Permafrost Monthly Alerts (PMAs)

12062959 Kaufman, Darrell S. (Northern Arizona University, School of Earth Sciences and Environmental Sustainability, Flagstaff, AZ); Jensen, Britta J. L.; Reyes, Alberto V.; Schiff, Caleb J.; Froese, Duane G. and Pearce, Nicholas J. G. Late Quaternary tephrostratigraphy, Ahklun Mountains, SW Alaska: JQS. Journal of Quaternary Science, 27(4), p. 344-359, illus. incl. 6 tables, strat. col., sketch map, 33 ref., May 2012. Supplemental information/data is available in the online version of this article.

Radiocarbon-dated sediment cores from six lakes in the Ahklun Mountains, south-western Alaska, were used to interpolate the ages of late Quaternary tephra beds ranging in age from 25.4 to 0.4 ka. The lakes are located downwind of the Aleutian Arc and Alaska Peninsula volcanoes in the northern Bristol Bay area between 159° and 161°W at around 60°N. Sedimentation-rate age models for each lake were based on a published spline-fit procedure that uses Monte Carlo simulation to determine age model uncertainty. In all, 62 ¹⁴C ages were used to construct the six age models, including 23 ages presented here for the first time. The age model from Lone Spruce Pond is based on 18 ages, and is currently the best-resolved Holocene age model available from the region, with an average 2s age uncertainty of about ± 109 years over the past 14.5 ka. The sedimentary sequence from Lone Spruce Pond contains seven tephra beds, more than previously found in any other lake in the area. Of the 26 radiocarbon-dated tephra beds at the six lakes and from a soil pit, seven are correlated between two or more sites based on their ages. The major-element geochemistry of glass shards from most of these tephra beds supports the age-based correlations. The remaining tephra beds appear to be present at only one site based on their unique geochemistry or age. The 5.8 ka tephra is similar to the widespread Aniakchak tephra [3.7 ± 0.2 (1s) ka], but can be distinguished conclusively based on its trace-element geochemistry. The 3.1 and 0.4 ka tephras have glass major- and trace-element geochemical compositions indistinguishable from prominent Aniakchak tephra, and might represent redeposited beds. Only two tephra beds are found in all lakes: the Aniakchak tephra (3.7 ± 0.2 ka) and Tephra B (6.1 ± 0.3 ka). The tephra beds can be used as chronostratigraphic markers for other sedimentary sequences in the region, including cores from Cascade and Sunday Lakes, which were previously undated and were analyzed in this study to correlate with the new regional tephrostratigraphy. Abstract Copyright (2010), John Wiley & Sons, Ltd.

DOI: 10.1002/jqs.1552

12061486 Nyberg, Maria E. (Abo Akademi University, Department of Geology and Mineralogy, Turku, Finland); Osterholm, Peter and Nystrand, Miriam I. Impact of acid sulfate soils on the geochemistry of rivers in south-western Finland: Environmental Earth Sciences, 66(1), p. 157-168, illus. incl. 4 tables, sketch map, 38 ref., May 2012.

Large areas of acid sulfate (AS) soils are located along the coastal plains of Finland, and previous studies have shown that after reclamation they release extreme quantities of metals to watercourses in mid-western and northern Finland. In this study on streams of south-western Finland, where little information about AS soils is available, these soils were found to exhibit the same pattern of elevated metal- and sulfate concentrations as in the notorious AS soil landscapes of mid-western Finland. Meteorologically/hydrologically driven temporal variations of these elements were great in the most affected streams. There were also significant positive implications regarding future environmental work; AS soils in the highlighted region were found to cause sudden temporal influxes of acidic water only in the most affected streams, indicating that the overburden and soils of the area discharge well buffered water. Moreover, it was indicated that the high (less toxic) metal concentrations are largely caused by erosion of suspended phyllosilicates (<0.45 mm) from farmland rather than by AS soils. Copyright 2011 Springer-Verlag

DOI: 10.1007/s12665-011-1216-4

12063279 Rasilo, Terhi (University of Helsinki, Department of Forest Sciences, Helsinki, Finland); Ojala, Anne; Huotari, Jussi and Pumpanen, Jukka. Rain induced changes in carbon dioxide concentrations in the soil-lake-brook continuum of a boreal forested catchment: Vadose Zone Journal, 11(2), p. vzj2011.0039-vzj2011.0039, illus. incl. 4 tables, sketch map, 52 ref., May 2012.

The numerous water bodies and their riparian zones in the boreal zone are crucial to lateral carbon transport and can thus be very significant for carbon cycle on the landscape level. Therefore, we installed automatic measurement systems with Vaisala CARBOCAP CO₂ probes (Vaisala Oyj, Vantaa, Finland) in the riparian zone soil matrix around a small headwater lake, in the lake itself, and in the outflowing brook and followed the seasonal and diurnal variation in CO₂ concentration as well as rain event-driven changes in this natural-state soil-lake-brook continuum in Southern Finland. Seasonal variation was greatest and concentrations highest deep in the soil and in the lake, but were also noticeable in the brook. On the other hand, diurnal variation was highest in shallow soil layers and the lake surface. In the brook, the influence of the riparian zone superseded that of the lake at less than 150 m distance, which resulted in wider variation and higher concentrations of CO₂. After the rain event, the normal diurnal pattern was changed, and the CO₂ concentration in the soil increased as water filled the soil pores and slowed down the diffusion. Even though the water with lower CO₂ concentration from the lake diluted the CO₂ concentration in the brook, the input from the soil dominated the flow after the rain and concentrations increased. On an annual basis, the flow of terrestrial dissolved inorganic carbon (DIC) into the aquatic ecosystem was 1-13% of terrestrial net ecosystem production (NEP).

DOI: 10.2136/vzj2011.0039

12063278 Stewart, Ryan D. (Oregon State University, Biological and Ecological Engineering Department, Corvallis, OR); Abou Najm, Majdi R.; Rupp, David E. and Selker, John S. Measurement tool for dynamics of soil cracks: Vadose Zone Journal, 11(2), p. vzj2011.0048-vzj2011.0048, illus., 26 ref., May 2012.

Shrinkage cracks in soil function as a dominant control on the partitioning and distribution of moisture fluxes in the vadose zone. Their dynamics influence the moisture balance and control water availability for runoff, deep infiltration, and near-surface storage. We present a new low-cost field instrument to monitor the temporal change in crack volume as affected by shrinkage and swelling cycles. The proposed crack-o-meter is composed of a sealed impermeable bag connected by a hose to a standpipe. An automated level logger records changes in the water level in the standpipe, which correspond to volumetric changes of the crack. The results from two laboratory experiments showed that the volume change observed by the crack-o-meter instrument scales linearly with the actual volume change, with an average error of 3%. The instrument was then used in a field experiment in Chile, where it measured the closing of cracks due to soil swelling.

DOI: 10.2136/vzj2011.0048

12058419 Waller, Richard I. (Keele University, School of Physical and Geographical Sciences, Keele, United Kingdom); Murton, Julian B. and Kristensen, Lene. Glacier-permafrost interactions; processes, products and glaciological implications: Sedimentary Geology, 255-256, p. 1-28, illus. incl. sketch maps, 210 ref., May 15, 2012.

Glaciers and permafrost represent key components of the global cryosphere. Widely held assumptions that: (1) they are largely mutually exclusive and, (2) glaciers resting on permafrost are slow moving and geomorphologically ineffectual have meant that glacier-permafrost interactions have been given little attention within the research literature. Recent research, however, has demonstrated that such interactions are likely to have been more extensive than previously thought, particularly during periods of ice-sheet growth when glaciers would have advanced over pre-existing permafrost. Work in both modern and ancient environments has revealed that subglacial processes such as basal sliding and subglacial sediment deformation can remain active at temperatures below the pressure melting point due to the persistence of premelted liquid water. Consequently, cold-based glaciers resting on permafrost are potentially more dynamic than previously thought and are capable of creating subglacial features typically viewed as only forming beneath warm-based ice. In addition, the active coupling of cold-based ice with ice-marginal permafrost means such ice masses are capable of deforming sediments and occasionally bedrock to depths of tens or even hundreds of meters and are commonly associated with the development of a range of distinctive ice-marginal landforms including push or thrust moraines and hummocky or controlled moraines. This reflects the influence of permafrost on the entrainment of debris-rich basal ice as well as the hydraulic transmissivity of the groundwater system and the associated porewater pressures within the substrate. This review considers the key characteristics of permafrost and its formation, likely extent and rheological behaviour within glacial environments. Traditional conceptions regarding the motion and landscape impact of cold-based glaciers resting on permafrost are considered before their re-examination in light of recent work demonstrating the operation of basal processes at sub-freezing temperatures. The implications for our understanding of the dynamics of glaciers and ice sheets as well as landforms and sedimentary sequences indicative of glacier-permafrost interactions are explored and exemplified with reference to modern and ancient glacial environments. Gaps in our existing knowledge are identified and profitable areas for future research suggested.

DOI: 10.1016/j.sedgeo.2012.02.005

12064876 Arzhanov, Maxim M. (Russian Academy of Sciences, A. M. Obukhov Institute of Atmospheric Physics, Moscow, Russian Federation); Eliseev, Alexey V. and Mokhov, Igor I. A global climate model based, Bayesian climate projection for northern extra-tropical land areas: Global and Planetary Change, 86-87, p. 57-65, illus. incl. 1 table, sketch maps, 66 ref., April 2012. Supplemental information/data is available in the online version of this article.

Projections with contemporary global climate models (GCMs) still markedly deviate from each other on magnitude of climate changes, in particular, in middle to subpolar latitudes. In this work, a climate projection based on the ensemble of 18 CMIP3 GCM models forced by SRES A1B scenario is performed for the northern extra-tropical land. To assess the change of soil state, off-line simulations are performed with the Deep Soil Simulator (DSS) developed at the A. M. Obukhov Institute of Atmospheric Physics, Russian Academy of Sciences (IAP RAS). This model is forced by output of the above-mentioned GCM simulations. Ensemble mean and ensemble standard deviation for any variable are calculated by using Bayesian averaging which allows to enhance a contribution from more realistic models and diminish that from less realistic models. As a result, uncertainty for soil and permafrost variables become substantially narrower. The Bayesian weights for each model are calculated based on their performance for the present-day surface air temperature (SAT) and permafrost distributions, and for SAT trend during the 20th century. The results, except for intra-ensemble standard deviations, are not very sensitive to particular choice of Bayesian traits. Averaged over the northern extra-tropical land, annual mean surface air temperature in the ensemble increases by 3.1±1.4K (ensemble mean±intra-ensemble standard deviation) during the 21st century. Precipitation robustly increases in the pan-Arctic and decreases in the Mediterranean/Black Sea region. The models agree on near-surface permafrost degradation during the 21st century. The area underlain by near-surface permafrost decreases from the contemporary value 20±3mlnsq.km to 14±3mlnsq.km in the late 21st century. This leads to risk for geocryological hazard due to soil subsidence. This risk is classified as moderate to high in the southern and western parts of Siberia and Tibet in Eurasia, and in the region from Alaska to the Labrador Peninsula in North America.

DOI: 10.1016/j.gloplacha.2012.02.001

12061524 Liu, Zhen (Case Western Reserve University, Department of Civil Engineering, Cleveland, OH); Sun, Ye and Yu, Xiong. Theoretical basis for modeling porous geomaterials under frost actions; a review: Soil Science Society of America Journal, 76(2), p. 313-330, illus. incl. 2 tables, 174 ref., April 2012.

We review the theoretical basis for modeling the behaviors of porous materials under frost actions. An attempt is made to categorize the previous research to understand the frost-induced coupled processes. The importance of the coupled processes between the thermal, hydraulic, and mechanical fields in porous materials is emphasized. Methods to describe such coupling actions are classified into basic governing mechanisms as well as the explicit and implicit relationships among individual parameters. Analytical models developed from soil science, civil engineering, and engineering mechanics are summarized. Various terminologies and expressions from different disciplines are discussed in relationship to the general physical mechanisms. From this, models can be selected for implementing holistic simulations of porous geomaterials under frost actions. We also discuss problems deserving further investigation.

