Report on Manam (Papua New Guinea) — June 1996
Bulletin of the Global Volcanism Network, vol. 21, no. 6 (June 1996)
Managing Editor: Richard Wunderman.
Manam (Papua New Guinea) Emissions of ash clouds and increase of seismic activity
Please cite this report as:
Global Volcanism Program, 1996. Report on Manam (Papua New Guinea). In: Wunderman, R. (ed.), Bulletin of the Global Volcanism Network, 21:6. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199606-251020.
Papua New Guinea
4.08°S, 145.037°E; summit elev. 1807 m
All times are local (unless otherwise noted)
Low-level activity persisted during June as in the previous months (BGVN 21:04 and 21:05). Both craters gently released white vapor with occasional whitish gray ash clouds from Southern Crater. There were no audible noises or night glow from either crater. Seismicity was low during the first half of June with daily totals of 350-850 small low-frequency earthquakes. Seismicity increased to 1,090-1,700 events per day after 17 June.
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: D. Lolok, and C. McKee, RVO.