Aug 2, 2014

Kilauea – the world’s most active volcanic crater

Kilauea is located on central Hawaii Island, Hawaii. It is situated on the southeastern slope of the great volcanic mountain Mauna Loa, at an elevation of 1,247 m (4,090 ft) above sea level, which is more than 3000 m (almost 10,000 ft) below the summit of the mountain. The crater, which forms a great cavity in the side of the mountain, has an area of about 10 sq km (about 4 sq mi); the walls of the crater are from 60 to 210 m (about 200 to 700 ft) high. Except for occasional lava flows across the floor of the crater, volcanic activity in recent times has been restricted to an inner crater called Halemaumau, which measures more than 900 m (about 3000 ft) across and has a depth of about 400 m (about 1300 ft).

Kilauea's eruptive history has been a long and active one; its name means "spewing" or "much spreading" in the Hawaiian language, referring to its frequent outpouring of lava. Lavas younger than 1,000 years cover 90 percent of the volcano; the oldest exposed lavas date back 2,800 and 2,100 years. The first well-documented eruption of Kilauea occurred in 1823, and since that time the volcano has erupted repeatedly. In the 20th century, major flows occurred in 1920 and 1921, 1950, 1955, 1959, 1965, and 1969. Most historical eruptions have occurred at the volcano's summit or its southwestern rift zone, and are prolonged and effusive in character; however, the geological record shows that violent explosive activity predating European contact was extremely common, and should explosive activity start anew the volcano would become much more dangerous to civilians. Kilauea's current eruption dates back to January 3, 1983, and is by far its longest-lived historical period of activity, as well as one of the longest-lived eruptions in the world; as of January 2011, the eruption has produced 3.5 cubic kilometres (0.84 cu mi) of lava and resurfaced 123.2 km2 (48 sq mi) of land.

By June 1989, it had destroyed the visitors center at the national park, and more than 65 houses by 1990. Since 1911 an observatory has been maintained on the brink of the crater. Kilauea is part of the Hawaii Volcanoes National Park. 
(Adapted from Encarta Encyclopedia and Wikipedia Encyclopedia)