DOI: 10.2136/sssaj2010.0370

12064889 Deschodt, Laurent (Institut National de Recherches Archéologiques Préventives, Villeneuve-d'Ascq, France); Salvador, Pierre-Gil; Feray, Philippe and Schwenninger, Jean-Luc. Transect partiel de la plaine de la Scarpe (Bassin de l'Escaut, Nord de la France); stratigraphie et évolution paléogéographique du Pléniglaciaire supérieur à l'Holocène récent [Partial cross section of the Scarpe Plain (Escaut Basin, northern France); stratigraphy and paleogeographic evolution of the last glacial maximum to recent Holocene]: Quaternaire (Paris), 23(1), p. 87-116 (English sum.), illus. incl. sects., 3 tables, sketch maps, 81 ref., March 2012.

The Scarpe plain is a depression in the Eocene marine sands between the Pevele and Ostrevant regions. A "high plain" is distinguished northwards from a "low plain" southwards. The infilling is mainly sandy (with a peaty part in the low plain). Numerous micro-topographies are scattered throughout the plain. The small water courses which drain the plain are not proportionate to its size. The laying of a gas pipeline across the plain was preceded by archaeological borings. We present the stratigraphy as a long cross-section and propose an evolution scenario for the plain since the Weichselian Upper Pleniglacial. The sedimentation consists mainly of sandy beds alternating with loamy laminae. This alluvial sheet, present everywhere in the plain, was deposited under strongly contrasted hydrological conditions during the Weichselian Upper Pleniglacial (OSL dates about 34, 21 and 21 ka). It may be correlated to the northern sand belt Older coversand I. Repeated avulsions of wide yet shallow channels have left deflection marks in the micro-topography. The high plain is comparable to flat and broad alluvial fans emanating from the Pevele. At the end of the Weichselian Upper Pleniglacial, under a dryer climate, small elongated dunes (sand or sand alternating with loess) formed in the center of the plain or alongside the Pevele border (OSL dates about 19 and 15 ka). This phase is at least partly contemporary with the Beuningen gravel bed. An ultimate deflation phase is imputed to the Younger Dryas. This last aeolian deposit is even fainter and looks like a thin yet continuous sheet restricted to a large southern part of the plain. Slightly scoured Late Glacial and Holocene streams can be found in the last state of Pleniglacial channels (C14 dates since 12 345 BP). The former main Pleniglacial channels may thus constitute the overbank channel of the faint Late Glacial and Holocene channels. During the Holocene, the water table rose and consecutively the peat spread in the lower areas of the plain. The widely spread yet often thin peat gradually takes over and blurs the Pleistocene topography. We have crossed three Late Glacial-Holocene channel systems (two Scarpe minor channels and an affluent). Two of them are detailed. The Vred meander bears traces of archaeological remains (a Bronze Age bridge-like structure from around 1000-800 AD) and of anthropic piracy in the upstream "Satis" during the Early Middle Ages (calcareous tufa loam flood deposits).

12061242 Multon, Stéphane (Université de Toulouse, Laboratoire Matériaux et Durabilité des Constructions, Toulouse, France); Sellier, Alain and Perrin, Bernard. Numerical analysis of frost effects in porous media; benefits and limits of the finite element poroelasticity formulation: International Journal for Numerical and Analytical Methods in Geomechanics, 36(4), p. 438-458, illus. incl. 2 tables, 30 ref., March 2012.

The aim of this paper is to analyze the performance of a finite element formulation usable for predicting the mechanical consequences of frost effects on porous media. It considers the characteristics of porous media and how the frost action can be assessed. The problem is then separated into two parts: thermal and poromechanical calculations. The constitutive equations developed in the framework of poromechanics are presented and the implementation in a usual finite element poroelasticity formulation based on Zuber's method is adopted. An analysis of the time-step influence on the convergence rate is given and leads us to propose a simple method in order to obtain objectivity of the finite element response and avoid over-long calculations. Frost effect simulations are carried out on real porous media (two fired clays) as a case study. Although the experimental behaviour of the porous media subjected to frost action is in accordance with some observations, the calculated strains appear to be overestimated compared with measurements. The problem could be largely attributable to the difficulty of assessing permeability evolution during frost development. Abstract Copyright (2010), John Wiley & Sons, Ltd.

DOI: 10.1002/nag.1014

12062986 Munroe, Jeffrey S. (Middlebury College, Department of Geology, Middlebury, VT). Physical, chemical, and thermal properties of soils across a forest-meadow ecotone in the Uinta Mountains, northeastern Utah, U.S.A.: Arctic, Antarctic, and Alpine Research, 44(1), p. 95-106, illus. incl. 5 tables, geol. sketch map, 58 ref., February 2012.

Physical, chemical and thermal properties of five pedons in the Uinta Mountains of northeastern Utah were studied to determine how soils and microclimates vary across the ecotone between subalpine forest and dry meadow. All five profiles have developed in the same parent materials, from base upward: basal till, glaciofluvial sediment, and coarse supraglacial debris with infilled eolian silt. Temperatures were measured at the soil surface and at depths of 10 and 50 cm for 420 days. Meadow soils (Typic Humicryepts) are warmer, have Bw horizons, and contain more Ca, organic carbon, and clay in the A horizon. Forest soils (Inceptic Haplocryalfs) have Bt horizons, higher B/A horizon clay ratios, are more acidic, and contain more exchangeable Mg and total exchangeable cations than meadow soils. Although subzero temperatures were never recorded at the surface of the forest soil in the summers of 1998 and 1999, those at the surface of the meadow soil fell below 0°C on ~35% of the nights. Mean 4:00 a.m. temperatures in the meadow during the summer are significantly colder than those in the forest (2.2°C vs. 5.2°C). The meadow formed following an initial forest clearing event, possibly fire or an insect infestation. Since that time, forest encroachment has been slow because seedling establishment in the meadow is inhibited by a combination of frequent summer freezing events, moisture stresses resulting from textural discontinuities between soil parent materials, and competition between tree seedlings and meadow vegetation.

DOI: 10.1657/1938-4246-44.1.95

12058251 Yang Yonggang (Shanxi University, Institute of Loess Plateau, Taiyuan, China); Xiao Honglang; Zou Songbing; Zhao Liangju; Zhou Maoxian; Hou Langong and Wang Fang. Hydrochemical and hydrological processes in the different landscape zones of alpine cold region in China: Environmental Earth Sciences, 65(3), p. 609-620, illus. incl. 1 table, geol. sketch map, 24 ref., February 2012.

Investigation of water sources and flow pathways is crucial to understand and evaluate the characteristics of surface water and groundwater systems. This article aims to identify the hydrochemical and hydrological processes in different landscape zones based on hydrochemical analyses of various samples, including samples from glacier, snow, frozen soil meltwater, surface water, groundwater, and precipitation, in the alpine cold region of China. Hydrochemical tracers indicated that chemical compositions are characterized by the Ca-HCO₃ type in the glacier-snow zone; the Mg-Ca-SO₄ type in the alpine cold desert zone; the Ca-HCO₃-SO₄ type in the marsh meadow zone; the Ca-Mg-HCO₃ type in the alpine shrub zone; and the Ca-Na-SO₄ type in the mountain grassland zone. An end-member mixing model was used for hydrograph separation. The results showed that the Mafengou River in the wet season was recharged by groundwater in the alpine cold desert and alpine shrub zones (67%), surface runoff in the glacier-snow zone (11%), surface runoff in the alpine cold desert zone (8%), thawed water from frozen soil in the marsh meadow and mountain grassland zones (9%), and direct precipitation on the river channel (5%). This study suggests that precipitation from the whole catchment yielded little direct surface runoff; precipitation was mostly transformed into groundwater or interflow and was then concentrated into the river channel. This study provides a scientific basis for evaluation and management of water resources in the basin. Copyright 2011 Springer-Verlag

DOI: 10.1007/s12665-011-1108-7

12058186 Qin Yinghong (Chinese Academy of Sciences, Laboratory of Frozen Soils Engineering, Cold and Arid Environmental and Engineering Research Institute, Lanzhou, China) and Li Guoyu. Permafrost warming under the earthen roadbed of the Qinghai-Tibet Railway: Environmental Earth Sciences, 64(7), p. 1975-1983, illus. incl. 2 tables, 32 ref., December 2011.

This paper investigates the stability of the earthen roadbed built in the warm and ice-rich permafrost region. The varying thermal regime of the subgrade and the ongoing settlement of the roadbed were observed at field. The temperature data demonstrate that in warm and ice-rich permafrost regions, adoption of earthen roadbed results in warming of the underlying permafrost. It is primarily because the earthen roadbed traps the warm-season absorbed heat in the natural ground. In addition, the carried heat of the earthen roadbed that was constructed in warm season propagates downward to warm the underlying soil. The warming permafrost layer promotes the roadbed settlement, which was mostly linearly developed in the past five service years. A comprehensive analysis for the varying thermal regime and the ongoing settlement shows that the unfrozen water liberated from the warming, undrained layer experiences consolidation. The deformation of the undrained soils is mainly responsible for settlement of the roadbed. In comparison, the temperature variation of this warming permafrost layer is found to be less beneath roadbeds protected by thermosyphons or crushed rock revetments. The installation of thermosyphons into the earthen roadbed is recommended to prevent the further degradation of the underlying permafrost. Copyright 2011 Springer-Verlag

DOI: 10.1007/s12665-011-1014-z

12065032 Lehmann-Horn, J. A. (ETH Zurich, Institute of Geophysics, Zurich, Switzerland); Walbrecker, J. O.; Hertrich, M.; Langston, G.; McClymont, A. F. and Green, A. G. Imaging groundwater beneath a rugged proglacial moraine: Geophysics, 76(5), p. B165-B172, illus. incl. geol. sketch map, 33 ref., October 2011.

With the changing precipitation patterns and melting of mountain glaciers and permafrost that result from global warming, information on the distribution of groundwater in mountainous terrains is becoming increasingly important for developing prudent resource and hazard management strategies. Obtaining this information across topographically craggy and variably frozen ground in a cost-effective and nonintrusive manner is challenging. We introduce a modified 2D surface nuclear magnetic resonance (NMR) tomographic technique that allows us to account for substantial variations in surface topography in locating and quantifying groundwater occurrences in rugged mountains. Because contact with the ground is not necessary, it is a rare geophysical technique not affected by sensor-to-ground coupling problems common in high mountain environments. To demonstrate the efficacy of the tomographic imaging scheme, we invert a large multioffset surface NMR data set collected across a partially ice-cored proglacial terminal moraine in the Canadian Rocky Mountains. Our preferred model contains a 2- to 5-m-thick water layer, the top of which has practically the same elevation as the surface of a nearby lake and the bottom of which coincides with bedrock resolved in companion seismic and ground-penetrating radar studies.

DOI: 10.1190/GEO2011-0095.1

12065034 Ramachandran, Kumar (University of Tulsa, Department of Geosciences, Tulsa, OK); Bellefleur, Gilles; Brent, Tom; Riedel, Michael and Dallimore, Scott. Imaging permafrost velocity structure using high resolution 3D seismic tomography: Geophysics, 76(5), p. B187-B198, illus. incl. 1 table, geol. sketch maps, 31 ref., October 2011.

