Report on Bagana (Papua New Guinea) — October 1984
Scientific Event Alert Network Bulletin, vol. 9, no. 10 (October 1984)
Managing Editor: Lindsay McClelland.
Bagana (Papua New Guinea) Lava flow continues; earthquake swarm
Please cite this report as:
Global Volcanism Program, 1984. Report on Bagana (Papua New Guinea). In: McClelland, L. (ed.), Scientific Event Alert Network Bulletin, 9:10. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198410-255020.
Papua New Guinea
6.137°S, 155.196°E; summit elev. 1855 m
All times are local (unless otherwise noted)
"An uncharacteristic swarm of shallow tectonic-like earthquakes together with banded low-amplitude harmonic tremor commenced on 19 October about 2000 and continued through October. During the previous week the NW lava flow collapsed to form a well-defined lava channel below the point where the flow turns sharply W. The toe of the lava flow continued to encroach on a satellite dome at the W foot of Bagana. Numerous solfataras have given a distinctive facia to the ESE summit."
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: K. McCue, Bougainville Island Copper Ltd.