HR: 14:10h
AN: V53E-03 INVITED    [Abstracts]
TI: Halogen emissions during explosive activity on Mt. Etna
AU: * Burton, M
EM: burton@ct.ingv.it
AF: INGV Catania, Piazza Roma, 2, Catania, 95123, Italy
AU: Allard, P
EM: patrick.allard@cea.fr
AF: Laboratoire Pierre Sue CNRS-CEA, CE-Saclay, Gif/Yvette, 91191, France
AB: The gas composition emitted during an explosive eruption is controlled by several factors including gas transport; gas solubility; diffusion; and fragmentation rocesses. Measurements of gas composition during explosive activity are therefore a rich information source, providing valuable constraints on many volcanic processes. Halogens are particularly useful for tracking the dynamics of explosive activity in basaltic systems, primarily because they exsolve at shallower depths than CO2, H2O and S and are therefore strongly coupled to shallow volcanic processes. In this paper we present an overview of our observations of gas compositions during explosive eruptions on Etna since 2000, with particular emphasis on halogen emissions. Our findings suggest that diffusion-limited halogen degassing is a major factor in controlling the composition of emitted gases, and that this is strongly controlled by the degree of magma fragmentation.
DE: 8430 Volcanic gases
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2007 Fall Meeting