A 3D seismic survey (Mallik 3D), covering 126 km² in the Mackenzie Delta area of Canada's north, was conducted by industry in 2002. Numerous lakes and marine inundation create a complex near-surface structure in the permafrost terrain. Much of the near subsurface remains frozen but significant melt zones exist particularly from perennially unfrozen water bodies. This results in an irregular distribution of permafrost ice creating a complex pattern of low and high frequency near-surface velocity variations which induce significant traveltime distortions in surface seismic data. A high resolution 3D traveltime tomography study was employed to map the permafrost velocity structure utilizing first-arrival traveltimes picked from 3D seismic shot records. Approximately 900,000 traveltime picks from 3167 shots were used in the inversion. Tomographic inversion of the first-arrival traveltimes resulted in a smooth velocity model for the upper 200 m of the subsurface. Ray coverage in the model is excellent down to 200 m providing effective control for estimating velocities through tomographic inversion. Resolution tests conducted through horizontal and vertical checkerboard tests confirm the robustness of the velocity model in detailing small scale velocity variations. Well velocities were used to validate tomographic velocities. The tomographic velocities do not show systematic correlation with well velocities. The velocity model clearly images the permafrost velocity structure in lateral and vertical directions. It is inferred from the velocity model that the permafrost structure in the near subsurface is discontinuous. Extensions of surface water bodies in depth, characterized by low P-wave velocities, are well imaged by the velocity model. Deep lakes with unfrozen water, inferred from the tomographic velocity model, correlate with areas of strong amplitude blanking and frequency attenuation observed in processed reflection seismic stack sections.

DOI: 10.1190/GEO2010-0353.1

12058198 Ruedrich, J. (University of Goettingen, Department of Structural Geology and Geodynamics, Geoscience Centre, Goettingen, Germany); Kirchner, D. and Siegesmund, S. Physical weathering of building stones induced by freeze-thaw action; a laboratory long-term study: in Monuments under threat; environmental impact, preservation strategies and natural stone recourses (Siegesmund, Siegfried, editor; et al.), Environmental Earth Sciences, 63(7-8), p. 1573-1586, illus. incl. 4 tables, 27 ref., August 2011.

Damages to natural building stones induced by the action of frost are considered to be of great importance. Commonly, the frost resistance of building stones is checked by standardised freeze-thaw tests before using. Corresponding tests normally involve 30-50 freeze-thaw action cycles. In order to verify the significance of such measurements, we performed long-term tests on four selected rocks over 1,400 freeze-thaw action cycles. Additionally, numerous petrophysical parameters were analysed to compare the behaviour of rocks in the weathering tests according to the current explanatory models of stress formation by growing ice crystals in the pore space. The long-term tests yield more information about the real frost sensibility of the rocks. A clear deterioration cannot be determined in most cases until 50 weathering cycles have been completed. In the freeze-thaw tests, the samples are also stressed by changing temperature and moisture, indicating that different decay mechanisms can interfere with each other. Thus, thermohygric and moisture expansion are important damage processes. Copyright 2011 Springer-Verlag and 2010 The Author(s)

DOI: 10.1007/s12665-010-0826-6

12058201 Szemerey-Kiss, B. (Budapest University of Technology and Economics, Department of Construction Materials and Engineering Geology, Budapest, Hungary) and Torok, A. Time-dependent changes in the strength of repair mortar used in the loss compensation of stone: in Monuments under threat; environmental impact, preservation strategies and natural stone recourses (Siegesmund, Siegfried, editor; et al.), Environmental Earth Sciences, 63(7-8), p. 1613-1621, illus. incl. 4 tables, 36 ref., August 2011.

Repair mortar and mixture of repair mortar with porous limestone sand aggregate were tested under laboratory conditions. Water absorption properties and micro-fabric analyses with a combination of strength tests were applied to assess the durability and compatibility of repair mortar with porous limestone. Uniaxial compressive strength and flexural strength were measured after 3, 7, 14, 28 and 90 days of casting. Durability was tested by comparing strength test results of samples kept air dry, water saturated, dried in drying chamber, freeze-thaw and non-standardized freeze-thaw cycles. The results indicate that with time various trends in strength were observed. In general, limestone aggregate content decreases more the compressive strength more than the flexural strength of the mortar. Standardized freeze-thaw tests of saturated samples caused a rapid material loss after 25 cycles, while freeze-thaw tests of undersaturated samples demonstrated that even after 100 cycles the test specimens still have a significant strength. Water-saturated samples that contain 50% of limestone aggregate have a 50% loss of strength in comparison with saturated repair mortar, while air-dry and water-saturated repair mortar has a minor strength difference after 90 days. The use of smaller amounts of porous limestone aggregate in repair mortar allow the preparation of repairs that are compatible with the monuments of Central Europe that were constructed from porous limestone. Copyright 2011 Springer-Verlag

DOI: 10.1007/s12665-011-0917-z

12057760 Wilkinson, Paul (British Geological Survey, Kingsley Dunham Centre, Keyworth, United Kingdom); Chambers, Jonathan; Kuras, Oliver; Meldrum, Philip and Gunn, David. Long term time-lapse geoelectrical monitoring: in Near-surface geoscience, First Break, 29(8), p. 77-84, illus., 34 ref., August 2011.

In this overview of research into geoelectrical monitoring at the British Geological Survey, Paul Wilkinson, Jonathan Chambers, Oliver Kuras, Philip Meldrum and David Gunn highlight the technology and algorithms that have been developed to investigate the dynamics of landslide processes, the physical integrity of vulnerable earth structures, and the thermal state of permafrost.

URL: http://www.earthdoc.org/detail.php?pubid=52134

12057652 Arp, Christopher D. (University of Alaska Fairbanks, Water and Environmental Research Center, Fairbanks, AK); Jones, Benjamin M.; Urban, Frank E. and Grosse, Guido. Hydrogeomorphic processes of thermokarst lakes with grounded-ice and floating-ice regimes on the Arctic Coastal Plain, Alaska: Hydrological Processes, 25(15), p. 2422-2438, illus. incl. 4 tables, sketch map, 80 ref., July 15, 2011.

Thermokarst lakes cover > 20% of the landscape throughout much of the Alaskan Arctic Coastal Plain (ACP) with shallow lakes freezing solid (grounded ice) and deeper lakes maintaining perennial liquid water (floating ice). Thus, lake depth relative to maximum ice thickness (1.5-2.0 m) represents an important threshold that impacts permafrost, aquatic habitat, and potentially geomorphic and hydrologic behaviour. We studied coupled hydrogeomorphic processes of 13 lakes representing a depth gradient across this threshold of maximum ice thickness by analysing remotely sensed, water quality, and climatic data over a 35-year period. Shoreline erosion rates due to permafrost degradation ranged from < 0.2 m/year in very shallow lakes (0.4 m) up to 1.8 m/year in the deepest lakes (2.6 m). This pattern of thermokarst expansion masked detection of lake hydrologic change using remotely sensed imagery except for the shallowest lakes with stable shorelines. Changes in the surface area of these shallow lakes tracked interannual variation in precipitation minus evaporation (P - E_L) with periods of full and nearly dry basins. Shorter-term (2004-2008) specific conductance data indicated a drying pattern across lakes of all depths consistent with the long-term record for only shallow lakes. Our analysis suggests that grounded-ice lakes are ice-free on average 37 days longer than floating-ice lakes resulting in a longer period of evaporative loss and more frequent negative P - _L. These results suggest divergent hydrogeomorphic responses to a changing Arctic climate depending on the threshold created by water depth relative to maximum ice thickness in ACP lakes. Abstract Copyright (2010), John Wiley & Sons, Ltd.

DOI: 10.1002/hyp.8019

12062379 Veihe, A. (Roskilde University, Department of Environmental, Social and Spatial Change, Roskilde, Denmark); Jensen, N. H.; Schiotz, I. G. and Nielsen, S. L. Magnitude and processes of bank erosion at a small stream in Denmark: Hydrological Processes, 25(10), p. 1597-1613, illus. incl. 7 tables, 58 ref., May 15, 2011.

River banks are important sources of sediment and phosphorus to fluvial systems, and the erosion processes operating on the banks are complex and change over time. This study explores the magnitude of bank erosion on a cohesive streambank within a small channelized stream and studies the various types of erosion processes taking place. Repeat field surveys of erosion pin plots were carried out during a 4-year period and observations were supplemented by continuous monitoring of volumetric soil water content, soil temperature, ground water level and exposure of a PEEP sensor. Bank erosion rates (17·6-30·1 mm year^-1) and total P content on the banks were relatively high, which makes the bank an important source of sediment and phosphorus to the stream, and it was estimated that 0.27 kg P_tot year^-1 ha^-1 may potentially be supplied to the stream from the banks. Yearly pin erosion rates exceeding 5 cm year^-1 were mainly found at the lower parts of the bank and were associated with fluvial erosion. Negative erosion pin readings were widespread with a net advance of the bank during the monitoring period mainly attributed to subaerial processes and bank failure. It was found that dry periods characterized by low soil water content and freeze-thaw cycles during winter triggered bank failures. The great spatial variability, in combination with the temporal interaction of processes operating at different scales, requires new tools such as 3-D topographical surveying to better capture bank erosion rates. An understanding of the processes governing bank erosion is required for riparian management using vegetational measures as root size and structure play different roles when it comes to controlling bank erosion processes. Abstract Copyright (2010), John Wiley & Sons, Ltd.

DOI: 10.1002/hyp.7921

12062380 Zhao Tianjie (Beijing Normal University, State Key Laboratory of Remote Sensing Science, Beijing, China); Zhang Lixin; Jiang Lingmei; Zhao Shaojie; Chai Linna and Jin Rui. A new soil freeze/thaw discriminant algorithm using AMSR-E passive microwave imagery: Hydrological Processes, 25(11), p. 1704-1716, illus. incl. 6 tables, geol. sketch map, 45 ref., May 30, 2011.

The soil freeze-thaw controls the hydrological and carbon cycling and thus affects water and energy exchanges at land surface. This article reported a newly developed algorithm for distinguishing the freeze/thaw status of surface soil. The algorithm was based on information from Advanced Microwave Scanning Radiometer Enhanced (AMSR-E) which records brightness temperature (Tb) in the afternoon and after midnight. The criteria and discriminant functions were obtained from both radiometer observations and model simulations. First of all, the microwave radiation from freeze-thaw soil was examined by carrying out experimental measurements at 18.7 and 36.5 GHz using a Truck-mounted Multi-frequency Microwave Radiometer (TMMR) in the Heihe River of China. The experimental results showed that the soil moisture is a key component that differentiates the microwave radiation behaviours during the freeze-thaw process, and the differences in soil temperature and emissivity between frozen and thawed soils were found to be the most important criteria. Secondly, a combined model was developed to consider the impacts of complex ground surface conditions on the discrimination. The model simulations quite followed the trend of in situ observations with an overall relation coefficient (R) of approximately 0.88. Finally, the ratio of Tb18.7H (horizontally polarized Tb at 18.7 GHz) to Tb36.5V was considered primarily as the quasi-emissivity, which is more reasonable and explicit in measuring the microwave radiation changes in soil freezing and thawing than the spectral gradient. By combining Tb36.5V to indicate the soil temperature variety, a Fisher linear discrimination analysis was used to establish the discriminant functions. After being corrected by TMMR measurements, the new discriminant algorithm had an overall accuracy of 86% when validated by 4-cm soil temperature. The multi-year discriminant results also provided a good agreement with the classification map of frozen ground in China. Abstract Copyright (2010), John Wiley & Sons, Ltd.

DOI: 10.1002/hyp.7930

12062135 Quinton, W. L. (Wilfrid Laurier University, Cold Regions Research Centre, Waterloo, ON, Canada); Hayashi, M. and Chasmer, L. E. Permafrost-thaw-induced land-cover change in the Canadian subarctic; implications for water resources: Hydrological Processes, 25(1), p. 152-158, illus., 29 ref., January 1, 2011.

Climate warming and human disturbance in north-western Canada have been accompanied by degradation of permafrost, which introduces considerable uncertainty to the future availability of northern freshwater resources. This study demonstrates the rate and spatial pattern of permafrost loss in a region that typifies the southern boundary of permafrost. Remote-sensing analysis of a 1·0 km² area indicates that permafrost occupied 0·70 km² in 1947 and decreased with time to 0·43 km² by 2008. Ground-based measurements demonstrate the importance of horizontal heat flows in thawing discontinuous permafrost, and show that such thaw produces dramatic land-cover changes that can alter basin runoff production in this region. A major challenge to northern water resources management in the twenty-first century therefore lies in predicting stream flows dynamically in the context of widely occurring permafrost thaw. The need for appropriate water resource planning, mitigation, and adaptation strategies is explained. Abstract Copyright (2010), John Wiley & Sons, Ltd.

