The alignment is attributed to the existence of an old fracture in the crust, the North West-South East trending Gastre Fault Zone, the other volcanoes in the chain, Quetrupillán and Lanín, are far less active.
The alignment is attributed to the existence of an old fracture in the crust, the North West-South East trending Mocha-Villarrica Fault Zone Dzierma et al., 2012. Plate interface lock and reactivation of the subducted Valdivia Fracture Zone, the other volcanoes in the chain, Quetrupillán and Lanín, are far less active.