Report on Manam (Papua New Guinea) — January 1983
Scientific Event Alert Network Bulletin, vol. 8, no. 1 (January 1983)
Managing Editor: Lindsay McClelland.
Manam (Papua New Guinea) Little volcanic activity; steady, moderate seismicity
Please cite this report as:
Global Volcanism Program, 1983. Report on Manam (Papua New Guinea). In: McClelland, L (ed.), Scientific Event Alert Network Bulletin, 8:1. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198301-251020.
Papua New Guinea
4.08°S, 145.037°E; summit elev. 1807 m
All times are local (unless otherwise noted)
"Manam Volcano was essentially quiet during January. Moderately thick white vapour was released from Main crater, and a white-grey plume from the Southern crater. Hardly any noise was heard. Only very light ashfalls were reported from downwind coastal areas of the island. Seismic activity remained steady, with about 2,000 moderate-amplitude events recorded per day. Tilt curves at both stations remained flat."
Geologic Background. The 10-km-wide island of Manam, lying 13 km off the northern coast of mainland Papua New Guinea, is one of the country's most active volcanoes. Four large radial valleys extend from the unvegetated summit of the conical 1807-m-high basaltic-andesitic stratovolcano to its lower flanks. These "avalanche valleys" channel lava flows and pyroclastic avalanches that have sometimes reached the coast. Five small satellitic centers are located near the island's shoreline on the northern, southern, and western sides. Two summit craters are present; both are active, although most historical eruptions have originated from the southern crater, concentrating eruptive products during much of the past century into the SE valley. Frequent historical eruptions, typically of mild-to-moderate scale, have been recorded since 1616. Occasional larger eruptions have produced pyroclastic flows and lava flows that reached flat-lying coastal areas and entered the sea, sometimes impacting populated areas.
Information Contacts: P. de Saint Ours and B. Talai, RVO.