Permafrost

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variations in different parts. Keywords: Xing’anling Mountains, SLP, permafrost degradation, climatic warming, deforestation Main Features of Soil Seasonal Thawing and Freezing in the Timan-Pechora Oil-and-Gas Province I. Shamanova (Production and Research Institute for Engineering Survey in Construction, PNIIIS) Abstract: Soil seasonal thawing and freezing is the most important parameter used to assess the engineering geocryological conditions of developed territories. Seasonally thawing (STL) and freezing (SFL) layers regulate thermal and mass exchange between the perennially frozen ground (PFG) and the atmosphere. The large-scale engineering geocryological survey, performed by PNIIIS in the Timan-Pechora oil-and-gas province in 2000-2004, made it possible to characterize in detail STL and SFL under different landscape conditions, to estimate the effect of the zonal and regional factors of the natural environment on the processes of soil thawing and freezing, to predict technogenic changes in the STL and SFL thickness and temperature, and to estimate the permissible technogenic load (which does not initiate cryogenic hazards) during different types of industrial development of the territory. The specific features of soil seasonal thawing and freezing are as follows. (1) STL is predominant in tundra and is local in forest-tundra (is confined only to peat bogs and mounds). SFL occupies about 20% of the tundra zone and is confined to the areas with deep PFG and thawed zones. In forest-tundra SFL is predominant (occupies up to 90% of the area). (2) The depth of soil seasonal thawing and freezing varies from 0.3 to 3.0 m. The most typical STL thickness is 0.8-1.8 m in tundra and 1.0-2.2 m in forest-tundra; the SFL typical thickness is 1.0-2.0 m. (3) Transient (tav.s. varies from 0 to ± 1°С) and semitransient (tav.s. varies from ± 1 to ± 2°С) types of soil seasonal thawing and freezing are observed in the most part of the territory, which characterizes the natural environment as very dynamic. The technogenic impact can principally change the STL and SFL thickness and temperature, which provokes development of cryogenic hazards that cause deformations of engineering structures and irreversible changes in the ecosystems. Therefore, it is necessary to take complex engineering protection measures on developed territories. Key words: Seasonal thawing, freezing, technogenic impact. 173
174 Permafrost Terrain Analysis along the Tommot-Yakutsk Railway I.S. Vasiliev, S.P. Varlamov, A.N. Fedorov, M.N. Zheleznyak (Melnikov Permafrost Institute SB RAS, Yakutsk, Russia) Abstract: The Tommot-Yakutsk Railway now under construction is 454 km long and passes through the area between latitude 59° and 62°N and longitude 127° and 130°E. Elevations range from 100 to 600 m a.s.l. The railway route traverses the terrain with extremely difficult geocryological conditions. The difficulty is related to the development of adverse processes and phenomena, especially those associated with frost action. Their distribution, in combination with environmental factors, is differentiated into seven physiographic regions. 1. The Lena stepped outcrop, dolomite region is characterized by distinctly stepped relief and by discontinuous occurrence of permafrost. The high amounts of solar radiation and precipitation in the most southerly region determine the occurrence of unfrozen ground on elevated well-drained interfluves and warm slopes. Permafrost up to 30 m thick occurs on the shadowed north-facing slopes, and on the lower slopes and bottoms of small valleys (Figure). The northern limit of unfrozen ground is indicated by the range of cedar pine and mixed forest of pine, larch, aspen, birch and occasional cedar pine with undergrowth of mountain-ash. Ground temperatures (Тg) vary from +1.0 to –2.0°C, depths of seasonal freezing (ξfr) are 2.0 to 3.5 m, and depths of seasonal thawing (ξth) range from 0.8 to 2.5 m. The railway route passes along the foot of slopes and crosses the bottoms of small valleys, where surface disturbance would trigger solifluction, movement of rock fields, frost heaving and thaw settlement. 2. The Lena-Aldan rolling watershed, dolomite region is also characterized by dissected relief, but permafrost with thicknesses of 50 m in the south to 650 m in the north is continuous. Тg varies from +0.5 to –3.5°С, ξfr from 2.3 to 3.5 m and ξth from 1.2 to 3.0 m. Shallow taliks are encountered locally on interfluves, warm slopes, burns and forest cuts. Because of the dominance of surficial clayey silts on the slopes, percolation of suprapermafrost water is impeded resulting in downslope flow. This leads to accumulation and ponding of suprapermafrost water on the footslopes and small valley bottoms, causing peat accumulation, heaving and ice saturation in proluvial-alluvial deposits that are crossed by the railway route. Surface disturbance will inevitably result in solifluction, mud flows, slumping, thaw subsidence, and sheet and rill wash. 3. The Lena-Amga rolling, karsted limestone region has less dissected relief and continuous permafrost with an estimated thickness of 650 to 720 m. Тg varies from +0.5 to –3.5°, ξfr is 2.5 to 3.2 m and ξth is 0.8 to 2.5 m. Both surface and subsurface karst is developed throughout the region. Surface disturbance in the areas crossed by the railway route causes slumping, mud flows, solifluction, thaw subsidence, frost heaving, and sheet and rill wash. 4. The Lena-Aldan undulating, sandstone region has continuous permafrost with an estimated thickness of 400 to 620 m, Тg of +0.2 to –4.0°С and ξth of 0.7 to 2.3 m. The region is a slightly dissected plateau of the Jurassic mantle of planation blanketed by polygenetic clayey silts which contain ice wedges in the north and highly kaolinized silty sands derived from sandstones in the south. Shallow infiltration-radiation taliks are encountered on formerly burned areas on the interfluves. Poor surface drainage keeps them wet due to infiltration of precipitation. Solifluction, thermokarst, slope and valley karst are widespread in the region. In
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SEE AUTHOR INDEX AND REVISED PROGRA
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G.М. Dolgih, Dolgih D.G., Okunev S
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Rev I. Gavriliev The thermal conduc
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Xiao-zu Xu,Bin-xiang Sun,Qi Liu,Shu
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Lopez CML, Katamura F, Argunov R, F
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Grebenets V., Kraev G. Nagornov D.
