Report on Bagana (Papua New Guinea) — June 1989
Scientific Event Alert Network Bulletin, vol. 14, no. 6 (June 1989)
Managing Editor: Lindsay McClelland.
Bagana (Papua New Guinea) Explosions; S-flank lava flow remains active
Please cite this report as:
Global Volcanism Program, 1989. Report on Bagana (Papua New Guinea). In: McClelland, L. (ed.), Scientific Event Alert Network Bulletin, 14:6. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198906-255020.
Papua New Guinea
6.137°S, 155.196°E; summit elev. 1855 m
All times are local (unless otherwise noted)
"Bagana is currently the most active volcano in Papua New Guinea. Unfortunately, civil disturbance on Bougainville Island Island prevents proper monitoring. The observer reported fluctuating night glows from the summit and from the new (blocky) lava flow on the S flank. Incandescent rockfalls were frequent on all flanks, accompanied by rumbling sounds. Explosions and incandescent projections over the crater were reported 10 and 12-15 June. The thick, white to brown plume . . . produced occasional light ashfalls downwind."
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 B. Talai, RVO.