Tungurahua, Ecuador

Tungurahua is an active stratovolcano also known as the "The Black Giant." It has a 600 ft. (183 m) wide crater. Most of the volcano is covered by snow. Its 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, its most recent occurring in 1944 when it erupted explosively from its central crater. Located about 25 miles (~40 km) west of Tungurahua is the largest volcano in Equador, Chimborazo and to the north about 50 miles(~80 km ) is Cotopaxi volcano.

November 10, 1999

Explosions of ash and incandescent materials occur 25-35 times per day and a column of ash and gases is present at all times. The outflow of sulphur dioxide registered during the past few days has reached levels between eight and ten thousand metric tons per day. Explosions continue to grow in magnitude and are accompanied by loud bangs that can be heard as far as 20 km away. Mud flows have destroyed several segments of the road between Banos and Pinipe. Volcanic ash has affected ~50,000 hectares of farm land.

November 8, 1999

On 4 November, an ash cloud erupted from the Tungurahua Volcano. The ash cloud rose approximately 30,000 feet (9 km) above sea level.

November 4, 1999

On 1 November, the Tungurahua Volcano erupted at 1245 UTC, and the ash plume rose 35,000 ft. (10.7 km) into the air.

October 26, 1999

On 23 October, the Tungurahua Volcano sent out a mushroom-shaped column of ash and gas 32,800 feet (~10 km) above the volcano's crater.

October 21, 1999

On 18 October, the Geophysical Institute of Ecuador reported that the Tungurahua Volcano continues to show increasingly vigorous activity. Tremor saturates the seismic records. There are high levels of gas emissions. A volcano-tectonic earthquake was recorded on the 18th at a depth of 4.3 km. Continuous ash clouds are rising above the summit with ashfalls. On 19 October, a new eruptive espisode, occurred and ash clouds rose to 25,000 feet (~8 km).

A total of 22,000 people have been evacuated from the area surrounding the Tungurahua Volcano. Measures are being taken to protect the Agoyan hydroelectic power plant located on the Pastaza River.

October 19, 1999

On 17 October, the Tungurahua Volcano alert level was raised to ORANGE. Volcanic tremor is so strong as to mask other seismic signals. Incandescent tephra has fallen on the W flank. The crater has become enlarged on a N-S axis, and a stream of gas and ash continues to rise from the crater. Very high sulphur dioxide S02 levels have been measured. Inclinometers have detected signs of cone deformation. On 18 October, the Tungurahua Volcano covered the surrounding areas with a blanket of ash. The towns of Banos, Pinipe, Puela, and Bilboa have been evacuated. An appeal for international disaster assistance has been requested by the Minister of Housing and Urban Development. Authorities expect this emergency will last 20 months.

October 18, 1999

On 16 October, the Government of Ecuador reported that the Tungurahua Volcano could erupt any day and began evacuating nearby communities. Officials said at least 12,000 of the 25,000 people threatened by an eruption have already left the area. The volcano has been expelling gases, steam, and ash for several days. Experts have calculated there is an 80% chance the volcano will erupt. Lava could flow over a ridge into parts of Banos, a town famed for its hot springs and mountain trekking. Tungurahua means "Throat of Fire" in the Quechua Indian language.

October 13, 1999

On the morning of 11 October, ash colums rose to 500 m. A 11 October report indicated that a strong continuous tremor is blanking all other seismic signal. Slight but continuous ashfalls to the W are now being reported.

October 12, 1999

On October, there were three phreatic explosions. Sulfur dioxide emissions increased to values between 9,000 to 10,000 MT per day and dropped to ~6,000 MT per day on 7 October. On 7 October, the Civil Defense met with participants from international and diplomatic missions. International cooperation was requested.

October 6, 1999

On 5 October, the Tungurahua Volcano sent up an explosion of gases. Three mountain climbers and their guide were injured. The Civil Defense has activiated emergency operations and contingency plans are now being put into place. The Tungurahua Volcano is very restless with long period and hybrid earthquakes, as well as harmonic tremor.

September 30, 1999

Numerous phreatic eruptions per day are occurring at the Tungurahua Volcano. Magma may be rising in the in the column. SO2 flux of nearly 7,000 tons/day are being reported.