DOI: 10.1002/hyp.7894

12061266 Fach, Stefan (University of Innsbruck, Institute of Infrastructure, Innsbruck, Austria); Engelhard, Carolina; Wittke, Nina and Rauch, Wolfgang. Performance of infiltration swales with regard to operation in winter times in an alpine region: Water Science and Technology, 63(11), p. 2658-2665, illus. incl. 1 table, 18 ref., 2011.

In cold climate regions winter conditions significantly influence the performance of stormwater infiltration devices. Frozen soil and water storage by snow changes their operation. In this paper winter operation of a grassed infiltration swale was investigated using on-site and laboratory measurements. The field investigation of a grassed swale at a parking place in an Alpine region showed that the swale fulfilled its function properly. Although the top layer was frozen for some time, the storage capacity of the swale was sufficient to store the precipitation until the conditions improved. The soil attenuated the air temperature, at 20 cm below ground surface the soil was only frozen for one week. Winter maintenance proved to be a problem, together with the snow from the parking place a lot of gravel and fine particles were deposited at one end of the swale. This decreased the hydraulic conductivity at that point significantly. The laboratory tests with soil columns showed an increase of flow time through the soil column with decreasing soil moisture content. For soil temperatures below 0°C the hydraulic conductivity was reduced for increasing initial soil moisture contents. All in all the hydraulic conductivity was best around 0°C for all soil water contents. However, also at minus 5°C the coefficient of hydraulic conductivity was always at least above 10^-6 m/s, thus within the range of tolerated hydraulic conductivity specified in the national guidelines. Nevertheless, the handling of the soil was found to have high influence on the results. The results indicate that in the Alpine region infiltration swales operate sufficiently under winter conditions although with decreased performance.

DOI: 10.2166/wst.2011.153

12062645 Szczucinska, Anna Maria (Uniwersytet im. Adama Mickiewicza, Instytut Geografii Fizycznej i Ksztaltowania Srodowiska Przyrodniczego, Poznan, Poland). Occurrence and temporal variations of groundwater outflows in the Petuniabukta region, Spitsbergen: Polish Polar Research, 32(4), p. 361-374, illus. incl. 1 table, geol. sketch map, 42 ref., 2011.

The occurrence and temporal variations of polar shallow groundwater systems and associated seasonal springs and seeps are studied using the example of springs and seeps in the vicinity of the eastern coast of Petuniabukta in central Spitsbergen, Svalbard. Altogether, 37 groundwater outflows were documented. The outflows were mostly located at the foot of talus slopes and were characterised by small discharges (<1 dm³ s^-1. The water emerging from the outflows varied widely in terms of temperature and specific electrical conductivity (SpC). These outflows were supplied mainly by water from permafrost, melting snowfields and rainfall. Daily changes were studied in four of the outflows during July 2006. The observed water discharges ranged from 0.04 to 0.7 dm³ s^-1, and the temporal variations for the particular outflows were on the order of 50% of the average value. The water temperature amplitude for particular outflows was up to 1.5°C. The SpC was approximately 200 mS cm^-1 and increased with time by almost 40 mS cm^-1 and in the case of two outflows draining talus slopes. The water emerging from two springs in carbonate and sulphate rocks had an SpC up to 1295 mS cm^-1, and in one case, its increase with time was observed to be 300 mS cm^-1. The increase in the SpC with time probably reflects a decrease in the contribution of snow meltwater in the groundwater recharge. Among the major local factors affecting the groundwater outflows' water quality and discharge rate were the following: geomorphology, rock type, meteorological conditions, state of permafrost and local water storage.

DOI: 10.2478/v10183-011-0023-7

12061842 Nikolayeva, N. A. (Rossiyskaya Akademiya Nauk, Sibirskoye Otdeleniye, Institut Fiziko-Tekhnicheskikh Problem Severa, Yakutsk, Russian Federation). Prognoz gidrokhimicheskogo sostoyaniya vody proyektiruyemykh vodokhranilishch GES Yuzhnoy Yakutii [Forecasting the hydrochemical state of the water in the projected reservoirs of the hydroelectric stations in southern Yakutia]: Geografiya i Prirodnyye Resursy, 2010(3), p. 120-125 (English sum.), 4 tables, 7 ref., September 2010.

A preliminary forecast of the hydrochemical state of the water in the future reservoirs of the hydroelectric stations in southern Yakutia is provided. The expected content is calculated for a number of organic and biogenic substances, the sources of which are provided by the river runoff, woody vegetation and soils. A forecast is made of the content of dissolved oxygen and of the water mineralization in the future reservoirs.

12061836 Tregubov, O. D. (Rossiyskaya Akademiya Nauk, Dal'nevostochnoye Otdeleniye, Severo-Vostochnyy Kompleksnyy Nauchno-Issledovatel'skiy Institut, Anadyr, Russian Federation). Faktory i mekhanizmy samovosstanovleniya gorno-tundrovykh landshaftov Chukotki [Self-regenerating factors and mechanisms for mountain-tundra landscapes of Chukchi]: Geografiya i Prirodnyye Resursy, 2010(3), p. 38-43 (English sum.), 2 tables, 11 ref., September 2010.

Stability of mountain-tundra landscapes of Chukchi is treated as the capacity of geosystems for natural restoration. In this case study of a number of mining sites with a restoration period of 25-40 years, the effect of exogenous and biogenic factors is analyzed. It is concluded that the mountain-tundra landscapes are distinguished by plastic stability and that phytogenic and cryogenic processes have a dissimilar influence on geosystem restoration.

12061837 Zabolotnik, S. I. (Rossiyskaya Akademiya Nauk, Sibirskoye Otdeleniye, Institut Merzlotovedeniya, Yakutsk, Russian Federation). Surovost' klimaticheskikh usloviy na territorii Rossii [The harshness of climatic conditions in the territory of Russia]: Geografiya i Prirodnyye Resursy, 2010(3), p. 69-74 (English sum.), sketch map, 32 ref., September 2010.

An assessment is made of the harshness of climatic conditions and the distribution pattern of the permafrost zone in the territory of Russia. The regionalization map for the Russian Federation territory has been compiled, based on analyzing long-term air temperature observations from more than 3000 meteostations. Six natural-climatic zones are identified on the map. The harshest conditions were determined to be north of 60 ° N in Yakutia, where the Pole of Cold in the the Northern Hemisphere is located, and in the adjacent areas of Krasnoyarsk territory and the Magadan region. The regions in the western European part of Russia, where no formation of permafrost whatsoever occurs, are recognized as the most favorable for the life of the population.

12056999 Luoto, Miska (University of Oulu, Department of Geography, Oulu, Finland); Marmion, Mathieu and Hjort, Jan. Assessing spatial uncertainty in predictive geomorphological mapping; a multi-modelling approach: Computers & Geosciences, 36(3), p. 355-361, illus. incl. 2 tables, sketch map, 39 ref., March 2010.

Maps of earth surface processes and the potential distribution of landforms make an important contribution to theoretical and applied geomorphology. Because decision making often depends on information based on spatial models, there is a great need to develop methodology to evaluate the spatial uncertainty resulting from those models. In this study we developed a new method to produce maps of the uncertainty of predictions provided by ten state-of-the-art modelling techniques for sorted (SP) and non-sorted (NSP) patterned ground in subarctic Finland at a 1.0-ha resolution. Six uncertainty classes represent the modelling agreement between the different modelling techniques. The resulting uncertainty maps reflect the reliability of the estimates for the studied periglacial landforms in the modelled area. Our results showed a significant negative correlation between the degree of uncertainty and the accuracy of the modelling techniques. On average, when all ten models agreed, the mean area under the curve (AUC) values were 0.904 (NSP) and 0.896 (SP), these values decreased to 0.416 (NSP) and 0.518 (SP), respectively, when only five models agreed. Mapping of the uncertainty of predictions in geomorphology can help scientists to improve the reliability of their data and modelling results. The predictive maps can be interpreted simultaneously with the uncertainty information, improving understanding of the potential pitfalls of the modelling.

DOI: 10.1016/j.cageo.2009.07.008

Back to the Top

12061413 Abramov, A. A. (Rossiskaya Akademiya Nauk, Institut Fiziko-Khimicheskikh i Biologicheskikh Problem Pochvovedeniya, Pushchino, Russian Federation); Mironov, V. A.; Lupachev, A. V.; Fedorov-Davydov, D. G.; Goryachkin, S. V.; Mergelov, N. S.; Ivashchenko, A. I.; Lukin, V. V. and Gilichinskiy, D. A. Geokriologicheskiye usloviya antarkticheskikh oazisov [Geocryological conditions in Antarctic oases]: in Polyarnaya kriosfera i vody sushi (Kotlyakov, V. M.), in the collection Vklad Rossii v Mezhdunarodnyy Polyarnyy God 2007/08ýT Russian contribution to International Polar Year 2007/08. Paulsen Editions, Moscow, Russian Federation, p. 233-241 (English sum.), illus. incl. 2 tables, 14 ref., 2011.

During the IPY the monitoring network have been organized near coastal Russian Antarctic stations. It is consist of boreholes for ground temperatures monitoring and sites for active layer depth measurements. The maximum active layer depth (>1.2 m) and mean annual ground temperature (-0.6°C) have been observed at Bellingshausen station--on the northern permafrost boundary. The minimal temperatures have been observed at Russkaya station (-10,8°C), where only daily thawing is possible for few centimeters. The ground temperatures and active layer depth at Progress, Banger hills, Novolazarevskaya and Molodejnaya are similar and lies in between. The observed data let us to estimate the geocryological conditions of Antarctic oasis's and will be the 0-point for future changes estimation.

12061407 Anisimov, O. A. (Gosudarstvennyy Gidrologicheskiy Institut, Saint Petersburg, Russian Federation) and Reneva, S. A. Uglerodnyy balans v kriolitozone Rossii i global'nyy klimat; sovremennoye sostoyaniye i prognoz, osnovannyy na modelirovanii [Balance of carbon in the Russian permafrost zone and global climate; current data and prediction based on numerical models]: in Polyarnaya kriosfera i vody sushi (Kotlyakov, V. M.), in the collection Vklad Rossii v Mezhdunarodnyy Polyarnyy God 2007/08ýT Russian contribution to International Polar Year 2007/08. Paulsen Editions, Moscow, Russian Federation, p. 122-139 (English sum.), illus. incl. 2 tables, sketch map, 37 ref., 2011.

The current dynamic of permafrost in Russia is considered in the context of potential impact of greenhouse gas emissions on global climate. The estimation of permafrost soil carbon stocks on the basis of the specified published data is given. Mathematical model has been used to predict changes in the temperature and seasonal thaw depth of the frozen ground using 1960-2008 meteorological data and mid-21st century climatic projections based on 5 GCMs. Model results are compared against observed trends. Projected soil temperature and the depth of seasonal thawing are used in carbon model to estimate the greenhouse emissions under future climatic conditions and potential feedback to global climate. Large amounts of soil carbon deposited in permafrost may be released due to deeper seasonal thawing under the climatic conditions projected for the future. Particular concerns are associated with methane, which has a much stronger greenhouse effect than an equal amount of CO₂. To evaluate the effect of such changes on the volume of the seasonally thawing organic material, we overlaid the permafrost projections on the digitized geographically referenced contours of wetlands in the Russian Arctic. Results for the mid-21st century climate indicated up to 50% increase in the volume of organic substrate in the northernmost locations along the Arctic coast and in East Siberia, where wetlands are sparse, and a relatively small increase by 10%-15% in West Siberia, where wetlands occupy 50%-80% of the land. We developed a soil carbon model and used it to estimate the changes in the methane fluxes due to higher soil temperature and increased substrate availability. According to our results, by mid-21st century the annual net flux of methane from Russian permafrost regions may increase by 6-8 Mt, depending on climatic scenario. If other sinks and sources of methane remain unchanged, this may increase the overall content of methane in the atmosphere by approximately 100 Mt, or 0.04 ppm, and lead to 0.012°C global temperature rise. Uncertainty of this result is discussed.

