Ground Ice Bodies Research Articles

Assessing the impact of ground ice degradation on high mountain lake environments (Lago Nero catchment, Swiss Alps)

In high mountain hydrosystems, glacial meltwater composition is potentially affected by the degradation of alpine permafrost terrains and ground ice bodies releasing atmospheric pollutants that have been stored in permafrost terrains for several decades. In this study we investigate the potential local permafrost distribution as well as the physical and chemical ground water characteristics of the periglacial environments of the Lago Nero (“Black Lake”) catchment, a high alpine basin located in the Southern Swiss Alps. Our approach combines in situ geological and geomorphological mapping, potential permafrost distribution modelling, a thermal monitoring of ground surface temperatures and the study of the meltwater chemistry of an intact rock glacier (active or inactive rock glacier, i.e. containing ice) and several perennial ice patches. The comparison of elemental concentrations between the periglacial terrains and the Lago Nero outflow unveiled the presence of atmospheric chemicals in the meltwater. Considering the temporal concordance between the recorded peak of sulphur deposition between 1965 and 1980 and the last identified period of positive glacier mass balance occurred in the region (1961–1985), we argue that the enhanced melting of ground ice related to the recent severe warming is nowadays releasing “legacy” pollutants that have been stored in the cryosphere for several decades.

Пластовые залежи подземного льда в свете данных об оледенении Сибири

Пластовые залежи подземного льда в свете данных об оледенении Сибири

PECULIARITIES OF DYNAMICS OF THERMOABRASIONAL COASTS OF THE BAYDARATSKAYA BAY (KARA SEA) TODAY

The article is dedicated to the peculiarities of the dynamics of thermoabrasional coasts of the Kara Sea in the area of the gas main pipeline “Bovanenkovo-Ukhta” crossing of the Baydaratskaya Bay. The coasts in Yamal and Ural key sites differ signifi cantly both in wind wave conditions and in criolithologic structure. The study was based on the results of the coastal retreat fi eld monitoring, carried on since 1988. Spatial and temporal variability of the thermoabrasional coasts dynamics have been estimated. The effect of wind-wave and thermal factors on the temporal variability of the coastal dynamics has been determined. We have found out that average coastal retreat rates in natural conditions vary from 0.3 and 1.2 m/year at the Yamal key site and from 0.5 to 2.4 m/year at the Ural key site. Spatial variability of coastal retreat rates in the Baydaratskaya Bay is determined by the geomorphological structure of the shore. It is more considerable in the Ural key site than in the Yamal key site because of more complex geocryological structure and the presence of ground ice bodies. Temporal variability of coastal retreat rates of the Baydaratskaya Bay in natural conditions is mainly determined by the wind-wave factor at the Yamal key site and by the combination of wind-wave and thermal factors at the Ural key site. It is better expressed at the Ural key site than at the Yamal key site, along with spatial variability. In 2009–2012, the main factor determining the coastal dynamics at both Yamal and Ural coasts was the technogenic factor.

Isotopic composition on ground ice in Western Yamal (Marre-Sale)

The profile of Quaternary sediments near Marre-Salle polar station, Western Yamal Peninsula, has large bodies of tabular ground ice. This profile is considered strata-typical and critical in understanding of paleogeographic conditions of the Arctic in Pleistocene-Holocene. However, interpretation of the profile is under discussion. It consists of two distinct strata: upper layer of 10–15 m thick represented by continental sediments and lower one with a thickness of more than 100 m represented by marine sediments. Lower layer of saline marine clays has lenses of tabular ground ice (more than 20 m thick), the bases of which are below the sea level. Upper continental layer is characterized by syngenetic ice-wedges of different generations. Samples were collected from ice-wedges and tabular ground ice for chemical and isotope analysis. The results of the analysis allow to reconstruct paleogeographic conditions of the sedimentation and freezing of Quaternary sediments. Heavy stable isotope content and relationship between oxygen and hydrogen isotopes show that the ice bodies in the lower layer were formed in-situ within the ground. In the upper layer, heavier isotope content found in younger ice-wedges relative to the old-generation wedges. Formation of massive syngenetic Upper-Pleistocene ice-wedges occurred in conditions of colder winter temperatures than at present. Syngenetic Holocene wedges were formed after Holocene Optimum under winter conditions similar to present. Younger ice wedges formed smaller polygons, were smaller and often were developing in the locations of the degraded old wedges. Results of the isotope analysis of various types of ground ice near Marre-Sale allow reconstructing changes of marine sedimentation to continental one around Kargino time (MIS 3) and changes in climatic conditions in Arctic in Late Pleistocene and Holocene.

