The name was well-chosen. Researchers divide the Antarctic Ice Sheet into three smaller parts. Vostok Station sits on the last of these. Because again "Vostok" means "east," that makes perfect sense. While reviewing seismic data that was gathered in the s, Russian geographer Andrey Kapitsa began to suspect there might be a huge liquid lake hiding under the East Antarctic Ice Sheet, somewhere around Vostok Station.
Scientists can use penetrating radar to measure an ice sheet's thickness. First, high-energy radio waves are sent through glaciers, ice sheets or ice caps. If any echoes bounce back, they might reveal important info about the frozen water's structural makeup. Back in the s and s, this technology started finding subglacial lakes across Antarctica. It turned out Kapitsa's hunch was right on the money.
A radio-echo survey, and measurements taken via satellite, eventually confirmed there's a giant lake buried near Vostok Station. The journal Nature announced this discovery on June 20, More than 2 miles , or nearly 4 kilometers, of ice separate Lake Vostok as it's come to be known from the surface. Human hands have never touched it, but seismometers and ice-penetrating radar have given us a decent picture of the lake.
We know it's got an elongated shape. Even though Lake Vostok is around miles kilometers in length, it's only 31 to 50 miles 50 to 80 kilometers wide. There's both a northern and a southern basin. Experts say the lake is up to 2, feet meters deep at certain points.
Network Germany. Network Italy. Network East Africa. Network China. Living Lakes Webinars. Gigantic freshwater lake found unter 4 km of ice Almost 4 km beneath the East-Antarctic ice sheet, Lake Vostok, a vast freshwater lake was discovered by using ice-penetrating radar and artificial seismic waves. The purest lake in the world — a victim of science? The Russian scientist who is leading an effort to analyse samples from a lake buried under almost 4 kilometres of Antarctic ice has hit back against criticism that an unknown species of bacterium discovered by the team was in fact contamination.
But other researchers argue that announcement was premature because the bacterium might just have been a contaminant from the drilling fluid. But Bulat stands by the claim, and says that the team took steps to rule out potential contamination. The Russian team broke through into the pristine lake in February A preliminary analysis, reported last October, suggested that the upper layers of the lake were lifeless.
But tests carried out since have revealed that this is not the case, says Bulat. Genetic analysis has revealed three variants of the bacterium that cannot be assigned to bacterial lineages described in global databases, he says. More sophisticated tests, including whole-genome sequencing, will be required to answer these and other questions, says Bulat.
However, he says, the high level of contamination — the current samples contain as much drill fluid as lake water — and the meagre numbers of bacteria, just cells per millilitre, mean that these analyses cannot yet be done.
Other researchers say that they would be surprised if Lake Vostok is totally devoid of life. Some scientists think the ridge could be a hydrothermal vent, similar to the ocean floor black smokers that teem with tubeworms. The long, narrow lake may lie in a rift valley, similar to Lake Baikal in Russia. Geothermal heat from the Earth keeps the temperature of the lake water hovering around 27 degrees Fahrenheit minus 3 degrees Celsius , scientists believe.
The weighty pressure of the overlying ice keeps the lake liquid despite its below-freezing temperature. In the s, Christner was part of an international team that discovered microbes in frozen lake water collected above Lake Vostok's liquid surface, called accretion ice.
The top half-inch 1 centimeter of the lake surface freezes onto the flowing ice sheet above the lake, scientists think. Analysis of the life forms suggests Lake Vostok may harbor a unique ecosystem based on chemicals in rocks instead of sunlight, living in isolation for hundreds of thousands of years. More recent studies of genetic material in Vostok's accretion ice revealed snippets of DNA from a wide variety of organisms related to single-celled creatures found in lakes, oceans and streams.
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