Lascar Volcano, Northern Chile; Evidence for Steady-State Disequilibrium

Abstract

Lascar Volcano, located in the Central Volcanic Zone of Northern Chile, is a medium-to high-K calc-alkaline stratovolcano. Three stages are recognized in the construction of the edifice, with activity ranging from andesitic fissure eruptions to a large- volume dacitic pumice flow, the Soncor Flow. The eruption products are predominantly two- pyroxene andesites and dacites, with some hornblende dacites occurring in the Soncor Flow. Disequilibrium textures resulting from mixing between mafic and acid end-members ...