Report on Manam (Papua New Guinea) — 6 November-12 November 2019
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 6 November-12 November 2019
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2019. Report on Manam (Papua New Guinea) (Sennert, S, ed.). Weekly Volcanic Activity Report, 6 November-12 November 2019. 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 at 1330 on 2 November a single large explosion at Manam generated a dense dark ash plume that rose 1 km above the summit and drifted NW. A shock wave was felt at the Bogia Government station (about 40 km SE) about 1 minute later. RSAM values on 6 November fluctuated between 250 and 360 units but began to increase around 1430 and triggered alerts around 1445. Values continued to increase and reached 400-500 units, heralding an eruption which began during 1600-1630. A gray ash plume rose 1 km and drifted NW. Incandescent material ejecting from the vent was visible at the start of the eruption and became more visible as the evening grew darker. The eruption peaked in intensity around 1930, then declined and ceased during 2100-2200.
Geological Summary. 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 basaltic-andesitic stratovolcano to its lower flanks. These 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 observed eruptions have originated from the southern crater, concentrating eruptive products during much of the past century into the SE valley. Frequent 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)