Inland waters are not only accumulations of liquid, but also solid moisture. Solid water forms mountain, cover and underground glaciation. The area of the underground ice accumulation was called cryolithozone in 1955 by Shvetsov, a Soviet permafrost specialist. This area has a more common name - permafrost.
Cryolithozone is the upper layer of the cortex. Rocks at this level are characterized by lower temperatures. This layer includes permafrost, rocks, as well as non-freezing horizons of highly mineralized groundwater.
During long harsh winters with a relatively small thickness of cover there is a significant heat loss in the rocks. In this regard, there is freezing to a considerable depth. As a result, solid masses of water are formed. In the summer, permafrost does not have time to thaw completely. Soil maintains a negative temperature, thus, at a considerable depth and for hundreds and even thousands of years. The permafrost of Russia is also forming under the additional influence of huge reserves of cold. They accumulate in areas with lower average annual temperatures.
For a long time, rocks at low temperatures are “cemented” in some way by moisture. Permafrost includes underground ices, moisture accumulations form wedges, lenses, streaks, layers of ice. Permafrost may contain different amounts of ice. The indicator of "ice" can vary from 1-3 to 90%. As a rule, ice occurs in mountainous areas. At the same time, permafrost in the lowland areas is characterized by increased ice content.
Cryolithozone is a unique phenomenon. Permafrost interested explorers in the 17th century. At the beginning of the 18th century, Tatishchev mentioned this phenomenon in his writings, and Middendorf conducted the first research in the mid-19th century. The latter measured the temperature of the layer in several areas, established its thickness in the northern regions and suggested the origin and factors of a fairly wide distribution of permafrost zones. In the second half of the 19th and early 20th centuries, serious research began in conjunction with the prospecting work of mining engineers and geologists.
In Russia, the permafrost zone is spread over an area of about eleven million square kilometers. This is about sixty-five percent of the entire territory of the state.
Permafrost from the south is limited to the Kola Peninsula. From its central part, it stretches across the East European Plain near the Arctic Circle. Then, along the Urals, there is a deviation to the south almost to the sixtieth degree of north latitude. Along the Ob, permafrost stretches to the mouth of Severnaya Sosva, after which it passes along the Siberian Uvaly (southern slopes) to the Yenisei in the region of the Podkamennaya Tunguska. At this point, the border turns quite steeply to the south, runs along the Yenisei, then goes along the slopes of Altai, Tuva, Western Sayan to the border with Kazakhstan.