12061418 Debol'skiy, V. K. (Rossiskaya Akademiya Nauk, Institut Vodnykh Problem, Moscow, Russian Federation); Debol'skaya, Ye. I.; Kotlyakov, A. V. and Maslikova, O. Ya. Matematicheskoye modelirovaniye deformatsiy rusla v nizhnikh b"yefakh GES, raspolozhennykh v kriolitozone, pri katastroficheskikh navodneniyakh i v usloviyakh ledovykh zatrudneniy [Mathematical modeling of channel deformation in lower reaches of hydroelectric power plants in the permafrost zone under conditions of ice jams and catastrophic floods]: in Polyarnaya kriosfera i vody sushi (Kotlyakov, V. M.), in the collection Vklad Rossii v Mezhdunarodnyy Polyarnyy God 2007/08ýT Russian contribution to International Polar Year 2007/08. Paulsen Editions, Moscow, Russian Federation, p. 305-317 (English sum.), illus., 3 ref., 2011.

The influence of ice regime on the river channel processes and processes of shore reformation in the rivers of arctic and near arctic regions is considered, as well as an effect of the ice cover on the river channel and shore near the waterworks facility. The mechanisms of this effect are described under the different conditions of the ice cover. The mathematical models of bottom deformations in ice-covered flow in the downstream reach of hydraulic structure and numerical model of ice jam formation due to release wave are suggested. These models allow one to follow the propagation of the release wave in ice-covered river channel of irregular morphometry; ice jam formation and change of river flow characteristics because of release wave; inundation due to ice jam and the influence of riverbed forms on the scales of ice and flow interaction. Because of numerical modeling the forecasts of the conditions of ice jams formation, catastrophic rise of water level and the velocity of its propagation, can be obtained. The mathematical model is developed, which enables one to discover the most important factors and the combination of them affecting on the propagation of pollutants during the ice jam formation, and to evaluate the order and area of pollution due to winter inundation.

12061409 Drozdov, D. S. (Rossiskaya Akademiya Nauk, Sibirskoye Otdeleniye, Institut Kriosfery Zemli, Tyumen, Russian Federation); Vasil'yev, A. A.; Malkova, G. V.; Moskalenko, N. G.; Orekhov, P. T. and Ukraintseva, N. G. Izmeneniya temperatury mnogoletnemerzlykh porod zapadnogo sektora rossiyskoy Arktiki v svyazi s izmeneniyami klimata [Variations of permafrost temperature in the western Russian Arctic with regard to climate change]: in Polyarnaya kriosfera i vody sushi (Kotlyakov, V. M.), in the collection Vklad Rossii v Mezhdunarodnyy Polyarnyy God 2007/08ýT Russian contribution to International Polar Year 2007/08. Paulsen Editions, Moscow, Russian Federation, p. 153-170 (English sum.), illus. incl. sketch map, 38 ref., 2011.

Geocryological monitoring and mapping of particular northern territories are based on the regime observations at special key-sites followed by extrapolation of the obtained data using regional and local landscape maps as the graphical models. The in-situ observations and processing of geocryological data are held concerning the variability and fluctuations climatic parameters. The cryosphere response to the climatic changes has a significant inertia because of low thermal conduction in soil and ground, phase transition, influence of snow-cover, precipitations, biota, etc. Nevertheless the climatic study precede the geo-cryological interpretation of data. It is a key to understanding of modern trends in evolution of cryolithozone and response of geosystems of the North. Weather station records show that the maximum warming rate was observed in 1980-s. In Russia, centers of warming in XX century was Central Yakutia and Transbaikal, while in the European and Far East Russia the rate of warming was rather low. Starting with the second half of 1990-s mean annual air temperature warming trend was observed only locally, while in other places warming slowed down or even stopped. This is clearly demonstrated by regression lines for mean annual air temperature monitored at the basic weather stations in 1965-1995 and 1990-2005. Taken into account the last climate changes, new areas of maximum rates of warming begin to show within Russian cryolithozone. Warming gradually extends to the Arctic regions while it slows down in Subarctic. The data on the mean annual permafrost temperature dynamics at several geocryological key-sites in Russian Arctic is presented (island Belyi, Marre-Sale, Bolvanskii cape, Urengoy, Nadym). It is proved that during last 30-35 years an increase in the mean annual permafrost temperature is well expressed. But it is important to mention that permafrost temperature changes are not similar for various landscapes and different periods. Maximum ground temperature was observed in 1990-s and then the rate of permafrost warming slow down. Low-temperature permafrost has been warmed more than high-temperature frozen ground. The last decade of air and ground temperature observations allows to expect the reversion of the warming cycle to temperature lowering cycle. Simultaneously this temperature reduction the expansion of open-forests to the north indicating lowering of the permafrost table is observed widely in forest-tundra zone.

12061411 Goryachkin, S. V. (Russian Academy of Sciences, Institute of Geography, Moscow, Russian Federation); Gilichinskiy, D. A.; Gubin, S. V.; Lapteva, Ye. M.; Lupachev, A. V.; Fedorov-Davydov, D. G.; Zazovskaya, E. P.; Mazhitova, G. G.; Mergelov, N. S.; Vinogradova, Yu. A.; Melekhina, Ye. N. and Taskayeva, A. A. Sostoyaniye arkticheskikh i subarkticheskikh pochv na period Mezhdunarodnogo polyarnogo goda [Characteristics of Arctic and sub-Arctic soils during the International Polar Year]: in Polyarnaya kriosfera i vody sushi (Kotlyakov, V. M.), in the collection Vklad Rossii v Mezhdunarodnyy Polyarnyy God 2007/08ýT Russian contribution to International Polar Year 2007/08. Paulsen Editions, Moscow, Russian Federation, p. 193-217 (English sum.), illus. incl. 13 tables, 16 ref., 2011.

The state of several dynamic parameters of polar soils for the period of the International Polar Year 2007-2008 is shown. In 2007 and 2008 the data on tundra soils of the Vorkuta tundra, Northern Yakutia and Spitsbergen has been collected and analyzed. It was found out that the nano-relief of permafrost table surfaces, the texture of frozen substrates, ice content and the change of a water regime of supra-permafrost soil horizons during the maximum thawing lead to active lateral migration of soil material on a frozen ground surface, its redistribution between elements of patterned ground and to formation of deep supra-permafrost accumulations of organic material. The thawing depth of soils of Low-Kolyma lowland depends on not only a climate and a temperature regime of each concrete year, but also on parent materials, the character of the top horizons of soils, presence or absence of flooding, precipitation of autumn time. It was distinguished that it is not enough reason to relate the tendency of thawing depth increase with the climate warming or with any other global reasons--the maximal depths of soil thawing observed in 1991, 2002-2005 and 2007, most likely, correspond to temperature maxima of intracentury climatic cycles. The relation of structure and distribution of microfauna with a soil temperature regime of Vorkuta tundra is shown. Collembolans and oribatides occupy organic horizons (including a layer of live mosses) of permafrost soils of moss-lichen tundra while the mesofauna communities in soils with a different temperature regimes are close on structure and content. In tundra soils the most dense population of microfauna is observed in superficial horizons--in a layer of live mosses and weakly decomposed soil litter. In the bottom part of a soil litter and in mineral horizons the population sharply decreases. The new species from the Byrrhidae family--Cytilus auricomus for the European northeast of Russia was detected. It was also shown that in the investigated soils of Spitsbergen the superficial horizons have lower rates of a carbon exchange and, accordingly, more ancient radiocarbon age, than earlier received dates. Thus, in high latitudes of Arctic the acceleration of an exchange of soil carbon is not observed, despite global warming.

12061410 Leybman, M. O. (Rossiskaya Akademiya Nauk, Sibirskiy Otdeleniya, Institut Kriosfery Zemli, Tyumen, Russian Federation); Moskalenko, N. G.; Orekhov, P. T.; Khomutov, A. V.; Gameyev, I. A.; Khitun, O. V.; Walker, D. A. and Epstein, H. E. Vzaimodeystviye kriogennykh i biotichekikh komponent geosistem v kriolitozone Zapadnoy Sibiri na transekte "Yamal" [Interaction of cryogenic and biogenic factors in permafrost systems of West Siberia studied along the "Yamal" transect]: in Polyarnaya kriosfera i vody sushi (Kotlyakov, V. M.), in the collection Vklad Rossii v Mezhdunarodnyy Polyarnyy God 2007/08ýT Russian contribution to International Polar Year 2007/08. Paulsen Editions, Moscow, Russian Federation, p. 171-192 (English sum.), illus. incl. 9 tables, sketch map, 56 ref., 2011.

Five research polygons along the transect "Yamal" were under study within the framework of several IPY projects (TSP, CALM, GOA) covering five bioclimatic subzones from northern taiga in the south through to the Arctic tundra in north. Measurements were performed on study sites during 1-3 summer seasons within standard plots characterized by relief, geological structure, surface properties and cryogenic processes. The plots are equipped for measurement of ground temperature, depth of seasonal thaw, vegetation indexes and other parameters of vegetation. Plant communities are described. The zonal patterns in the spatial distribution of various parameters of cryolithozone and biota, as well as manifestations of cryogenic and biotic components within geosystems are presented. It is established that, on the whole, zonal distribution of bioclimatic subzones northward determines the consecutive change of various parameters of vegetation, and permafrost. However, local factors connected to relief, drainage degree, location of plots on different landforms determining snow accumulation distort zonal pattern which is much more apparent when similar landscapes are compared. Application of quantitative methods of vegetation study has allowed to consider its interrelation with components of cryolithozone. The zonal changes of vegetation indexes, depth of thaw, and ground temperature from south northward in similar landscape conditions are determined by the reduction of biomass in this direction. The zonal pattern is clearer traced within the landscapes on clayey soils.

12061412 Osokin, N. I. (Rossiskaya Akademiya Nauk, Institut Geografii, Moscow, Russian Federation); Sosnovskiy, A. V.; Nakalov, P. R. and Chernov, R. A. Klimaticheskiye izmeneniya i vozmozhnaya dinamika mnogoletnemerzlykh gruntov na Shpitsbergene i Antarkticheskom poluostrove [Climate change and possible permafrost dynamics in Spitsbergen and the Antarctic Peninsula]: in Polyarnaya kriosfera i vody sushi (Kotlyakov, V. M.), in the collection Vklad Rossii v Mezhdunarodnyy Polyarnyy God 2007/08ýT Russian contribution to International Polar Year 2007/08. Paulsen Editions, Moscow, Russian Federation, p. 218-232 (English sum.), illus. incl. 1 table, 9 ref., 2011.

The temperature of air and snow cover influence temperature and depth of the permafrost melting. Variation of annual, negative and positive average daily temperatures of air in area of Antarctic peninsula (Bellingshausen station) and Spitsbergen (Barentsburg station) is considered. Linear trends of temperature of air for all period of supervision and for last 10 years are received. Variation of thickness of a snow cover and quantity of firm precipitations for the cold period of year is given. Results of calculations of freezing and melting a ground within with abnormal values of temperature of air and thickness of a snow cover are submitted. Variation of temperature of a ground on different depths these years is calculated. The moss cover reduces growth of temperature and depth of melting of a ground. Heat-physical properties of some kinds of a moss are investigated. The estimation of their influence on freezing and melting of permafrost is given. Trends of coefficient of heat conductivity of some kinds of a moss during the warm and cold periods of year are received. Comparison of value of heat conductivity of a moss and coefficient of effective heat conductivity of a snow cover carried out. On the basis of mathematical modeling and numerical experiments draws the conclusion about possible influence of modern climatic changes on a condition of permafrost and their dynamics.

12061416 Shiklomanov, I. A. (Gosudarstvennyy Gidrologicheskiy Institut, Saint Petersburg, Russian Federation); Georgiyevskiy, V. Yu.; Shiklomanov, A. I. and Golovanov, O. F. Novyye dannyye o stoke krupneyshikh rek, vpadayushchikh v Severnyy Ledovityy okean [New data on discharge of the largest rivers into the Arctic Ocean]: in Polyarnaya kriosfera i vody sushi (Kotlyakov, V. M.), in the collection Vklad Rossii v Mezhdunarodnyy Polyarnyy God 2007/08ýT Russian contribution to International Polar Year 2007/08. Paulsen Editions, Moscow, Russian Federation, p. 265-287 (English sum.), illus. incl. 4 tables, sketch map, 34 ref., 2011.

