Billy Mitchell (volcano)

Billy Mitchell is a pyroclastic shield in the central part of the island of Bougainville, just north-east of the Bagana Volcano in Papua New Guinea. It is a small pyroclastic shield truncated by a 2 km wide caldera filled by a crater lake. It is named after Billy Mitchell, a 20th-century United States Army general who is regarded as the father of the United States Air Force.

The last two major eruptions were in 1580 AD ± 20 years and about 1030 AD. They were among the largest Holocene eruptions in Papua New Guinea. Both were explosive eruptions with a Volcanic Explosivity Index of at least 5. The 1580 AD ± 20 years eruption produced pyroclastic flows and probably formed its caldera. The ignimbrite deposit from that eruption, which had a VEI of 6, extends 22 km from the caldera to the coast, and its volume is around 10 km3.

Caldera lake
Billy Mitchell caldera lake is about 1,013 m above sea level, has total surface area 3 km2, and the maximum depth  approximately 88.3  m. The only fish species  in the lake is  the eel Anguilla megastoma. Billy Mitchell lake drains into the Tekan River.