Global Volcanism Program

Most Recent Bulletin Report: March 1987 (SEAN 12:03) Cite this Report

Active solfatara field found

An active solfataric field was detected in one of Tolguaca's NW craters (at 38.29°S, 71.67°W) during a March 1986-January 1987 geologic study. Several vents up to 2 m wide covered an area of ~200 m². The vents emitted boiling water, high pressure steam, and H₂S, with a jet-like noise. The entire area showed intense alteration and a small amount of sulfur deposition.

Information Contacts: H. Moreno, Univ de Chile.

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

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.

03/1987 (SEAN 12:03) Active solfatara field found

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

March 1987 (SEAN 12:03) Cite this Report

Active solfatara field found

An active solfataric field was detected in one of Tolguaca's NW craters (at 38.29°S, 71.67°W) during a March 1986-January 1987 geologic study. Several vents up to 2 m wide covered an area of ~200 m². The vents emitted boiling water, high pressure steam, and H₂S, with a jet-like noise. The entire area showed intense alteration and a small amount of sulfur deposition.

Information Contacts: H. Moreno, Univ de Chile.

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

Tolguaca

Cones

Feature Name

Feature Type

Elevation

Latitude

Longitude

Caracol, Volcán

Cone

1455 m

38° 21' 24" S

71° 41' 32" W

Pemehue

Cone

2192 m

38° 17' 56" S

71° 40' 34" W

Basic Data

Volcano Number

Last Known Eruption

Elevation

Latitude
Longitude

357093

4000 BCE

2,739 m / 8,986 ft

38.31°S
71.645°W

Morphology

Volcano Landform
Composite

Volcano Types
Stratovolcano
Pyroclastic cone(s)

Rock Types

Major
Andesite / Basaltic Andesite
Basalt / Picro-Basalt

Tectonic Setting

Subduction zone
Continental crust (> 25 km)

Population

Within 5 km
Within 10 km
Within 30 km
Within 100 km

82
494
13,873
567,185

Geological Summary

Tolhuaca (or Tolguaca) is a late-Pleistocene to Holocene stratovolcano located immediately NW of Lonquimay volcano. A NW-SE zone of aligned summit craters is youngest to the NW. Another group of vents cutting the south and east flanks is oriented SW-NE, parallel to the zone of flank vents on Lonquimay, and is of post-glacial age (Moreno and Gardeweg 1989). Reports of eruptions in 1876 and on 7 January 1933 are not confirmed; the latter date probably refers to an eruption of Lonquimay or Llaima (Petit-Breuilh 1994, pers. comm.). Polanco et al. (2000) stated that explosive activity consisted of three VEI 3-4 eruptions between 8050 and 6590 BP. The Pemehue volcanic trend on the NW flank was noted by Naranjo (pers. comm. 2010) in Melosh et al. (2012) as having post-glacial lava flows dated at less than 6,000 years old. Only fumarolic activity has occurred from this basaltic-andesitic volcano during historical time. Fumaroles and hot springs are common across the NW flank where there is an active geothermal reservoir (Melosh et al., 2012).

References

The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography.

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

Melosh G, Moore J, Stacey R, 2012. Natural reservoir evolution on the Tolhuaca Geothermal Field, southern Chile. PROCEEDINGS, Thirty-Sixth Workshop on Geothermal Reservoir Engineering, Stanford University, Stanford, California, January 30-February 1, 2012.

Moreno H, 1974. Airplane flight over active volcanoes of central-south Chile. Internatl Symp Volc Andean & Antarctic Volc Problems Guidebook, Excur D-3, 56 p.

Moreno H, Gardeweg M C, 1989. La erupcion reciente en el complejo volcanico Lonquimay (Diciembre 1988-), Andes del Sur. Rev Geol Chile, 16: 93-117.

Moreno H, Naranjo J A, 1991. The southern Andes volcanoes (33°-41° 30' S), Chile. 6th Geol Cong Chile, Excur PC-3, 26 p.

Petit-Breuihl M E, 1994. (pers. comm.).

Polanco E, Naranjo J A, Young S, Moreno H, 2000. Volcanismo explosive Holoceno en la Cuenca del alto Biobio, Andes del Sur (37°45’-30°30’S). IX Congreso Geologico Chileno, 31 Julio-4 Agosto, 2000. Puerto Varas, Chile.

Sanchez-Alfaro P, Reich M, Arancibia G, Pérez-Flores P, Cembrano J, Driesner T, Lizama M, Rowland J, Morata D, Heinrich C A, Tardani D, Campos E, 2016. Physical, chemical and mineralogical evolution of the Tolhuaca geothermal system, southern Andes, Chile: Insights into the interplay between hydrothermal alteration and brittle deformation. J. Volcanol. Geotherm. Res., 324: 88-104. https://doi.org/10.1016/j.jvolgeores.2016.05.009

Smithsonian Institution-SEAN, 1975-89. [Monthly event reports]. Bull Scientific Event Alert Network (SEAN), v 1-14.

Eruptive History

There is data available for 4 confirmed Holocene eruptive periods.

4000 BCE (after) Confirmed Eruption VEI: 0

Episode 1 | Eruption

Pemehue

4000 BCE (after) - Unknown

Evidence from Uncertain

List of 2 Events for Episode 1 at Pemehue

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Lava flow
	- - - -	- - - -	VEI (Explosivity Index)

4885 BCE ± 243 years Confirmed Eruption VEI: 3

Episode 1 | Eruption

4885 BCE ± 243 years - Unknown

Evidence from Uncertain

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	- - - -	- - - -	VEI (Explosivity Index)

5371 BCE ± 243 years Confirmed Eruption VEI: 3

Episode 1 | Eruption

5371 BCE ± 243 years - Unknown

Evidence from Uncertain

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	- - - -	- - - -	VEI (Explosivity Index)

5857 BCE ± 243 years Confirmed Eruption VEI: 3

Episode 1 | Eruption

5857 BCE ± 243 years - Unknown

Evidence from Uncertain

List of 2 Events for Episode 1

	Start Date	End Date	Event Type	Event Remarks
	- - - -	- - - -	Explosion
	- - - -	- - - -	VEI (Explosivity Index)

Deformation History

There is no Deformation History data available for Tolhuaca.

