According to INGEOMINAS, the Observatorio Vulcanológico and Sismológico de Popayán reported that during 8-14 August seismic activity at Sotará increased. The seismic network recorded 110 magnitude 0.2-1.6 events mainly located in an area 0.1-5 km NE of the peak, at depths of 2-6 km. Inflation was detected in the NE area, coincident with the zone of increased seismicity. Web-camera views showed no morphological changes. The Alert Level was raised to III (Yellow; "changes in the behavior of volcanic activity"), or the second lowest level.
Source: Servicio Geológico Colombiano (SGC)
Monitoring efforts and recent seismic unrest
Sotará is considered a recently-active volcano within the Sotará volcanic complex described by the Instituto Colombiano de Geología y Minería (INGEOMINAS) as a caldera with resurgent volcanism. Two volcanoes developed within the caldera, Sotará in the center and Cerro Gordo on the S edge (figure 1). Two smaller volcanic peaks, Cerro Negro and Cerro Azafatudo, have been identified on the NW flank of the caldera and described as pre-Sotará features. Monitoring efforts by INGEOMINAS's Popayán Observatory, beginning in 1993, documented persistent seismicity, active fumarolic sites, and thermal springs. Historic eruptions (within 500 years) have not been observed from this complex.
Expanded monitoring efforts. The INGEOMINAS observatory based in Popayán (37 km NW of Sotará) began monitoring volcanic activity at Sotará in 1993. A seismic station was installed on the NE flank of the volcano that year and in 1995, significant seismicity was detected by that station. A temporary seismic station was added to the area in 1995 and by 2007, the monitoring network was expanded with permanent stations. In August 2012 the network contained eight geophysical stations that included short period and broadband seismic stations, electronic tiltmeters, a webcamera, and electronic distance meter (EDM) measuring sites (reflectors and benchmarks) (figure 2).
Since monitoring began in 1993, the largest earthquake that occurred in this region had a local magnitude (ML) of 4.4 with an epicenter 16 km NW of Sotará. INGEOMINAS recorded the event at 1537 (local time) on 6 June 2010 with a focal depth at 6.9 km. The shaking caused by this earthquake was reported in six communities located as far as 20 km N of the epicenter. There were five aftershocks with magnitudes ranging 0.5-2.6. One of these aftershocks, occurring at 1555, was felt in two towns, Chapa and Coconuco (located 5.5 km NW and 15 km N of the epicenter, respectively). The last aftershock (ML 2.4) was recorded on 7 June with a 6-km focal depth and epicenter 22.7 km NW of the volcano.
INGEOMINAS reported low levels of seismicity from January 2010 through May 2012 (table 1). Volcano-tectonic (VT) earthquakes occurred more frequently than long period (LP) events or events interpreted as rockfalls (RF). VT hypocenters were calculated for 1-14 earthquakes per month except during October 2011, when 50 VT events were located within the Paletará Valley (see subsection Paletará Valley seismicity for details). From 2010 through May 2012, local magnitudes were rarely greater than 2.
Paletará Valley seismicity. Beginning in January 2010, INGEOMINAS reported earthquakes frequently occurring within the Paletará Valley. In a roughly circular region ~5 km in diameter, VT earthquakes clustered at a distance 15-25 km NE from Sotará's edifice (figure 3). Many of these events were too small to locate (ML
In 2011, relatively large earthquakes were detected in October and December within Paletará Valley. INGEOMINAS reported elevated seismicity that began on 14 October at 1423. Low magnitude events, characterized as rockfalls, were also recorded on 14 October. Over the next 24 hours, ~38 earthquakes were recorded and by the end of the month, 54 VT earthquakes were registered with epicenters within ~7-10 km NE of Sotará. Local magnitudes ranged from 0.1-2.7. INGEOMINAS announced in a 15 October assessment that seismicity had not affected the Sotará volcanic system and communities located near the volcano were not at risk.
On 18 December 2011 at 0902 an ML 3.2 earthquake was detected by the INGEOMINAS seismic network. The epicenter was 21 km SW of Sotará and 17.5 km deep. Shaking was reported in the town of La Vega located ~20 km W of Sotará.
Seismic unrest in 2012. In early 2012, ~6 earthquakes were located per month and epicenters tended to cluster NE of the edifice (table 1). In April 2012, several earthquakes also appeared ~10 km SW of Sotará. From January through May 2012, VT earthquakes (no LPs occurred) were shallow (0.5-2 km), however, due to small magnitudes (ML 0.5-2.1), the events did not cause noticeable shaking in local communities.
In their June 2012 technical bulletin, INGEOMINAS noted increased seismicity clustered within 4 km NE of the summit. Local seismic stations detected 744 events and located 120 events classified as VTs. Epicenters were clustered in an elongate region striking 3 km NE. Local magnitudes ranged between -0.5-2.0 with depths ranging 2-6 km.
