Most Recent Weekly Report: 29 March-4 April 2023 Cite this Report

SERNAGEOMIN reported that increased seismicity at Laguna del Maule was first registered around 1800 on 30 March. The seismic monitoring stations recorded a swarm of 300 volcano-tectonic earthquakes that occurred in an elongated area in a NW-SE direction approximately 10 km SW of the crater at a depth of up 8 km. These events were associated with rock fracturing processes. Starting on 3 April there was an increase in the magnitude of the earthquakes at M 2.5, M 2.8, and M 2.9 at depths of 4.5-8 km. The Alert Level was raised to Yellow, the second lowest on a four-color scale on 3 April.

Source: Servicio Nacional de Geología y Minería (SERNAGEOMIN)

Weekly Reports - Index

2023: March
2021: February | March | December
2020: June | July | September | November

29 March-4 April 2023 Cite this Report

SERNAGEOMIN reported that increased seismicity at Laguna del Maule was first registered around 1800 on 30 March. The seismic monitoring stations recorded a swarm of 300 volcano-tectonic earthquakes that occurred in an elongated area in a NW-SE direction approximately 10 km SW of the crater at a depth of up 8 km. These events were associated with rock fracturing processes. Starting on 3 April there was an increase in the magnitude of the earthquakes at M 2.5, M 2.8, and M 2.9 at depths of 4.5-8 km. The Alert Level was raised to Yellow, the second lowest on a four-color scale on 3 April.

Source: Servicio Nacional de Geología y Minería (SERNAGEOMIN)

22 December-28 December 2021 Cite this Report

SERNAGEOMIN reported that inflation at Laguna del Maule continued in an area SW of the lake during 1-15 December, though deformation had been decreasing since October with a with a maximum rate of 1.88 centimeters per month. Deformation rates during November and December were comparable to those recorded prior to 2019. The number of volcano-tectonic events had also decreased; the largest event was a M 2.3 located 4.1 km ESE from the center of the lake at a depth of 6.1 km. The Alert Level for Laguna del Maule was lowered to Green, the lowest level on a four-color scale, on 24 December. ONEMI canceled the Yellow Alert for San Clemente, and reminded the public to stay 1 km away from the area producing anomalous carbon dioxide emissions, about 5 km SW of the lake’s shore.

Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN); Oficina Nacional de Emergencia-Ministerio del Interior (ONEMI)

17 March-23 March 2021 Cite this Report

SERNAGEOMIN reported that during 1-15 March the seismic network at Laguna del Maule recorded a total of 123 volcano-tectonic earthquakes. The largest event was a local M 2.4 located 8.2 km WSW of the lake, at a depth of 4.4 km. One tremor event was also recorded. Recent carbon dioxide emission measurements showed an upward trend and that the area of anomalous emissions had expanded. Deformation rates were higher than maximum averages. The Alert Level remained at Yellow, the second lowest level on a four-color scale. ONEMI maintained a Yellow Alert for San Clemente and recommended restricted access within a radius of 2 km from the center of elevated carbon dioxide emissions.

Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN); Oficina Nacional de Emergencia-Ministerio del Interior (ONEMI)

17 February-23 February 2021 Cite this Report

SERNAGEOMIN reported that during 1-16 February the seismic network at Laguna del Maule recorded a total of 533 volcano-tectonic earthquakes. Two earthquake swarms were recorded during 15-16 February; the largest events were local magnitude 3.1, and were located 9.1 and 8.8 km SW of the lake at a depth of 1.9 km. The epicenters were near the area producing anomalous carbon dioxide emissions. Swarms were recorded in June and December 2020, and January and February 2021, with the largest events occurring during the most recent swarm.

The highest rate of inflation during the previous 30 days was 2.3 cm/month, recorded at a station closest to the center of deformation. The highest horizontal displacement was an estimated 1.4 cm/month from a station just SW of the center. InSAR data mostly showed agreement in the magnitude and distribution of the ground-based deformation data. Overall, the deformation rates were higher than maximum averages. On 22 February the Alert Level was raised to Yellow, the second lowest level on a four-color scale. ONEMI declared a Yellow Alert for San Clemente and recommended restricted access within a radius of 2 km from the center of elevated carbon dioxide emissions.

Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN); Oficina Nacional de Emergencia-Ministerio del Interior (ONEMI)

4 November-10 November 2020 Cite this Report

SERNAGEOMIN reported that 10 low-magnitude volcano-tectonic earthquakes were detected at the Laguna del Maule Volcanic Complex during 16-31 October; seismicity was low in the region where a swarm had occurred in June. Satellite data showed no deformation, surface changes, gas emissions, or thermal anomalies. On 6 November the Alert Level was lowered to Green, the lowest level on a four-color scale. ONEMI cancelled the Yellow Alert for San Clemente, but declared a “Preventive Early Warning” ensuring continued surveillance of the area and coordination within the Civil Protection System.

Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN); Oficina Nacional de Emergencia-Ministerio del Interior (ONEMI)

23 September-29 September 2020 Cite this Report

SERNAGEOMIN reported that during 1-15 September inflation continued to be detected at the Laguna del Maule Volcanic Complex, although at a lower rate of 0.7 cm per month which is below the 2 cm per month average for this year. Seismicity in the S sector was low in both number and magnitude of events. The Alert Level remained at Yellow, the second lowest color on a four-color scale, as activity remained above baselines. ONEMI recommended restricted access within a radius of 2 km from the emission center.

Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN); Oficina Nacional de Emergencia-Ministerio del Interior (ONEMI)

1 July-7 July 2020 Cite this Report

SERNAGEOMIN reported that, although the number and magnitude of earthquakes had decreased during 20-30 June, seismicity at the Laguna del Maule Volcanic Complex continued to remain anomalously elevated at east through 7 July. The location of the activity remained within an area about 5 km in diameter, near the intersection of two faults near Las Nieblas, and corresponded to elevated levels of carbon dioxide emissions. The Alert Level remained at Yellow, the second lowest color on a four-color scale; ONEMI recommended restricted access within a radius of 2 km from the emission center.

Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN); Oficina Nacional de Emergencia-Ministerio del Interior (ONEMI)

17 June-23 June 2020 Cite this Report

SERNAGEOMIN’s Volcanological Observatory of the Southern Andes (OVDAS) of Chile and SEGEMAR’s Argentine Observatory of Volcanic Surveillance (OAVV) reported anomalous activity at Laguna del Maule Volcanic Complex. Elevated levels of carbon dioxide were detected in an area SW of the caldera lake, along the lower part of the Cabecera de Troncoso River, about 5 km from the lake’s shore. Carbon dioxide emissions were measured in February 2020 and notably elevated relative to March 2019 measurements. An impacted area possibly stretched as far as 500 m from the point representing the highest carbon dioxide emission rate; observers noted areas of discolored brown and orange soil aonlg with dead or emaciated animals.

Three swarms of volcano-tectonic (VT) earthquakes recorded in mid-June were mainly located in the Las Nieblas area, SW of the lake, at depths of 2-8 km. The first began at 0340 on 11 June and totaled at least 400 events. The second swarm began at 2338 on 12 June was characterized by 121 events, located 8.8 km W of the crater. The third swarm began at 2334 on 15 June and was characterized by 190 events located 10.4 km SW of the crater. All of the earthquakes were small magnitudes; the largest event was a local M 2.5. On 18 June the Alert Level was raised to Yellow, the second lowest color on a four-color scale; ONEMI recommended restricting access within a radius of 2 km from the emission center. Seismic activity continued to be recorded, though at lesser magnitudes.

Sources: Servicio Nacional de Geología y Minería (SERNAGEOMIN); Servicio Geológico Minero Argentino (SEGEMAR); Oficina Nacional de Emergencia-Ministerio del Interior (ONEMI)

The Global Volcanism Program has no Bulletin Reports available for Laguna del Maule.

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.

Cones
Feature Name	Feature Type	Elevation	Latitude	Longitude
Barrancas, Cerro	Cone	3092 m	36° 10' 18" S	70° 26' 50" W
Bobadilla, Crater	Cone
Candado, El	Cone	2367 m	36° 0' 45" S	70° 33' 40" W
Portillo, Volcán el	Cone	2890 m	36° 12' 0" S	70° 35' 0" W
Saso, Volcán	Cone		36° 6' 0" S	70° 43' 0" W
Craters
Feature Name	Feature Type	Elevation	Latitude	Longitude
Laguna del Maule	Caldera	2165 m	36° 3' 0" S	70° 30' 0" W
Negra, Crater	Crater	2432 m	36° 4' 20" S	70° 33' 45" W
Domes
Feature Name	Feature Type	Elevation	Latitude	Longitude
Baños, Crateres de los     Colada Dendriforme	Dome	2654 m	36° 3' 10" S	70° 33' 0" W
Cari-Launa, Volcanes	Dome	3049 m	36° 3' 0" S	70° 25' 0" W
Colada las Nieblas	Dome	2563 m	36° 7' 0" S	70° 32' 0" W
Colada Occidental	Dome	2517 m	36° 1' 20" S	70° 35' 30" W
Divisoria	Dome	3051 m	36° 4' 52" S	70° 25' 2" W
Espejos, Loma de los	Dome	2463 m	36° 0' 0" S	70° 32' 0" W
Maule, Domos del	Dome	2556 m	36° 1' 45" S	70° 34' 35" W

