Report on Manam (Papua New Guinea) — 15 May-21 May 2002
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 15 May-21 May 2002
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2002. Report on Manam (Papua New Guinea). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 15 May-21 May 2002. Smithsonian Institution and US Geological Survey.
Papua New Guinea
4.08°S, 145.037°E; summit elev. 1807 m
All times are local (unless otherwise noted)
A moderate-sized Strombolian eruption occurred at Manam on 20 May. A pilot reported observing an ash plume at a maximum height of ~9 km on the 20th at 0500. At 0945 on the same day an eruption cloud was visible on satellite imagery extending to the SW. The Rabaul Volcano Observatory reported that a continuous eruption was occurring until at least 0947 on 20 May.
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.