Mount Waesche is a mountain of volcanic origin at the southern end of the Executive Committee Range in Marie Byrd Land, Antarctica.
It is 3,292 metres (10,801 feet) high, and stands 20 kilometres (12 miles) southwest of Mount Sidley, the highest volcano in Antarctica.
The mountain lies southwest of the Chang Peak caldera and is largely covered with snow and glaciers, but there are rock exposures on the southern and southwestern slopes.
The volcano may have been active as late as the Holocene, with tephra layers recovered from ice cores possibly originating from Mount Waesche.
Mount Waesche is the more conspicuous peak and lava flows crop out on its southern[7] and southwestern flank,[12] while a 2 kilometres (1.2 mi) wide caldera lies at its summit.
[12] A 0.5 metres (1 ft 8 in) long[7] large radial dyke projects from Mount Waesche[15] and is the only part of the edifice where hyaloclastic tuff crops out.
[10] Two sets of moraines formed by volcanic debris – one containing ice, the other without – lie on the southern and southwestern flank, reaching heights of 120 metres (390 ft) and lengths of about 3 kilometres (1.9 mi).
[31] Chang Peak and Mount Waesche appear to be located outside of the Executive Committee Range volcanic lineament.
[11] Phenocrysts at Chang Peak include aenigmatite, alkali feldspar, ilmenite and quartz and at Mount Waesche olivine, plagioclase and titanaugite.
[34] Unusually for volcanoes in Marie Byrd Land, the chemistry of volcanic rocks at Mount Waesche appears to have changed over time.
[42] A layer of volcanic ash, about 8,000 years old, that was identified in the region through radar data probably originated at Mount Waesche.