Erebus hotspot
The Erebus hotspot is a volcanic hotspot responsible for the high volcanic activity on Ross Island in the western Ross Sea of Antarctica. Its current eruptive zone, Mount Erebus, has erupted continuously since its discovery in 1841.[1]
Magmas erupted from the Erebus hotspot are similar to those erupted from hotspots at the active East African Rift in eastern Africa.[1] Mount Bird at the northernmost end of Ross Island and Mount Terror at its eastern end are large basaltic shield volcanoes that have been potassium-argon dated to be 3.8β4.8 and 0.8β1.8 million years old.[1]
The Erebus hotspot has been interpreted to be the cause of spreading at the Terror Rift.[1] Its mantle plume, estimated to be 250 to 300 km (160 to 190 mi) in diameter, extends 200 km (120 mi) below the surface where it changes into a narrow column that further extends 400 km (250 mi) below the surface.[2]