The types and formation of taliks in the permafrost zone

Even in the most severe climatic conditions the spatial distribution of permafrost is not universally continuous. Within the permafrost zone the frozen ground can be absent within many sections of river valleys and watersheds, on south-facing slopes, under lakes, at sites of concentrated discharge of groundwater or of its recharge by seepage, volcanic craters, calderas, under some of the present glaciers and above the interior-Earth thermal anomalies associated with oxidation reactions, etc....

Characteristics of organic mineral and chemical composition of frozen earth materials

The organic-mineral and chemical composition of frozen materials and their granulometry have not been well studied to the present time. Much attention was earlier given to the study of ice (as a mineral and a rock) as a component of big accumulations and deposits. However, seasonal and perennial freeze-thaw bring about not only transformations of ice, but also changes in mineral, chemical and organic composition of the mineral matrix. Chemical processes that occur in the regions of development...

Dependence of the permafrost thickness and temperature regime on geological factors and processes

The effect of geological factors and processes on the permafrost thickness and temperature regime is essentially corrected by a heat balance of the upper layers of the lithosphere. This correction can take place as a result of the anisotropy of heat transfer conditions in rock which is dependent on the specific features of their composition, properties and structure, as well as on the redistribution of heat fluxes because of the occurrence of additional heat sources such as active zones of...

History of research of the zone of permafrost and the frozen materials composing this zone

We can recognize several stages in the history of research into seasonally and perennially frozen ground. The first stage (from the sixteenth century to the first half of eighteenth century) is that of the first information concerning discoveries of the permafrost and the first attempts to explain the reasons for its existence. There is no doubt, though, that natives of the northern regions and Siberia always knew of its existence. The first data on permafrost (which was termed the 'Russian...

Development of migrationalsegregated ice interlayers

The particular features of thermal-physical, physical-mechanical and physico-chemical processes in freezing ground create conditions for the formation of migrational-segregated ice layers with various orientation, frequency and thickness in other words, they cause the appearance and development of cryogenic structures. These processes in freezing ground essentially transform the structure, density and strength of soils. For example, as a result of dehydration of the unfrozen part of the ground...

Normative documents for engineering design and construction in the permafrost regions

Engineering geological surveys, design work and construction are carried out in conformity with documented norms. In accordance with the System of Norms for Construction adopted by the USSR State Construction Committee in 1983, they are subdivided into Ail-Union, department and republic normative documents. The Ail-Union normative documents are obligatory for all enterprises, organizations and amalgamations subordinate to the Ail-Union, departmental and republic bodies, carrying out work in a...

Classification of processes and phenomena

Exogenous geological processes and phenomena in the permafrost regions are often referred to as cryogenic (frozen ground) geological processes and phenomena. They are due to the development of the thermal-physical, physico-chemical and mechanical processes that occur in freezing, frozen and thawing soils, which were considered in the previous chapters. The specific features of exogenous geological processes in the permafrost zone are determined by the cyclic recurrence of freezing and thawing,...

Late Cenozoic

The evolution of natural conditions in the Late Cenozoic caused by global cooling of the Earth's climate led to the formation of the permafrost in the north, north-east and within high-elevation mountain systems on the south of the former USSR which continues to the present day. The history of the cryogenic development of the north-eastern part of Eurasia in the Late Cenozoic recorded in stratigraphy has not been studied uniformly and adequately as a whole. The initial period of the study of...

Interaction of groundwater with the permafrost and types of cryohydrogeological structures

Permafrost affects the groundwater condition through the mechanism of mutual interaction. The water loses energy to the frozen rock, tending to thaw it, while the frozen rock, on the contrary, tends to freeze the water by taking its heat energy. The permafrost zone currently existing is derived from this complex process proceeding in various directions. Partial or full freezing of water-bearing horizons, complexes, and zones of jointing has occurred as a result of such interaction. They have...

Frozen rocks as naturalhistorical geological formations

A few periods of active formation and existence of frozen ground alternating with periods of its disappearance or sharp decrease in extent can be discerned in the history of this planet's development. The distribution of frozen ground over the Globe in ancient epochs is associated with regions where ancient continental glaciations occurred and their moraine deposits are found. Therefore during the first half of the Earth's geological history (2.5 billion years ago) permafrost is unlikely to...