Air temperature changes and their impact on permafrost ecosystems in eastern Siberia

Significant increasing of mean annual air temperatures, freezing index and thawing index - have exerted a considerable impact on the state of permafrost landscapes and ecosystems in Eastern Siberia on the last few decades. Many animals and plants have shifted their ranges and this may be the precursor of northward shifts of the landscape zones. Landscapes that contain ground ice bodies in the underlying permafrost are especially sensitive to climate warming. Increase of mean annual air temperature for 2-3°C over the last three decades has resulted an increase in ground temperature by 0.4-1.3°C in the upper part of permafrost, which in turn has led intensification of negative cryogenic processes. Previous year’s measurements of greenhouses gases emission in the Middle Taiga forest of central Yakutia were found to show high values and spatial variability. The wet meadow soils and shallow lakes have highest methane fluxes, almost comparable with emissions from tropical peatlands. Permafrost ecosystems respond to global warming quite rapidly. This makes the study of their changes somewhat easier, but still requires meticulous attention to observations, research, and analysis of the processes under way.

Geomicrobiology and occluded O 2–CO 2–Ar gas analyses provide evidence of microbial respiration in ancient terrestrial ground ice

The study of ancient massive ground ice and sediment-rich ice bodies not only allows an understanding of the stability of permafrost, but also offers the possibility to understand the long-term preservation and viability of microbes within these ice bodies. Although microorganisms have been identified in ancient bodies of ground ice and permafrost, there still is a lack of convincing evidence that the microbes were metabolically active within the ice. In this study, we combine geomicrobiology methods with the measurements of occluded gasses in four ancient massive ground ice bodies to provide evidence of microbial respiration. In our samples, abundant cold-adapted heterotroph microorganisms were identified using culture-dependent and -independent methods. The occluded gas measurements, with low δ(O 2/Ar) (less than − 21.4%) and δ 13C CO 2 (as low as − 25.2‰) values and high δ 18O O 2 (up to + 16.3‰) values are suggestive of in situ consumption of O 2 by heterotrophic psychrophilic bacteria living within the ice matrix. Overall, the multi-disciplinary approach provides a strong set of tools from which to infer metabolic activity within bodies of ground ice. The analysis of δ(O 2/Ar), δ 18O O 2 and δ 13C CO 2 from occluded gasses in ice are strong isotope biosignatures that could allow detecting evidence of life on other planetary icy bodies such as Mars.

Isotope characterisation of ground ice in northern Canada

AbstractThis paper reviews isotopic research on the characterisation and identification of various types of ground ice throughout the Canadian Arctic, including buried glacier ice, massive segregated ice, segregated ice lenses and offshore ice‐rich permafrost, as well as ice related to other cold‐region phenomena such as ice wedges, icings (aufeis), frost blisters and pingos. The formational age of ground ice bodies ranges from recent (seasonal ice in the active layer) to tens of thousands of years, when the region experienced widespread continental‐scale glaciation. Modern ice lenses generally have 18O/16O ratios of ‐18 to ‐22‰, while modern ice wedges usually range from ‐22 to ‐25‰. δ18O values as high as ‐14‰ are representative of the Hypsithermal period (4000 to 8000 years BP), while glacial‐age ice has been measured with 18O/16O ratios as low as ‐36‰. Buried glacier ice often preserves climatic variations from the time of snow deposition. Other massive ground ice bodies contain isotopic signatures (18O and 2H) that indicate variable fractionation of the isotopes during freezing of the source water at stationary freezing fronts in either open or closed systems. Placing the ice bodies into a time frame can be accomplished either through age dating of the enclosing sediments and encased organics, or by direct dating of the ice utilising tritium (3H) for relatively young ice and radiocarbon (14C) analysis of contained gas bubbles for older ice. Copyright © 2011 John Wiley & Sons, Ltd.

