Report on Manam (Papua New Guinea) — November 1988
Scientific Event Alert Network Bulletin, vol. 13, no. 11 (November 1988)
Managing Editor: Lindsay McClelland.
Manam (Papua New Guinea) Ash and vapor emission; weak glow
Please cite this report as:
Global Volcanism Program, 1988. Report on Manam (Papua New Guinea) (McClelland, L., ed.). Scientific Event Alert Network Bulletin, 13:11. Smithsonian Institution.
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 November with weak-moderate white vapour emissions from the two summit craters. Emissions from Southern Crater frequently contained small amounts of grey ash and blue vapour. On the 29th, red glow became sub-continuous and weak incandescent projections were observed. Rumbling noises from the same crater were heard throughout the month. Seismicity remained at a normal inter-eruptive level with a daily average of 1,120 low-frequency events. Tilt measurements indicated 3 µrad of inflation over the month."
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: I. Itikarai and P. Lowenstein, RVO.