Session outline

Solid Earth Sciences(S) Session Sub Category Volcanology(VC) Session ID S-VC11 Title Volatiles and volcanoes: the role of volatiles in determining how and when volcanoes erupt Short title Volatiles and volcanoes Convener Name Iona McIntosh Affiliation Japan Agency for Marine-Earth Science and Technology Email i.m.mcintosh@jamstec.go.jp Co-convener 1. Name Atsushi Toramaru Affiliation Department of Earth and Planetary Sciences, Faculty of Sciences, Kyushu University Email toramaru@geo.kyushu-u.ac.jp Co-convener 2. Name Alexander Nichols Affiliation Japan Agency for Marine Earth Science and Technology Email nichols@jamstec.go.jp International Symposium 'International Symposium' in addition to Scientific session. Language English Scope The volatile content of magma is a key factor in determining the eruption style of a volcano. Dissolved volatiles such as H2O, CO2, S and F etc. affect melt viscosity and other physical properties, while volatile exsolution further modifies magma rheology and drives magma ascent via the nucleation and growth of bubbles. Volatiles, melt viscosity and bubble growth dynamics are thus interdependent parameters that directly affect physical eruption mechanisms such as style and depth of magma fragmentation. This session will explore the relationship between volatiles and magmatic processes, from source to surface and micro- to macro-scale, by examining how magmatic volatile contents, physical controls on volatile exsolution, dynamics of bubble growth, development of degassing pathways, and surface gas emissions relate to physical eruption mechanisms, and what evidence for these can be found in eruption products and geophysical and geochemical observational records. We encourage submissions from a broad range of approaches, including geochemical analyses, experimental studies, numerical modelling and field observations, and particularly encourage presentations of new investigative techniques. Type of presentation Oral and Poster presentation Invited papers