Seismicity decreased by 30 June; however, on 25 July, numerous VT events were registered. By 31 July, 1,232 VT earthquakes had been detected (575 of which were located), 2,295 events were detected but not classified, and nine LP events were detected. Epicenters were dispersed in a larger zone NE of the summit, however, magnitudes and depths were similar to those detected during the previous month.
A site visit conducted by INGEOMINAS in July included the NW sector of Sotará where hot springs were located. Investigators measured temperatures and assessed the geochemistry of the springs and determined that no significant changes had occurred.
Increased seismicity persisted in early August 2012 and by 8 August, INGEOMINAS reported that, on average, 150 earthquakes were occurring per day (figure 4). In a special bulletin, INGEOMINAS assessed the seismicity and also highlighted new conclusions from the tiltmeter network. They noted that from January 2010 through July 2012, no deformation was detected by the electronic tiltmeters. By early August 2012, an inflation trend was detected in the NE sector that was potentially linked to the cluster of earthquakes in the immediate area. No significant trends were interpreted from the SW sector. On 8 August 2012, INGEOMINAS announced that the Alert Level was raised to III (Yellow; "changes in the behavior of volcanic activity"), or the second lowest level.
INGEOMINAS continued to monitor Sotará closely from September through early October 2012 and noted decreasing seismicity. Fewer earthquakes were registered (22-100 VTs) and magnitudes ranged 0.1-1.6. Clear images captured by the local webcamera (located 3 km NW) showed no morphological changes (figure 5).
References. Cediel, F., Shaw, R.P., and Cáceres, C., 2003, Tectonic assembly of the Northern Andean Block, in C. Bartolini, R.T. Buffler, and J. Blickwede, eds., The Circum-Gulf of Mexico and the Caribbean: Hydrocarbon habitats, basin formation, and plate tectonics: AAPG Memoir 79, p. 815-848.
Page, W.D., 1983, Popayán earthquake of 31 March 1983 geologic and seismologic aspects, Woodward Clyde Consultants, San Francisco Area Office, Walnut Creek, CA, USA, p. 51-59.
Information Contacts: Instituto Colombiano de Geologia y Mineria (INGEOMINAS), Observatorio Vulcanológico y Sismológico de Popayán, Popayán, Colombia.
2012: August
According to INGEOMINAS, the Observatorio Vulcanológico and Sismológico de Popayán reported that during 8-14 August seismic activity at Sotará increased. The seismic network recorded 110 magnitude 0.2-1.6 events mainly located in an area 0.1-5 km NE of the peak, at depths of 2-6 km. Inflation was detected in the NE area, coincident with the zone of increased seismicity. Web-camera views showed no morphological changes. The Alert Level was raised to III (Yellow; "changes in the behavior of volcanic activity"), or the second lowest level.
Source: Servicio Geológico Colombiano (SGC)
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.
Monitoring efforts and recent seismic unrest
Sotará is considered a recently-active volcano within the Sotará volcanic complex described by the Instituto Colombiano de Geología y Minería (INGEOMINAS) as a caldera with resurgent volcanism. Two volcanoes developed within the caldera, Sotará in the center and Cerro Gordo on the S edge (figure 1). Two smaller volcanic peaks, Cerro Negro and Cerro Azafatudo, have been identified on the NW flank of the caldera and described as pre-Sotará features. Monitoring efforts by INGEOMINAS's Popayán Observatory, beginning in 1993, documented persistent seismicity, active fumarolic sites, and thermal springs. Historic eruptions (within 500 years) have not been observed from this complex.
Expanded monitoring efforts. The INGEOMINAS observatory based in Popayán (37 km NW of Sotará) began monitoring volcanic activity at Sotará in 1993. A seismic station was installed on the NE flank of the volcano that year and in 1995, significant seismicity was detected by that station. A temporary seismic station was added to the area in 1995 and by 2007, the monitoring network was expanded with permanent stations. In August 2012 the network contained eight geophysical stations that included short period and broadband seismic stations, electronic tiltmeters, a webcamera, and electronic distance meter (EDM) measuring sites (reflectors and benchmarks) (figure 2).
Since monitoring began in 1993, the largest earthquake that occurred in this region had a local magnitude (ML) of 4.4 with an epicenter 16 km NW of Sotará. INGEOMINAS recorded the event at 1537 (local time) on 6 June 2010 with a focal depth at 6.9 km. The shaking caused by this earthquake was reported in six communities located as far as 20 km N of the epicenter. There were five aftershocks with magnitudes ranging 0.5-2.6. One of these aftershocks, occurring at 1555, was felt in two towns, Chapa and Coconuco (located 5.5 km NW and 15 km N of the epicenter, respectively). The last aftershock (ML 2.4) was recorded on 7 June with a 6-km focal depth and epicenter 22.7 km NW of the volcano.
INGEOMINAS reported low levels of seismicity from January 2010 through May 2012 (table 1). Volcano-tectonic (VT) earthquakes occurred more frequently than long period (LP) events or events interpreted as rockfalls (RF). VT hypocenters were calculated for 1-14 earthquakes per month except during October 2011, when 50 VT events were located within the Paletará Valley (see subsection Paletará Valley seismicity for details). From 2010 through May 2012, local magnitudes were rarely greater than 2.
