- VolcanoBilly Mitchell volcano is a small shield volcano, which is composed mainly of loose deposits from explosive eruptions (pyroclastic shield). The volcano is located immediately NE of Bagana volcano in central Bougainville Island. Billy Mitchell's typical eruption style are explosive eruptions from the central vent, and the volcano is remarkable for having produced some of the largest explosive eruptions in Papua New Guinea in the past 10,000 years.
Volcano type pyroclastic shield normal or dormant Location Papua-Neuguinea Summit elevation 1544 m / 5,066 ft Billy Mitchell volcano eruptions 1580 ± 20 years Plinian euption, 1030 ± 25 years Plinian eruption Typical eruption style explosiveThe andesitic-dacitic Billy Mitchell volcano has a shallow, but steep-walled and 2.4 km wide caldera filled with an up to 90 m deep crater lake. A small lava dome forms an island near its southern shore. The lake drains through a gap in the northern caldera rim into the Tekan River.
Outside, Billy Mitchell volcano has a smooth eastern flank, which extend as far as 22 km on the eastern side. The other sides are rough and more eroded.
2 major explosive eruptions are known from the volcano, one about 900 years ago and the other about 370 years ago. They produced wide-spread dacitic pyroclastic-fall deposits that cover most of the northern half of Bougainville Island. The younger eruption could have produced the present-day summit caldera. Pyroclastic-flow and -surge deposits from Billy Mitchell extend 25 km to the eastern coast of Bougainville Island.