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Dry Valleys – Antartica


Wonders of the World ::--Ancient 7 Wonder||Medieval 7 Wonder||Modern 7 Wonder||Natural 7 Wonder||Wonder of Underwater||Wonder of Industrial||Wonder didn't know Existed||Human with Diffrent||20 Strange Place's||


Top Twenty Strangest Places on Earth ::--1.Socotra Island – Yamen|| 2.Salar De Uyuni – Bolivia|| 3.Kliluk, the Spotted Lake – Canada|| 4.Dry Valleys – Antartica|| 5.Rio Tinto – Spain|| 6.Blood Pond Hot Spring – Japan|| 7.The Richat Structure – Mauritania|| 8.Vale De Lua – Brazil|| 9.The Stone Forests – China|| 10.Eisriesenwelt Ice Caves – Austria|| 11.Fly to Outer Space - Virgin|| 12.Ski Dubai - UAE|| 13.Village of Unmarried People, Barwaan Kala - India|| 14.Montreal's underground city - Canada|| 15.Pitcairn Islands|| 16.Cappadocia - Turkey|| 17.Pamukkale - Turkey|| 18.Hell's Door- Turkmenistan (Derweze)|| 19.The Great Blue Hole - Belize|| 20.Blood Falls - Antarctica||


McMurdo Dry Valleys

Under the ice layer there is very salty water and unknown creatures studied by most of the researchers around the world:

The McMurdo Dry Valleys are a row of snow-free valleys in Antarctica located within Victoria Land west of McMurdo Sound. The region is one of the world's most extreme deserts, and includes many interesting features including Lake Vida and the Onyx River, Antarctica's longest river.



The Dry Valleys of Antarctica get virtually no snowfall or moisture of any kind. Researchers come not only to study one of the world's most delicate, yet simple ecosystems, but also to learn more about the unique geological formations and processes occurring there. From south to north, the principal ice-free valleys include the Taylor, Wright, McKelvey, Balham, Victoria, and Barwick Valleys. Similar but smaller valleys also occur farther south, along the coast of McMurdo Sound and the western margin of Koettlitz Glacier; these include, from south to north, Miers, Marshall, and Garwood Valleys, and the Salmon Stream valley.



The major Dry Valleys have certain characteristics in common, and some have unique features. They are generally 5-10 kilometers wide (between ridge crests) and 15-50 kilometers long. Only the Taylor and upper Wright Valleys have glaciers at their heads, which connect with the ice of the polar plateau; the other valleys have either barren upper reaches or small alpine glaciers. Only Taylor Valley exits directly to the sea ice of McMurdo Sound, whereas the others are blocked by the Wilson Glacier.

Several lakes occupy parts of some valley floors, their surfaces frozen most of the year. Some lakes are over 30 meters deep and have perennial ice covers several meters thick.Lake Vanda, which is typical, has 10 percent dissolved solids content in its lower few meters--three times as saline as sea water-while the upper 50 meters has only 0.1 percent. Scientists have noted high water temperatures in the lakes, with temperature inversions resulting in bottom waters as warm as 25°C .These high temperatures are due entirely to solar heating of the water through the ice, and not to any heat from rocks at depth beneath the lakes.

The lakes are by far the most interesting and diverse habitats in the Dry Valleys. Organisms are found growing on and in the ice cover, in the water, and on the bottom of the lakes. Exploration of lake bottoms by SCUBA-equipped divers, including core sampling of bottom sediments, have disclosed the existence of algal mats on lake floors; in certain respects these are analogous to some of the Earth's earliest life forms. The mats produce gases which render them buoyant in marginal zones of the lake. There they form columns, which detach from the bottom, rise, and then work their way upward through the surface ice layers-as much as 5 meters thick-after which they dry out and blow away, sometimes to colonize in other locations.


antarctica dry valley

Glacier-Scoured
  • Antarctic Dry Valley glaciers are clean and white, with a minimum of rock debris, few crevasses, and near-vertical terminus walls.
  • This is due largely to the relatively dry-based nature of these Antarctic glaciers and the fact that they do not move by slipping and sliding on the underlying bedrock, but more by shearing and plastic flow within the ice itself.
  • Also, at such low temperatures, the ice is not able to incorporate rock debris by the pressure-induced melting common to glaciers in temperate climates.
  • The dry valleys are strange: except for a few steep rocks they are the only continental part of Antarctica devoid of ice. Located in the Trans-Antarctic Range, they correspond to a mountain area where evaporation (or rather, sublimation) is more important than snowfall, thus all the ice disappears, leaving dry barren land.

     

    Here a glacier coming from the continental ice field flows down the valley and just dries out. In summer there can be rivers in the Dry Valleys. Moss and some other form of vegetation grow. Some lakes have strange characteristics, like lake Vanda, always covered with ice, but with salt-saturated liquid water underneath and very mysterious biology. Mummified bodies of seals have been found in those parts, hundreds of kilometers from the sea.

     

    The Dry Valleys are a favorite exploration spot for geologists and microbiologists. I've never been there, those pictures were taken by Laura Connor and Effie Jarret who flew over them several times during their remote sensing missions.


     

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