Santa Maria Island is the top of Gaua, a stratovolcano. Gaua rises about 9,800 feet (3,000 m) from the sea floor. Steaming Hill Lake, a crescent-shaped crater lake, is just below Mt. Gharat, a secondary cone and summit of the volcano. Solfataras are on the south side of the volcano and hot springs are on the north slope. Map from Fisher (1957) after J.R. Baker. Gaua has had at least 13 eruptions from Mt. Gharat since 1963. The most recent eruption was in 1982 and lasted less than one day. Most of the historic eruptions have lasted only 1-2 days with the 1963 and 1973-1974 eruptions lasting a few months. Each of these eruptions was small with VEI of about 2 except for the 1965 eruption which had VEI=3.
Additional Sources of Information:
Department of Geology, Mines and Water Resources, Vanuatu.
ORSTOM assists with the monitoring of the active volcanoes in Vanuatu.
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