Report on Bagana (Papua New Guinea) — 20 August-26 August 2014
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 20 August-26 August 2014
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2014. Report on Bagana (Papua New Guinea). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 20 August-26 August 2014. Smithsonian Institution and US Geological Survey.
Papua New Guinea
6.137°S, 155.196°E; summit elev. 1855 m
All times are local (unless otherwise noted)
During 25-26 August the Darwin VAAC reported ash plumes at Bagana that rose 2.1-2.4 km (7,000-8,000 ft) a.s.l. and drifted 65-120 km W and WNW. The Aviation Color Code remained at Orange.
Geologic Background. Bagana volcano, occupying a remote portion of central Bougainville Island, is one of Melanesia's youngest and most active volcanoes. This massive symmetrical cone was largely constructed by an accumulation of viscous andesitic lava flows. The entire edifice could have been constructed in about 300 years at its present rate of lava production. Eruptive activity is frequent and characterized by non-explosive effusion of viscous lava that maintains a small lava dome in the summit crater, although explosive activity occasionally producing pyroclastic flows also occurs. Lava flows form dramatic, freshly preserved tongue-shaped lobes up to 50 m thick with prominent levees that descend the flanks on all sides.