The large, restless, rhyolitic magma system at Laguna del Maule, southern Andes: Its dynamics and hazards

BRAD SINGER; NATHAN ANDERSEN; CARLOS CARDONA; ALVARO AMIGO; JUDITH FIERSTEIN; PATRICIA SRUOGA

La Serena

Congreso; XIV Congreso Geológico Chileno; 2015

Colegio de Geólogos de Chile

The Laguna del Maule (LdM) volcanic field, central Chile, comprises the highest spatial concentration of young rhyolite in the Southern Andes and is currently in a state of extraordinary unrest (Singer et al., 2014). Since the most recent deglaciation (~25,000 years ago), rhyolite domes and coulées have erupted in a 23 by 17 km ring around the central lake basin. Within this ring, the rate of uplift has been at exceptionally high (>19 cm/yr) since some time before 2007, as measured by satellite geodesy (Fournier et al., 2010; Feigl et al.2014; Le Mével et al., in review). Together with their coherent chemical composition, the distribution of the volcanic products and ongoing unrest suggests that the post-glacial rhyolites are the product of a large, shallow silicic magma reservoir that is active and growing. This magmatic system thus has the potential to produce a large,explosive eruption and thus poses a significant volcanic hazard.