RVO reported that Manam's Main Crater emitted gray ash plumes during 11-19 March. The plumes rose to altitudes of 2.3 km (7,500 ft) a.s.l. and drifted SE. Incandescence was visible the evenings of 11, 12, 16, and 18 March. Vapor clouds and occasional diffuse ash clouds were emitted from South Crater during 11-20 March.

According to a news article, four people were killed and one injured from an "ash-and-mud" avalanche in a valley on the northern part of the island. RVO received the report on 15 March, but had not yet confirmed whether it was a mudflow.

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.

Sources: Rabaul Volcano Observatory (RVO), Reuters