The last unmapped white space of the map of the planet is Antarctica's Gamburtsev mountains, a subglacial mountain range discovered by the 3rd Soviet Antarctic Expedition in 1958 and is named for Soviet geophysicist Grigoriy A. Gamburtsev.
“These are mountain ranges that formed by the collision of tectonic plates,” said Dr Michael Studinger from the Lamont-Doherty Earth Observatory (LDEO) of Columbia University, New York.
and one of the leading scientists on the Antarctica’s Gamburtsev Province project,
The mountains were discovered by the Soviet team during the International Geophysical Year in 1957-8. Their detection was a complete surprise because the rock bed in the middle of the Antarctic continent was assumed to be relatively flat. It led some scientists to speculate that the Gamburtsevs might be old “hot spot” volcanoes that had punched their way through the Earth’s crust, much like the Hawaiian islands have done in the middle of the Pacific.
The international team spent two months in 2008/9 surveying the Gamburtsevs in Antarctica - a series of peaks totally buried under the ice cap. The shrounded Alp-like range is some 750 miles long, with jagged peaks the mountains are believed to be 8,900 ft high, completely covered by over 600 2,000 feet of ice and snow. The Gamburtsev Mountain Range is currently believed to be about the same size as the European Alps, and it is still unknown how the mountains were formed, though the current speculated age of the range is over 34 million years and possibly 500 million years.[
The range is being mapped by the Antarctica's Gamburtsev Province project,which has produced some awesome science often at brutal –80C conditions. AGAP aircraft flew a total of 120,000 miles in 2007-8 to map the area, gathering gravity, radar, magnetic and ice layer information.
The survey data revealed a very rugged landscape with high peaks and deeply incised valleys which have been worked in the past by both river and ice processes. "Before we had this data we couldn't see the valleys and therefore we had no way of being able to quantify the role of glacial and fluvial processes which is key to understanding cryosphere and climate evolution," said Dr Fausto Ferraccioli from the British Antarctic Survey.Studying what happened in these valleys could give clues as to how fast the Gamburtsevs became encased in ice.
"We're really excited about being able to use this dataset to see how valleys that were carved by rivers and then overprinted by glaciers are now driving waters underneath the ice sheet."
In addition, Dr Ferraccioli said it was possible a location could be found where ices might be drilled to retrieve information on the ancient climate of Antarctica. "There could be ice that is older than 1.2 million years - somewhere between 1.2 and 1.5 million years," he told BBC News. "We will have to do an analysis of the ice layers. But I think it's going to be quite a challenge because the topography is very rough and the layers are quite buckled."
Two instrumented Twin-Otter aircraft were flown out of remote field camps and collected a range of data. They crisscrossed the hidden peaks, flying a total of 120,000km. They gathered gravity, magnetic and ice thickness information, took radar images of the rock bed and the layers within the ice; and made a map of the ice-sheet's surface with a laser.
"We have now reached a point in the data processing that allows us to start scientific work with the data," Dr Studinger told BBC News. The science and mapping team has discovered ice that reaches down 4800 metres compared to Mount Everest's 6193.6 metres.
The mountains appear to be are filling in some major gaps in the understanding of the history of the continent. Antarctica was a standard-model continent in the days of the dinosaurs. Before Australia broke off, it's believed that the Antarctic was like modern-day Scandinavia, with cold seasons and long days and nights. The mountains are thought to have acted as the areas of formation of the modern ice sheets, which are only 30 million years old.
One of the more interesting in a long list of interesting discoveries is the finding of some free water within the deep ice. The geophysical properties of these areas aren't clear, and there's likely to be some new science involved in explaining their structure and formation.
These discoveries are only the beginning. AGAP's scientists have a lot of work to do, just analyzing this data. The AGAP survey represents a new benchmark in earth sciences, a truly tough piece of work which has redefined both the capabilities and the importance of geological survey and science.
Casey Kazan
http://www.digitaljournal.com/article/284141
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