Guagua Pichincha Volcano | John Seach

john

Ecuador

0.171 S, 78.598 W
summit elevation 4784 m
Stratovolcano

Guagua Pichincha Volcano is located 8 km from the centre of Quito, the capital of Ecuador. The volcano is 23 km in diameter. Historical activity of the volcano has included large explosive eruptions which has produced Plinian columns, dome growth, and pyroclastic flows.

Pichincha Volcanic Complex consists of an extinct older volcano (Rucu Pichincha), and a younger active volcano (Guagua Pichincha). Since 1981, Guagua Pichincha volcano has begun a new phase of low seismic, phreatic and magmatic activity after being dormant for 100 years.

2008 Eruptions
Seven phreatic eruptions occurred at Guagua Pichincha Volcano on 1st February 2008. The eruptions were preceded by a magnitude 4.1 earthquake on 6th December 2007.

Possible eruption in 2003
On 17th April 2003, seismic signals indicating a possible minor eruption at Guagua Pichincha, but there were no visual signs of an eruption.

2002 Eruptions
On 11th October 2002 four phreatic eruptions occurred after several days of heavy rainfall. The eruption ejected blocks 100-200 m from the vent. Long-period and volcano-tectonic earthquakes and continuous background tremor were recorded until 17th October.

2001 Eruption
Ash emissions on 18th, 31st March, and 25th May. The May eruption sent ash to a height of 8.5 km. On 26th November 2001, seismic recording indicated that a 20 minute-long phreatic explosion began around midday. This was followed by 16 hours of continuous tremor.

2000 Eruption and Fatalities
A phreatic explosion at 1146 on 12th March, 2000 in the crater of Guagua Pichincha's central dome killed two volcanologists. A warning of possible activity had been transmitted to them by radio at 1030, but for unknown reasons they were still on the dome when the eruption occurred.

1998 Eruptions
In August 1998 phreatic eruptions occurred daily to weekly approximately one year.

1981 Eruptions
Eruptions began in 1981 with phreatic activity that produced ash explosions and an increase in fumarole gas emission. This was the first eruptions in 100 years at the volcano.

1660 Eruption
An eruption began at Guagua Pichincha volcano on 28th October 1660 and laster for 12 hours. A plinian column deposited ash and pumice over Quito, and plunged the city into darkness. Pyroclastic flows and surges overrode the southern and eastern rims of the crater. The topographic relief of Rucu Pichincha prevented flows from reaching Quito. Ash fell as far north as Popayan, Columbia (300 km ), south at Loja (430 km ), and west at the Pacific coast ( 170 km). Earthquakes associated with the eruption caused panic in Quito. No casualties were reported, but the eruption caused significant economic loss to the surrounding region.

Further reading
Monzier, Miehel, et al. "Evolution of the Pichincha volcanic complex (Ecuador)." Proceedings of fifth international symposium on Andean geodynamics, Toulouse. 2002.

Barberi, F., et al. "Volcanic hazard assessment of Guagua Pichincha (Ecuador) based on past behaviour and numerical models." Journal of volcanology and geothermal research 49.1-2 (1992): 53-68.

Marini, L., et al. "Guagua Pichincha volcano, Ecuador: fluid geochemistry in volcanic surveillance." Journal of Volcanology and Geothermal Research 46.1-2 (1991): 21-35.

Guagua Pichincha Volcano Eruptions

2009, 2008, 2003, 2002, 2001, 1998-2000, 1997, 1993, 1990, 1985, 1981-82, 1881, 1869, 1868, 1831, 1830, 1660, 1582-98, 1580?, 1577?, 1575, 1566, 1560?, 1539?, 1538?, 1535?, 1534?, 1533?.