Report on Manam (Papua New Guinea) — January 1989
Scientific Event Alert Network Bulletin, vol. 14, no. 1 (January 1989)
Managing Editor: Lindsay McClelland.
Manam (Papua New Guinea) Weak ash emission and glow
Please cite this report as:
Global Volcanism Program, 1989. Report on Manam (Papua New Guinea). In: McClelland, L (ed.), Scientific Event Alert Network Bulletin, 14:1. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198901-251020.
Papua New Guinea
4.08°S, 145.037°E; summit elev. 1807 m
All times are local (unless otherwise noted)
"Activity continued at a low level during January with weak to moderate emissions of white vapour. Emissions from Southern Crater were accompanied by small amounts of grey ash on the 9th, 23rd, and 24th, and blue vapour on the 18th, 19th and 24th. Deep rumbling noises from this crater were often heard and weak fluctuating glow was observed on the 8th, 30th, and 31st. Seismicity remained at a low-moderate level with 700-1,200 small B-type volcanic events recorded daily. No significant tilt change was recorded."
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: C. McKee, H. Patia, and P. de Saint-Ours, RVO.