RVO reported that during 29 April-16 May activity at Manam was low, characterized by white, and sometimes blue, vapor plumes rising from Southern Crater. White vapor plumes also rose from Main Crater. Seismicity fluctuated but remained high until 1 May; seismicity then declined to a low on 4 May where it stayed for the rest of the period. RVO reminded people to stay away from the four main radial valleys, and especially the SE and SW ones where most products from the activity at Southern Crater were channeled.

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)