Analysis of changes in annual and seasonal discharge of the largest Eurasian (Yenisei, Lena, Ob, Kioyma, Pechora, Severnaya Dvina) and North American (Mackenzie and Yukon) rivers contributing to the Arctic Ocean based on observational data for the pan-Arctic drainage basin is given for periods 1980-2008 and 2000-2008 relative to period of stationary climate (1936-1979). River discharge during the second period (2000-2008) was the greatest for all analyzed rivers and over the last 8 years the ocean additionally received about 1600 km³ of fresh water from these river basins alone. Eurasian rivers demonstrated especially high discharge over this period with historical maximums of total discharge in 2007 which exceeded average annual discharge over 1936-2006 by 25%. The analysis showed the formation of record-high discharge in 2007 and increased runoff after 1980 was due to higher precipitation and, evidently, more intensive thawing of permafrost under increasing air temperature and 2007 was the warmest in the given river basins over the entire observational period. It is important to note that the period after 1980, when the intensive climate warming began in high latitudes of the Northern Hemisphere, is characterized with very significant change in discharge of Russian rivers to the Arctic Ocean. The slope of the linear trend line over this period was 4 times steeper than over entire observational period since 1936. The changes in seasonal discharge of Eurasian and North American rivers and their possible causes are discussed in the paper. The results, obtained by Russian and foreign scientists in recent years, for future projections of runoff across the Arctic Ocean drainage basin under influence of global warming confirmed conclusions made in the 1990s. In general, they show that pan-Arctic rivers are expected to increase in discharge during the next few decades reaching about 10-20% of their present values by the middle of the 21st century.

12061408 Vasil'yev, A. A. (Rossiskaya Akademiya Nauk, Sibirskoye Otdeleniye, Institut Kriosfery Zemli, Tyumen, Russian Federation); Shirokov, R. S.; Streletskaya, I. D.; Oblogov, G. Ye.; Cherkashev, G. A. and Vanshteyn, B. G. Beregovyye protsessy v kriolitozone v usloviyakh menyayushchegosya klimata [Coastal processes in the permafrost zone with regard to climate change]: in Polyarnaya kriosfera i vody sushi (Kotlyakov, V. M.), in the collection Vklad Rossii v Mezhdunarodnyy Polyarnyy God 2007/08ýT Russian contribution to International Polar Year 2007/08. Paulsen Editions, Moscow, Russian Federation, p. 140-152 (English sum.), illus. incl. 1 table, 24 ref., 2011.

Coastal processes and formation of thermal regime in the coastal zone of the Kara Sea (West Yamal) are discussed. The scheme of the coastal zone division was developed for the western sector of the Russian Arctic, including West Yamal. The division is based on conditions of heat exchange of freezing and/or thawing soils. This scheme can be applied for all types of coasts, including thermoerosional, accumulative, and stable coasts. The data on climate, environment, and hydrology of the Kara Sea have been accumulated. Fluctuating mean annual air temperatures have been generally increasing during the last decades. In different regions, the amplitude of such increase can be different. Mean annual air temperature in the coastal zone of West Yamal had increased at 1°C from 1972 to 2009. A close correlation between mean annual air temperatures and near-bottom shallow-water temperatures in the Kara Sea was determined. The near-bottom temperature in the area to the west from Malygin Strait at depths up to 65 m had increased at 0.2-0.3°C from 1920's to the end of 1990's. The thickness of seasonal ice has decreased from 150 cm to 120 cm (1998-present). The width of ad freezing band of seasonal ice is about 150 m at accumulative coasts and 90 m at thermoerosional coasts. Vertical deformations of beaches and offshore slopes are about 0.5 m/year. Coastal retreat rates are 0.5-3.3 m/year (from 1978 to present). Mean annual ground temperature in the areas of degrading permafrost of beaches is about -1°C, which is close to the freezing point. In the areas of aggrading permafrost, mean annual ground temperature is about -3.3°C. Permafrost temperature records onshore and offshore (both in the areas of permafrost degradation and aggradation) show positive climatic signal, which results either in accelerating of permafrost degradation or in slowdown of permafrost.

Back to the Top

12062659 Liu, Lin. Studying changes in the cryosphere using radar interferometry; permafrost surface subsidence and glacial unloading deformation: 176 p., Doctoral, 2011, University of Colorado at Boulder, Boulder, CO. ISBN: 978-1-124-62102-9 Available from: Univ. Microfilms.

Back to the Top

12058397 Langston, Gregory (University of Calgary, Department of Geoscience, Calgary, AB, Canada); Bentley, Laurence R.; Hayashi, Masaki; McClymont, Alastair and Pidlisecky, Adam. Internal structure and hydrological functions of an alpine proglacial moraine: in Canadian Geophysical Union, Hydrology Section; special issue (Branfireun, Brian, editor; et al.), Hydrological Processes, 25(19), p. 2967-2982, illus. incl. sketch map, 60 ref., September 15, 2011. Meeting: Canadian Geophysical Union annual meeting, May 31-June 4, 2010, Ottawa, ON, Canada.

Understanding groundwater processes in alpine watersheds is critical to understand the timing of water release and late-season stream flow for both headwater and downstream environments. Moraines and talus features can play an important role in groundwater flow and storage processes in alpine watersheds, but neither process is well understood for these features. We examined the complex hydrogeological environment of a partially ice-cored moraine in the Lake O'Hara watershed in the Canadian Rockies. Electrical resistivity imaging (ERI) and seismic refraction tomography delineated regions of buried ice and frozen and unfrozen moraine material. Seismic refraction data also clearly indicated the depth to bedrock, which varied primarily due to the thickness of the overlying moraine material. Water levels in a lake and several tarns on the moraine responded differently to inputs of rain, snowmelt, and glacier melt, indicating the different degree of hydrological connectivity of these features to the groundwater flow system in the moraine. Such differences reflect the effects of bedrock topography and the location and geometry of buried ice. Ground-penetrating radar images and ERI indicated regions of perched groundwater and focused infiltration. The location of these regions appears to be controlled by buried ice. All geophysical and hydrological data suggest that a relatively thin (<5 m) layer of saturated sediments and/or fractured bedrock likely provides a major flow system within the moraine. Abstract Copyright (2010), John Wiley & Sons, Ltd.

DOI: 10.1002/hyp.8144

12064599 Desrochers, S. (Université du Québec à Montréal, GEOTOP, Montreal, QC, Canada); Stevenson, R. K.; Hélie, J. F. and Poirier, A. Use of stable (HOCN) and radiogenic (Sr) isotopes to determine the geographic provenance and traceability of artisanal cheeses of Quebec, Canada [abstr.]: in Goldschmidt 2011 abstract volume, Mineralogical Magazine, 75(3), p. 753, 6 ref., 2011. WWW. Meeting: Goldschmidt2011, Aug. 8-14, 2011, Prague, Czech Republic.

Analysis of stable isotopes has often been used to determine the traceability of different food products [1] The light stable isotope ratios in dairy products such as cheese can provide information for tracing geographical origin. [4] The province of Quebec is Canada's largest cheese producer and artisanal cheeses are becoming a larger part of this market. In this context, we selected artisanal cheeses from six different regions of the province of Quebec to study the applicability of light stables isotopes and radiogenic isotope (Sr) ratios as discriminants to provide geographic traceability. The cheese samples were analysed for light stable isotope ratios (HOCN) which are mainly influenced by altitude, distance from the sea, use of fertilizer, rainfall, food type, temperature, longitude and latitude [2,3,6]. The Sr isotope analyses are indicative of the geology of the type of substrate of the grazing areas [5]. Preliminary results yield ⁸⁷Sr/⁸⁶Sr ratios that vary from 0.71084 to 0.71347. These values reflect soils composed largely of glacial tills derived from either the Canadian shield or Appalachian Orogen. Stable isotope dD values vary between -103.06ppm to -55.74ppm, and d¹⁸O between -17.99ppm to -7.54ppm. In addition, samples of the food, water, soil and raw milk will also be analysed to determine if enrichment or depletion of the different stable isotope ratios occurs during the manufacture of milk and during the conversion of milk to cheese.

URL: http://minmag.geoscienceworld.org/content/75/3/712.full.pdf+html

12064604 Dickinson, W. W. (Victoria University, Antarctic Research Center, Wellington, New Zealand); Schiller, M.; Ditchburn, B. G.; Graham, I. J. and Zondervan, A. Soil closure ages from meteoric ¹⁰Be, McMurdo dry valleys, Antarctica [abstr.]: in Goldschmidt 2011 abstract volume, Mineralogical Magazine, 75(3), p. 755, 2011. WWW. Meeting: Goldschmidt2011, Aug. 8-14, 2011, Prague, Czech Republic.

Understanding Neogene polar climate in the McMurdo Dry Valleys relies largely on evidence from landscape evolution, glacial modelling and stratigraphy. We provide new evidence from meteoric ¹⁰Be for the onset of frozen, hyper-arid conditions in Dry Valley soils. A simple decay model for the co-occurrence of ¹⁰Be and illuviated clay in two adjacent profiles indicates the clays were actively migrating down from the surface in a warmer climate until the system froze between 6 and 9 Ma. The model also suggests denudation rates of 0.02-0.06 m Myr^-1 since closure. These data provide an independent test to glacial-stratigraphic evidence used to determine Antarctic paleoclimate. Clays bound with meteoric ¹⁰Be are prevalent in many Dry Valley soils to depths of over 4 m. These particles, which are now frozen in place, were illuviated by percolating water from the surface, during a previous "wet period". We use two adjacent profiles to take advantage of the ¹⁰Be clock and determine when ¹⁰Be was sealed or closed off from the surface. The two-profile method allows elimination of several variables and hence, calculation of how long ¹⁰Be has been in the soil since freezing or closure. By sampling soils at a variety of altitudes and locations, we may build up a better picture of the transformation from sub-polar to polar conditions in the Dry Valleys.

URL: http://minmag.geoscienceworld.org/content/75/3/712.full.pdf+html

12057737 Bagard, M. L. (Université de Strasbourg, Laboratoire d'Hydrologie et de Géochimie, Strasbourg, France); Chabaux, F.; Pokrovsky, O. S.; Prokushkin, A. S.; Viers, J.; Derenne, S. and Templier, J. Source of colloidal and dissolved loads over the hydrological cycle in Siberian rivers [abstr.]: in Abstracts of the 20th annual V. M. Goldschmidt conference, Geochimica et Cosmochimica Acta, 74(12, Suppl. 1), p. A40, 1 ref., 2010. Meeting: 20th annual V. M. Goldschmidt conference, June 13-18, 2010, Knoxville, TN.

URL: http://goldschmidt2010.org/abstracts/A-Z+Index.pdf

12057096 Clifford, S. M. (Lunar and Planetary Institute, Houston, TX) and Lasue, J. The evolution and fate of groundwater on Mars; the influence of modeling assumptions and consistency of predictions with observational constraints: in Lunar and planetary science conference XLI; papers presented to the Forty-first lunar and planetary science conference, Abstracts of Papers Submitted to the Lunar and Planetary Science Conference, 41, Paper 2739, 7 ref., 2010. Meeting: Forty-first lunar and planetary science conference, March 1-5, 2010, Houston, TX. Accessed on July 29, 2011.

URL: http://www.lpi.usra.edu/meetings/lpsc2010/pdf/2739.pdf

12057035 Elder, C. M. (University of Arizona, Lunar and Planetary Laboratory, Tucson, AZ); Bray, V. J. and Melosh, H. J. Central pit formation in Ganymede craters via melt drainage: in Lunar and planetary science conference XLI; papers presented to the Forty-first lunar and planetary science conference, Abstracts of Papers Submitted to the Lunar and Planetary Science Conference, 41, Paper 2519, illus. incl. 1 table, 13 ref., 2010. Meeting: Forty-first lunar and planetary science conference, March 1-5, 2010, Houston, TX. Accessed on July 26, 2011.

