Report on Manam (Papua New Guinea) — February 1998
Bulletin of the Global Volcanism Network, vol. 23, no. 2 (February 1998)
Managing Editor: Richard Wunderman.
Manam (Papua New Guinea) Low-level vapor emission and nighttime summit-crater glow in February
Please cite this report as:
Global Volcanism Program, 1998. Report on Manam (Papua New Guinea). In: Wunderman, R. (ed.), Bulletin of the Global Volcanism Network, 23:2. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199802-251020.
Papua New Guinea
4.08°S, 145.037°E; summit elev. 1807 m
All times are local (unless otherwise noted)
Activity at both summit craters of Manam was low throughout February. Both craters emitted continuous weak white vapor. Glow was observed at Southern crater on the nights of 3, 5-9, 14-18, and 25-27 February, but there were no sounds.
Seismic activity showed no significant change: 1,100-1,300 low-frequency earthquakes of very low magnitude were recorded daily. Following a deflation of ~1.5 µrad in January, radial tilt as measured at Tabele stabilized for February.
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: Ben Talai, RVO.