Descabezado Grande

Photo of this volcano
Google Earth icon
  Google Earth Placemark
  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 35.58°S
  • 70.75°W

  • 3953 m
    12966 ft

  • 357050
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

Most Recent Weekly Report: 6 March-12 March 2013


OVDAS-SERNAGEOMIN reported that during 1-28 February seismicity increased at Descabezado Grande, in the Laguna del Maule volcanic complex area. There were 127 earthquakes detected, with magnitudes 1.7 or less, mostly comprised of volcano-tectonic earthquakes. The seismic swarms were associated with deformation and considered to be at a high level. On 8 March the Alert Level was raised to Yellow.

Source: Servicio Nacional de Geología y Minería (SERNAGEOMIN)


Most Recent Bulletin Report: March 1982 (SEAN 07:03)


New fumarole in main crater

Fumarolic activity was observed on the morning of 19 March. A white plume was rising from the summit crater during the 3 hours the observer was on Nevados de Chillán Volcano, 160 km to the S. The only recorded eruption at Descabezado Grande, in 1932, was from a crater at its NE foot. Weak fumarolic activity has been reported on the W slope at about 3,500 m, but none had previously been observed in the main crater.

Information Contacts: H. Moreno R., Univ. de Chile, Santiago.

Index of Weekly Reports


2013: March

Weekly Reports


6 March-12 March 2013

OVDAS-SERNAGEOMIN reported that during 1-28 February seismicity increased at Descabezado Grande, in the Laguna del Maule volcanic complex area. There were 127 earthquakes detected, with magnitudes 1.7 or less, mostly comprised of volcano-tectonic earthquakes. The seismic swarms were associated with deformation and considered to be at a high level. On 8 March the Alert Level was raised to Yellow.

Source: Servicio Nacional de Geología y Minería (SERNAGEOMIN)


Index of Bulletin Reports


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.

03/1982 (SEAN 07:03) New fumarole in main crater




Bulletin Reports

All information contained in these reports is preliminary and subject to change.


03/1982 (SEAN 07:03) New fumarole in main crater

Fumarolic activity was observed on the morning of 19 March. A white plume was rising from the summit crater during the 3 hours the observer was on Nevados de Chillán Volcano, 160 km to the S. The only recorded eruption at Descabezado Grande, in 1932, was from a crater at its NE foot. Weak fumarolic activity has been reported on the W slope at about 3,500 m, but none had previously been observed in the main crater.

Information Contacts: H. Moreno R., Univ. de Chile, Santiago.

Volcán Descabezado Grande is a late-Pleistocene to Holocene andesitic-to-rhyodacitic stratovolcano with a 1.4-km-wide ice-filled summit crater. Along with 3788-m-high Cerro Azul, only 7 km to the south, 3953-m-high Descabezado Grande lies at the center of a 20 x 30 km volcanic field. A lateral crater that formed on the upper NNE flank in 1932, shortly after the end of the major 1932 eruption from nearby Quizapu volcano on the north flank of Cerro Azul, was the site of the only historical eruption of Descabezado Grande. The Holocene Alto de las Mulas fissure on the lower NW flank of Descabezado Grande produced young rhyodacitic lava flows. Numerous small late-Pleistocene to Holocene volcanic centers are located north of the volcano. The northernmost of these, Lengua de Vulcano (or Mondaca) produced a very youthful rhyodacitic lava flow that dammed the Río Lentué.

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

Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
1932 Jun 5 ± 5 days 1933 Confirmed 3 Historical Observations Upper NNE slope

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.


Synonyms

Descabezado del Maule

Cones

Feature Name Feature Type Elevation Latitude Longitude
Chivato, Volcán Cone 2080 m 35° 29' 0" S 70° 51' 0" W
Manantial Pelado Stratovolcano 2850 m 35° 30' 0" S 70° 49' 0" W
Palizada, Volcán Stratovolcano 2640 m 35° 32' 0" S 70° 49' 0" W
Rajaderas, Volcán Stratovolcano 3000 m 35° 32' 0" S 70° 43' 0" W

Craters

Feature Name Feature Type Elevation Latitude Longitude
Mulas, Alto de las Fissure vent 2550 m 35° 33' 0" S 70° 48' 0" W

Domes

Feature Name Feature Type Elevation Latitude Longitude
Lengua de Vulcano
    Mondaca
Dome 2048 m 35° 27' 51" S 70° 48' 1" W
The summit of Descabezado Grande volcano is truncated by a 1.4-km-wide, ice-filled summit crater, giving rise to its name, which means "Large Headless Volcano." The only historical eruption of this late-Pleistocene to Holocene volcano, seen here from the west, occurred in 1932 from an upper NNE-flank vent. The 1932 crater lies out of view below and to the left of the notch at the left side of the summit crater.