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Fig. 3.5. (a) Development of heaving stresses Phea and (b) heaving hea of the surface (isurf -2 C) of soil samples, depending on depth of freezing 1-3 - clay (1 - kaolinite, 2 - polymineral, 3 - montmorillonite) 4 - peat, 5 - sandy silty material 6 - sand). point over the value at another point, as a percentage of the distance between them. In natural conditions, the values of this coefficient of irregularity of heaving may vary within the range 3-15 , while the change in absolute values of...

Physical properties of the frozen materials

Moisture content, ice content, density and porosity are the main physical indices that characterize the engineering-geological aspects of frozen and thawed soils. Moisture content of frozen soil is the water content, based on drying at a temperature of 100-105 C to obtain the constant mass of solid material. There are different indices - total moisture content, integral (natural) moisture content and volumetric moisture content. Total moisture content Wtot of the frozen soil is the ratio of...

Geologicgenetic types of sedimentary materials in the permafrost regions

Owing to the specific conditions and factors of lithogenetic processes in the permafrost regions there are a number of distinctive features in the composition, structure and properties of the frozen soils with development of essentially new genetic types of sedimentary formations, found only in the areas of permafrost development. A number of terms appeared in the literature, on the one hand specifying the genesis of sedimentary formations in the permafrost regions, such as 'cryogenic eluvium',...

Development

Kudryavtsev (18) geocryological forecast refers to the scientific prediction of changes of geocryological conditions which will occur in the future, either in the context of natural circumstances or in the course of economic development. In line with this definition two types of forecast, the evolutional (often designated natural-historical) and the technological are distinguished. The first includes forecasting the changes in permafrost characteristics and of the processes...

Regionalization in geocryological mapping

Geocryological maps are compiled to study geocryological conditions in two cases at the stage of completion of a geocryological survey at any scale, and when summarizing the geocryological and other materials at the general scales (without conducting the geocryological surveys). The procedure of compilation of geocryological maps at surveying scales is based on the integrated study of two groups of cryoforming factors and conditions 1) zonal landscape-climatic and 2) regional...

Distribution of permafrost and spatial variations of its mean annual temperature

The great extent of the territories of the former USSR from west to east and from north to south, the complexity of orographic, geological, tectonic and hydrogeological structures, of landscape and of climate, together with the changes in the late Cenozoic, are responsible for the variety of geocryological conditions in their different parts. The zonal distribution of permafrost in the territory of the former USSR is associated with two main circumstances 1) the history of the cryogenic...

Moisture exchange properties of soils

Analysis of the state of moisture in the soil and its capacity to move is the first priority in the assessment of mass-exchange characteristics of hydraulic conductivity, mass capacity, coefficient of diffusion and moisture potential. It was shown by experiment that with higher moisture content the values of ground water potential and differential water capacity increased. Low absolute values of the chemical potential of the moisture of high moisture content materials indicate small amounts of...

External load

In frozen soils under the effect of external loads, mechanical stresses developed by means of interrelated and successive processes are elastic deformations (conventional-momentary and elastic aftereffect), plastic deformation (attenuating creep, viscous flow, unattenuating creep or progressive flow) and destruction (brittle, when the body loses its continuity, or plastic with loss of soil stability). In these processes the frozen soils show rheological properties, caused by their...

Microstructure of frozen soils

The microstructure of frozen soils implies the totality of microstructural and microtextural features inherited from the unfrozen materials as well as those acquired during freezing and in the frozen state. The concept of microstructure includes the size, shape, pattern of surface and the quantitative proportions of elements that compose the frozen soil and the nature of their relationships. Microstructure is defined as the totality of attributes that characterize the relative arrangement and...

The economic development of the permafrost regions

The intense pace of economic development of the territories within the permafrost region continues to increase steadily. Under the effect of different types of development all or some of the components of the natural environment, including the geocryological conditions, can change, resulting in transformations of the natural complex as a whole. 'The geological environment' is defined as an essential constituent of the natural environment. We address it in several aspects as far as various types...

