AT1-15: Three decades of large explosive eruptions (VEI>4) in the Southern Volcanic Zone: dynamics, monitoring, hazards.

Conveners: Francisco Delgado, Universidad de Chile. Luis Lara, Universidad Austral de Chile. Carlos Cardona, Servicio Nacional de Geología y Minería, SERNAGEOMIN. fdelgado@uchile.cl

Description: The Southern Volcanic Zone (SVZ) of the Andes arc has erupted four times in the past three decades with events larger than VEI 4. These eruptions are Hudson 1991, Chaitén 2008, Cordón Caulle 2011 and Calbuco 2015, and with magmas ranging in composition from basaltic to rhyolitic. These eruptions have made the SVZ the most productive arc on Earth during 1980-2019 in terms of the total erupted mass, with a mass productivity equivalent to that of Kilauea volcano in Hawaii. In particular, Chaitén and Cordón Caulle constitute the only rhyolitic eruptions with detailed visual and instrumental observations. Further, all these eruptions have resulted in widespread damage to the surrounding communities and infrastructure, and whose effects persist for several decades. Therefore, the SVZ constitutes a unique place for the study of the processes that lead to large explosive eruptions. In this session we welcome contributions that span diverse aspects of these events, including but not limited to mechanisms of magma storage and transport, petrogenesis, eruptive dynamics, instrumental monitoring and eruption hazard management, among others.