IPGP - Campus Jussieu
Séminaires Géomatériaux et Environnement
Department of Geography, Downing Place,Cambridge & Institut des Sciences de la Terre d'Orléans
Résumé Erebus is well-known for its sustained lava lake, alkaline intraplate character, and, of course, its southerly latitude. The volcano displays two kinds of behaviour: (i) lava lake, and (ii) lava lake plus intermittent Strombolian eruptions. Thanks to a combination of melt inclusion modelling (by Roberto Moretti) and high time resolution gas measurements and thermal imaging at the crater, we are building a new conceptual model for the plumbing system of Erebus – from the deep basanite supply, through intermediate magmas, to the evolved phonolite lake. On one level, the behaviour is simple, stable, sustained but the magma differentiation, mantle-to-surface degassing, conduit geometry, and the moderate viscosity of the phonolitic magma superimpose fascinating complexity on the long-lived lava lake. I will highlight what we have been doing on Erebus (principally using remote sensing techniques) over the past 5 years or so, and summarise where we have reached in our understanding of the volcano’s behaviour. I will touch briefly on the atmospheric chemistry of the Erebus plume, including its effect on ozone.