Basic Data Volcano Number Last Known Eruption Elevation Latitude Longitude 357061 50 BCE 2,162 m / 7,093 ft 36.058°S 70.492°W Morphology Volcano Landform Caldera Volcano Types Caldera Stratovolcano(es) Lava dome(s) Pyroclastic cone(s) Rock Types Major Andesite / Basaltic Andesite Rhyolite Basalt / Picro-Basalt Dacite Tectonic Setting Subduction zone Continental crust (> 25 km) Population Within 5 km Within 10 km Within 30 km Within 100 km 1,045 1,045 1,521 169,334

Geological Summary The Laguna del Maule volcanic complex includes a 15 x 25 km caldera with a cluster of small stratovolcanoes, lava domes, and pyroclastic cones of Pleistocene-to-Holocene age. The caldera lies mostly on the Chilean side of the border, but partially extends into Argentina. Fourteen Pleistocene basaltic lava flows were erupted down the upper part of the Maule river valley. A cluster of Pleistocene cinder cones was constructed on the NW side of Maule lake in the northern part of the caldera. The latest activity produced an explosion crater on the E side of the lake and a series of Holocene rhyolitic lava domes and blocky lava flows that surround it. References The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography. Drake R E, 1976. Chronology of Cenozoic igneous and tectonic events in the central Chilean Andes-latitudes 35.5 to 36° S. J. Volcanol. Geotherm. Res., 1: 265-284. Frey F A, Gerlach D C, Hickey R L, Lopez-Escobar L, Munizaga-Villavicencio F, 1984. Petrogenesis of the Laguna del Maule volcanic complex, Chile (36°). Contr Mineral Petr, 88: 133-149. Gonzalez-Ferran O, 1995. Volcanes de Chile. Santiago: Instituto Geografico Militar, 635 p. Gonzalez-Ferran O, Vergara M, 1962. Reconocimiento geologico de la Cordillera de los Andes entre los paralelos 35° y 38° latitud sur. Chile Univ Inst Geol Pub, 24: 1-121. Hildreth W, Drake R, Godoy E, Munizaga F, 1991. Bobadilla caldera and 1.1 Ma ignimbrite at Laguna del Maule, Southern Chile.. VI Congreso Geológico Chileno, Abs, p 62-63. IAVCEI, 1973-80. Post-Miocene Volcanoes of the World. IAVCEI Data Sheets, Rome: Internatl Assoc Volc Chemistry Earth's Interior. 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, Naranjo J A, 1991. The southern Andes volcanoes (33°-41° 30' S), Chile. 6th Geol Cong Chile, Excur PC-3, 26 p. Singer B S, Andersen N L, Le Mevel H, Feigl K L, DeMets C, Tikoff B, Thurber C H, Jicha B R, Cardona C, Cordova L, Gil F, Unsworth M J, Williams-Jones G, Miller C, Fierstein J, Hildreth W, Vazquez J, 2014. Dynamics of a large, restless, rhyolitic magma system at Laguna del Maule, southern Andes, Chile. GSA Today, v. 24, no. 12. https://doi.org/10.1130/GSATG216A.1

Eruptive History

There is data available for 4 confirmed Holocene eruptive periods.

Deformation History

There is data available for 1 deformation periods. Expand each entry for additional details.

Emission History

There is no Emissions History data available for Laguna del Maule.

Photo Gallery

Pyroclastic cones and lava flows at the NW side of the Laguna del Maule volcanic center rise above the shore of the lake. This cluster of small stratovolcanoes, lava domes, and pyroclastic cones covers an area of 15 x 20 km within a Pleistocene caldera. Pleistocene and Holocene basaltic lava flows were erupted down the upper part of the Maule River valley and on all sides of the lake.

Photo by Oscar González-Ferrán (University of Chile).

GVP Map Holdings

Maps are not currently available due to technical issues.

Smithsonian Sample Collections Database

The following 5 samples associated with this volcano can be found in the Smithsonian's NMNH Department of Mineral Sciences collections, and may be availble for research (contact the Rock and Ore Collections Manager). Catalog number links will open a window with more information.

Catalog Number	Sample Description	Lava Source	Collection Date
NMNH 117456-11	Perlite	--	--
NMNH 117456-12	Obsidian	--	--
NMNH 117456-13	Obsidian	--	--
NMNH 117456-14	Obsidian	--	--
NMNH 117456-21	Obsidian	--	--

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 Laguna del Maule. 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 Laguna del Maule. 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 Laguna del Maule	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).