Origin and characteristics of massive ground ice on Herschel Island (western Canadian Arctic) as revealed by stable water isotope and Hydrochemical signatures

AbstractHerschel Island in the southern Beaufort Sea is a push moraine at the northwestern‐most limit of the Laurentide Ice Sheet. Stable water isotope (δ18O, δD) and hydrochemical studies were applied to two tabular massive ground ice bodies to unravel their genetic origin. Buried glacier ice or basal regelation ice was encountered beneath an ice‐rich diamicton with strong glaciotectonic deformation structures. The massive ice isotopic composition was highly depleted in heavy isotopes (mean δ18O: −33‰; mean δD: −258‰), suggesting full‐glacial conditions during ice formation. Other massive ice of unknown origin with a very large δ18O range (from −39 to −21‰) was found adjacent to large, striated boulders. A clear freezing slope was present with progressive depletion in heavy isotopes towards the centre of the ice body. Fractionation must have taken place during closed‐system freezing, possibly of a glacial meltwater pond. Both massive ground ice bodies exhibited a mixed ion composition suggestive of terrestrial waters with a marine influence. Hydrochemical signatures resemble the Herschel Island sediments that are derived from near‐shore marine deposits upthrust by the Laurentide ice. A prolonged contact between water feeding the ice bodies and the surrounding sediment is therefore inferred. Copyright © 2011 John Wiley & Sons, Ltd.

Stability of massive ground ice bodies in University Valley, McMurdo Dry Valleys of Antarctica: Using stable O–H isotope as tracers of sublimation in hyper-arid regions

To date, studies of the stability of subsurface ice in the McMurdo Dry Valleys of Antarctica have been mainly based on climate-based vapor diffusion models. In University Valley (1800m), a small glacier is found at the base of the head of the valley, and adjacent to the glacier, a buried body of massive ice was uncovered beneath 20–40cm of loose cryotic sediments and sandstone boulders. This study assesses the origin and stability of the buried body of massive ice by measuring the geochemistry and stable O–H isotope composition of the ice and applies a sublimation and molecular diffusion model that accounts for the observed trends. The results indicate that the buried massive ice body represents an extension of the adjacent glacier that was buried by a rock avalanche during a cold climate period. The contrasting δ18O profiles and regression slope values between the uppermost 6cm of the buried massive ice (upward convex δ18O profile and SD-18O=5.1) and that below it (progressive increase in δ18O and SD-18O=6.4) suggest independent post-depositional processes affected the isotope composition of the ice. The upward convex δ18O profile in the uppermost 6cm is consistent with the ice undergoing sublimation. Using a sublimation and molecular diffusion model, and assuming that diffusion occurred through solid ice, the sublimation rate needed to fit the measured δ18O profile is 0.2 ⋅ 10−3mm yr−1, a value that is more similar to net ice removal rates derived from 3He data from cobbles in Beacon Valley till (7.0 ⋅ 10−3mm yr−1) than sublimation rates computed based on current climate (0.1–0.2mm yr−1). We suggest that the climate-based sublimation rates are offset due to potential ice recharge mechanisms or to missing parameters, particularly the nature and thermo-physical properties of the overlying sediments (i.e., temperature, humidity, pore structure and ice content, grain size).

Late Quaternary paleoenvironments and growth of intrusive ice in eastern Beringia (Eagle River valley, northern Yukon, Canada)

In this study, the sediments exposed in a fluvial terrace and in the headwall of a thaw slump in the Eagle River valley, northern Yukon, provide new data about the timing of flooding of glacial Lake Old Crow, the formation of massive ground ice bodies, and the vegetation and the fauna in eastern Beringia during the late Quaternary. The stratigraphy and radiocarbon ages establish the following chronology of events: (1) a gravel fluvial terrace was deposited by an overflow from glacial Lake Hughes into glacial Lake Old Crow; (2) a carbonate silty clay was deposited during the maximum level of glacial Lake Old Crow at 15 120 14C year BP; (3) permafrost and large intrusive ice bodies aggraded through the glaciolacustrine and underlying sediments following the drainage of glacial Lake Old Crow from the site; (4) at 11 290 14C year BP, a shrub–sedge tundra colonized an uneven surface deformed by the bodies of ground ice; (5) a thaw lake drained at 6730 14C year BP after flooding the site; (6) during the early Holocene and from the previous major event onwards, material from the slope nearby the site buried the previous organic and inorganic sediment and the ice bodies; and (7) a bison (Bison) vertebra with conspicuous cut marks was dated to 12 210 ± 70 14C year BP. The age from the bison bone is amongst the most recent of the late Pleistocene bison specimens yet found in eastern Beringia.

