Report on Manam (Papua New Guinea) — May 1978
Scientific Event Alert Network Bulletin, vol. 3, no. 5 (May 1978)
Managing Editor: David Squires.
Manam (Papua New Guinea) Weak ash emission of last year ended
Please cite this report as:
Global Volcanism Program, 1978. Report on Manam (Papua New Guinea). In: Squires, D. (ed.), Scientific Event Alert Network Bulletin, 3:5. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN197805-251020.
Papua New Guinea
4.08°S, 145.037°E; summit elev. 1807 m
All times are local (unless otherwise noted)
A long phase of relatively weak ash ejection from Southern crater in 1977 ended in mid-January 1978. Similar activity briefly resumed at the end of February and for a few days in mid-March. Emission of moderate amounts of white vapor from Main and Southern craters has occurred since then.
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: R. Cooke, RVO.