Huanquihue volcano itself is eroded, but El Escorial cinder cone has been active in the Holocene. One of its tephras overlies an older formation that was erupted 1400 BP.[2] Lavas from this cone form a peninsula in Lake Epulafquen and modified the local hydrography. Another cinder cone La Angostura formed a peninsula separating the lakes Epulafquen and Huechulafquen. This cone has three craters.
A tephra layer of black trachyandesite has been linked to Huanquihue and is dated 4028-4212 BP.[3]Varve count dating has indicated that tephras in Lake Villarrica and Lake Calafquen erupted presumably in 1591 are compositionally similar to Huanquihue scorias.[4]AVEI-3 eruption of basaltictrachyandesite has been dated at that year.[3] Oral tradition reports the occurrence of an eruption at the end of the 17th century.[5]
González-Ferrán, Oscar (1995). Volcanes de Chile. Santiago, Chile: Instituto Geográfico Militar. p. 640 pp. ISBN978-956-202-054-1. (in Spanish; also includes volcanoes of Argentina, Bolivia, and Peru)
