Bagana

Bagana volcano, on Papua New Guinea's Bougainville Island, is characterized by the extrusion of thick, viscous andesitic lava flows. This dramatic photo shows a massive lava flow, bound by prominent lateral levees, descending from the summit and ponding against ruggedly dissected forested hills at the base of the volcano. Bagana is constructed almost entirely of overlapping lava-flow lobes. Slow lava extrusion, occasionally accompanied by explosive activity, has been continuing since 1972.