ALBERT

Note: Erscheinungsjahr in Vorlageform:1996

Note: Table of contents Preface About the authors Acknowledgements Dedication List of figures List of tables List of symbols Part I Introduction and characteristics of permafrost I Definition and description 1.1 Introduction 1.2 Additional terms originating in Russia 1.3 History of permafrost research 1.4 Measurement of ground temperature 1.5 Conduction, convection and advection 1.6 Therm al regimes in regions based on heat conduction 1.7 Continentality index 1.8 Moisture movement in the active layer during freezing and thawing 1.9 Moisture conditions in permafrost ground 1.10 Results of freezing moisture 1.11 Strength of ice 1.12 Cryosols, gelisols, and leptosols 1.13 Fragipans 1.14 Salinity in permafrost regions 1.15 Organic matter 1.16 Micro-organisms in permafrost 1.16.1 Antarctic permafrost 1.16.2 High-latitude permafrost 1.16.3 High altitude permafrost in China 1.16.4 Phenotypic traits 1.16.5 Relation to climate change on the Tibetan plateau 1.17 Gas and gas hydrates 1.18 Thermokarst areas 1.19 Offshore permafrost 2 Cryogenic processes where temperatures dip below 0°C 2.1 Introduction 2.2 The nature of ice and water 2.3 Effects of oil pollution on freezing 2.4 Freezing and thawing of the active layer in permafrost in equilibrium with a stable climate 2.5 Relation of clay mineralogy to the average position of the permafrost table 2.6 Ground temperature envelopes in profiles affected by changes in mean annual ground surface temperature (MASGT) 2.7 Needle ice 2.8 Frost heaving 2.9 Densification and thaw settlement 2.10 Cryostratigraphy, cryostructures, cryotextures and cryofacies 2.11 Ground cracking 2.12 Dilation cracking 2.13 Frost susceptibility 2.14 Cryoturbation, gravity processes and injection structures 2.14.1 Cryoturbation 2.14.2 Upward injection of sediments from below 2.14.3 Load-casting 2.15 Upheaving of objects 2.16 Upturning of objects 2.17 Sorting 2.18 Weathering and frost comminution 2.19 Karst in areas with permafrost 2.20 Seawater density and salinity 3 Factors affecting permafrost distribution 3.1 Introduction 3.2 Climatic factors 3.2.1 Heat balance on the surface of the Earth and its effect on the climate 3.2.2 Relationship between air and ground temperatures 3.2.3 Thermal offset 3.2.4 Relation to air masses 3.2.5 Precipitation 3.2.6 Latitude and longitude 3.2.7 Topography and altitude 3.2.8 Cold air drainage 3.2.9 Buffering of temperatures against change in mountain ranges 3.3 Terrain factors 3.3.1 Vegetation 3.3.2 Hydrology 3.3.3 Lakes and water bodies 3.3.4 Nature of the soil and rock 3.3.5 Fire 3.3.6 Glaciers 3.3.7 The effects of Man 4 Permafrost distribution 4.1 Introduction 4.2 Zonation of permafrost 4.3 Permafrost mapping 4.4 Examples of mapping units used 4.5 Modeling permafrost distribution 4.6 Advances in geophysical methods 4.7 Causes of variability reducing the reliability of small-scale maps 4.8 Maps of permafrost-related properties based on field observations 4.8.1 Permafrost thickness 4.8.2 Maps of ice content 4.8.3 Water resources locked up in perennially frozen ground 4.8.4 Total carbon content 4.9 Use of remote sensing and airborne platforms in monitoring environmental conditions and disturbances 4.10 Sensitivity to climate change: Hazard zonation 4.11 Classification of permafrost stability based on mean annual ground temperature Part II Permafrost landforms II. 1 Introduction 5 Frost cracking, ice-wedges, sand, loess and rock tessellons 5.1 Introduction 5.2 Primary and secondary wedges 5.2.1 Primary wedges 5.2.1.1 Ice-wedges 5.2.1.2 Sand tessellons 5.2.1.3 Loess tessellons 5.2.1.4 Rock tessellons 5.2.2 Secondary wedges 5.2.2.1 Ice-wedge casts 5.2.2.2 Soil wedges 6 Massive ground ice in lowlands 6.1 Introduction 6.2 Distribution of massive icy beds in surface sediments 6.3 Sources of the sediments 6.4 Deglaciation of the Laurentide ice sheet 6.5 Methods used to determine the origin