Report on Bagana (Papua New Guinea) — February 1985
Scientific Event Alert Network Bulletin, vol. 10, no. 2 (February 1985)
Managing Editor: Lindsay McClelland.
Bagana (Papua New Guinea) Rockfalls from flank lava flow; strong vapor emission
Please cite this report as:
Global Volcanism Program, 1985. Report on Bagana (Papua New Guinea). In: McClelland, L (ed.), Scientific Event Alert Network Bulletin, 10:2. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198502-255020.
Papua New Guinea
6.137°S, 155.196°E; summit elev. 1855 m
All times are local (unless otherwise noted)
"Eruptive activity continued at Bagana in February, although summit explosive activity was absent, or sporadic and very weak. Strong vapour emission continued, and the very light ash content in the plume was considered to be an effect of entrainment of dust from occasional avalanches on the sides of the summit lava dome. Frequent rockfalls from the edges of the active lava flow on the [N and] NW flanks of Bagana continued."
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.