The federation
Intranet
ARC-VANUATU Project
**Comprendre des mécanismes à l’origine des panaches volcaniques et des forts séismes de subduction.
Coordinator : B. Pelletier (Géosciences Azur)
ISTerre research team involved : Volcanic geophysics & geothermics->rubrique1117]
Collaborations :
- Géosciences Azur
- IPGP
- Laboratoire Pierre Sue CNRS-CEA Saclay
- Laboratoire Magmas et Volcans Clermont Ferrand
- Universités Lyon, Brest, Montpellier
- Département de la Géologie, des Mines et des Ressources en Eau et le Service Topographique du Vanuatu.
**Summary
The ARC-VANUATU program aims to understand the mechanisms at the origin of volcanic eruptions (degassing dynamics and eruptive cyclicity, formation of plumes) and strong earthquakes (accumulation modalities and stress relaxation, relationship between seismic cycle and relief genesis) in subduction context, and to seek signals to help predict such destructive hazards. Vanuatu’s converging margin, which is young and very active, provides very favourable conditions for observation, quantification and understanding of processes. Current movements are exceptionally high, from 10 to 17 cm/year for the convergence rate and up to cm/year for vertical movements. Earthquakes are frequent : an earthquake of magnitude >= to 7 occurs on average per year. The activity of volcanoes, linked to water-rich magmas, is highly explosive. Eruptions are frequent, even almost permanent, and can generate plumes and eruptive columns.