Report on Irruputuncu (Chile-Bolivia) — March 1990
Bulletin of the Global Volcanism Network, vol. 15, no. 3 (March 1990)
Managing Editor: Lindsay McClelland.
Irruputuncu (Chile-Bolivia) Eruption reported by press but geologist observes only fumarolic activity
Please cite this report as:
Global Volcanism Program, 1990. Report on Irruputuncu (Chile-Bolivia) (McClelland, L., ed.). Bulletin of the Global Volcanism Network, 15:3. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199003-355040.
20.73°S, 68.55°W; summit elev. 5163 m
All times are local (unless otherwise noted)
December press reports in Bolivia of an eruption . . .[located 25 km NNW of Olca Volcano] remain unconfirmed, and attempts by Bolivian geologists to fly over the volcano in January were stymied by poor weather. State oil company (ENAP) geologist Patricio Sepulveda reported only normal fumarolic activity at Irruputuncu on 25 March.
Geologic Background. Irruputuncu is a small stratovolcano that straddles the Chile/Bolivia border. It is the youngest and most southerly of a NE-SW-trending chain of volcanoes. It was constructed within the collapse scarp of a Holocene debris avalanche whose deposit extends to the SW. Subsequent eruptions filled much of this scarp and produced thick, viscous lava flows down the W flank. The summit complex contains two craters, the southernmost of which is fumarolically active. The first unambiguous historical eruption took place in November 1995, when phreatic explosions produced dark ash clouds.
Information Contacts: J. Naranjo, SERNAGEOMIN.