L. M. Savatyugin, S. R. Verkulich, V. N. Masolov, A. N. Sheremetiev, V. Ya. Lipenkov, S. S. Abyzov, S. A. Bulat, N. I. Barkov, I. N. Kuzmina. The sub-glacial Vostok lake, antarctica: results and perspectives of geophysical, glaciological and microbiological investigations
The results of sub-glacial Vostok lake investigations, carried out during the last three years by Russian scientists, are presented. The geophysical measurements reveal morphological characteristics of the lake basin and main parameters of the lake: the thickness of glacier above the lake varies from 3750 to 4260 m, the lake extension is not less than 300 km, the lake water layer thickness is up to 1200 m, and the thickness of lake bottom sediments is up to 300 m. The glaciological investigations of ice core from the borehole 5G-1 (Vostok Station) proved the lake genesis of ice in the glacier horizons deeper than 3538 m, allowed to estimate the average isotopic composition of lake water (δD=-449,3‰; δ18O=-57,9‰), the dissolved oxygen concentration in lake water (between 27 and 1,3•103 mg L-1) and allowed to assume the lake water older than 1 million years. The microbiological investigations proved presence of microorganisms in the re-frozen lake ice (including "lake" bacteria), and allowed supposing an existence of hydrothermal vents nearby surface sediments of the lake.
It is planned, that further geophysical, glaciological and microbiological investigations, as well as coring and sampling of additional 50 m of the accreted ice from the borehole 5G-1 are planned.