Savo Island

The 6 x 7 km island of Savo, off the NE coast of Guadalcanal Island, consists of a forested andesitic-to-dacitic stratovolcano with a shallow, elliptical 1 x 1.5 km summit crater. Young lava domes are located on the crater floor and the NE rim, and older domes occur on the flanks. Pyroclastic flows and mudflows traveled down valleys from the summit crater to form debris fans along the coast. Thermal areas located in the summit crater, the S to SE flanks, and offshore include areas of steaming ground, fumaroles, small geysers, and hot springs. Spanish explorers observed the first recorded eruption in 1568. Pyroclastic flows during the climactic phase killed almost all inhabitants of the island, and oral traditions also note the expansion of the island on the northern side. Other eruptive episodes occurred during the mid-17th century and during the 1830s to 1840s.