Gaussberg (or Schwarzen Berg,[3] Mount Gauss) is an extinct, 370-metre-high (1,210-foot) high volcanic cone in East Antarctica fronting on Davis Sea immediately west of Posadowsky Glacier.

[2] Gaussberg is within the Antarctic territory claimed by Australia,[14] and the only ice-free outcrop between Mirny Station and the Vestfold Hills.

[15] It consists of a 370-metre-high (1,210-foot), 1.5-kilometre-wide (0.93-mile)[1] cone located between the East Antarctic Ice Sheet on three sides and the sea on the fourth.

[32] The volcano has a uniform chemical composition[33] consisting of lamproite (originally identified as leucitite),[34] which defines a potassium-rich mafic rock suite.

[40] The magma may have formed through the incomplete melting of phlogopite-rich mantle and further chemical processes such as crystal fractionation that raised the potassium/aluminium ratio above 1.

[41] Deep mantle structures that formed through subduction billions of years ago and remained isolated since then have been proposed as the source of Gaussberg lamproites.

Early research suggested a Pliocene or Miocene age based on a presumed history of the Antarctic Ice Sheet and comparisons between the appearance of Gaussberg with Kerguelen volcanoes.

[44] Gaussberg was probably constructed in a single eruptive episode[45] but there is evidence that the present-day edifice formed on an older, eroded volcano.

[22] There are different views on how erosion affected Gaussberg; some think that it was largely spared[46] and others that erosion wore down the initially much larger edifice to its current size;[47][9] the latter theory is the preferred view of the Global Volcanism Program[48] and is supported by aeromagnetic data which suggest an initial size of 10 kilometres (6.2 mi).

[11] Dust layers in the Siple Dome ice core may come from wind-driven erosion of Gaussberg rocks.

[50] Emperor penguin rookeries occur at the mountain[55] and snow petrels were observed to breed there,[56] but overall there is not much fauna at Gaussberg.