Report on Bagana (Papua New Guinea) — June 1990
Bulletin of the Global Volcanism Network, vol. 15, no. 6 (June 1990)
Managing Editor: Lindsay McClelland.
Bagana (Papua New Guinea) Thick ash-laden emission; avalanches from block lava flows
Please cite this report as:
Global Volcanism Program, 1990. Report on Bagana (Papua New Guinea). In: McClelland, L (ed.), Bulletin of the Global Volcanism Network, 15:6. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199006-255020.
Papua New Guinea
6.137°S, 155.196°E; summit elev. 1855 m
All times are local (unless otherwise noted)
"Activity was at a fairly high level throughout June. On most days, thick white clouds were emitted from the summit area and rumbling noises were heard. One to three explosions [per day] occurred on 14, 16, 22, and 24 June, producing thick ash-laden columns to 6 km above the summit. A red glow was observed on all nights when the summit was clearly visible.
"The blocky lava flow being slowly extruded from the summit crater was seen on occasion to overflow onto the upper E, SE, and SW flanks, and rockfalls or debris avalanches (some glowing) were reported daily on the E and SE sides of the volcano."
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.
Information Contacts: P. de Saint-Ours and C. McKee, RVO.