Chaitén (volcano) facts for kids
Quick facts for kids Chaitén |
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2003 photograph from the International Space Station.
The caldera is the circular feature visible in the lower part of the image. The town of Chaitén is to the top. (This image is aligned roughly southwest, around 220°.) |
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| Highest point | |
| Elevation | 1,122 m (3,681 ft) |
| Geography | |
 Chaitén
Location in Chile
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| Location | 10 kilometres (6 mi) northeast of Chaitén, Palena Province, Los Lagos Region, Chile |
| Parent range | Andes |
| Geology | |
| Mountain type | Caldera |
| Volcanic belt | South Volcanic Zone |
| Last eruption | 2008 to 2011 |
Chaitén is a volcano located in southern Chile. It is a type of volcano called a caldera, which is a large, bowl-shaped hollow. This caldera is about 3 kilometers (2 miles) wide. It sits about 10 kilometers (6 miles) northeast of the town of Chaitén, close to the Gulf of Corcovado.
The most recent eruptions of Chaitén happened between 2008 and 2011. Before this, scientists believed its last eruption was around 7420 BC. However, new studies show the volcano has been more active than first thought.
The rim of the caldera reaches 1,122 meters (3,681 feet) above sea level. Before the 2008 eruption, the caldera was mostly filled by a dome of hardened lava. This lava was a type of rock called rhyolite obsidian. It reached a height of 962 meters (3,156 feet) and had little plant life. Two small lakes were found on the caldera floor, on the west and north sides of the lava dome.
The clear, gray obsidian from the volcano was very important. People living in the area before Christopher Columbus used it. They made tools and other items from this rock. Pieces of Chaitén obsidian have been found far away, up to 400 kilometers (250 miles) to the south and north.
Contents
Chaitén Volcano: The 2008 Eruption
The Chaitén volcano began a new period of eruptions on May 2, 2008. This was its first major eruption since about 1640.
Evacuation and Ash Cloud
The Chilean government quickly started to move people out of the nearby town of Chaitén. About 4,200 people lived there. Most residents were safely evacuated by May 3, 2008. Sadly, one elderly person died while traveling by sea to Puerto Montt.
By the afternoon of May 3, a huge cloud of volcanic ash had spread. It traveled across Chile and Argentina all the way to the Atlantic Ocean. This ash contaminated water supplies. The town of Futaleufú, about 75 kilometers (47 miles) southeast, was covered in ash. Initial reports said it was 30 centimeters (12 inches) deep. Later studies found the average ash depth was closer to 5 to 10 centimeters (2 to 4 inches).
Eruption Intensifies
On May 6, 2008, the eruption became much stronger. It produced fast-moving currents of hot gas and rock called pyroclastic flows. The eruption column, which is the plume of ash and gas, rose very high. It reached an estimated 30,000 meters (98,000 feet) into the sky. Because of this, almost everyone remaining in Chaitén and nearby villages, including Futaleufú, was evacuated.
At the start of the eruption, two separate openings, or vents, formed in the old lava dome. By May 6, these had joined into one large vent about 800 meters (2,600 feet) wide. Experts warned that more large pyroclastic events were possible. They also said the eruption could continue for a long time.
New Lava Dome Forms
Throughout May and June 2008, the volcano continued to erupt ash. The amount of ash varied but slowly decreased. There were also occasional earthquakes and pyroclastic flows. On May 21, scientists saw a new lava dome forming inside the crater. By May 24, this new dome was taller than the old one.
The new dome first grew towards the north. But then, new vents opened in the south of the old dome around June 11. This caused the dome to expand towards the south. Eventually, it blocked the water drainage from the caldera floor.
By July 3, 2008, Chaitén was still erupting. It had an ash column up to 3,000 meters (9,800 feet) high. The lava dome continued to grow. Scientists were unsure if the dome would remain stable. There was a risk it could collapse, causing more explosive pyroclastic eruptions.
In August 2008, an expedition reached the top of the volcano. They found the lava dome was 120 meters (390 feet) high. Earthquakes were felt at the summit. The dome was loudly releasing gas, and hot rocks were falling from its sides to the crater floor.
On February 19, 2009, part of the lava dome collapsed. This sent pyroclastic flows down the Chaitén river valley. They reached about 5 kilometers (3 miles) from the town of Chaitén. Ash once again fell on Futaleufú and parts of Chubut province in Argentina. The approximately 160 people in Chaitén were strongly urged to leave. Most of them were evacuated that day.
Impact and Recovery
The Chaitén eruption caused significant damage to the surrounding areas.
Environmental Effects
Forests near the volcano were burned by the hot pyroclastic flows and explosions. Large areas of southern Argentina and Chile were covered in ash. This had possible long-term effects on farming. However, volcanic ash can also add new minerals to the soil, which can be good for agriculture over time.
Large amounts of ash fell in some places. This created a risk of lahars, which are dangerous mudflows made of volcanic ash and water. Lahars can be very destructive.
Damage to Chaitén Town
Starting on May 12, lahars caused severe flooding in the town of Chaitén. Ash mud covered many buildings, sometimes more than a meter (3 feet) deep. The original path of the Chaitén River through the town was completely filled with mud. Over the next few weeks, the river carved a new path. This new path went right through the town, destroying a large part of it by July 2008.
The government has done some work to protect the town. There were plans to move the town about 10 kilometers (6 miles) north, but these plans have not been completed. The town of Chaitén is slowly recovering. Its current population is about 900 people.
A Rare Eruption
The 2008 Chaitén eruption was very important because it was the first major explosive eruption of rhyolite magma in almost a century. The last one of this size was the 1912 eruption of Novarupta in Alaska.
While there have been other rhyolitic eruptions in this part of Chile in the past, they are quite rare. No other historical rhyolitic eruption in the region has been as large as Chaitén's.
See also
In Spanish: Volcán Chaitén para niños
