Project

Discipline

volcano-tectonics; rift zone; magma intrusion; dike; volcano flank collapse; structural geology; analogue modeling; optical imagery; InSAR

Lead
Les processus volcano-tectoniques sont responsables de l’édification des volcans et des zones de rifts en contrôlant la propagation du magma au travers de fractures. Il s’agit de processus récurrents sur différentes échelles de temps (années, décennies, siècles), ce qui les rend difficiles à étudier. Cependant, leur compréhension est cruciale pour estimer où et quand un volcan entrera en éruption.
Lay summary
Lead Les processus volcano-tectoniques sont responsables de l’édification des volcans et des zones de rifts en contrôlant la propagation du magma au travers de fractures. Il s’agit de processus récurrents sur différentes échelles de temps (années, décennies, siècles), ce qui les rend difficiles à étudier. Cependant, leur compréhension est cruciale pour estimer où et quand un volcan entrera en éruption. Contenu et objectifs du travail de recherche TEMPO a pour but d’identifier les conditions magmatiques et tectoniques qui précèdent les éruptions volcaniques pour mieux prévoir ces dernières. Notre groupe étudiera les récurrences d’évènements volcano-tectoniques en intégrant des mesures de déformation sur le court, moyen et plus long terme avec des données satellitaires et de terrain. Ces recherches auront lieu sur le Kilauea, un des volcans les plus actifs au monde et véritable laboratoire naturel, sujet à de nombreux cycles éruptifs durant les dernières décennies. Le team travaillera également en Oman, une région unique où une forte érosion donne accès aux profondeurs de la croûte océanique. Ici seront visés surtout les mécanismes de propagation du magma et leurs relations à la tectonique. Cette zone d’étude fossile sera ensuite comparée à son équivalent actif en Islande. Contexte scientifique et social du projet de recherche 98% des processus volcano-tectoniques a lieu sur le fond des océans et est à l’origine de la formation de la croûte océanique. Ces évènements restent peu étudiés du fait d’un manque d’accessibilité. TEMPO vise à renforcer nos connaissances en intégrant des données multi spatiales et multi-temporelles. Les processus volcano-tectoniques étant associés à de grandes éruptions et à une forte séismicité, TEMPO aura un impact sur l’évaluation des aléas volcaniques.

Direct link to Lay Summary

Last update: 09.05.2018

Active participation

Self-organised

Communication	Title	Media	Place	Year

Volcano-tectonic processes are the interplay between magma, tectonics and faulting. These processes drive the evolution of divergent plate boundaries and can trigger large magnitude volcanic eruptions and destructive earthquakes. They are recurrent, cover broad time scales from a few days to hundreds of years and often involve reactivation of pre-existing tectonic structures. However, our current understanding of volcano-tectonic processes is still limited due to a lack of integrated strategies covering multi temporal and spatial scales and needs extended method and data integrations to fully understand the processes that control divergent plate boundaries and volcanic activity. TEMPO will address this challenge by studying divergent plate boundaries and large basaltic volcanoes subject to recurring magma injections and flank collapses, from single events to multi-decadal deformation analysis, integrating several remote sensing platforms (satellite, airborne, UAV- Unmanned Aerial Vehicle), structural geology and analogue modelling.TEMPO is built around two main research axes that focus on the deformation at the Earth’s surface over decades, and conjointly to understand the subsurface magma/fluid and faulting processes. Within the first research axis I propose to study the recurrences of volcano-tectonic events from analysing active volcanic fracture zones and by extending the period of observation from single events to several decades, i.e., by integrating various spatial and multi temporal ground deformation data from optical and satellite radar imagery (from 1950’s to 2017). These data will be integrated with field structural geologic investigations to extend the observation period further to recent geological timescales (10^2 to 10^4 years). To cover larger areas and to extract fault styles and fracture mechanisms, a novel automated UAV structural mapping tool will be developed. The aim of the second research axis is to extend the picture of volcano-tectonic processes from the surface down to crustal depths, by determining the role of fault reactivation during magma/fluid propagation, a key parameter for resolving how and where magma is propagating and also better forecasting volcanic eruption locations. Structural field observations will focus on deeply eroded rift zones, collecting deformation data at different crustal levels, from the paleo-surface down to the brittle-ductile boundary where most of the seismicity occurs when magma is propagating along divergent plate boundaries. Within the second research axis, TEMPO will also use 3D analogue experiments based on the field observations to study fluid migration and faulting under different stress conditions to analyse magma propagation pathways. Studying jointly the surface and subsurface volcano-tectonic processes is critical to understand the mechanisms controlling volcano-tectonic events and to produce more accurate forecasting of future activity and mitigate the associated risk and impact. The innovation of TEMPO is the integration of multiple existing state-of-the-art methods dedicated to study volcano-tectonic processes over many temporal and spatial scales, from the surface down to crustal depths within the same project and the same research group composed of the PI and two PhD students. Such a unique approach has never been attempted before and will provide the ideal framework to advance our knowledge of volcano-tectonic processes. This advance can contribute to better forecasts future recurrent large eruptions at divergent plate boundaries and at large unstable volcanoes, both having direct impact on our society with e.g., air traffic perturbation and large destructive earthquakes. With TEMPO, we envision building up an international hub of research dedicated to volcanic processes at the University of Geneva, ensured by active collaborations between the existing research groups working on volcanic processes in the Earth Science Department.