Emission History

There is no Emissions History data available for Tolhuaca.

Photo Gallery

Tolguaca volcano, the snow-capped peak at the left, is a late-Pleistocene to Holocene stratovolcano located immediately NW of Lonquimay volcano. The cinder cone at the right in this view from the SE is the Navidad cone on the NE flank of Lonquimay, which formed during an eruption in 1989. The 2806-m-high Tolguaca is older than its neighbor Lonquimay. It is dissected by glaciers and only fumarolic activity has occurred during historical time. Flank vents are oriented NW-SE, in line with Lonquimay, and SW-NE-trending vents occur on the south flank.

Photo by Norm Banks, 1990 (U.S. Geological Survey).

GVP Map Holdings

Maps are not currently available due to technical issues.

The maps shown below have been scanned from the GVP map archives and include the volcano on this page. Clicking on the small images will load the full 300 dpi map. Very small-scale maps (such as world maps) are not included.

Smithsonian Sample Collections Database

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

External Sites

Copernicus Browser

The Copernicus Browser replaced the Sentinel Hub Playground browser in 2023, to provide access to Earth observation archives from the Copernicus Data Space Ecosystem, the main distribution platform for data from the EU Copernicus missions.

MIROVA

Middle InfraRed Observation of Volcanic Activity (MIROVA) is a near real time volcanic hot-spot detection system based on the analysis of MODIS (Moderate Resolution Imaging Spectroradiometer) data. In particular, MIROVA uses the Middle InfraRed Radiation (MIR), measured over target volcanoes, in order to detect, locate and measure the heat radiation sourced from volcanic activity.

MODVOLC Thermal Alerts

Using infrared satellite Moderate Resolution Imaging Spectroradiometer (MODIS) data, scientists at the Hawai'i Institute of Geophysics and Planetology, University of Hawai'i, developed an automated system called MODVOLC to map thermal hot-spots in near real time. For each MODIS image, the algorithm automatically scans each 1 km pixel within it to check for high-temperature hot-spots. When one is found the date, time, location, and intensity are recorded. MODIS looks at every square km of the Earth every 48 hours, once during the day and once during the night, and the presence of two MODIS sensors in space allows at least four hot-spot observations every two days. Each day updated global maps are compiled to display the locations of all hot spots detected in the previous 24 hours. There is a drop-down list with volcano names which allow users to 'zoom-in' and examine the distribution of hot-spots at a variety of spatial scales.

WOVOdat
   Single Volcano View
   Temporal Evolution of Unrest
   Side by Side Volcanoes

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.

GVMID Data on Volcano Monitoring Infrastructure The Global Volcano Monitoring Infrastructure Database GVMID, is aimed at documenting and improving capabilities of volcano monitoring from the ground and space. GVMID should provide a snapshot and baseline view of the techniques and instrumentation that are in place at various volcanoes, which can be use by volcano observatories as reference to setup new monitoring system or improving networks at a specific volcano. These data will allow identification of what monitoring gaps exist, which can be then targeted by remote sensing infrastructure and future instrument deployments.

Volcanic Hazard Maps

The IAVCEI Commission on Volcanic Hazards and Risk has a Volcanic Hazard Maps database designed to serve as a resource for hazard mappers (or other interested parties) to explore how common issues in hazard map development have been addressed at different volcanoes, in different countries, for different hazards, and for different intended audiences. In addition to the comprehensive, searchable Volcanic Hazard Maps Database, this website contains information about diversity of volcanic hazard maps, illustrated using examples from the database. This site is for educational purposes related to volcanic hazard maps. Hazard maps found on this website should not be used for emergency purposes. For the most recent, official hazard map for a particular volcano, please seek out the proper institutional authorities on the matter.

IRIS seismic stations/networks

Incorporated Research Institutions for Seismology (IRIS) Data Services map showing the location of seismic stations from all available networks (permanent or temporary) within a radius of 0.18° (about 20 km at mid-latitudes) from the given location of Tolhuaca. Users can customize a variety of filters and options in the left panel. Note that if there are no stations are known the map will default to show the entire world with a "No data matched request" error notice.

UNAVCO GPS/GNSS stations

Geodetic Data Services map from UNAVCO showing the location of GPS/GNSS stations from all available networks (permanent or temporary) within a radius of 20 km from the given location of Tolhuaca. Users can customize the data search based on station or network names, location, and time window. Requires Adobe Flash Player.

DECADE Data

The DECADE portal, still in the developmental stage, serves as an example of the proposed interoperability between The Smithsonian Institution's Global Volcanism Program, the Mapping Gas Emissions (MaGa) Database, and the EarthChem Geochemical Portal. The Deep Earth Carbon Degassing (DECADE) initiative seeks to use new and established technologies to determine accurate global fluxes of volcanic CO₂ to the atmosphere, but installing CO₂ monitoring networks on 20 of the world's 150 most actively degassing volcanoes. The group uses related laboratory-based studies (direct gas sampling and analysis, melt inclusions) to provide new data for direct degassing of deep earth carbon to the atmosphere.

Large Eruptions of Tolhuaca

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).

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).