The hypothesis of tectonic preglacial genesis of the basin and water body of Antarctica’s Lake Vostok
V.V. LUKIN1,2, A.N. MARKOV3,4
1Arctic and Antarctic Research Institute, St. Petersburg, Russia
2St. Petersburg State University, St. Petersburg, Russia
3China University of Geosciences, School of Geophysics and Information Technology, Beijing, China
4Jilin University, Polar Research Center, Changchun, China
Keywords: Gondwana, paleotectonics, rift genesis, geothermal flows, vertical water stratification, origin of the water body and bottom sediments
Abstract
A brief history of the latest major geographical discovery of the 20th century: subglacial Lake Vostok in Antarctica, is considered. The contribution of Russian and British scientists to this milestone event is analyzed. The article estimates the scientific importance and the need to study the unknown hydrological object located under the glacial strata of more than 3700 m in thickness, the habitat of microbial variety under the conditions of chemosynthesis as well as testing scientific and engineering technologies for space projects in the search for life. It is indicated that the Antarctic community has approved the Russian comprehensive environmental evaluation of environmental effects of the project for unsealing the glacier above Lake Vostok. The role of subglacial lakes in Antarctica’s hydrology is determined, and the hypotheses of their origin are considered: the possibility for glacier melting at its lower surface and tectonic formation of lacustrine valleys and water in them before glaciation of the sixth continent. Based the results of paleotectonic studies in Antarctica and India and taking into consideration the analysis of the size and topography of the Lake Vostok valley, it is concluded that it has a rift-related origin. This geological process is characteristic of the period of splitting of the Gondwana supercontinent that began 130-140 million years ago. This is evidence of a high likelihood that the water body of Lake Vostok came into existence prior to Antarctica’s drift toward high latitudes of the southern hemisphere. It is concluded that Lake Vostok had appeared long before the beginning of glaciation of Antarctica 35-40 million years ago and, accordingly, that the age of strata of water and bottom sediments of Lake Vostok is much more ancient than the age of the glacier located above it. The results obtained indicate that a scientific study of this lake is more promising than the search for the most ancient ice on Earth with the maximum supposed age of only up to 1,5 million years.
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