Active volcanoes in Marie Byrd Land

Two volcanoes in Marie Byrd Land, Mounts Berlin and Takahe, can be considered active, and a third, Mount Waesche, may be as well, although the chronology of activity is less well constrained. The records of explosive activity of these three volcanoes is well represented through deposits on the volcano flanks, tephra layers found in blue ice areas, as well as by the presence of cryptotephra layers found in West and East Antarctic ice cores. Records of effusive volcanism are found on the volcano flanks, but some deposits may be obscured by pervasive glacerization of the edifices. Based on a compilation of tephra depths/ages in ice cores, the activity patterns of Mounts Takahe and Berlin are dramatically different. Mount Takahe has erupted infrequently over the past 100 ka. Mount Berlin, by contrast, has erupted episodically during this time interval, with the number of eruptions being dramatically higher in the time interval between around 32 to 18 ka. Integration of the Mount Berlin tephra record from ice cores and blue ice areas over a 500 ka time span reveals a pattern of geochemical evolution related to small batches of partial melt being progressively removed from a single source underlying Mount Berlin.