Report on Bagana (Papua New Guinea) — 19 July-25 July 2023
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 19 July-25 July 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, 19 July-25 July 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)
According to new articles, more than 7,000 people needed temporary accommodations due to the eruption at Bagana, with about 1,000 of those in evacuation shelters. Ashfall was deposited over a broad area, contaminating water supplies, affecting crops, and collapsing some roofs and houses in rural areas. Schools were temporarily shut down. The Alert Level was lowered to Stage 2 (on a four-level scale).
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.