportunities at the Natural History Museum and have opportunities to attend (inter)national meetings, workshops and conferences.

Entry requirements

A UK bachelor’s degree with upper second-class honours or higher in a relevant subject. See international equivalent qualifications on our website.

English language: IELTS 6.5 overall, with a minimum of 6.0 in all components. We accept other English language tests.

Further reading

Edmonds, M., Cashman, K. V., Holness, M., & Jackson, M. (2019). Architecture and dynamics of magma reservoirs. Philosophical Transactions of the Royal Society A, 377(2139), 20180298. https://doi.org/10.1098/rsta.2018.0298

Mangler, M. F., et al. (2024). Crystal resorption as a driver for mush maturation: an experimental investigation. Journal of Petrology, egae088. https://doi.org/10.1093/petrology/egae088

Mangler, M. F., Petrone, C. M., & Prytulak, J. (2022). Magma recharge patterns control eruption styles and magnitudes at Popocatépetl volcano (Mexico). Geology, 50(3), 366-370. https://doi.org/10.1130/G49365.1