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V.A. Istratov, A. Kuchmin, A.D. Fro
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Mamoru Ishikawa Mountain permafrost
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ORGANIZING COMMITTEE Co-Chairs Acad
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CO-SPONSORS Chinese Academy of Scie
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curve of the accumulated displaceme
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zone of Tien Shan. Key words: Compl
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negotiations currently under way am
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distribution according to the seaso
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number of freeze-thaw cycles. With
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The Technique of Geoinformation Mod
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Monitoring Study on the Boundary Th
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The Calculation and Control Methods
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observations are presented. Key wor
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frost heave is one typical case of
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whose total water content and poros
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effectively and restrain subgrade d
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Peninsula, Pur and Tar interfluve,
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1-D Numerical Analysis to Predict a
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of the two simulation-analysis meth
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frozen soil. While compared with th
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The maximum vertical deformations a
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dangerous pollutants, including hea
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fact of the rising of artificial pe
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The Thermal Conductivity of Segrega
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discussed in view of geotechnical a
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Numerical modeLling of thawing rail
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experiment for obtaining those para
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lake and in purpose to protect surr
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The Concept of an Engineering-geocr
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Effect of seismic events on the sta
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Electrical Conductivity of Rocks in
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mechanics parameters both in frozen
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influence its temperature change pr
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Experimental and numerical simulati
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signifies that the diffusion action
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Experimental Study on the Influence
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does not spread the energy in the f
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and seismic response of infrastruct
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Cooling effect of crushed rock reve
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The analysis of the data concerning
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the extended duration of freezing p
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Distribution of Rock Glaciers in th
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Methods of Theoretical and Experime
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properties, and is able to move bot
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especially water flooding, could be
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mechanisms during the compression a
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inundations and catastrophic breako
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of quantity of neglected interactio
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Past and present salinization in na
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Temperature Regime of Atmosphere an
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disturbance: conflicting, critical
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Application of ERS InSAR for detect
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critical to melt-water irrigation i
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Features of hydrothermal conditions
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associated with the southwest summe
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Significance of Microtopography and
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Reconstruction of paleocryogenic st
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Dendroclimatic investigations of fo
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anthropogenic disturbance. Despite
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and +38°C in summer. Continuous pe
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Page 138 and 139: can lead to a global ecological cat
Page 140 and 141: Assessment of Frozen Soils Environm
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Page 144 and 145: Cryospheric changes in the West Sib
Page 146 and 147: Response of Ice-rich Permafrost to
Page 148 and 149: About Role of Thermokarst in Global
Page 150 and 151: presence may be debated since there
Page 152 and 153: territories have natural and anthro
Page 154 and 155: will contribute to the resolution o
Page 156 and 157: Impact of Frozen Ground Change on S
Page 158 and 159: Antarctica. Key words: Cape Hallett
Page 160 and 161: The sensitivity of Tibetan Plateau
Page 162 and 163: infrapermafrost waters that are dis
Page 164 and 165: Keywords: cryosphere, anthropogenic
Page 166 and 167: Key words: Alaska, oil exploration,
Page 168 and 169: Possible Change of Runoff in the Up
Page 170 and 171: Theme 5. Monitoring, mapping and mo
Page 172 and 173: Mathematical model for quantitative
Page 174 and 175: heat transfer model with phase chan
Page 176 and 177: e.s.l.). In 2005 this mine was equi
Page 178 and 179: Surface- coupled 3-D Permafrost Mod
Page 180 and 181: • the territories where the perma
Page 182 and 183: associated soil surface temperature
Page 186 and 187: disturbed landscapes, thaw subsiden
Page 188 and 189: ⎛ ⎜ 1 ⎛ ⎞ ⎜ ε σ = Eε e
Page 190 and 191: Mountain permafrost study in the Ru
Page 192 and 193: Permafrost Distribution and Thickne
Page 194 and 195: Permafrost Distribution and Thickne
Page 196 and 197: studies (Natsagdorj et al. 2000), t
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Page 200 and 201: models were run using standardized
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Page 208 and 209: In high mountain regions, as well a
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Page 214 and 215: Monitoring of the snow cover in the
Page 216 and 217: deterministic model combined with p
Page 218 and 219: We have the map of seasonally froze
Page 220 and 221: approximately with the -5°C mean a
Page 222 and 223: Theme 6. Others Developing an Onlin
Page 224 and 225: The FGDC identifies, archives, docu
Page 226 and 227: Final Revised Program (August 28, 2
Page 228 and 229: Professor Dr. Lin Zhao, CAREERI, CA
Page 230 and 231: Monday, Aug 7, 2006 Location: Ningw
Page 232 and 233: Bending properties monitored in ful
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Theme 1-3: Engineering: Frozen grou
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Chairs: Bernhard Diekman, Ron Slett
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Theme 5-3: Mapping: Permafrost and
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Experimental research on thermal co
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A Preliminary Permafrost and Ground
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Bulley H----------94 Caffee M W ---
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Guo Jian-wen -------177 Guo Jian-We
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Kudryavtsev S -------53 Kulish E M
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Nefedieva Yu A ----------------87 N
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Stauch G -------89 Streletskaya I.
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Zhang Jian-min --------25 Zhang Jin
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Permafrost

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