Report on Manam (Papua New Guinea) — November 1993
Bulletin of the Global Volcanism Network, vol. 18, no. 11 (November 1993)
Managing Editor: Richard Wunderman.
Manam (Papua New Guinea) Moderate eruptive activity from both craters
Please cite this report as:
Global Volcanism Program, 1993. Report on Manam (Papua New Guinea) (Wunderman, R., ed.). Bulletin of the Global Volcanism Network, 18:11. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199311-251020.
Papua New Guinea
4.08°S, 145.037°E; summit elev. 1807 m
All times are local (unless otherwise noted)
". . . activity from both craters remained at a low to moderate level in November. Emissions from Southern Crater consisted of weak white vapour throughout the month with thin blue vapour on most days during the latter part of the month. Weak red crater glow was observed on 14, 15, 16, 25, and 26 November. Weak roaring noises accompanied the glow on the 16th and 25th. Incandescent lava ejections accompanied by weak detonations rose to ~80 m above the crater rim on 22 November. On the 29th the vapour emissions became continuous and activity intensified into Strombolian explosions reaching heights of 500-800 m above the crater rim. Similar activity was observed on the 30th. Light ashfalls were recorded on the SW side of the volcano. There were no significant changes recorded by the water tube tiltmeter . . . ."
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 C. McKee, RVO.