Common origin or domino effect? Deformation and seismicity at Western Galápagos Volcanoes

This project will use satellite radar measurements of displacement at the millimetre scale to explore recently proposed deep connections between the volcanoes of the Western Galápagos. We will integrate satellite radar and seismic observations with petrological understanding to test to what extent correlations in deformation time series are related to deep connections in magma supply, or moderated by shallow stress changes.

To understand the dynamics of magmatic systems we need to characterise both the vertical and lateral connections through the crust, which may be steady or intermittent. Combining geodetic and seismic measurements is a particularly powerful way to do this, and has been successfully applied in other settings. Here, we propose to develop previous research into apparent correlations in Galápagos time series by integrating seismic data into our analysis and applying machine learning methods to reveal underlying structures of the data. New models of magmatic system architecture need be consistent both with geophysical data and with the distinct isotopic signatures of rocks from different Galápagos volcanoes that indicate supply from separate sources of melt.

The cluster of the volcanoes of the western Galápagos show exceptionally high rates of eruption, unrest and deformation. They have a range of maturities of magmatic systems, and are particularly suitable for study with Interferometric Synthetic Aperture Radar (InSAR), due to high magnitude displacements from shallow reservoirs and good phase coherence. Both eruptions and inter-eruptive periods show measureable deformation and seismicity. This project will study historical catalogues of deformation and seismicity, as well as making new measurements of current deformation in the Galápagos.

This studentship will use freely available, global satellite datasets, especially Sentinel-1 imagery, along with machine learning methods such as blind source separation to uncover hidden structures in displacement time series (Ebmeier, Leeds). It will also integrate seismic (Bell, Edinburgh) and geodetic datasets with petrological understanding (Ferguson, Leeds) for the development of geophysical models. This project will therefore suit a student excited both by working with complex earth observation data and with a general interest in geophysics or volcanology. The student will have the opportunity to work with COMET scientists working on automated InSAR processing at the University of Leeds, and would be part of the COMET network of UK of scientists applying Earth Observation to Geohazards. The supervision team lead multiple ongoing projects in the Galápagos, including new seismic field campaigns. Ebmeier and Bell have long standing and successful collaborations with scientists at the Instituto Geofisico, Quito, who are responsible for volcano monitoring in Ecuador and would be collaborators for this studentship. This studentship will be supported by international cooperation, including the potential for collaborative research visits to Ecuador.

1. Reddin, E., Ebmeier., S.K., Rivalta, E., Bagnardi, M., Baker, S., Bell, A.F., Morgan, D.J., Mothes, P., Aguaiza, S., & Espin Bedon, P. Magmatic Connectivity among Six Galapagos Volcanoes Revealed by Satellite Geodesy, Nat Comm. In press Oct 2023.
2. Bagnardi, M., & Amelung, F. (2012). Space‐geodetic evidence for multiple magma reservoirs and subvolcanic lateral intrusions at Fernandina Volcano, Galápagos Islands. Journal of Geophysical Research: Solid Earth, 117(B10).
3. Bell, A.F., La Femina, P.C., Ruiz, M., Amelung, F., Bagnardi, M., Bean, C.J., Bernard, B., Ebinger, C., Gleeson, M., Grannell, J. and Hernandez, S., 2021. Caldera resurgence during the 2018 eruption of Sierra Negra volcano, Galápagos Islands. Nature communications, 12(1), pp.1-9.
4. Ebmeier, S. K. (2016). Application of independent component analysis to multitemporal InSAR data with volcanic case studies. Journal of Geophysical Research: Solid Earth, 121(12), 8970-8986.