Crystal and melt inclusion timescales reveal the evolution of magma migration before eruption

TitleCrystal and melt inclusion timescales reveal the evolution of magma migration before eruption
Publication TypeJournal Article
Year of Publication2018
AuthorsRuth DCS, Costa F, de Maisonneuve CBouvet, Franco L, Cortés JA, Calder ES
JournalNature Communications
Volume9
Date Published07/2018
Abstract

Volatile element concentrations measured in melt inclusions are a key tool used to understand magma migration and degassing, although their original values may be affected by different re-equilibration processes. Additionally, the inclusion-bearing crystals can have a wide range of origins and ages, further complicating the interpretation of magmatic processes. To clarify some of these issues, here we combined olivine diffusion chronometry and melt inclusion data from the 2008 eruption of Llaima volcano (Chile). We found that magma intrusion occurred about 4 years before the eruption at a minimum depth of approximately 8 km. Magma migration and reaction became shallower with time, and about 6 months before the eruption magma reached 3–4 km depth. This can be linked to reported seismicity and ash emissions. Although some ambiguities of interpretation still remain, crystal zoning and melt inclusion studies allow a more complete understanding of magma ascent, degassing, and volcano monitoring data.