Gamburzew Mountains
| Gamburzew Mountains | ||
|---|---|---|
| Highest peak | (unnamed) ( 3400 m ) | |
| area | East Antarctica | |
|
||
| Coordinates | 81 ° S , 76 ° E | |
| surface | 300,000 km² | |
The gamburtsev mountain range , occasionally Gamburtsew Mountains , named after the Soviet geophysicist Grigori Alexandrovich Gamburzew (ger .: Grigoriy Aleksandrovich Gamburtsev; russ .: Григорий Александрович Гамбурцев), is a completely under the ice of Antarctica hidden, some 300,000 square kilometers extensive mountain range about 1200 km long and with highest elevations of 3400 m. It lies beneath the East Antarctic Plateau near its highest point, the Dome Argus , in the middle of East Antarctica.
exploration
During the third international polar year in 1958, the Antarctic point, which is furthest from all coasts and is known as the “ South Pole of Inaccessibility ”, was the target of a Soviet expedition . Sound waves sent underground there were the first indications of a hidden mountain range and this was named after the Soviet geophysicist Grigorij Aleksandrovič Gamburzew.
In January 2009, a team led by the geophysicist Michael Studinger from the Lamont-Doherty Earth Observatory in New York City , ( USA ), involved the Antarctica's Gamburtsev Province (AGAP) project using radar measurements and recording changes in the earth's magnetic and gravity fields Board of a research aircraft found that the flat ice deposit above these mountains is between 800 and 4000 meters thick. Under this layer of ice, a mountain shape with steep peaks, rough gorges and gentle valleys, partly filled with liquid water lakes, could be discovered, with not a single mountain peak protruding from the ice above.
Mountain erosion
The researchers have so far found that instead of a gentle, rounded hilly landscape created by the glaciers that first grew in Antarctica 35 million years ago , a mountain range of an almost alpine character with pointed peaks and many peaks that had evidently escaped erosion was found no explanation yet. The ice may have spread much faster than previously thought. What is certain is that after a solid ice sheet had formed, the landscape underneath was sealed and preserved for many millions of years.
Mountain formation
There are several theories about the formation of the Gamburzew Mountains. The alpine topography on the very old East Antarctic land mass and the likely longevity of the mountains are geologically very unusual. The most comprehensive model describes the elevation of the mountains in connection with a rift zone that is 2500 km long and surrounds the Gamburzew Mountains. Around 1 billion years ago, an original collision mountain range is said to have formed, which was then removed. A firm and dry mountain root has been preserved. At the end of the Permian approx. 250 million years ago and again in the Cretaceous 100 million years ago, a renewed uplift of the mountains took place along a rift zone that is comparable to the African rift system . Warming and pressure relief are said to have led to the uplift of the crust roots. Rivers and glaciers then formed the mountains, leaving valleys and gorges behind. The Gamburzew Mountains have been covered by ice for 34 million years and for at least 14 million years the topography of the mountains has remained almost unchanged due to the ice cover. This theory was built from magnetic , gravimetric and radar measurements.
Seismic investigations, however, reveal some contradictions. At depths greater than 200 km, very high velocities can be measured, which indicate a thick, old stable lithosphere , the deformation of which, as described above, is assessed as rather unlikely. In addition, only very small speed anomalies can be detected, which contradict a rift system like the African one. The lack of speed anomalies also contradict a heat anomaly.
Climate archive
It is estimated that under Dome Argus (Dome A), which is 4,093 meters high, the highest point on the Antarctic ice sheet, there could be ice about 1.2 million years old. A “climate archive” would thus be found there, which extends 400,000 years further into the past than the ice core of the European drilling project EPICA, which ended in 2004 . Since the beginning of 2009, a Chinese team has created the basis for a borehole as another international project, in which it set up the first part of a new research station and opened the Kunlun station on February 2, 2009 as a container village on stilts . This station is expected to be in operation all year round in five to ten years.
Space observation
Since the extreme climate of Dome Argus with its particularly dry and calm mountain air allows a crystal-clear view of space in the polar night , the unmanned plateau observatory was put into operation in 2008 .
See also
Web links
- Survey targets 'ghost' mountains BBC online
- Exploring the Gamburtsev Subglacial Mountains during the International Polar Year 2007 - 2008
- BBC: Antarctic ice sheet built 'bottom-up'
- Jagged ancient mountains under the ice. On: Wissenschaft.de from November 16, 2011.
Individual evidence
- ↑ Understanding climate processes ( Memento of October 22, 2013 in the Internet Archive ), Bundesregierung-online, February 27, 2009
- ↑ Participation in an international AGAP expedition: BGR scientists research the “Pole of Inaccessibility” in the Antarctic , BGR press release of October 15, 2008
- ↑ a b c d e Ute Kehse: Where has never been a person , Berliner Zeitung (BLZ) February 27, 2009, Wissenschaft, p. 13
- ↑ Antarctica: Mysterious Mountains under the Ice Armor. In: Spiegel Online . February 26, 2009, accessed June 10, 2018 .
- ↑ Jonathan Amos : Data to expose 'ghost mountains'. BBC , December 18, 2009, accessed December 19, 2009 .
- ↑ Ferraccioli et al., 2011: [1] East Antarctic rifting triggers uplift of the Gamburtsev Mountains
- ↑ Lloyd et al., 2013: [2] Upper mantle seismic structure beneath central East Antarctica from body wave tomography: Implications for the origin of the Gamburtsev Subglacial Mountains
- ^ Inauguration of Kunlun Station at Dome Argus , February 6, 2009
- ↑ PLATO, Dome A Robotic Observatory ( memento of the original from March 24, 2010 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice.
