Chaitén (volcano)
| Chaitén | ||
|---|---|---|
 The caldera is in the lower right corner, the place Chaitén on the coast, to the south. |
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| height | 1122 m | |
| location | Región de los Lagos ( Region X), Chile | |
| Mountains | To the | |
| Coordinates | 42 ° 49 '58 " S , 72 ° 38' 45" W | |
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| Type | Caldera | |
| Last eruption | 2008-2013 | |
The Chaitén is a 1122 m high volcano in the Andes Patagonia in the south of Chile . It is located ten kilometers northeast of the small coastal town of the same name, Chaitén, in the volcanically very active area of the South American Cordillera . Its summit caldera has a maximum diameter of 3.53 kilometers and is almost completely filled with lava domes consisting of rhyolite and obsidian rocks . By the eruption in 2008, these domes reached a height of 962 meters above sea level and were partially overgrown with vegetation. Inside the caldera on the edge of the lava domes there were also two small lakes, one on the west and one on the north side.
According to a radiocarbon dating of the last lava flow, the penultimate eruption had occurred approximately 9450 years ago. The last eruptions took place more or less continuously from 2008 to 2011. The eruption has been over since 2013.
2008 eruption
On May 2, 2008, Chaitén, who had already been thought to be extinct, suddenly broke out again. An ash cloud up to 20 kilometers high rose over the crater and within four days more than 60 volcanic earthquakes were triggered.
Due to some pyroclastic flows that were triggered by the partial demolition of the lava dome and in anticipation of a larger explosive eruption, the national Chilean civil protection authority has issued the highest level of alert for the affected region and the Chilean government declared the area around the volcano a disaster area. Only a few hours after the beginning of the eruptions, due to the persistent heavy ash rain, work began to bring the first residents to safety. In the village of the same name, Chaitén, a fine layer of ash about 15 centimeters high was deposited, which led to numerous water supplies being contaminated. From May 3rd to 5th, the 3300 residents of Chaitén and 700 others from the immediate vicinity were evacuated. However, one older woman was killed.
On May 4th, Chilean President Michelle Bachelet and some of her ministers visited the affected area and found out about the security measures. The following day, she and her team flew over the volcano to the village of Futaleufú, 75 kilometers southeast of the mountain (not to be confused with the Argentine department of Futaleufú ) and attended the evacuation of 1,000 people there. This had become necessary because the wind had fanned out the ash cloud. It had already moved in a south-easterly direction across the entire breadth of Patagonia and reached the coast of the Atlantic Ocean , 660 kilometers away . Due to this expansion, massive ash rains also occurred in Argentina. The eruptions continued for the rest of the year and as they progressed, several lava domes formed in the volcano's crater , the youngest of which reached a height of 120 meters. On February 19, 2009, it collapsed in parts, causing a five-kilometer pyroclastic flow that poured into the valley of the Chaitén River. On that day, 135 of the last 160 remaining residents of Chaitén were evacuated. However, some residents did not want to leave the area.
In the meantime it turned out that the particularly gaseous, i.e. H. viscose, rock of the Chaitén, which makes the eruptions so particularly explosive. These were the first scientifically observable rhyolitic eruptions.
A final active phase followed until the beginning of 2010, in which the lava domes grew again. The eruptions receded by 2011, and steam was still escaping until April 2013. The volcano has been inactive again since April 2013.
In May 2015 seismic activities were measured again.
Web links
- Chaitén in the Global Volcanism Program of the Smithsonian Institution (English)
- Chilean volcano monitoring Sernagomin to Chaitén, with webcam link (Spanish)
Individual evidence
- ↑ Chaitén Eruptions in the Global Volcanism Program of the Smithsonian Institution (English)
- ↑ a b c Chaitén Bulletin in the Global Volcanism Program of the Smithsonian Institution (English)
- ↑ One dead as Chilean volcano spews ash for third day. May 4, 2008, accessed July 4, 2015 .
- ^ J. Castro, et al: Rapid ascent of rhyolitic magma at Chaitén volcano, Chile. (2009) (PDF; 683 kB)