Report on Bagana (Papua New Guinea) — March 1986
Scientific Event Alert Network Bulletin, vol. 11, no. 3 (March 1986)
Managing Editor: Lindsay McClelland.
Bagana (Papua New Guinea) Increased lava extrusion continues; B-type event
Please cite this report as:
Global Volcanism Program, 1986. Report on Bagana (Papua New Guinea). In: McClelland, L. (ed.), Scientific Event Alert Network Bulletin, 11:3. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198603-255020.
Papua New Guinea
6.137°S, 155.196°E; summit elev. 1855 m
All times are local (unless otherwise noted)
"The phase of stronger extrusive activity continued into March, and was detected both seismically and visually. There were occasional reports of moderate to strong white to dark brown emissions from the summit, which displayed a weak glow whenever visible at night.
"The seismicity, which increased sharply in mid-February, declined slightly during the first week of March, but rose again steadily to a peak of 145 B-type events/day on the 12th before gradually declining to ~20 events/day at month's end."
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.