Thank you to Chryphia and Renato Rio for finding lots of information on Tungurahua, including the Instituto Geofísico Escuela Politécnica Nacional (IGEPN)’s excellent website.
Tungurahua woke nearby residents with an explosive eruption at 11:51 UTC (06:51 am local time) on Sunday 14 July 2013 (VA report ). The eruption could be heard as far away as Guayaquil . The initial eruption column reached an altitude of 5.1km. A few hours later the column was observed to have reached 8.3 km. The ash cloud drifted northwest, north and northeast of the volcano. Pyroclastic flows were produced, including one down the ravine of Achupashal on the west side of the volcano. Ash fell on towns close to the volcano.Here is the seismogram showing the onset of the eruption:
About TungurahuaTungurahua (5,023m) is an andesitic-dactitic stratovolcano located in the Cordillera Real in the Andes Mountains, Ecuador. The Cordillera Real lies in the Northern Volcanic Zone of Andean Volcanic Belt. The subduction of the Nazca Plate under the South American Plate is responsible for volcanic activity in the region and also the Andean orogeny. Tungurahua is one of Ecuador’s most active volcanoes, having produced several eruptions in the order of VEI-3 to VEI-4, and one eruption of VEI-5, according to GVP . The VEI 5 in 1010 BC destroyed the edifice. A smaller eruption in 1641 is believed to have destroyed the village of Cacha and its 5,000 inhabitants. Other significant recent eruptions occurred in 1773, 1886 and 1916-1918.
Tungurahua has a history of building followed by edifice collapse. The current edifice (Tungurahua III) is located within the caldera created by the collapse 3,000 years ago of Tungurahua II. The collapse also created a large debris avalanche deposit.
Eruptions are explosive generating ash, pumice, scoria, pyroclastic flows, lava flows (which have reached nearby populated areas), lava lakes and lahars. There have also been some property damage and fatalities.
More information can be found on IGEPN’s website and GVP.
Update: As of editing this in the tremor is rising within the volcanic system.
- VA report: http://www.ssd.noaa.gov/VAAC/ARCH13/TUNG/2013G141243.html
- IGEPN webcams: http://www.igepn.edu.ec/volcanes/camaras-de-volcanes.html
- IGEPN Helicorders: http://www.igepn.edu.ec/index.php/sismos/senalessismicas.html
4. Image Photo by Martin Zeise, Berlin, http://upload.wikimedia.org/wikipedia/commons/d/d1/Equador_Tungurahua.JPG
5. Map by Chiton Magnificus http://upload.wikimedia.org/wikipedia/commons/a/a7/MAGMAARC1.jpg
6. Map of volcanoes in Ecuador from http://en.wikipedia.org/wiki/Tungurahua
7. Nazca Plate from USGS: http://pubs.usgs.gov/publications/text/slabs.html
8. GVP: http://www.volcano.si.edu/volcano.cfm?vn=352080
9. IGPEN: http://www.igepn.edu.ec/
10. Wikipedia: http://en.wikipedia.org/wiki/Andean_Volcanic_Belt