Ljii I I Ii I I Ii

Tentative character of the change in the maximum thickness of (1) syncryogenic and (2) epicryogenic sedimentary layers in the development of the Earth's lithogenesis. adjacent territories (on account of cold and dry glacier winds). Thus, large ice covers have as a rule rather wide adjacent periglacial zones within which the low temperature permafrost exists. At the same time the permafrost can be lacking under ice covers of great thickness because of the pressure of the ice mass or...

Frost heaving of soils

Frost heaving of soils arises due to the increase in volume of freezing moisture and the accumulation of ice (owing to water migration) at freezing. This process is widely developed both in the permafrost regions and in the regions of deep seasonal freezing of ground. The largest deformations due to heaving are observed in the freezing of an open system of highly permeable, usually sand-silty soils and saturated silty-sandy-clays at low rates of freezing and in the proximity of ground water...

Types of seasonal freezing and thawing of the ground

As early as the first years of the 1950s, V.A. Kudryavtsev pointed out that the processes of freezing and thawing are, on one hand, thermal-physical resulting from thermal interaction of the atmosphere and surrounding space with the lithosphere, and on the other geological-geographical, since the thermal processes take place in the particular geological medium and a complicated geographical setting. It was convincingly proved that determination of the features of seasonal freezing and thawing...

Textural characteristics of the frozen material

Cryogenic texture of the frozen material is assumed to be that of the ice framework, consisting of inclusions, intercalations differing in shape and size, orientation and spatial arrangement, by which the structure of the Fig. 7.9. Curves of differential distribution of void volumes by radius (a) and dependence of unfrozen water content on temperature in siliceous (& ), sandy (c) and clay-rich (d) soils and rocks 1 - diatomitic clay 2 - diatomite 3 - tripoli 4 - opoka 5 - silica gel 6-8 -...

Slope processes and phenomena

Slope processes and phenomena are caused by the action of gravity forces and lead to a variety of deformations - collapse, talus, landsliding, solifluction, stone streams, rapid flows and the like. The most distinct manifestation of gravitational forces occurs on steep slopes, with failure and displacement of rock waste and stone blocks resulting from the weathering processes. The rate of material displacement can vary, being high on certain sites. The history of the sedimentary material within...

Structure problems and scientific themes of geocryology

At the present time further accelerated development and differentiation of permafrost science is taking place. A number of scientific directions in geocryology have pretensions to being independent scientific disciplines (cryolithology, engineering geocryology, etc.). However, as is obvious from the foregoing, geocryology has to investigate practically all the aspects of formation and development of the ground in the qualitatively new (frozen) state. Therefore it is natural that the structure...

Formation of sedimentary materials in the permafrost regions cryolithogenesis

The most general and fundamental geological principles of the formation of sedimentary deposits in the permafrost regions are associated with the questions of grain-size distribution and chemical-mineral composition, structural-textural features and composition of the frozen sediments, the nature of which is elucidated in the course of study of chemical, physical-chemical and physico-mechanical processes that occur in the sediments of the permafrost regions in their stage-by-stage...

Formation of structure in freezing and thawing soils

The wide spectrum of physico-chemical and physical-mechanical processes which accompany freezing and thawing of soils causes considerable structural transformations of their organic-mineral skeleton manifested by change in the size, shape, relations and orientation of structural elements (primary particles, mineral and organic-mineral aggregates). The size of structural elements can increase or decrease during freezing. The decrease is a result of dispersion effects and the increase is caused...

Basic types of cryogenic structures

To explain reliably the particular features of generation and growth of different types of superimposed and inherited cryogenic structures (Table 4.1) we should know the mechanism and pattern of formation of the vertical and horizontal ice layers in soil during freezing (thawing). Superimposed cryogenic structures normally appear in soils which are relatively homogeneous (prior to freezing), as a result of the freezing process and not as a result of the primary (initial) structure of the...

Groundwater of the permafrost regions

In response to repeated changes in the climatic conditions through the Pleistocene and Holocene, which included glaciations and general cooling, fundamental cryogenic transformations occurred within the upper part of the lithosphere. They extended over vast portions (as far as area and depth are concerned) of the Earth's crust, creating quite a specific hydro-geological situation. Groundwater survived only in taliks of various types, below the permafrost base, within the zones of supra- and...

