This Small Grant for Exploratory Research (SGER) is supported by the Office of International Science and Engineering in conjunction with the Petrology and Geochemistry program to provide funds for collecting urgent data on a recent explosive eruption of Llaima Volcano in Southern Chile. This explosive basaltic eruption began on 1 Jan 2008 and the field data needs to be collected before the thin deposits are destroyed in the austral winter. The investigators are early career researchers from the fields of physical volcanology and geochemistry who both have experience working in basaltic systems. The project will involve combining field geology and monitoring data with petrological and geochemical analysis of the eruptive products to build an understanding of the eruption system and in particular conduit processes at usually passively degassing volcanoes. This work forms part of a broader research interest in the dynamics of basaltic systems and will form the basis of a PhD thesis for an incoming PhD student.
This eruptive phase of the Llaima volcano began on 1 Jan 2008, with a spectacular fire fountain display lasting 14 hours and continued at lower effusion rates through February and March with the effusion of a lava flow from the summit crater. The intriguing aspect of this eruption is the style of activity emanating from two lateral, vents, which generated frequent small explosions, the plumes of which collapsed and formed pyroclastic flows on numerous occasions. This eruption provides a window of opportunity to test ongoing work by the investigators on passively degassing basaltic systems, based on the neighboring Villarrica volcano and Stromboli, in Italy. In particular, it is planned to investigate the transition of these normally quiescence systems into eruptive cycles, and furthermore probe the nature of the, clearly, complex plumbing system.