Report on Bagana (Papua New Guinea) — November 1987
Scientific Event Alert Network Bulletin, vol. 12, no. 11 (November 1987)
Managing Editor: Lindsay McClelland.
Bagana (Papua New Guinea) Vapor emission still moderate-strong; weak glow
Please cite this report as:
Global Volcanism Program, 1987. Report on Bagana (Papua New Guinea). In: McClelland, L. (ed.), Scientific Event Alert Network Bulletin, 12:11. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198711-255020.
Papua New Guinea
6.137°S, 155.196°E; summit elev. 1855 m
All times are local (unless otherwise noted)
Bagana continued to emit moderate-strong white vapors during November. Weak glow from the summit was seen on 6, 13, and 14 November. The number of long-duration seismic events (interpreted as rockfalls from the lava flow) showed a slight increase during the first part of the month to about 40/day, but the activity declined to 10/day by the end of the month.
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. Lowenstein, RVO.