Report on Manam (Papua New Guinea) — November 1982
Scientific Event Alert Network Bulletin, vol. 7, no. 11 (November 1982)
Managing Editor: Lindsay McClelland.
Manam (Papua New Guinea) Steady, moderate activity; light ashfalls
Please cite this report as:
Global Volcanism Program, 1982. Report on Manam (Papua New Guinea) (McClelland, L., ed.). Scientific Event Alert Network Bulletin, 7:11. Smithsonian Institution.
Papua New Guinea
4.08°S, 145.037°E; summit elev. 1807 m
All times are local (unless otherwise noted)
"Both craters displayed steady, moderate levels of activity in November. Southern crater was somewhat more active with rumbling sounds commonly accompanying the usually pale grey to brown ash-laden emissions. Main crater emissions were usually white and pale grey, but occasional brown ash-laden emissions were seen. Light ashfalls were reported in coastal parts of Manam on most days in November. No crater incandescence was observed. Seismic activity was steady at normal levels throughout November, and tiltmeter measurements showed no trends."
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, RVO.