|Night view of one of many explosive events at Tungurahua Volcano, Ecuador, that occurred during the continuous extrusion of lava in the summit crater in November and December. In this time-lapse photograph, glowing lava fragments can be seen blasting into the air and falling onto the upper flanks of the volcano. Photo Credit: Alcinoe Calahorrano on November 2, 1999|
Tungurahua is an active stratovolcano also known as the "The Black Giant." It is a steep-sided andesitic-dacitic stratovolcano that towers more than 3 km above its northern base, is one of Ecuador's most active volcanoes. Three major volcanic edifices have been sequentially constructed since the mid-Pleistocene over a basement of metamorphic rocks. Tungurahua II was built within the past 14,000 years following the collapse of the initial edifice. Tungurahua II itself collapsed about 3000 years ago and produced a large debris-avalanche deposit and a horseshoe-shaped caldera open to the west, inside which the modern glacier-capped stratovolcano (Tungurahua III) was constructed. Historical eruptions have all originated from the 600 ft. (183 m) wide summit crater. They have been accompanied by strong explosions and sometimes by pyroclastic flows and lava flows that reached populated areas at the volcano's base.
Eruption at Tungurahua - Image courtesy of (and for more great photo's of Ecuador) ECUADOR 365.
Tungurahua causes many tremors in the nearby city of Banos. Tungurahua's lava is mostly composed of basalts. Tungurahua has had at least seventeen eruptions in historical times Prior to a long-term eruption beginning in 1995 that caused the temporary evacuation of the city of Ba�os at the foot of the volcano, the last major eruption had occurred from 1916 to 1918, although minor activity continued until 1925.
Smoke rising from Tungurahua (right)
Image credit: DJ Harris
Sources of Information:
Dyott, G.M., "The Volcanoes of Ecuador, Guideposts in Crossing South America," National Geographic, pp. 49-93, January, 1929.
Simkin, Tom and Siebert, Lee, "Volcanoes of the World," Geoscience Press, Tuscon, AZ, 349 pp., 1994.