Paletará Valley seismicity. Beginning in January 2010, INGEOMINAS reported earthquakes frequently occurring within the Paletará Valley. In a roughly circular region ~5 km in diameter, VT earthquakes clustered at a distance 15-25 km NE from Sotará's edifice (figure 3). Many of these events were too small to locate (ML
In 2011, relatively large earthquakes were detected in October and December within Paletará Valley. INGEOMINAS reported elevated seismicity that began on 14 October at 1423. Low magnitude events, characterized as rockfalls, were also recorded on 14 October. Over the next 24 hours, ~38 earthquakes were recorded and by the end of the month, 54 VT earthquakes were registered with epicenters within ~7-10 km NE of Sotará. Local magnitudes ranged from 0.1-2.7. INGEOMINAS announced in a 15 October assessment that seismicity had not affected the Sotará volcanic system and communities located near the volcano were not at risk.
On 18 December 2011 at 0902 an ML 3.2 earthquake was detected by the INGEOMINAS seismic network. The epicenter was 21 km SW of Sotará and 17.5 km deep. Shaking was reported in the town of La Vega located ~20 km W of Sotará.
Seismic unrest in 2012. In early 2012, ~6 earthquakes were located per month and epicenters tended to cluster NE of the edifice (table 1). In April 2012, several earthquakes also appeared ~10 km SW of Sotará. From January through May 2012, VT earthquakes (no LPs occurred) were shallow (0.5-2 km), however, due to small magnitudes (ML 0.5-2.1), the events did not cause noticeable shaking in local communities.
In their June 2012 technical bulletin, INGEOMINAS noted increased seismicity clustered within 4 km NE of the summit. Local seismic stations detected 744 events and located 120 events classified as VTs. Epicenters were clustered in an elongate region striking 3 km NE. Local magnitudes ranged between -0.5-2.0 with depths ranging 2-6 km.
Seismicity decreased by 30 June; however, on 25 July, numerous VT events were registered. By 31 July, 1,232 VT earthquakes had been detected (575 of which were located), 2,295 events were detected but not classified, and nine LP events were detected. Epicenters were dispersed in a larger zone NE of the summit, however, magnitudes and depths were similar to those detected during the previous month.
A site visit conducted by INGEOMINAS in July included the NW sector of Sotará where hot springs were located. Investigators measured temperatures and assessed the geochemistry of the springs and determined that no significant changes had occurred.
Increased seismicity persisted in early August 2012 and by 8 August, INGEOMINAS reported that, on average, 150 earthquakes were occurring per day (figure 4). In a special bulletin, INGEOMINAS assessed the seismicity and also highlighted new conclusions from the tiltmeter network. They noted that from January 2010 through July 2012, no deformation was detected by the electronic tiltmeters. By early August 2012, an inflation trend was detected in the NE sector that was potentially linked to the cluster of earthquakes in the immediate area. No significant trends were interpreted from the SW sector. On 8 August 2012, INGEOMINAS announced that the Alert Level was raised to III (Yellow; "changes in the behavior of volcanic activity"), or the second lowest level.
INGEOMINAS continued to monitor Sotará closely from September through early October 2012 and noted decreasing seismicity. Fewer earthquakes were registered (22-100 VTs) and magnitudes ranged 0.1-1.6. Clear images captured by the local webcamera (located 3 km NW) showed no morphological changes (figure 5).
References. Cediel, F., Shaw, R.P., and Cáceres, C., 2003, Tectonic assembly of the Northern Andean Block, in C. Bartolini, R.T. Buffler, and J. Blickwede, eds., The Circum-Gulf of Mexico and the Caribbean: Hydrocarbon habitats, basin formation, and plate tectonics: AAPG Memoir 79, p. 815-848.
Page, W.D., 1983, Popayán earthquake of 31 March 1983 geologic and seismologic aspects, Woodward Clyde Consultants, San Francisco Area Office, Walnut Creek, CA, USA, p. 51-59.
Information Contacts: Instituto Colombiano de Geologia y Mineria (INGEOMINAS), Observatorio Vulcanológico y Sismológico de Popayán, Popayán, Colombia.
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 |
Azafatudo, Cerro |
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The Global Volcanism Program is not aware of any Holocene eruptions from Sotará. If this volcano has had large eruptions (VEI >= 4) prior to 12,000 years ago, information might be found on the Sotará page in the LaMEVE (Large Magnitude Explosive Volcanic Eruptions) database, a part of the Volcano Global Risk Identification and Analysis Project (VOGRIPA).
There is no Deformation History data available for Sotará.
There is no Emissions History data available for Sotará.
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.
There are no samples for Sotará in the Smithsonian's NMNH Department of Mineral Sciences Rock and Ore collection.
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 Sotará. 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 Sotará. 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 Sotará | 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). |