Irruputuncu

Photo of this volcano
  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 20.73°S
  • 68.55°W

  • 5163 m
    16935 ft

  • 355040
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

Most Recent Bulletin Report: January 1997 (BGVN 22:01) Citation IconCite this Report


Minor, late-1995 eruption; the first unambiguous modern report

In the course of field work on volcanic rocks in the region, Anita Grunder observed a dark, vertical plume coming from the top of Irruputuncu at about 1000 on 26 November 1995. This dark plume lasted a few minutes, then returned to a white plume, and then again became dark and returned to white. The dark plume was dark gray to black and of the same puffy form as the white plume. The plumes dispersed very slowly to the E and the column height was same whether black or white. It was hard to judge the column size, but it seemed perhaps a few times the relief of the volcano suggesting they were kilometers tall. Grunder's field assistant, Maximino Burotto Huerta, said he had seen similar behavior on 1 September. Ordinarily, either a white wisp of steam or nothing is seen emanating from the peak. The sighting on 26 November was from ~30 km SSE, not far from the village of Ujina.

Grunder was in the area for 31 days between 24 August and 5 December 1995, though typically not in sight of the volcano. She observed no plumes on 27 November and 1-5 December 1995. These observations suggested that the activity consisted of modest phreatic eruptions.

Available literature lacks clear documentation of any historical Irruputuncu eruptions. The stratovolcano was the subject of unconfirmed press reports of an eruption in December 1989, but when visited by a state geologist on 25 March 1990 he found only fumarolic activity (BGVN 15:03). Irruputuncu sits within the collapse scarp related to a Holocene debris avalanche. There are two summit craters, the southernmost of which has been fumarolically active.

Information Contacts: Anita Grunder, Department of Geosciences, 104 Wilkinson Hall, Oregon State University, Corvallis OR 97331, USA (Email: grundera@ava.bcc.orst.edu).

The Global Volcanism Program has no Weekly Reports available for Irruputuncu.

Bulletin Reports - Index


Reports are organized chronologically and indexed below by Month/Year (Publication Volume:Number), and include a one-line summary. Click on the index link or scroll down to read the reports.

03/1990 (BGVN 15:03) Eruption reported by press but geologist observes only fumarolic activity

01/1997 (BGVN 22:01) Minor, late-1995 eruption; the first unambiguous modern report




Information is preliminary and subject to change. All times are local (unless otherwise noted)


March 1990 (BGVN 15:03) Citation IconCite this Report


Eruption reported by press but geologist observes only fumarolic activity

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.

Information Contacts: J. Naranjo, SERNAGEOMIN.


January 1997 (BGVN 22:01) Citation IconCite this Report


Minor, late-1995 eruption; the first unambiguous modern report

In the course of field work on volcanic rocks in the region, Anita Grunder observed a dark, vertical plume coming from the top of Irruputuncu at about 1000 on 26 November 1995. This dark plume lasted a few minutes, then returned to a white plume, and then again became dark and returned to white. The dark plume was dark gray to black and of the same puffy form as the white plume. The plumes dispersed very slowly to the E and the column height was same whether black or white. It was hard to judge the column size, but it seemed perhaps a few times the relief of the volcano suggesting they were kilometers tall. Grunder's field assistant, Maximino Burotto Huerta, said he had seen similar behavior on 1 September. Ordinarily, either a white wisp of steam or nothing is seen emanating from the peak. The sighting on 26 November was from ~30 km SSE, not far from the village of Ujina.

Grunder was in the area for 31 days between 24 August and 5 December 1995, though typically not in sight of the volcano. She observed no plumes on 27 November and 1-5 December 1995. These observations suggested that the activity consisted of modest phreatic eruptions.

Available literature lacks clear documentation of any historical Irruputuncu eruptions. The stratovolcano was the subject of unconfirmed press reports of an eruption in December 1989, but when visited by a state geologist on 25 March 1990 he found only fumarolic activity (BGVN 15:03). Irruputuncu sits within the collapse scarp related to a Holocene debris avalanche. There are two summit craters, the southernmost of which has been fumarolically active.

Information Contacts: Anita Grunder, Department of Geosciences, 104 Wilkinson Hall, Oregon State University, Corvallis OR 97331, USA (Email: grundera@ava.bcc.orst.edu).

Eruptive History


Summary of Holocene eruption dates and Volcanic Explosivity Indices (VEI).


Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
1995 Sep 1 1995 Sep 26 Confirmed 2 Historical Observations
[ 1989 Dec ] [ Unknown ] Uncertain    

This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.

Photo Gallery


Steam rises from the fumarolically active southern summit crater of Irruputuncu, a small stratovolcano that straddles the Chile/Bolivia border. Irruputuncu, seen here from the WSW, was constructed within the collapse scarp of a Holocene debris avalanche whose deposit extends to the SW. Levees of viscous lava flows down the western flank of an edifice that was constructed within this scarp are seen at the lower left. The first unambiguous historical eruption from Irruputuncu took place in November 1995.

Photo by José Naranjo, 2001 (Servico Nacional de Geologica y Mineria).
See title for photo information.

Smithsonian Sample Collections Database


There are no samples for Irruputuncu in the Smithsonian's NMNH Department of Mineral Sciences Rock and Ore collection.

Affiliated Sites