The Gamburtsev mountains and the origin and early evolution of the Antarctic Ice Sheet

The nature of initial glaciation on Antarctica about 34 million years ago is a mystery. Results from an intensive radar survey now show that the Gamburtsev mountains at Dome A, at the centre of the present ice sheet, were initially incised by rivers and then subsequently overdeepened by ice movement; this is suggestive of topographical development before 34 million years ago, when mean summer temperatures were about 3 °C.