[Ocean Drilling Program Leg 183 to the Kerguelen Plateau]
IN THE REMOTE southern Indian Ocean, straddling the Antarctic Polar Front, lies a mostly submarine plateau one-third the size of the contiguous United States. The Kerguelen Plateau is one example of a unique type of Earth feature, a large igneous province (LIP). One of the least understood features in the ocean basins, LIPs are believed to be the surface manifestations of massive pulses of volcanism that originated deep within Earth's mantle in association with narrow upwelling systems, known as mantle plumes or hotspots. The episodic nature of LIP eruptions documented in the geologic record, especially between 150 and 50 million years ago, is evidence that a more dynamic, unpredictable mode of mantle circulation, very different from that driving present-day plate motions, existed during Earth's past. LIPs preserve a record of mantle dynamics and may have also affected the Earth's environment in the past by potentially altering ocean circulation, climate conditions and sea level.
RESULTS. Surprising evidence recovered on Leg 183 revealed that the Kerguelen plateau had existed as a large landmass above sea level at three different times during an 80 million year period, before finally become submerged about 20 million years ago. The evidence consists of dark brown sediment overlying subaerially erupted lava flows, charcoal and wood fragments in sediments overlying igneous rocks, and conglomerates, which formed from sediments deposited in river beds, interlayered with lava flows. The final stage of volcanism forming the Kerguelen LIP produced magmas rich with gases such as carbon dioxide, oxides of sulfur, and water vapor, which may have caused global environmental change.
A link to a LARGE map : http://upload.wikimedia.org/wikipedia/comm...-Topography.jpg
The Kerguelen Plateau was formed starting 110 million years ago from a series of large volcanic eruptions. The presence of soil layers in the basalt with included charcoal and conglomerate fragments of gneiss indicate that much of the plateau was above sea level as what is termed a microcontinent for three periods between 100 million years ago and 20 million years ago.
The so-called Kerguelen continent might have had tropical flora and fauna about 50 million years ago. The Kerguelen continent finally sank 20 million years ago and is now 1 – 2 km below sea level. It has sedimentary rocks similar to the ones found in Australia and India, suggesting they were once connected.
And here it comes (lol) :
Could we eventually uncover a lost civilization on the sunken Kerguelen continent? And if so, what might have been its fate?
By around 110 million BC the first portions of the Kerguelen island continent had appeared. Large portions of the island continent would remain dry land for millions of years, after which they would all eventually submerge to become one with the sea floor again (with the last disappearing from the surface around 20,000,000 BC). This article lists some developments possibly relevant to the Kerguelen island continent, and any intelligent lifeforms which may have arisen or taken refuge there.
Have fun... a far older "Atlantis"..
Don't worry, it's nothing but science fiction.
It's just a possiblitiy, a civilization whiped out by time, a long time. No remnants will be discovered for the strong sea currents in that area will have whiped out anything that might give us a clue. These same currents will have flushed the top soil, and only leave an ancient, 24 millions year old rock bottom, the bootom they took samples of.
Great , eh?
From Monsters and Critics.com
Mini-continent once joined to India discovered in ocean
May 4, 2007, 22:03 GMT
Bremerhaven, Germany - A mini-continent which was formerly joined to India has been discovered deep under the southern oceans by the world's most powerful ice research vessel, German scientists said Friday.
They spoke as the ship, the Polarstern, was due to dock Saturday in its home port of Bremerhaven, Germany after a 19-month research voyage to Antarctica.
The ninth phase of the voyage was a study of the undersea Kerguelen Plateau, which was orphaned after the ancient continents separated, with India drifting away from Antarctica.
The findings suggest that the Plateau, about the size of Germany and France combined, is just the tip of a bigger piece of lost continental crust.
Geophysicists did seismic and magnetic surveys to explore the gap between the little-understood plateau and East Antarctica, the Alfred Wegener Institute of polar research in Bremerhaven said.
'This plateau was created by a massive volcanic eruption shortly after India and Antarctica separated about 120 million years ago to form the Indian Ocean,' said geophysicist Karsten Gohl.
'For the first time, we have been able to see how the succession of volcanic deposits at the southern side of the Kerguelen Plateau, which reach right to the Antarctic continent, mostly have continental crust underneath them.
'Our findings show that a continental fragment of a size hitherto never suspected must have existed between India and the Antarctic.'
The data will be entered into a computer simulation to study ancient ocean currents and world climate, said Gohl, who is one of two project leaders of a worldwide study of such gaps, code-named Plates and Gates.
The Polarstern also explored the melting of the Antarctic ice shelves, which may be due to rising temperatures or salinity of deep ocean water or to volcanic activity.
The ship, which has berths for 50 scientists, hosted 450 scientists from 24 nations during its 84,000-nautical-mile voyage.
It can operate in temperatures 50 degrees below Celsius and steam without stopping through 150-centimetre ice.
© 2007 dpa - Deutsche Presse-Agentur
© Copyright 2007 by monstersandcritics.com.
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What is a Submerged Continent?
Question and Answer: What is a Submerged Continent?
The term "submerged continent" is most often heard in association with the legendary lands of Atlantis or Mu. Atlantis and Mu never really existed, but there are a couple of real submerged continents around the world. Both are in the Southern Hemisphere. The submerged continents go by the names of Zealandia and the Kerguelen Plateau.
Zealandia is the largest of the two submerged continents, with a surface area of 3.5 million square kilometers, larger than Greenland and almost half the size of Australia. As its name suggests, the only part of the continent above water today are the islands of New Zealand. Zealandia quickly sunk when it broke off from Australia/Antarctica 83 million years ago. About 25 million years ago, Zealandia was completely underwater. Today, 93% is still underwater, with just 7% making up the New Zealand of today, which was created through tectonic action about 23 million years ago. Most of the submerged continent is less than 500 m (1,640 ft) below the surface.
Another submerged continent, far to the west, is called the Kerguelen Plateau or just Kerguelen. The continent is named after the Kerguelen islands, which along with Heard Island and the McDonald Islands are the only portions of the continent above the surface. Kerguelen is located in one of the regions of the world's oceans furthest from dry land, about 3,000 km southwest of Australia (1,864 mi) and 5,000 km (3,100 mi) south of India. Like Zealandia, Kerguelen was once part of the massive continent Gondwana, which was made up of practically all land masses in the present Southern Hemisphere. Kerguelen is smaller than Zealandia, with a surface area slightly larger than a million square kilometers, about three times the size of Japan. More than 99% of the continent is underwater.
Kerguelen began forming 110 million years ago, over the Kerguelen hotspot. Between 100 million years ago and 20 million years ago, the continent was above sea level three times, and may have had tropical flora and fauna 50 million years ago. Because of its size, Kerguelen is called a microcontinent. Kerguelen sank 20 million years ago and now lies 1-2 km (0.6 - 1.2 mi) below the ocean.
Edited by Abramelin, 17 June 2009 - 07:04 PM.