Studying dyke propagation paths at Santorini volcano

By Kyriaki (Sandy) Drymoni, Royal Holloway University of London

Santorini volcano is a stratovolcano located in the Aegean Sea, which faced at least 4 caldera collapse events and sequences of Plinian and Intraplinian volcanic eruptions. This great volcanotectonic history exposed a dyke swarm of at least 91 dykes on the 5 km northern caldera wall on Santorini island. Systematic mapping of the dykes in conjunction with a study of their petrogenesis provide insights into the plumbing system and magma dynamics of Santorini volcano.

The dykes propagated through heterogeneous and anisotropic host rocks which affected their pathways: some dykes propagated straight through the stratigraphy but others were arrested or deflected. The combination of field geology with numerical modelling (COMSOL Multiphysics) constrains the parameters that control dyke propagation during emplacement in stratovolcanoes. Preliminary results show that layering, contacts, and local stresses largely control dyke pathways, encouraging either dyke arrest or propagation.

Kyriaki (Sandy) Drymoni is a PhD student at Royal Holloway University of London (Kyriaki.Drymoni.2015@live.rhul.ac.uk). She has completed extensive field campaigns at Santorini and Nisyros Aegean volcanoes thanks to a college scholarship (REID-RHUL) and the Kirsty Brown memorial award (RHUL) respectively. Her research focuses on producing numerical models on likely dyke paths for given loading conditions and magma/host rock properties. That is, to study the fate of dykes injected into the shallow crust, their likely paths and, thereby, the likelihood of dyke-fed volcanic eruptions.  You can read more information on the Santorini dyke swarm in her paper: https://www.nature.com/articles/srep15785