of the massive icy beds 6.6 Massive icy beds interpreted as being formed by cryosuction 6.7 Massive icy beds that may represent stagnant glacial ice 6.8 Other origins of massive icy beds 6.9 Ice complexes including yedoma deposits 6.10 Conditions for growth of thick ice-wedges 6.11 The mechanical condition of the growth of ice-wedges and its connection to the properties of the surrounding sediments 6.12 Buoyancy of ice-wedges 6.13 Summary of the ideas explaining yedoma evolution 6.14 Aufeis 6.15 Perennial ice caves 6.16 Types of ice found in perennial ice caves 6.17 Processes involved in the formation of perennial ice caves 6.18 Cycles of perennial cave evolution 6.18.1 Perennial ice caves in deep hollows 6.18.2 Sloping caves with two entrances 6.18.3 Perennial ice caves with only one main entrance but air entering through cracks and joints in the bedrock walls 6.18.4 Perennial ice caves with only one main entrance and no other sources of cooling 6.19 Ice caves in subtropical climates 6.20 Massive blocks of ice in bedrock or soil 7 Permafrost mounds 7.1 Introduction 7.2 Mounds over 2.5 m diameter 7.2.1 Mounds formed predominantly of injection ice 7.2.1.1 Pingo mounds 7.2.1.2 Hydrostatic or closed system pingos 7.2.1.3 Hydraulic or open system pingos 7.2.1.4 Pingo plateaus 7.2.1.5 Seasonal frost mounds 7.2.1.6 Icing blisters 7.2.1.7 Perennial mounds of uncertain origin 7.2.1.8 Similar mounds that can be confused with injection phenomena 7.2.2 Mounds formed dominantly by cryosuction 7.2.2.1 Paisas 7.2.2.1.1 Paisas in maritime climates 7.2.2.1.2 Paisas in cold, continental climates 7.2.2.1.3 Lithalsas 7.2.2.1.4 Palsa/Lithalsa look-alikes 7.2.3 Mounds formed by the accumulation of ice in the thawing fringe: Peat plateaus 7.3 Cryogenic mounds less than 2.5 m in diameter 7.3.1 Oscillating hummocks 7.3.2 Thufurs 7.3.3 Silt-cycling hummocks 7.3.4 Niveo-aeolian hummocks 7.3.5 Similar-looking mounds of uncertain origin 7.3.6 String bogs 7.3.7 Pounus 8 Mass wasting of fine-grained materials in cold climates 8.1 Introduction 8.2 Classification of mass wasting 8.3 Slow flows 8.3.1 Cryogenic creep 8.3.1.1 Needle ice creep 8.3.1.2 Frost heave and frost creep 8.3.1.3 Gelifluction 8.3.1.4 Other creep-type contributions to downslope movement of soil 8.3.2 Landforms produced by cryogenic slow flows in humid areas 8.3.3 Landforms developed by cryogenic flows in more arid regions 8.4 Cryogenic fast flows 8.4.1 Cryogenic debris flows 8.4.2 Cryogenic slides and slumps 8.4.3 Cryogenic composite slope failures 8.4.3.1 Active-layer detachment slides 8.4.3.2 Retrogressive thaw failures 8.4.3.3 Snow avalanches and slushflows 8.4.3.3.1 Snow avalanches 8.4.3.3.2 Slush avalanches 8.5 Relative effect in moving debris downslope in the mountains 9 Landforms consisting of blocky materials in cold climates 9.1 Introduction 9.2 Source of the blocks 9.3 Influence of rock type 9.4 Weathering products 9.5 Biogenic weathering 9.6 Fate of the soluble salts produced by chemical and biogenic weathering 9.7 Rate of cliff retreat 9.8 Landforms resulting from the accumulation of predominantly blocky materials in cryogenic climates 9.8.1 Cryogenic block fields 9.8.1.1 Measurement of rates of release of blocks on slopes 9.8.2 Cryogenic block slopes and fans 9.8.3 Classification of cryogenic talus slopes 9.8.3.1 Coarse blocky talus slopes 9.8.4 Protection of infrastructure from falling rock 9.9 Talus containing significant amounts of finer material 9.9.1 Rock glaciers 9.9.1.1 Sedimentary composition and structure of active rock glaciers 9.9.1.2 Origin of the ice in active rock glaciers 9.9.1.3 Relationship to vegetation 9.9.2 Movement of active rock glaciers 9.9.2.1 Horizontal movement 9.9.2.2 Movement of the front 9.9.3 Distribution of active rock glaciers 9.9.4 Inactive and fossil rock glaciers 9.9.5 Streams flowing from under rock glaciers 9.10 Cryogenic block streams 9.10.1 Characteristics 9.10.2 Classification 9.10.2.1