Posts Tagged ‘Antarctica’

Piece of crust stolen from Texas found in Antarctica

29 Aug

You’ve likely heard of Pangaea (not the one that sounds similar from Avatar), but you may not realize that it wasn’t the first supercontinent; several have been identified from the rock record. About a billion years ago, a supercontinent named Rodinia formed from the collision of a number of cratons which comprise parts of today’s continents. Evidence of the collisions that built Rodinia remains in a geological remnant called the Grenville mountain range.

Collisions of continents compress the crust between them, driving up a range of mountain peaks. We see a process like this going on today in the Himalayas, where the Indian plate is pushing northward into the Eurasian plate. With time, however, erosion will level out these mountains.

The Appalachian mountain range no longer reaches the impressive heights it once did because it has been eroding for over 400 million years. Deep in the roots of the Appalachians, though, we can see evidence of an even older mountain range that has long-since eroded from sight. The remnants of the Grenville range extend along the East Coast of the United States, but also continuing north into Canada as well as south through Texas and into Mexico. 

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Drill Close to Reaching 14-Million-Year-Old Antarctic Lake

07 Jan

By Duncan Geere, Wired UK

Lake Vostok, which has been sealed off from the world for 14 million years, is about to be penetrated by a Russian drill bit.

The lake, which lies 2.5 miles below the icy surface of Antarctica, is unique in that it’s been completely isolated from the other 150 subglacial lakes on the continent for such a long time. It’s also oligotropic, meaning that it’s supersaturated with oxygen: Levels of the element are 50 times higher than those found in most typical freshwater lakes.

Since 1990, the Arctic and Antarctic Research Institute in St. Petersburg in Russia has been drilling through the ice to reach the lake, but fears of contamination of the ecosystem in the lake have stopped the process multiple times, most notably in 1998 when the drills were turned off for almost eight years.

Now, the team has satisfied the Antarctic Treaty Secretariat, which safeguards the continent’s environment, that it’s come up with a technique to sample the lake without contaminating it. Valery Lukin told New Scientist: “Once the lake is reached, the water pressure will push the working body and the drilling fluid upwards in the borehole, and then freeze again.” The next season, the team will bore into that frozen water to recover a sample whose contents can then be analysed.

The drill bit currently sits less than 328 feet above the lake. Once it reaches 65 to 98 feet, the mechanical drill bit will be replaced with a thermal lance that’s equipped with a camera.

Time is short, however. It’s possible that the drillers won’t be able to reach the water before the end of the current Antarctic summer, and they’ll need to wait another year before the process can continue.

When the sample can be recovered, however, it’s hoped that it’ll shed light on extremophiles — lifeforms that survive in extreme environments. Life in Lake Vostok would need adaptions to the oxygen-rich environment, which could include high concentrations of protective enzymes. The conditions in Lake Vostok are very similar to the conditions on Jupiter’s moon Europa and Saturn’s moon Enceladus, so the new data could also strengthen the case for extraterrestrial life.

Finally, anything living in the lake will have evolved in relative isolation for about 14 million years, so it could offer a snapshot of conditions on Earth long before humans evolved.

Updated 5:12 pm ET.

Image: Antarctica, with location of Lake Vostok circled in red.


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Duncan Geere is a senior staff writer at He can be found on Twitter at @DuncanGeere. Follow Wired at @WiredUK