PENETRATION INTO THE SUBGLACIAL ANTARCTIC WATER BODY – LAKE VOSTOK
Russian specialists were the first to penetrate the subglacial Antarctic water body, Lake Vostok, a kind of time capsule, sealed about 14 million years ago. Its waters hold secrets not found anywhere else on the planet. Prehistoric microorganisms may still exist there to this day, capable of giving mankind new knowledge about the Earth’s biosphere, and possibly about life on other planets. This event is often compared to the achievements of pioneers in space exploration.
Drilling at the Vostok Station started back in the late 1960s. At that time, ice cores were drilled for the purpose of studying paleoclimate reconstructions. Since 1970, the specialists of the Department of Well Drilling of the Leningrad Mining Institute (now the Saint-Petersburg Mining University) were engaged in this work. The unique Vostok Station drilling rigs were created exactly at the Mining Institute, one of the largest Higher Education Mining Institutes and the first Higher Technical School in Russia. The University belongs to the category National Research University in Russia (2009) and trains specialists in mining, civil, oil and gas engineering, geological prospecting of Russia and foreign countries. At the Mining University intense research is carried out on the issues of development of raw material sources of the country, rational nature management, development of progressive energy saving technologies of mining and processing of mineral resources. The University has the highest state status of educational system of Russia, being an especially valuable object of cultural heritage of peoples of Russia, it is awarded with four Government Awards.
Throughout all the period of using drilling rigs, scientists from the Saint-Petersburg university monitored the technical condition of the units and worked on innovations in this area. During the first twenty years, until 1990, they drilled four wells of different depths. All of the wells were over 1,500 meters deep.
Simultaneously with obtaining the core sample, the drilling technology itself and engineering solutions were being worked out. In 1990, a well (called the 5th Deep) drilling was started. This eventually led scientists to Lake Vostok. It was drilled without any information that there was a subglacial lake. No one else knew about this lake at that time and did not assume. The lake was discovered in 1994. At that time, the depth of the well was 3053 meters. The 5th Deep provided the most direct way to study the water body and the sediment layer. Subsequent years of research and seismological measurements have shown that Lake Vostok has huge dimensions. The length of the lake is about 250 km, the width is about 50 km, the depth is up to 750 m, the area is almost 20,000 km2. Lake Vostok is the largest subglacial lake in Antarctica.
This nonfreezing lake is covered from direct exposure to the sun, winds, and living organisms on the surface. According to some estimates, the lake has been isolated for about 14 million years. As the results of a thermal scanning of the surface show, the water temperature is very high at about 10-18oC, clearly indicating a subterranean heat source. In addition, above the surface of the water is a hundreds-of-meters high dome-shaped vault filled with air.
Lake Vostok is unique primarily because it has been isolated from the Earth’s surface for several millions of years. A four-kilometer-long ice shell above the lake served and still serves as a natural isolator. Scientists believe that living organisms can live in the lake’s waters, because it contains all the factors necessary for life.
In 1998, when the well was 3,623 meters deep, at the insistence of the International Antarctic Community, drilling operations were halted because there was then about 130 ± 20 meters of ice to the ice/water line, according to independent geophysical measurements. The Community requested that drilling operations be suspended until an environmentally clean technology was developed to penetrate this lake. Drilling operations were resumed only at the end of 2006, when such technology was created, and it took a very long time to settle it with the International Antarctic Community. Drilling to the surface of the lake lasted more than 5 years.
On 5 February 2012 Russian specialists were the first to penetrate the subglacial Antarctic water body, Lake Vostok. This event, at the drilling complex of the Russian Vostok Station, received a wide public and scientific resonance in Russia and abroad and was often compared to the achievements of pioneers in space exploration. Using a unique domestic technology developed at the Saint-Petersburg National Mineral Mining University, the deepest of all ice boreholes ever drilled on Earth was drilled into the 3769 m thick glacier, and water from the surface layer of the subglacial lake went up, as it had been predicted by the developers of environmentally clean penetration into Lake Vostok. During the summer 2012/13 season, drilling of a “fresh-frozen” ice core, formed from water that had risen up the borehole, began from a depth of 3,406 m. During the past two Antarctic seasons 2012/13 and 2013/14, the drilling team of the Russian Antarctic Expedition reached a depth of 3,724 m downhole. Thus, 45 m of the glacier remained to the ice/water line. These works were resumed in the 2014/15 season. In the morning, on 24 January 2015, drilling of the last meters of the glacier continued. By the end of the second 8-hour shift, two ice cores of 1 m and a bit each had been brought to the surface. On the morning of 25 January, drilling operations in the deep ice hole at Vostok Station continued. On this day, two drilling trips with obtaining the ice core were carried out. After the first trip the core with a length of 0.87 m was brought up to the surface and after the second one – 0.71 m. At the same time, in the second trip the ecologically clean penetration into the subglacial Lake Vostok was carried out again since 5 February 2012.
Conditions in the subglacial water body may be close to those on Earth during the Late Proterozoic (750-543 million years ago). Exploration of the lake could be useful in the study of Mars, as well as the moons of Jupiter and Saturn, where, according to some hypotheses, similar formations exist. This could be one of the most promising projects in the search for extraterrestrial life. Lake Vostok is a kind of time capsule, sealed about 14 million years ago. Its waters hold secrets not found anywhere else on the planet. Prehistoric microorganisms may still exist there to this day, capable of giving mankind new knowledge about the Earth’s biosphere, and possibly about life on other planets. All in all, it is an ideal laboratory to investigate evolution and explore the possibilities of the origin of life away from our planet.
The giant layer of ice that covers Lake Vostok is a kind of history textbook. It stores information about the state of our planet hundreds, thousands and even millions of years ago. The samples of this ice can be used to determine the amount of dust in the atmosphere, the level of gas impurities, the composition of water at a particular time. It is possible to study the concentration of greenhouse gas in the distant past and thus obtain accurate information not only about how the planet’s climate has changed, but also about what factors have caused these changes. And thus, to predict climate changes in the future.