Report on Bagana (Papua New Guinea) — May 1986
Scientific Event Alert Network Bulletin, vol. 11, no. 5 (May 1986)
Managing Editor: Lindsay McClelland..
Bagana (Papua New Guinea) Plumes; rockfall events from active lava flow
Please cite this report as:
Global Volcanism Program, 1986. Report on Bagana (Papua New Guinea). In: McClelland, L. (ed.), Scientific Event Alert Network Bulletin, 11:5. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198605-255020.
Papua New Guinea
6.137°S, 155.196°E; summit elev. 1855 m
All times are local (unless otherwise noted)
"Stronger activity continued through May. Moderate to strong white to brown emissions were reported daily. Weak glow from the summit was visible on five nights. There were 40-70 low-frequency seismic events/day, about the same as during the last half of April. Most of these events are probably due to rockfalls from the margins of the active lava flow."
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.