Steam jets from that rose 300-400 m from fumaroles on the SE flank, 200 m below the summit, were observed during dry weather at about noon on 9 and 16 March.

Information Contacts: J. Naranjo, SERNAGEOMIN, Santiago; H. Moreno, Univ de Chile.

Geological Summary. The late-Pleistocene to Holocene Callaqui stratovolcano has a profile of an overturned canoe, due to its construction along an 11-km-long, SW-NE fissure above a 1.2-0.3 million year old Pleistocene edifice. The ice-capped, basaltic andesite volcano contains well-preserved cones and lava flows, which have traveled up to 14 km. Small craters 100-500 m in diameter are primarily found along a fissure extending down the SW flank. Intense solfataric or fumarolic activity occurs at the southern portion of the summit; in 1966 and 1978, red glow was observed in fumarolic areas (Moreno, 1985 pers. comm.). An explosive eruption was reported in 1751 CE, there were uncertain accounts of eruptions in 1864 and 1937, and a small phreatic ash emission was noted in 1980.