Photograph by Rick Moscati, 1990. The Antarctica plate is mostly asesmic and moves little relative to other plates. Antarctic volcanoes are located along the margins of large rift systems . Erebus is an active volcano with a convecting lava lake within a summit crater. It has been continuously active since 1972.
Most eruptions are small and Strombolian in character, tossing bombs onto the crater rim.
The volcano is less than one million years old. Photograph by Rick Moscati, 1990. The lava within the lava lake is alkalic in composition. Specifically, it is called anorthoclase phonolite. Anorthoclase is a feldspar mineral.