Major Volcanoes of the World

Mauna Loa

Mauna Loa is an active shield volcano in the Hawaiian Islands, one of five volcanoes that form the Island of Hawai?i. The Hawaiian name "Mauna Loa" means "Long Mouns". Mauna Loa is Earth's largest volcano, with a volume estimated at approximately 18,000 cubic miles (75,000 km³), although its peak is about 36 m (120 ft) lower than that of its neighbour, Mauna Kea. Lava eruptions from Mauna Loa are very fluid and the volcano has extremely shallow slopes as a result.
The volcano has probably been erupting for at least 700,000 years and may have emerged from the sea about 400,000 years ago, although the oldest known dated rocks do not extend beyond 200,000 years.Its magma comes from a hotspot in the Earth's mantle far beneath the island that has been responsible for the creation of the Hawaiian island chain for tens of million of years. The slow drift of the Pacific Plate will eventually carry the volcano away from the hotspot, and the volcano will thus become extinct within 500,000 to one million years from now.
The first recorded summiting of Mauna Loa was in 1794 by naturalist Archibald Menzies, then-Lieutenant Joseph Baker, and two others. Using a barometer, they calculated its height within 50 feet.
Mauna Loa's most recent eruption occurred from March 24, 1984 to April 15, 1984. No recent eruptions of the volcano have caused fatalities, but eruptions in 1926 and 1950 destroyed villages, and the city of Hilo is partly built on lava flows from the late 19th century. In view of the hazards it poses to population centers, Mauna Loa is part of the Decade Volcanoes program, which encourages studies of the most dangerous volcanoes. Mauna Loa has been intensively monitored by the Hawaiian Volcano Observatory (HVO) since 1912. Observations of the atmosphere are undertaken at the Mauna Loa Observatory, and of the Sun at the Mauna Loa Solar Observatory, both located near its summit. Hawaii Volcanoes National Park covers the summit and the southeastern flank of the volcano, including a separate volcano, Kilauea.

Hazards
Volcanic eruptions in Hawai?i rarely cause fatalities—the only fatality due to volcanic activity there in the last century occurred at Kilauea in 1924, when an unusually explosive eruption hurled rocks at onlookers, killing one. However, property damage is common. Mauna Loa is a Decade Volcano, which means it has been identified as worthy of particular research in light of its frequent eruptions and proximity to populated areas. Many towns and villages near the volcano are built on lava which has erupted in the last two hundred years and there is a very strong likelihood that future eruptions will cause damage to populated areas.