A blog about sewing machine repairs,but mainly my hobbies which include old school role playing games, science fiction,films, horror, and general geekery. Sit down and stay a spell.
Friday, November 18, 2011
At The "Real" Mountains of Madness
My favorite Lovecraft book is At The Mountains of Madness! There's something out in the ice alright! Check it out!
How did a giant mountain range form beneath a mile of Antarctic ice?
The Gamburtsev Mountains are over 750 miles long and nearly 9,000 feet tall, making them roughly the same size as the Alps. But nobody has ever even seen these mountains, because they're located deep beneath the Antarctic ice sheet.
First discovered in 1958, the Gamburtsev Mountains might literally be the biggest mystery on the planet. How could a mountain range of such immense size be buried so far beneath anywhere between 2000 feet and a mile of snow and ice? It's not an easy question to answer - as Columbia geophysicist Robin Bell points out, we have plenty of rock samples from the Moon and other far distant objects, and yet none from an Alps-sized mountain range on our own planet.
As such, scientists have to rely on more indirect methods to piece together the range's origins. An international team used a mix of ice-penetrating radar, gravity meters, and magnetometers to peer through the ice and figure out the exact contours of the peaks and valleys that make up the Gamburtsevs. From this data, they've been able to piece together a likely history of Earth's only literally unclimbable mountains.
According to their research, the mountains first formed a billion years ago during a massive collisions of continents. This causes the rocks that make up the Gamburtsev Mountains to smash together, but more importantly they created a thick root deep in the crust below the mountain range. Over the ensuing hundreds of millions of years, these first Gamburtsevs were eroded away, leaving only the crustal root.
It was from that root that the new Gamburtsevs would form somewhere between 250 and 100 million years ago, as the southern supercontinent Gondwanaland broke part. This process warmed up the root, and this in turn pushed land back upwards, full of rivers and glaciers that over time carved a spectacular mountain range. The East Antarctic Ice Sheet formed about 34 million years ago and completely covered the Gamburtsevs, protecting from further erosion but leaving them completely hidden from the rest of the world.
Robin Bell explains this remarkable process:
"It has been almost a billion years since the Gamburtsev first formed. This work shows that very old mountains can rise again, like a Phoenix from the ashes. The Gamburtsevs rose from the long eroded East Antarctic craton. We are accustomed to thinking that mountain building relates to a single tectonic event, rather than sequences of events. The lesson we learned about multiple events forming the Gamburtsevs may inform studies of the history of other mountain belts."
The team next hopes to drill down to the mountains to retrieve the first actual samples from the mountains. From there, well...perhaps I spoke too soon when I declared these mountains unclimbable. If nothing else, an expedition down there would make for one hell of a movie, even if it's not possible to actually do it here in reality.
Via Nature. Top image of above-ground Antarctic mountains by eliduke on Flickr. Second image by Zina Deretsky/NSF.
So thanks to IO9 for the above article! However get this one their mounting an expediation! Now the only thing they need is a guy named Dyer!
Expedition set for 'ghost peaks'
By Jonathan Amos Science reporter, BBC News
Working deep in the interior is challenging at the best of times
It is perhaps the last great Antarctic expedition - to find an explanation for why there is a great mountain range buried under the White Continent.
The Gamburtsevs match the Alps in scale but no-one has ever seen them because they are covered by up to 4km of ice.
Geologists struggle to understand how such a massif could have formed and persisted in the middle of Antarctica.
Now, an international team is setting out on a deep-field survey to try to get some answers.
The group comprises scientists, engineers, pilots and support staff from the UK, the US, Germany, Australia, China and Japan.
It's rather like being an archaeologist and opening up a tomb in a pyramid and finding an astronaut sitting inside. It shouldn't be there
Dr Robin Bell, Lamont-Doherty Earth Observatory
The ambitious nature of the project - working in Antarctica's far interior - has required an exceptional level of co-ordination and co-operation.
"You can almost think about it as exploring another planet - but on Earth," said Dr Fausto Ferraccioli from the British Antarctic Survey.
"This region is a complete enigma. It's in the middle of the continent. Most mountain ranges are on the edges of continents, and we really can't understand what these mountains are doing in the centre."
The AGAP (Antarctica's Gamburtsev Province) project will establish two camps from where the team will map the subglacial range using surface and airborne instruments.
EXPLORING THE SUBGLACIAL GAMBURTSEV MOUNTAINS
1. Aircraft will use radar to detect ice thickness and layering, and to map the shape of the deeply buried bedrock
2. The planes will also conduct gravity and magnetic surveys to glean more information about the mountains' structure
3. By listening to seismic waves passing through the range, scientists can probe rock properties deep in the Earth
Dr Fausto Ferraccioli describes the equipment onboard the aircraft
The Gamburtsevs were discovered by a Soviet team making a seismic survey on a traverse across the ice in the late 1950s. The hidden rocky prominence was totally unexpected; scientists thought the interior of the continent would be relatively flat.
"There are two easy ways to make mountains," explained Dr Robin Bell, from the Lamont-Doherty Earth Observatory, who is a lead US researcher on the expedition.
"One is colliding continents, but after they collide they tend to erode; and the last collision was 500-million-plus years ago. They shouldn't be there.
Dr Robin Bell says it will be like doing an "X-ray of the ice sheet"
"The other way is a hotspot, [with volcanoes punching through the crust] like in Hawaii; but there's no good evidence for underneath the ice sheet being that hot.
"I like to say it's rather like being an archaeologist and opening up a tomb in a pyramid and finding an astronaut sitting inside. It shouldn't be there."
The mountains are believed to have been a key nucleation point for the vast East Antarctic Ice Sheet.
It is thought that as Earth's climate cooled just over 30 million years ago, the snows that fell on the mountains produced mighty glaciers, which then merged to form one giant spreading ice-mass.
A better understanding of these events could give clues as to how Antarctica might evolve in the coming centuries if, as expected, the Earth continues its current warming trend.
The AGAP project is a flagship endeavour of International Polar Year - the global science community's concerted push to try to answer the big questions about the Earth's northern and southern extremes.
The challenging nature of the expedition has required that expertise be drawn from across the polar community. Supplying such remote camps is a major logistical exercise; working in them - at temperatures 30-40 degrees below zero Celsius - is bound to be physically demanding.
Two survey aircraft will sweep back and forth across the ice to map the shape of the mountains. The planes will be equipped with ice-penetrating radar and instruments to measure the local gravitational and magnetic fields.
Air bubbles trapped in old ices record environmental conditions
Information on the deeper structure of the Gamburtsevs will come from a network of seismometers that will listen to earthquake signals passing through the rock from the other side of the globe.
"We'll map everything from the detailed ripples on the surface of the ice sheet down to the temperature structure hundreds of kilometres in the Earth, so we'll have everything from the layering in the ice to what the nature of the rocks are," said Dr Bell.
Another important aim of the project is to find a place to drill for ancient ices. By examining bubbles of air trapped in compacted snow, it is possible for researchers to glean details about past environmental conditions.
Not only can they see concentrations of carbon dioxide and methane - the two principal human-produced gases now blamed for global warming - but they can also gauge past temperatures from the samples.
Somewhere in the Gamburtsev region there could be a location were it is possible to drill down to ices that are more than a million years old. This is at least 200,000 years older than the most ancient ices currently in the possession of scientists.
The expedition gets under way in the next few weeks and will take some two-and-a-half months to complete.