Report on Bagana (Papua New Guinea) — October 1989
Scientific Event Alert Network Bulletin, vol. 14, no. 10 (October 1989)
Managing Editor: Lindsay McClelland.
Bagana (Papua New Guinea) Frequent rockfalls; weak explosions; glow
Please cite this report as:
Global Volcanism Program, 1989. Report on Bagana (Papua New Guinea). In: McClelland, L. (ed.), Scientific Event Alert Network Bulletin, 14:10. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198910-255020.
Papua New Guinea
6.137°S, 155.196°E; summit elev. 1855 m
All times are local (unless otherwise noted)
"Activity was at a relatively low level during October. The summit steadily released thick white vapour of moderate volume, with occasional grey clouds associated with reported weak explosions. Weak glow was occasionally seen at night over the summit, and rockfalls continued on the flanks. Seismicity was dominated by rockfall events (6-70/day), but occasional B-type events (0-8/day) were also recorded."
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: C. McKee, RVO.