Report on Bagana (Papua New Guinea) — August 1984
Scientific Event Alert Network Bulletin, vol. 9, no. 8 (August 1984)
Managing Editor: Lindsay McClelland.
Bagana (Papua New Guinea) Lava production continues; SO2-rich plume
Please cite this report as:
Global Volcanism Program, 1984. Report on Bagana (Papua New Guinea). In: McClelland, L. (ed.), Scientific Event Alert Network Bulletin, 9:8. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198408-255020.
Papua New Guinea
6.137°S, 155.196°E; summit elev. 1855 m
All times are local (unless otherwise noted)
"The predominately effusive eruption continued. When last observed (21 July), the viscous blocky lava flow on the NW flank had reached an altitude of 1,000 m and had an estimated volume of 1.3 x 106 m3. A moderate plume of dense, white, SO2-rich gases continued to be emitted from the summit crater. Seismicity from the volcano was at a low level, with only a few B-type and explosion earthquakes per day."
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, RVO.