University College London Featured PhD Programmes
University of Dundee Featured PhD Programmes
University of Kent Featured PhD Programmes
University of Oxford Featured PhD Programmes
University College London Featured PhD Programmes

The relationship between magma-reservoir evolution and volcano collapse: short- and long-timescale magmatic processes at Montserrat, Ritter and Anak Krakatau


Project Description

Sector collapses are among the largest volume events to affect volcanic systems, potentially involving the rapid displacement of tens of cubic kilometres of rock. There is growing evidence that such substantial changes in surface loading can have profound effects on the stability of an underlying magma reservoir, potentially manifested through shifts in eruption rate or composition and dominant eruptive behaviour. Nevertheless, a detailed understanding of how and why collapses perturb a magma system is lacking, because of the challenges involved in generating high resolution reconstructions of past eruptive activity that span the periods before and after collapse. This project will take advantage of three unusual datasets to address this problem. The approach will draw on marine sediment samples collected offshore Montserrat (Lesser Antilles) and Ritter Island (Papua New Guinea), as well as samples related to the 2018 collapse of Anak Krakatau (Indonesia). These samples and cores preserve a record of activity at these volcanoes before and after major collapse events, and can advance our understanding of how volcanism at arc-volcanic systems responds to sudden changes in surface loading.

Ritter Island was the site of the largest historical sector collapse (around twice the size of the Mount St. Helens event in 1980), in 1888, and recent analysis of samples collected in 2016 indicates that unusually evolved magmas were erupted immediately following collapse, and that subsequent rebuilding of the submarine cone has produced rocks that are compositionally distinct from those erupted before collapse. The event provides an ideal opportunity to better understand the nature of post-collapse changes in activity. The 2016 samples were the first collected from the 1888 collapse. More will be collected on a planned research ship expedition in 2020. The recent devastating collapse of Anak Krakatau was smaller than that at Ritter, occurring on a young, basaltic volcano. Samples available from across the growth history of Anak, including post-collapse material, will allow a detailed petrological investigation of its evolution, testing results from Ritter.

Montserrat has been subject to multiple large scale sector collapses throughout its history, and provides an opportunity to investigate the impacts of collapse on volcanic behaviour over longer (103-5 year) timescales, thus complementing the higher-resolution, shorter timescale cases above. The student would work with extensive core samples from a 2019 marine expedition (M154-2; stored in Bremen, Germany) and IODP 340.

Funding Notes

CENTA studentships are for 3.5 years and are funded by the Natural Environment Research Council (NERC). In addition to the full payment of their tuition fees, successful candidates will receive the following financial support.
• Annual stipend, set at £15,009 for 2019/20
• Research training support grant (RTSG) of £8,000

References

Coussens, MF, D Wall-Palmer, PJ Talling, SFL Watt, M Cassidy et al., 2016. The relationship between eruptive activity, flank collapse, and sea level at volcanic islands: a long-term (>1 Ma) record offshore Montserrat, Lesser Antilles. Geophysics, Geochemistry, Geosystems 17, 2591-2611.
Walter, TR, M Haghsehnas Haghighi, FM Schneider, D Coppola, M Motagh et al., 2019. Complex hazard cascade culminating in the Anak Krakatau sector collapse. Nature Communications 10, 4339.
Watt, SFL, J Karstens, A Micallef, C Berndt, M Urlaub et al., 2019. From catastrophic collapse to multi-phase deposition: flow transformation, seafloor interaction and triggered eruption following a volcanic-island landslide. Earth and Planetary Science Letters 517, 135–147.
Watt, SFL, PJ Talling, ME Vardy, DM Masson, TJ Henstock, V Hühnerbach, TA Minsull, M Urlaub, E Lebas, A Le Friant, C Berndt, GJ Crutchley, J Karstens, 2012. Widespread and progressive seafloor-sediment failure following volcanic debris avalanche emplacement: landslide dynamics and timing offshore Montserrat, Lesser Antilles. Marine Geology, 323–325, 69–94.

Related Subjects

Email Now

Insert previous message below for editing? 
You haven’t included a message. Providing a specific message means universities will take your enquiry more seriously and helps them provide the information you need.
Why not add a message here
* required field
Send a copy to me for my own records.

Your enquiry has been emailed successfully





FindAPhD. Copyright 2005-2019
All rights reserved.