URL: http://www.lpi.usra.edu/meetings/lpsc2010/pdf/2519.pdf

12057102 Hauber, E. (Deutsches Zentrum für Luft- und Raumfahrt, Institut für Planetenforschung, Berlin, Germany); Reiss, D.; Ulrich, M.; Krohn, K.; Preusker, F.; Trauthan, F.; Zanetti, M.; Hiesinger, H.; van Gasselt, S.; Jaumann, R.; Johansson, L.; Johnsson, A. and Olvmo, M. Debris flow fans and permafrost landforms on Svalbard (Norway); terrestrial analogues for Martian mid-latitude periglacial landscapes: in Lunar and planetary science conference XLI; papers presented to the Forty-first lunar and planetary science conference, Abstracts of Papers Submitted to the Lunar and Planetary Science Conference, 41, Paper 1922, illus., 40 ref., 2010. Meeting: Forty-first lunar and planetary science conference, March 1-5, 2010, Houston, TX. Accessed on July 29, 2011.

URL: http://www.lpi.usra.edu/meetings/lpsc2010/pdf/1922.pdf

12057103 Kowalewski, D. E. (University of Massachusetts at Amherst, Department of Geosciences, Amherst, MA); Morgan, G. A.; Marchant, D. R. and Head, J. W., III. Influence of textural and topographic variability on sublimation of buried ice; implications for near surface ice stability in Antarctica and Mars: in Lunar and planetary science conference XLI; papers presented to the Forty-first lunar and planetary science conference, Abstracts of Papers Submitted to the Lunar and Planetary Science Conference, 41, Paper 2511, illus., 17 ref., 2010. Meeting: Forty-first lunar and planetary science conference, March 1-5, 2010, Houston, TX. Accessed on July 29, 2011.

URL: http://www.lpi.usra.edu/meetings/lpsc2010/pdf/2511.pdf

12057179 Kraft, M. D. (Arizona State University, School of Earth and Space Exploration, Tempe, AZ); Rogers, A. D.; Fergason, R. L.; Michalski, J. R. and Sharp, T. G. Spectral and geomorphic evidence for chemical weathering in the icy plains of Acidalia Planitia, Mars: in Lunar and planetary science conference XLI; papers presented to the Forty-first lunar and planetary science conference, Abstracts of Papers Submitted to the Lunar and Planetary Science Conference, 41, Paper 2600, illus., 9 ref., 2010. Meeting: Forty-first lunar and planetary science conference, March 1-5, 2010, Houston, TX. Accessed on Aug. 4, 2011.

URL: http://www.lpi.usra.edu/meetings/lpsc2010/pdf/2600.pdf

12057100 Kreslavsky, M. A. (University of California at Santa Cruz, Department of Earth and Planetary Sciences, Santa Cruz, CA); Head, J. W.; Maine, A.; Gray, H. and Asphaug, E. North-south asymmetry in degradation craters of small impact craters at high latitudes on Mars; implications for recent climate change: in Lunar and planetary science conference XLI; papers presented to the Forty-first lunar and planetary science conference, Abstracts of Papers Submitted to the Lunar and Planetary Science Conference, 41, Paper 2560, illus., 15 ref., 2010. Meeting: Forty-first lunar and planetary science conference, March 1-5, 2010, Houston, TX. Accessed on July 29, 2011.

URL: http://www.lpi.usra.edu/meetings/lpsc2010/pdf/2560.pdf

12057143 Madden, A. S. (University of Oklahoma, School of Geology and Geophysics, Norman, OK); Madden, M. E. Elwood and Hamilton, V. E. Formation of Mars analog crystalline hematite from nanophase hematite under low temperature aqueous conditions: in Lunar and planetary science conference XLI; papers presented to the Forty-first lunar and planetary science conference, Abstracts of Papers Submitted to the Lunar and Planetary Science Conference, 41, Paper 1528, illus., 15 ref., 2010. Meeting: Forty-first lunar and planetary science conference, March 1-5, 2010, Houston, TX. Accessed on Aug. 2, 2011.

URL: http://www.lpi.usra.edu/meetings/lpsc2010/pdf/1528.pdf

12057160 Mitrofanov, I. (Russian Academy of Sciences, Institute for Space Research, Moscow, Russian Federation); Boynton, W.; Chin, G.; Golovin, D.; Evans, L.; Harshman, K.; Garvin, J.; Kozyrev, A.; Litvak, M.; McClanahan, T.; Malakhov, A.; Milikh, G.; Mokrousov, M.; Nandikotkur, G.; Nuzhdin, I.; Sanin, A.; Starr, R.; Sagdeev, R.; Shevchenko, V.; Shvetsov, V.; Tretyakov, V.; Trombka, J.; Varennikov, A. and Vostrukhin, A. LEND experiment onboard LRO; testing local areas with high concentrations of hydrogen at the lunar poles: in Lunar and planetary science conference XLI; papers presented to the Forty-first lunar and planetary science conference, Abstracts of Papers Submitted to the Lunar and Planetary Science Conference, 41, Paper 2250, 10 ref., 2010. Meeting: Forty-first lunar and planetary science conference, March 1-5, 2010, Houston, TX. Accessed on Aug. 2, 2011.

URL: http://www.lpi.usra.edu/meetings/lpsc2010/pdf/2250.pdf

12057097 Plaut, J. J. (California Institute of Technology, Jet Propulsion Laboratory, Pasadena, CA); Holt, J. W.; Head, J. W., III; Gim, Y.; Choudhary, P.; Baker, D. M. and Kress, A. Thick ice deposits in Deuteronilus Mensae, Mars; regional distribution from radar sounding: in Lunar and planetary science conference XLI; papers presented to the Forty-first lunar and planetary science conference, Abstracts of Papers Submitted to the Lunar and Planetary Science Conference, 41, Paper 2454, sketch map, 15 ref., 2010. Meeting: Forty-first lunar and planetary science conference, March 1-5, 2010, Houston, TX. Accessed on July 29, 2011.

URL: http://www.lpi.usra.edu/meetings/lpsc2010/pdf/2454.pdf

12057101 Séjourné, A. (Université Paris-Sud XI, Interactions et Dynamique des Environnements de Surface, Orsay, France); Costard, F.; Gargani, J.; Soare, R. J. and Marmo, C. The polygon junction pits as an evidence of a particularly ice-rich area in Utopia Planitia: in Lunar and planetary science conference XLI; papers presented to the Forty-first lunar and planetary science conference, Abstracts of Papers Submitted to the Lunar and Planetary Science Conference, 41, Paper 2113, illus., 15 ref., 2010. Meeting: Forty-first lunar and planetary science conference, March 1-5, 2010, Houston, TX. Accessed on July 29, 2011.

URL: http://www.lpi.usra.edu/meetings/lpsc2010/pdf/2113.pdf

12057263 Urschel, M. R. (Montana State University, Department of Microbiology, Bozeman, MT); Skidmore, M. L. and Geesey, G. Dissimilatory iron reduction in subzero brines [abstr.]: in Abstracts of the 20th annual V. M. Goldschmidt conference, Geochimica et Cosmochimica Acta, 74(12, Suppl. 1), p. A1066, 8 ref., 2010. Meeting: 20th annual V. M. Goldschmidt conference, June 13-18, 2010, Knoxville, TN.

URL: http://goldschmidt2010.org/abstracts/A-Z+Index.pdf

12057107 Vincendon, M. (Brown University, Department of Geological Sciences, Providence, RI); Mustard, J.; Forget, F.; Kreslavsky, M.; Spiga, A.; Murchie, S. and Bibring, J. P. Discovery of buried perennial ice at low latitudes on Mars: in Lunar and planetary science conference XLI; papers presented to the Forty-first lunar and planetary science conference, Abstracts of Papers Submitted to the Lunar and Planetary Science Conference, 41, Paper 1249, illus., 12 ref., 2010. Meeting: Forty-first lunar and planetary science conference, March 1-5, 2010, Houston, TX. Accessed on July 29, 2011.

URL: http://www.lpi.usra.edu/meetings/lpsc2010/pdf/1249.pdf

12057331 Wang, Fan (Purdue University, Department of Earth and Atmospheric Sciences, West Lafayette, IN); Ge Wensheng and Michalski, Greg. Role of water availability in source partitioning for desert nitrate; new evidence from mass-independent oxygen isotopic compositions [abstr.]: in Abstracts of the 20th annual V. M. Goldschmidt conference, Geochimica et Cosmochimica Acta, 74(12, Suppl. 1), p. A1100, 2010. Meeting: 20th annual V. M. Goldschmidt conference, June 13-18, 2010, Knoxville, TN.

URL: http://goldschmidt2010.org/abstracts/A-Z+Index.pdf

Back to the Top

12063162 Dyke, Art. National syntheses of environmental change: in Climate Change Geoscience Program; 2006-2011 program final report (Rencz, A. N., editor), Open-File Report - Geological Survey of Canada, Rep. No. 6879, p. 232-236, 30 ref., 2012. WWW. Accessed on June 27, 2012.

URL: ftp://ftp2.cits.rncan.gc.ca/pub/geott/ess_pubs/290/290156/of_6879.pdf

12063135 Dyke, Larry and Sladen, Wendy. Assessing the impact of climate change on permafrost based on field observations and modelling; Wapusk National Park case study; sub-activity; in-situ monitoring of permafrost dynamics in response to climate change: in Climate Change Geoscience Program; 2006-2011 program final report (Rencz, A. N., editor), Open-File Report - Geological Survey of Canada, Rep. No. 6879, p. 31-35, illus., 25 ref., 2012. WWW. Accessed on June 27, 2012.

URL: ftp://ftp2.cits.rncan.gc.ca/pub/geott/ess_pubs/290/290156/of_6879.pdf

12063153 Fernandes, Richard. Surface albedo feedback; observational constraints on climate models: in Climate Change Geoscience Program; 2006-2011 program final report (Rencz, A. N., editor), Open-File Report - Geological Survey of Canada, Rep. No. 6879, p. 146-156, illus., 15 ref., 2012. WWW. Accessed on June 27, 2012.

URL: ftp://ftp2.cits.rncan.gc.ca/pub/geott/ess_pubs/290/290156/of_6879.pdf

12063146 LeBlanc, A. M.; Oldenborger, G.; Sladen, Wendy; Mate, David; Allard, Michel; L'Hérault, E.; Doyon-Robitaille, J.; Carbonneau, A. S.; Gosselin, P.; Mathon-Dufour, V. and Falardeau-Marcoux, C. Assessing permafrost conditions and landscape hazards in support of climate change adaptation in Pangnirtung, Baffin Island, Nunavut: in Climate Change Geoscience Program; 2006-2011 program final report (Rencz, A. N., editor), Open-File Report - Geological Survey of Canada, Rep. No. 6879, p. 103-107, illus., 15 ref., 2012. WWW. Accessed on June 27, 2012.

URL: ftp://ftp2.cits.rncan.gc.ca/pub/geott/ess_pubs/290/290156/of_6879.pdf

12063131 Rencz, A. N., editor. Climate Change Geoscience Program; 2006-2011 program final report: Open-File Report - Geological Survey of Canada, Rep. No. 6879, 261 p., illus. incl. tables, 2012. WWW. Individual papers are cited separately. Accessed on June 27, 2012.

URL: ftp://ftp2.cits.rncan.gc.ca/pub/geott/ess_pubs/290/290156/of_6879.pdf

12063145 Smith, Rod; Irvine, Melanie; Bell, Trevor; Forbes, Don and Allard, Michel. Landscape hazard mapping in Clyde River and other Nunavut communities: in Climate Change Geoscience Program; 2006-2011 program final report (Rencz, A. N., editor), Open-File Report - Geological Survey of Canada, Rep. No. 6879, p. 100-102, illus., 9 ref., 2012. WWW. Accessed on June 27, 2012.