Photo by Hugo Moreno (University of Chile).
Volcán Descabezado Grande, seen here from the west, is a late-Pleistocene to Holocene stratovolcano with a 1.4-km-wide ice-filled summit crater. The Holocene Alto de las Mulas fissure on the lower NW flank (out of view to the left) produced young rhyodacitic lava flows. A lateral crater formed on the upper NNE flank in 1932, shortly after the end of the major 1932 eruption from nearby Quizapú volcano. This was the site of the only historical eruption of Descabezado Grande.

Photo by Hugo Moreno (University of Chile).
Descabezado Grande (center) and Cerro Azul (middle right), seen here from the NW, are the most prominent features of a large volcanic field. The most active of the two large stratovolcanoes is 3810-m-high Cerro Azul. Quizapú, a vent that formed in 1846 on the northern flank of Cerro Azul, was the source of one of the world's largest explosive eruptions of the 20th century in April 1932. The eruption created a 600-700 m wide crater and ejected 9.5 cu km of dacitic tephra. The only historical eruption of Descabezado Grande took place later in 1932.

Photo by Jeff Post, 1988 (Smithsonian Institution).
The 2048-m-high Mondaca lava dome (bottom center) produced a large youthful rhyodacitic lava flow that traveled north and dammed the Rio Lontue, eventually reaching 7 km to the NW (upper right). This eruption may have taken place during historical time, possibly during the 19th century. The solitary small Mondaca lava dome is located NNW of the Descabezado volcano complex and west of the Calabozos caldera.

Photo by Instituto Geográfico Militar, courtesy of Oscar González-Ferrán (University of Chile).

The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography. Discussion of another volcano or eruption (sometimes far from the one that is the subject of the manuscript) may produce a citation that is not at all apparent from the title.

Casertano L, 1963a. Chilean Continent. Catalog of Active Volcanoes of the World and Solfatara Fields, Rome: IAVCEI, 15: 1-55.

Gonzalez-Ferran O, 1995. Volcanes de Chile. Santiago: Instituto Geografico Militar, 635 p.

Hildreth W, Drake R E, 1992. Volcan Quizapu, Chilean Andes. Bull Volc, 54: 93-125.

Hildreth W, Moorbath S, 1988. Crustal contribution to arc magmatism in the Andes of central Chile. Contr Mineral Petr, 98: 455-489.

Volcano Types

Stratovolcano(es)
Fissure vent(s)
Pyroclastic cone(s)
Lava dome

Tectonic Setting

Subduction zone
Continental crust (> 25 km)

Rock Types

Major
Andesite / Basaltic Andesite
Dacite

Population

Within 5 km
Within 10 km
Within 30 km
Within 100 km
39
142
3,454
704,116

Affiliated Databases

Large Eruptions of Descabezado Grande Information about large Quaternary eruptions (VEI >= 4) is cataloged in the Large Magnitude Explosive Volcanic Eruptions (LaMEVE) database of the Volcano Global Risk Identification and Analysis Project (VOGRIPA).
WOVOdat WOVOdat is a database of volcanic unrest; instrumentally and visually recorded changes in seismicity, ground deformation, gas emission, and other parameters from their normal baselines. It is sponsored by the World Organization of Volcano Observatories (WOVO) and presently hosted at the Earth Observatory of Singapore.
EarthChem EarthChem develops and maintains databases, software, and services that support the preservation, discovery, access and analysis of geochemical data, and facilitate their integration with the broad array of other available earth science parameters. EarthChem is operated by a joint team of disciplinary scientists, data scientists, data managers and information technology developers who are part of the NSF-funded data facility Integrated Earth Data Applications (IEDA). IEDA is a collaborative effort of EarthChem and the Marine Geoscience Data System (MGDS).
Smithsonian Collections Search the Smithsonian's NMNH Department of Mineral Sciences collections database. Go to the "Search Rocks and Ores" tab and use the Volcano Name drop-down to find samples.