Chaiten ongoing activity

Based on web camera views and analyses of satellite imagery, the Buenos Aires VAAC reported that on 14 October an ash plume from Chaitén's lava-dome complex rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 150 km NNE. A diffuse plume was seen the next day drifting 15 km SW at the same altitude as the previous day. During 15-16 October, a thermal anomaly was seen. On 18 October, a possible plume drifted 50 km SE at an altitude of 2.1 km (7,000 ft) a.s.l. Diffuse ash plumes possibly mixed with steam and gas rose to an altitude of 1.8 km (6,000 ft) a.s.l. on 20 October and drifted NE and SE.

Geologic Summary
Chaitén is a small, glacier-free caldera with a Holocene lava dome located 10 km NE of the town of Chaitén on the Gulf of Corcovado. A pyroclastic-surge and pumice deposit considered to originate from the eruption that formed the elliptical 2.5 x 4 km wide summit caldera was dated at about 9400 years ago. A rhyolitic, 962-m-high obsidian lava dome occupies much of the caldera floor. Obsidian cobbles from this dome found in the Blanco River are the source of prehistorical artifacts from archaeological sites along the Pacific coast as far as 400 km away from the volcano to the north and south. The caldera is breached on the SW side by a river that drains to the bay of Chaitén, and the high point on its southern rim reaches 1122 m.
Video http://www.youtube.com/watch?v=Q9lbAS_bPSU
Map
Source: Buenos Aires Volcanic Ash Advisory Center (VAAC)
Chaitén Information from the Global Volcanism Program

Si è osservato una colonna di cenere vulcanica alta 2,1 km il 14 ottobre scorso sopra il Chaiten in Cile (dati VAAC di Buenos Aires) per poi essere spinta in diverse direzioni fine al 20 ottobre quando si elevava ancora all'altezza di 1,8 km in direzione NE e SE.

Il Chaiten consiste in un edificio vulcanico che culmina a 1122m slm con la sua caldera formatasi 9400 anni fa all'interno della quale vi è un domo lavico riolitico di cui l'ossidiana era sfruttata dall'uomo per le sue qualità sin dalla preistoria.

Quando il Chaiten ha di nuovo eruttato nel 2008, il 2 maggio, è tornato ad essere un vulcano attivo dopo circa 9000 anni di riposo, provocando ingenti danni materiali nell'omonima cittadina vicina in mettendo a rischio la popolazione che ha dovuto evacuare la cittadina diverse volte.

Volcán San José on the far left horizon rises to the north above ice pinnacles at the Nieves Negras pass on the Chile/Argentina border.
The summit (5856 m) of San José is formed by a cluster of six Holocene craters, pyroclastic cones, and blocky lava flows that lie within a series of elongated, 0.5 x 2 km wide nested craters.

Mild phreatomagmatic eruptions were recorded at San José in the 19th and 20th centuries.

Its last eruption was in 1960.
Photo courtesy of Oscar González-Ferrán (University of Chile)
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Il vulcano San José, situato alla frontiera tra Cile e Argentina, possiede una sommità formata da 6 crateri dell'Olocene, da coni piroclastici e da colate di lava solidificata. Il rilievo culmina a 5856 m.

Le ultime eruzioni freatomagmatiche risalgono all'800 e 900.

La sua ultima risale al 1960.

Le volcan San José, situé à la frontière entre le Chilie et l'Argentine, possède un sommet formé par 6 cratères appartenant à l'holocène, des cones pyroclastiques et des coulées de lave solidifiée. Le relief culmine à 5856 m.

Ses dernières éruptions phréatomagmatiques remontent aux XIXe et XX.

Sa dernière éruption a eu lieu en 1960.

Llaima volcano eruption intensifies!

SANTIAGO, April 5 2009(Reuters)

Officials fear mud avalanches as lava melts snow.

71 people evacuated

Chile's Llaima volcano, one of South America's most active, belched ash 4 miles (7 km) into the sky that was blown towards neighboring Argentina in an intensifying eruption that prompted more evacuations.

Llaima, which is in Chile's picturesque lake region about 435 miles (700 km) south of the capital Santiago, began spitting lava in a fresh bout of activity on Friday night.

It erupted fiercely on Jan. 1, 2008, and has expelled rock and ash sporadically since then.

State National Emergency Office ONEMI said a towering cloud of ash was being blown towards Argentina, extending 62 miles (100 km) southeast of the volcano.

"The volcano continues to permanently erupt with explosions, lava flows and ash," Helia Vargas, an official with the state National Emergency Office, told Reuters.

"More people were evacuated overnight because of the risk of mud avalanches as the lava melts snow on the volcano," she said.

Lava was flowing down the volcano's sides in three directions for hundreds of meters (yards), Vargas said.

ONEMI said 71 people have been evacuated from the vicinity of volcano, which is surrounded by small towns and villages as well as the Conguillio national park.Rains overnight and ash have swollen a river near the volcano and swept away a pedestrian bridge, but there were no immediate reports of other damage.

Chile's chain of about 2,000 volcanoes is the world's second-largest after Indonesia.

Some 50 to 60 are on record as having erupted, and 500 are potentially active.

The 10,253-foot (3,127-metre) Llaima was the second to erupt in the past year.

The Chaiten volcano, 760 miles (1,200 km) south of Santiago in the Patagonia region, erupted last May for the first time in thousands of years, spewing ash, gas and molten rock and prompting the evacuation of thousands of people.

Ash from Chaiten soared 20 miles (32 km) into the sky, swelled rivers and caused floods that damaged dozens of houses and destroyed much of the nearby town of the same name.

The ash cloud from Chaiten coated towns in Argentina, and was visible from space.

Chaiten erupted again in February, leading to the evacuation of residents who had rejected a government plan to abandon the town and rebuild it a few miles (km) away.

(Reporting by Simon Gardner and Antonio de la Jara)

Llaima, Cile, 700 km a sud di Santiago, la capitale.

La catena del Cile, composta da cica 2000 vulcani, è la seconda in ordine di grandezza dopo quella dell'Indonesia.

Il vulcano Llaima intensifica la sua attività sparando grandi colonne di cenere vulcanica (fino a 7 km di altezza) e facendo notevoli colate di lava che a contatto della neve, fonde e potrebbe creare delle valanghe di fango pricolose.

71 persone evacuate.

Appartenente alla stessa catena, il vulcano Chaiten invece è situato a 1200 km da Santiago in Patagonia. Ha eruttato dopo milleni di inattività a maggio scorso creando danni ingenti al territorio locale.

Volcan Llaima, Chilie, 700 km de Santiago, la capitale.

La chaine du Chilie, composée d'environ 2000 volcans, est la seconde plus importante après celle de l'Indonésie.

Le volcan intensifie son activité projetant dans le ciel des colonnes de cendres de près de 7 km e en émettant des coulées de lave qui mélangées aux neiges fondantes risquent de créer de dangereuses avalanches de boues.

71 personnes évacuées.

De la meme chaine, le volcan Chaiten en revanche, situé lui à 1200 km de Santiago en Patagonie, est entré en éruption en mai dernier après une veille de plusieurs miliers d'années, causant de grandes destruction dans le territoire local.