URL: ftp://ftp2.cits.rncan.gc.ca/pub/geott/ess_pubs/290/290156/of_6879.pdf

12063156 Smith, Sharon. State and evolution of Canadian permafrost; a component of cryosphere-climate observing, assessment and adaptation: in Climate Change Geoscience Program; 2006-2011 program final report (Rencz, A. N., editor), Open-File Report - Geological Survey of Canada, Rep. No. 6879, p. 172-173, illus., 2012. WWW. Accessed on June 27, 2012.

URL: ftp://ftp2.cits.rncan.gc.ca/pub/geott/ess_pubs/290/290156/of_6879.pdf

12063134 Zhang, Yu; Li, Junhua; Wang, Xiping; Chen, Wenjun; Sladen, Wendy; Dyke, Larry and Dredge, Lynda. Assessing the impacts of climate change on permafrost based on field observations and modelling/mapping; Wapusk National Park case study: in Climate Change Geoscience Program; 2006-2011 program final report (Rencz, A. N., editor), Open-File Report - Geological Survey of Canada, Rep. No. 6879, p. 27-30, illus., 14 ref., 2012. WWW. Accessed on June 27, 2012.

URL: ftp://ftp2.cits.rncan.gc.ca/pub/geott/ess_pubs/290/290156/of_6879.pdf

12063141 Zhang, Yu; Wang, Xiping; Chen, Wenjun; Li, Junhua; Sladen, Wendy; Dyke, Larry and Dredge, Lynda. Modeling and mapping permafrost and its response to climate change in Canada: in Climate Change Geoscience Program; 2006-2011 program final report (Rencz, A. N., editor), Open-File Report - Geological Survey of Canada, Rep. No. 6879, p. 64-70, illus., 32 ref., 2012. WWW. Accessed on June 27, 2012.

URL: ftp://ftp2.cits.rncan.gc.ca/pub/geott/ess_pubs/290/290156/of_6879.pdf

12062491 Ednie, M.; Chartrand, J. and Smith, S. L. Report on 2010 field activities and collection of ground thermal and active layer data in the Mackenzie Corridor completed under N.W.T. science licence #14686: Open-File Report - Geological Survey of Canada, Rep. No. 6932, 67 p., illus. incl. tables, 8 ref., 2011. WWW.

A summary of field activities conducted in 2010 in the Mackenzie Corridor under NWT Science License #14686 is presented. Ground thermal and active layer data acquired from permafrost monitoring sites visited in 2010 throughout the corridor are presented in graphical and tabular format. This report will be distributed to community organizations and stakeholders in the region to provide an update on field activities. The ground thermal and active layer data presented provide essential baseline information that can be utilized by stakeholders in the region and others for various purposes such as land management activities, regulatory processes and design of northern infrastructure.

DOI: 10.4095/288924

12062591 Issler, D. R.; Hu, K.; Lane, L. S. and Dietrich, J. R., compilers. GIS compilations of depth to overpressure, permafrost distribution, geothermal gradient, and regional geology, Beaufort-Mackenzie Basin, northern Canada: Open-File Report - Geological Survey of Canada, Rep. No. 5689, 1 disc, geologic maps, 1:1,000,000, 25 ref., 2011. compact disc, WWW.

Petroleum exploration well data on primary overpressure, permafrost distribution and thickness, and geothermal gradient were tabulated, quality-checked, contoured and placed on a base map of the regional bedrock geology and structure. Accompanying notes document the methodology and criteria for data quality ranking and give summary interpretations of the regional map patterns. Overpressure is largely confined to the northern delta and offshore areas and is the result of rapid deposition and deformation of the successive deltaic complexes comprising the basin. The depth to the top of overpressure varies by over 3 km. The first-order distribution of permafrost appears to be consistent with surface geological processes although basin thermal structure may have an important role. Typical sedimentary basin geothermal gradients (25-30°C/km) characterize much of the basin. Basin-margin areas show more variation, possibly related to basin architecture and/or data quality. The geological base map is updated from the regional map of Lane and Dietrich (1996).

DOI: 10.4095/289113

12062489 Smith, I. R.; Bednarski, J. M.; Deblonde, C.; Duk-Rodkin, A.; Huntley, D. and Kennedy, K. E. Potential granular aggregate resources in Northwest Territories and northern Yukon; an updated assessment integrating seismic shothole drillers' logs and surficial geology maps: Open-File Report - Geological Survey of Canada, Rep. No. 6849, 1 disc, illus. incl. tables, 2011. DVD, WWW.

This publication utilizes lithostratigraphic information provided by the revised and updated seismic shothole drillers' log database (GSC Open File 6833), and two other borehole databases, to identify potential granular aggregate resources. Lithostratigraphic records are interpreted and presented in a GIS at two depth intervals; upper 10 m (76 958 records) and total shothole depth (89 019 records), and are distinguished by location (surface vs. subsurface) and sediment type (gravel; gravel + sand; sand). This point-stratigraphic information is augmented by including granular aggregate-associated surficial geology map polygons (e.g., glaciofluvial deposits) from published and in progress maps throughout the Mackenzie corridor and northern Yukon. Where shothole records intersect map polygons, they can confirm the existence of aerially extensive surface granular aggregate deposits, and by extension provide a characterization of their sedimentology and thickness. Where shothole data occurs outside of granular aggregate-associated map polygons they can identify sites potentially obscured by vegetation or missed during surficial geology mapping. They also identify deposits in areas that have yet to be mapped.

DOI: 10.4095/288804

12062554 Wolfe, S. A.; Delaney, S. and Duchesne, C. An inventory of borrow pits and pond development between 1961 to 2005, Highway 3, Yellowknife region, Northwest Territories: Open-File Report - Geological Survey of Canada, Rep. No. 6948, 42 p. 1 disc, illus. incl. tables, 11 ref., 2011. compact disc, WWW.

This open file provides an inventory of historical borrow pit locations and subsequent pond development formed between 1961 and 2005 along the highway corridor between Behchoko and Yellowknife, Northwest Territories. The inventory and database were prepared to better understand potential relationships between highway performance and past terrain disturbance that could affect permafrost and geotechnical properties of sediments. The accompanying shapefile format data can be used in a GIS to place areas of borrow pits and recent ponds onto digital maps for referencing. In addition, files provided in KML format can also be used to locate these areas in Google Earth. The primary purpose of this inventory is to approximate the location and size of historical borrow pits and pond development in relation to highway infrastructure, as a basis for present and future reference to highway performance in this permafrost-affected terrain.

DOI: 10.4095/289032

Back to the Top

12059532 Allard, M.; Doyon, J.; Mathon-Dufour, V.; LeBlanc, A. M.; L'Hérault, E.; Mate, D.; Oldenborger, G. A. and Sladen, W. E. Surficial geology, Iqaluit, Nunavut: Geological Survey of Canada, Canadian Geoscience Map, Geological Survey of Canada, Ottawa, ON, Canada, Rep. No. 64, 1 disc or 1 sheet (French sum.), tables; surficial geology map, 1:15,000, 2 ref., 2012. ISBN: 978-1-100-19600-8 compact disc. Preliminary edition. Accessed on June 15, 2012.

This map illustrates the surficial geology of Iqaluit, Nunavut's capital city. Rather flat, sandy and gravelly glaciofluvial and glaciomarine sediments extend under the airport and its surroundings as well as in Apex. Precambrian bedrock with partial and uneven till cover is found under newly built areas on hilly terrain and plateaus. The area is underlain by continuous permafrost, which causes important technical challenges for the maintenance of infrastructure. A larger scale view of the airport sector emphasizes patterned ground features and the networks of frost cracks.

URL: http://apps1.gdr.nrcan.gc.ca/mirage/mirage_list_e.php?id=289503

12059533 Carbonneau, A. S.; Allard, M.; LeBlanc, A. M.; L'Hérault, E.; Mate, D.; Oldenborger, G. A.; Gosselin, P. and Sladen, W. E. Surficial geology and periglacial features, Pangnirtung, Nunavut: Geological Survey of Canada, Canadian Geoscience Map, Geological Survey of Canada, Ottawa, ON, Canada, Rep. No. 65, 1 disc or 1 sheet (French sum.), tables; surficial geology map, 1:5,000, 4 ref., 2012. ISBN: 978-1-100-19601-5 compact disc. Preliminary edition; accessed on June 15, 2012.

The map of surficial geology and periglacial features in Pangnirtung was done to help decision-makers, planners and engineers to better adapt the community to the impacts of climate change. The dominant surface unit on the map consists of colluvium deposits which are ice-rich sandy sediments deposited by overland-flow during snowmelt. Buried soils as old as 7080 cal BP were found imbedded in a colluvium layer. In the eastern sector of town, colluvium 1 to 4 metres thick covers till and a network of ice wedges. It also covers ice-rich marine silts and bedrock in the western sector. The central sector of town is occupied by a coarse, boulder-rich, Holocene outwash fan deposited by the Duval River. An alluvial terrace with boulders and some eroded channels were incised by the river in the fan. Bedrock and thick till deposits are found in the upper river valley and on the slopes of the fjord.

URL: http://apps1.gdr.nrcan.gc.ca/mirage/mirage_list_e.php?id=289504

12059534 Smith, I. R.; Irvine, M. L. and Bell, T. Periglacial and permafrost geology, Clyde River, Baffin Island, Nunavut: Geological Survey of Canada, Canadian Geoscience Map, Geological Survey of Canada, Ottawa, ON, Canada, Rep. No. 57, 1 disc or 1 sheet (French sum.), illus. incl. surficial geology map, 1:10,000, 2 ref., 2012. ISBN: 978-1-100-19593-3 compact disc. Preliminary edition. Accessed on June 15, 2012.

Geological mapping of periglacial landforms and permafrost features was undertaken as part of a community-scale assessment of how different aspects of the physical environment pose risks to existing and future infrastructure development, and how climate change may further alter infrastructure vulnerability. Airphoto and ground surveys were used to identify and map gelifluction lobes (Fig. 1), nivation hollows (Fig. 2), thermokarst depressions (Fig. 3), and ice wedges (Fig. 4). Additional insights were gained by drilling and analyzing 14 permafrost cores (0.19-2.83 m long; Irvine, 2011). Ice-rich, raised marine silty-sand deposits, containing saline permafrost, underlie much of the present town and airport. Surficial sediments in areas where new community developments are taking place, upslope from the coastal terraced regions, appear to potentially be much less affected by ground ice and saline permafrost, but are more subject to surface slope deformation, and the wind drifting and melting of snow in the lee sides of prominent recessional moraines.

URL: http://geopub.nrcan.gc.ca/moreinfo_e.php?id=289602

12059535 Smith, I. R.; Irvine, M. L. and Bell, T. Surficial geology, Clyde River, Baffin Island, Nunavut: Geological Survey of Canada, Canadian Geoscience Map, Geological Survey of Canada, Ottawa, ON, Canada, Rep. No. 58, 1 disc or 1 sheet (French sum.), surficial geology map, 1:10,000, 2 ref., 2012. ISBN: 978-1-100-19594-0 compact disc. Preliminary edition. Accessed on June 15, 2012.

Surficial and periglacial-permafrost geology mapping was undertaken in Clyde River, Nunavut, to assess how different aspects of the physical environment pose risks and hazards to existing and future infrastructure development, and how climate change may further alter infrastructure vulnerability. This research was undertaken as part of Natural Resources Canada's Climate Change Geoscience program and the Nunavut Climate Change Partnership. Most of Clyde River's town and airport are built atop thick, terraced, raised marine and glaciomarine sandy sediments that contain saline permafrost. These deposits support abundant ice wedges. Widespread thermokarst depressions indicate extensive massive and segregated ice content. Moraines, meltwater channels and ice-contact deposits record a fiord-ward and westward retreat of Late Wisconsinan glaciers. New community developments extend upslope from the coastal terraced regions on washed sandy till and moraine complexes. Granular aggregate materials suitable for infrastructure development are rare, although glaciofluvial terrace deposits offer potential.

URL: http://geopub.nrcan.gc.ca/moreinfo_e.php?id=289603

Back to the Top