Wikipedia:Today's featured article/June 22, 2011

Cerro Azul is an active stratovolcano in the Maule Region of central Chile, immediately south of Descabezado Grande. Part of the South Volcanic Zone of the Andes, it rises 3,788 meters (12,428 ft) and is capped by a summit crater 500 meters (1,600 ft) wide that opens to the north. Cerro Azul is responsible for South America's largest recorded eruptions, in 1846 and 1932. In 1846, an effusive eruption formed the vent at the site of present-day Quizapu Crater on the northern flank of Cerro Azul and sent lava flowing down the sides of the volcano, creating a lava field of 8–9 square kilometers (3–3.5 square miles). In 1932, one of the largest explosive eruptions of the 20th century occurred at Quizapu Crater and sent 9.5 cubic kilometers (2.3 cu mi) of ash into the atmosphere. The volcano's most recent eruption was in 1967. The South Volcanic Zone has a long history of eruptions and poses a threat to the surrounding region. Any volcanic hazard—ranging from minor ashfalls to pyroclastic flows—could pose a significant risk to humans and wildlife. Despite its current inactivity, Cerro Azul could produce another major eruption. (more...)

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