Report on Bagana (Papua New Guinea) — 2 August-8 August 2023
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 2 August-8 August 2023
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2023. Report on Bagana (Papua New Guinea) (Sennert, S, ed.). Weekly Volcanic Activity Report, 2 August-8 August 2023. Smithsonian Institution and US Geological Survey.
Papua New Guinea
6.137°S, 155.196°E; summit elev. 1855 m
All times are local (unless otherwise noted)
The Darwin VAAC reported that an intense thermal anomaly over Bagana was identified in satellite images during 30-31 July. Ash emissions rose to 2.4 km (8,000 ft) a.s.l. and drifted WSW on 30 July. The VAAC received a ground report from RVO describing localized emissions at 0900 on 31 July. Ash was not identified in satellite images, though weather clouds obscured views.
Geological Summary. Bagana volcano, in a remote portion of central Bougainville Island, is frequently active. 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 characterized by non-explosive effusion of viscous lava that maintains a small lava dome in the summit crater, although occasional explosive activity produces pyroclastic flows. Lava flows with tongue-shaped lobes up to 50 m thick and prominent levees descend the flanks on all sides.