Posts Tagged ‘Antarctic ice’
Young mountains on an old continent — Gamburtsev range solved
Scientists say they can now explain the existence of what are perhaps Earth’s most extraordinary mountains.
The Gamburtsevs are the size of the European Alps and yet they are totally buried beneath the Antarctic ice. Their discovery in the 1950s was a major surprise. Most people had assumed the rock bed deep within the continent would be flat and featureless.
Survey data now suggests the range first formed over a billion years ago, researchers tell the journal Nature.
The Gamburtsevs are important because they are thought to be the location where the ice sheet we know today initiated its march across Antarctica. Unravelling the mountains’ history will therefore inform climate studies, helping scientists to understand not just past changes on Earth but possible future scenarios as well…
This multinational effort in 2008/2009 flew aircraft back and forth across the east of the White Continent, mapping the shape of the hidden mountain system using ice-penetrating radar. Other instruments recorded the local gravitational and magnetic fields, while seismometers were employed to probe the deep Earth.
The AGAP team believes all this data can now be meshed into a credible narrative for the Gamburtsevs’ creation and persistence through geological time…
“This research really solves the mystery of how you can have young-looking mountains in the middle of an old continent,” said US principal investigator Dr Robin Bell from the Lamont-Doherty Earth Observatory of Columbia University.
“In this case, the original Gamburtsevs probably completely eroded away only to come back, phoenix-like. They’ve had two lives,” she told BBC News…
The search also goes on for a suitable place in the range to drill for ancient ice.
By examining bubbles of air trapped in compacted snow, it is possible for researchers to glean details about past environmental conditions, including temperature and the concentration of gases in the atmosphere such as carbon dioxide.
Somewhere in the Gamburtsev region there ought to be a location where ices can be retrieved that are more than a million years old. This would be at least 200,000 years older than the most ancient Antarctic ice cores currently in the possession of scientists.
RTFA. Please. Another interesting addition to paleo-climatology and geology.
The past is always prologue – in the physical sense as well as metaphor.
Thanks, Ursarodinia