Structure of the permafrost and spatial variability of its thickness

The permafrost is defined as the part of the Earth's crust in which the earth materials have negative temperature, regardless of the presence or phase composition of water in it. The structure of the permafrost, its thickness and distribution reflect the combined result of the whole history of its formation and the dynamics of perennial ground freezing from the end of the Neogene up to the present time. The permafrost thickness within the territory of the former USSR varies greatly, from the...

Notes on translations and definitions

In transliterations, the system used by the Scott Polar Research Institute's bibliographic services has been followed. The following dictionaries, glossaries and similar items have been used Challinor's Dictionary of Geology, 6th edn (Ed. Wyatt). 1986. University of Wales Press, Cardiff. 374 pp. Slovar' Sokrashcheniy Russkogo Yazyka, 1977 Dictionary of Abbreviations of the Russian Language . Elsevier's Dictionary of Earth Sciences Russian-English (compilers K.P. Bhatnagar amd S.K. Battacharya)...

Methods of amelioration of frozen ground for foundations

By amelioration (improvement) is meant a purposeful change of mean annual temperature, structure and properties of frozen, freezing and thawing ground and of the thermal-moisture regime in the direction required for solving the particular practical problems. Thermal, water-thermal, mechanical, physical-chemical and chemical amelioration is used. Thermal amelioration consists of the artificial lowering or raising of ground temperature using various heat sources. Heat transfer is performed in...

Principles of construction on permafrost bases and foundations

Frozen Footings

For construction outside the permafrost regions it is usually believed that all the load from a structure is transmitted through the base of the foundation to bearing ground while ground in contact with the sides of a foundation only occasionally carries a vertical load (as with piles and deep foundations). The interaction between foundations and ground is assessed differently in the regions of deep seasonal freezing and of permafrost. The load is transmitted to ground here through all the...

Natural ice as a monomineral rock

All kinds of natural ice that form independent bodies and accumulations can be regarded as a monomineral rock. They develop under condi tions of negative temperature of land and sea surface, atmosphere and lithosphere. Distribution of ice on the Earth's surface and in the crust is extremely nonuniform. Major masses of ice are concentrated on the land surface, mainly as glaciers and ice sheets. With an areal extent of only 3.1 (in relation to the Earth's surface) they constitute over 97 of all...

Frost cracking Assuring and polygonal formations surface and underground

Ground Cracking Under Dry Conditions

Frost cracking represents the process of temperature strain of frozen rocks in the variable temperature gradient fields. The volumetric tensions arising due to changes in temperature of ground within the annual range of temperature variations can lead to frost cracking of soil masses. Cracking takes place on the surface and penetrates the ground forming polygons in plan (Fig. 5.4). Multiple repetition of the frost cracking process gives rise to cryogenic formations and specific features of the...

Water transfer and ice formation in freezing and thawing soils

There are basically two different ways that soils freeze with and without water migration. Soil freezing without water migration occurs either in the case of soils of low moisture content or a sufficiently rapid advance of the freezing boundary. For example, when a soil sample is frozen through quickly at temperatures of 60 C, 70 C, water freezes in situ, since the temperature field is by a factor of 10 more active than the moisture content field. Usually freezing in nature proceeds slowly...

Of construction

Economic development is always integrated and multifarious and includes construction and operation 1) of civil and industrial installations (residential, social, municipal, factory buildings and structures) 2) of linear structures (railroads and highways, pipelines, underground lines, power lines 3) of airfields 4) of hydrotechnical structures. The special features of construction and operation of buildings within the permafrost regions will be discussed in the next chapter. This chapter is...

Chemical reactions and processes in freezing and thawing soils

Essentially the same chemical reactions take place in soils during freezing and thawing and in the frozen state as in unfrozen materials. These reactions are solution, hydration, substitution, oxidation-reduction, ion exchange etc., but in the cold regions they have a number of specific features. For example, solution is less intense because under lower temperatures some salts dissolve at a much slower rate. Apparently, because of low temperatures the permafrost regions contain considerable...