Chaitén (volcano)

Chaitén is a volcanic caldera 3 kilometres (2 mi) in diameter, 17 kilometres (11 mi) west of the elongated ice-capped Michinmahuida volcano and 10 kilometres (6 mi) northeast of the town of Chaitén, near the Gulf of Corcovado in southern Chile. The most recent eruptive phase of the volcano erupted on 2008. Originally, radiocarbon dating of older tephra from the volcano suggested that its last previous eruption was in 7420 BC ± 75 years. However, recent studies have found that the volcano is more active than thought. According to the Global Volcanism Program, its last eruption is 1640 ± 18 years.

The caldera rim reaches 1,122 metres (3,681 ft) above sea level. Before the current eruption, it was mostly filled by a rhyolite obsidian lava dome that reached a height of 962 metres (3,156 ft), partly devoid of vegetation. Two small lakes occupied the caldera floor on the west and north sides of the lava dome.

The translucent grey obsidian which had erupted from the volcano was used by pre-Columbian cultures as a raw material for artifacts and has been found as far away as 400 kilometres (250 mi) to the south and north, for example in Chan-Chan.

Chaitén

Chaitén (/tʃaɪˈtɛn/, chahy-TEN) is a Chilean town, commune and former capital of the Palena Province in Los Lagos Region. The town is located north of the mouth of Yelcho River, on the east coast of the Gulf of Corcovado. The town is strategically located close to the northern end of the Carretera Austral where the highway goes inland.

Evacuation

The town was evacuated in May 2008 when the Chaitén volcano erupted for the first time in more than 9,000 years. The eruption, which commenced May 2, became more violent on May 5, throwing up a high plume of ash and sulfurous steam that rose to 19 miles (31 km), from which ashfall drifted across Patagonia, and over the Atlantic Ocean. During 2005 small earthquakes occurred below Chaiten and the nearby Liquiñe-Ofqui Fault Zone.

The town was completely flooded on May 12, 2008 after a lahar caused the banks of the Blanco River to overflow about 200 m on each side. Over the subsequent weeks, the river excavated a new course through Chaitén, completely destroying a significant part of it by July 2008. (At the time of writing, this process is still ongoing; it is unclear how extensive the damage will ultimately be.) Some defensive work has been undertaken by the government, but they ultimately decided to abandon the town, relocating and compensating all residents. The provincial capital was provisionally moved to Futaleufú after the eruption breakout, but the capital shift was later on declared permanent. The future of the town has become a matter of political controversy in Chile.