Scientists may have solved the mystery of how and when an enigmatic mountain range buried deep beneath the East Antarctic ice sheet formed.

The Gamburtsev Subglacial Mountains have puzzled scientists since their discovery in 1958.

The continent's so-called 'ghost mountains' lie beneath the ice sheet that surrounds Dome Argus, the highest ice feature in Antarctica.

Recent radar studies show the area is cut into jagged mountain ranges and valleys, similar in size and shape to the European Alps.

But this kind of topography is usually associated with recently uplifted features, not those found in the middle of ancient and geologically inactive continents.

Now detailed geophysical mapping by an international team of researchers led by Dr Fausto Ferraccioli from the British Antarctic Survey provides the first comprehensive view of the mountains' architecture and possible origins.

Dr Ferraccioli and his team's research is published today in the journal Nature.

Fossil rift valley

The researchers used magnetic, radar and gravity data from extensive aerial surveys combined with dating evidence from zircons taken from core samples and other sediments to create a model that explains the Gamburtsev's origins.

"The model suggests that a collision of continents about 1 billion years ago produced a thick crust, uplifting the Gamburtsev region and producing high mountainous topography," says Emeritus Professor John Veevers, from the ARC National Key Centre for Geochemical Evolution and Metallogeny of Continents (GEMOC) at Macquarie University.

Professor Veevers was not involved in the study but wrote a commentary on the finding in the same issue of Nature.

"This uplifted area collapsed under its own weight and was worn almost flat by erosion, while the underlying crustal base (known as the root) remained intact," he said.

"Then rifting, where the Earth's crust is gradually pulled apart occurred about 250 million years ago during the Permian period, and again 100 million years ago, causing the formation of an extensive rift valley system similar to the Great Rift Valley in East Africa."

The sub glacial lakes in Antarctica also resemble the rift lakes of East Africa.

Further uplifting of the region continued as the Earth's crust rebounded following the release of pressure associated with rift processes and unloading of weight through continued erosion.

"The early uplift, about 250 million years ago, is revealed by a pattern of rivers that drain outward from an ancestor of the Gamburtsevs into Antarctica, Africa, and India, which were joined together at this time," Professor Veevers added.

"The river sands contain the plant fossil Glossopteris of Permian age.

"Erosion, first by rivers and later by the first glaciers around 34 million years ago then carved the steep peaks and valleys into the Gamburtsev," he said.

"Finally, around 14 million years ago, this rugged topography was frozen in time by the growth of the East Antarctic Ice Sheet, where its discovery came as a big surprise."