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Meteorite crater reveals future of a globally warmed world

The future of a globally warmed world has been revealed in a remote meteorite crater in Siberia, where lake sediments recorded the strikingly balmy climate of the Arctic during the last period when greenhouse gas levels were as high as today.
The sediments have been slowly settling in Lake El'gygytgyn since it was formed 3.6m years ago, when a kilometre-wide meteorite blasted a crater 100km north of the Arctic circle. Unlike most places so far north, the region was never eroded by glaciers so a continuous record of the climate has lain undisturbed ever since.

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Remote Siberian Lake Holds Clues to Arctic--and Antarctic--Climate Change

Intense warm climate intervals--warmer than scientists thought possible--have occurred in the Arctic over the past 2.8 million years.
That result comes from the first analyses of the longest sediment cores ever retrieved on land. They were obtained from beneath remote, ice-covered Lake El'gygytgyn (pronounced El'gee-git-gin) ("Lake E") in the northeastern Russian Arctic.

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Arctic Lake Yields Planet's Most Continuous Record of Ancient Climate

It took the better part of a decade, $10 million, and help from the guys who build ice roads for Canadian truckers. But scientists now have the most continuous record of ancient climate ever extracted from the terrestrial Arctic.
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Title: FIRST COLLABORATIVE RESULTS FROM LAKE EL'GYGYTGYN CRATER: PROXIES OF CHANGE SINCE 3.6 MA, NE RUSSIAN ARCTIC
Authors: BRIGHAM-GRETTE, Julie, Dept Geosciences, Univ of Massachusetts, Amherst, MA 01003, juliebg@geo.umass.edu, MELLES, Martin, Geology, University of Cologne, Cologne, 50674, Germany, MINYUK, Pavel, Northeast Interdisciplinary Scientific Research Institute, RAS, Magadan, 00, Russia, KOEBERL, Christian, Department of Lithospheric Research, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria, also of the Natural History Museum, Burgring 7, A-1010 Vienna, Austria, and LAKE E SCIENTIFIC PARTY, Entire, Multiple Cities, 01003

Lake El'gygytgyn in NE Russia is a meteorite crater formed 3.6 Myr ago in northeast Russia, 100 km north of the Arctic Circle (67°30' N, 172°05' E). Drilling in spring 2009 recovered a sediment record reaching 315 m below lake floor capturing changes in limnological properties recording elements of climate change across the western Arctic. The geochronology, so far, is based on paleomagnetic properties measured from U-channels and core catcher samples tuned to precession but anchored by more than 10 tephra units, OSL, and pollen stratigraphy. More than 50 international scientists - faculty and graduate students are jointly involved in the labor intensive, analytical aspects of core processing.
The lowest 15 meters of the sediment record appear to be barren based on core catcher samples so far analysed. This may be due to the intense heat of the post-impact environments. Preliminary pollen analysis of the Pliocene section indicates that environmental conditions were not uniformly warm but that cool and warm cycles were characterised by the presence of tree pollen, providing a compositional idea of Pliocene El'gygytgyn forests of alder (Alnus), hemlock (Tsuga), fir (Abies), spruce (Picea) and tree pine (Pinus), not just shrubs. Larch pollen is a common element in the record. ITRAX scanning, colour spectra, FTIRS, and diatom analyses demonstrate that past interglacials were not uniform in intensity at this high latitude site. Rather, isotope stages 9 and 11 are remarkable in intensity, stronger than other proxies for stages 5e. Core processing and lithological characterization is ongoing but our initial results confirm the continuous nature of the paleoclimate record and the representative nature of this site for understanding change across the western Arctic. Whether Arctic climate changed in steps, jolts or plunges at glacial/interglacial transitions and the onset of Northern hemisphere glaciation will only come from study of the continuous record over the coming year.

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An important goal of the sea drilling was the drilling of the impact breccias. This clastic rock created by a meteorite impact was found 315 metres below the sea bottom. The cores drawn by drilling 200 metres into the breccias are invaluable.

"We expect new insights not only about the trajectory and composition of the meteorite, but particularly about the reactions of the volcanic rocks to the impact" - Christian Koeberl from the University of Vienna, who coordinates the international team processing the impact rocks. The insights serve the risk assessments in areas with similar rock formations.

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Scientists Return from Expedition to Drill Beneath Frozen Russian Lake
Lake Elgygytgyn was created 3.6 million years ago when a meteor more than a half-mile wide hit Earth and formed an 11-mile wide crater.

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Success of International Scientific Drilling Project at the El'gygytgyn Meteorite Impact Crater (Arctic Russia): Christian Koeberl studies 3.6-Million-Year-Old Impactites

Christian Koeberl, head of the Department of Lithospheric Studies at the University of Vienna (Austria), has recently returned from an expedition to Arctic Siberia. He is one of the principal investigators of a drilling project at the El'gygytgyn meteorite impact crater that is coordinated by the International Continental Scientific Drilling Program (ICDP) and that was recently successfully concluded. The main goals of the project are to obtain, from analyses of the drill cores, new information the formation of the impact crater, as well as to derive a climate history of the Arctic. The investigation of the impact breccia drill cores will be coordinated by Christian Koeberl, and studies in Vienna will be funded by the Austrian Science Foundation FWF.

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The afternoon of April 14, Martin and the German grad student hit pay dirt.
As the rig, much like an oil drill, boomed away for another 12-hour shift, Martin slid out one more plastic tube, much like all the others. But inside, instead of ice or sediment, there was rock.
Immediately, a radio call went out. The $10 million mission had been accomplished.

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In the next few days, a convoy of bulldozers and trucks will set out from a remote airport in Siberia, heading for a frozen lake 62 miles north of the Arctic Circle, but the trip isn't a holiday visit to the North Pole. Instead, the trucks will deliver core-drilling equipment for a study of sediment and meteorite-impact rocks that should provide the longest time-continuous climate record ever collected in the Arctic.
Once in place next month, the drilling will allow an international team of geoscientists led by Julie Brigham-Grette of the University of Massachusetts Amherst and Martin Melles of the University of Cologne, Germany, to burrow back in time, retrieving core samples more than 3 million years old and answering questions about Earth's ancient past.

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The Terra satellite took this false-colour image of Lake El'gygytgyn  on August 18, 2008. In the image red indicates vegetation, grey-brown indicates bare land, and deep blue indicates water. Towards the bottom of the lake, the Enmyvaam (Enmivaam) River can be seen  flowing from the lake.

Elgygytgynb.jpg
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Credit: NASA, Jesse Allen

Lake El'gygytgyn was formed by a 3.6-million-year-old meteorite impact.  This region in the Arctic escaped widespread glaciation during the Pleistocene Ice Age. As a result, the lake bed sediments contain a continuous record of past Arctic conditions, making them extremely valuable to paleoclimate researchers.
Researchers began drilling at the crater in November 2008. The drilling project is expected to continue through to the spring of 2009. The lake bed cores will provide the longest continuous record of climate change in the Arctic.

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