Report on Manam (Papua New Guinea) — February 1988
Scientific Event Alert Network Bulletin, vol. 13, no. 2 (February 1988)
Managing Editor: Lindsay McClelland.
Manam (Papua New Guinea) Vapor emission and glow
Please cite this report as:
Global Volcanism Program, 1988. Report on Manam (Papua New Guinea). In: McClelland, L. (ed.), Scientific Event Alert Network Bulletin, 13:2. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198802-251020.
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 February. Weak to moderate white vapors were observed from both Southern and Main Craters throughout the month. Deep roaring sounds from the summit area (probably Southern Crater) were heard on most days. Blue vapors were released from Southern Crater on 13-14 February, and a dull, fluctuating glow was seen over Main Crater on the 14th. Amplitudes of low-frequency earthquakes continued at the same steady level as in the past 3 months. No significant tilt changes were observed.
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 C. McKee, RVO.