Abstract

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 petrological, geochemical and geophysical studies, we are building a conceptual model for the plumbing system of Erebus – from the deep supply from the mantle to the evolved phonolite lava lake. On one level, the behaviour is simple, stable and sustained but the magma differentiation, mantle-to-surface degassing, conduit geometry, and 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 over the past decade, 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 gas/aerosol plume, including its effect on ozone.