Report on Manam (Papua New Guinea) — 28 August-3 September 2013
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 28 August-3 September 2013
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2013. Report on Manam (Papua New Guinea). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 28 August-3 September 2013. 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)
RVO reported that Manam's Southern Crater was quiet during 16-17 August. Occasional light-gray emissions observed during 18-20, 22-23, and 25 August rose 100 m above the crater and drifted NW. Incandescence from the crater was seen during 18-19 and 21-26 August, and incandescent fragments were ejected during 21-25 August.
A small eruption began at 1830 on 26 August with emissions of dark ash clouds that rose 500-600 m. Bright incandescence from the crater and occasional ejected incandescent fragments were observed. Roaring and rumbling was heard by island residents as well as residents in Bogia, 25-30 km SSW of Manam on the N coast of the mainland. By the next morning the emissions decreased and were light gray to brown.
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.
Source: Rabaul Volcano Observatory (RVO)