Molar gas ratios of air entrapped in ice: A new tool to determine the origin of relict massive ground ice bodies in permafrost

The molar ratios of atmospheric gases change during dissolution in water due to differences in their relative solubilities. We exploited this characteristic to develop a tool to clarify the origin of ice formations in permafrost regions. Extracted from ice, molar gas ratios can distinguish buried glacier ice from intrasedimental ground ice formed by freezing groundwaters. An extraction line was built to isolate gases from ice by melting and trapping with liquid He, followed by analysis of N 2, O 2,, Ar, 18O O2 and 15N N2, by continuous flow mass spectrometry. The method was tested using glacier ice, aufeis ice (river icing) and intrasedimental ground ice from sites in the Canadian Arctic. O 2/Ar and N 2/Ar ratios clearly distinguish between atmospheric gas in glacial ice and gases from intrasedimental ground ice, which are exsolved from freezing water. δ 15N N2 and δ 18O O2 in glacier ice, aufeis ice and intrasedimental ground ice do not show clear distinguishing trends as they are affected by various physical processes during formation such as gravitational settling, excess air addition, mixing with snow pack, and respiration.

Ice foot, freeze-thaw of sediments, and platform erosion in a subarctic microtidal environment, Manitounuk Strait, northern Quebec, Canada

The role of shore ice and freeze-thaw processes in intertidal sediments was studied along the inner shoreline of Manitounuk Strait through a series of drillings through the ice foot and numerous observations at all seasons. Mechanical processes such as drift-ice scouring and clast transport play only a minimal part in the observed changes. The thermal behaviour of the ice foot and the control it exerts on surface and groundwater flow throughout winter are the dominant factors of the shoreline dynamics. As the ice foot freezes to the surface of the tidal flat, a freezing front penetrates to depths of 3 m in the underlying sediments, which consist of postglacial Tyrrell Sea clays. This induces the formation of segregation ice which destroys the structure of the clays and leads to their thaw liquefaction in early summer. As this deep penetration of frost beneath the ice foot also impedes winter groundwater and surface-water flow, forced seepage and springs form icings (naleds), frost blisters, and lens-shaped bodies of intrusive ground ice at the upper margin of the tidal zone. The melting of all this ground ice induces settlement, microcliff collapse, and mud flows. The Manitounuk tidal zone, rather than being a typical tidal flat, is an erosional platform that is cut in soft Quaternary sediments and is being graded to tidal regime. Freeze-thaw processes controlled by the presence and thermal behaviour of the ice foot are the principal agents of platform destruction while waves and tidal currents are the transport agents that remove the sediments from the tidal zone. Platform erosion is presently the main source for sediment deposition in the shallow waters of Manitounuk Strait. Such a series of coastal periglacial processes may play an important role in other subarctic coastal settings. They also play an important ecological role, as they prevent the colonization of the coastal zone by mollusks and restrict the extent of coastal marshes.

The origin of the ground ice in the Malyk‐Sien basin, Northeastern USSR

Abstract The Quaternary sequence filling the Malyk‐Sien basin includes beds of diaraicton sediments and ground ice bodies. Some specialists consider the ice bodies enclosed in these diamicton deposits to be fossil glacier ice and the icy sediments to be till. But the observed bedding (oblique in some places), traces of displacement, signs of displacements in mud flows, and inclusions of wood and peat provide evidence of a deluvial‐solifluction origin for these deposits. The sorting and bedding of sand‐and‐clay intercalations in the ice, as well as inclusions of organic material exclude the idea that they were formed by moving ice. Rather, they are evidence that they originated under the influence of moving water. The “folds”; sometimes occurring in the sand‐and‐clay intercalations represent the tracks of tiny trickles of water, depositing fine material during the ocurse of ice formation. The data on the chemical composition reveal that it is similar in composition to the surface and ground water of the ar...

Climate, Hydrology and Vegetation Patterns Hot Weather Creek, Ellesmere Island, Arctic Canada

Recent studies at Hot Weather Creek, Ellesmere Island document the climate and vegetation of a major part of the intermontane zone of Ellesmere Island. Summer temperatures in this region are much higher than would be expected for its 80° N location. This enables a variety of arctic species with more moderate temperature tolerances to thrive. The dense and diverse tundra and wetland vegetation in parts of the region, however, does not conform to polar desert or semidesert vegetation expected from the meager amount of precipitation (< 70 mm per year) recorded there. Comparisons between differing biological and geomorphological responses to the summer climatic regimes of 1988 and 1989 suggest a two source supply of moisture to the active layer in summer. Supplementary source of water, from the melting of massive ground ice bodies provides water from the base of the active layer, during the hot, dry summer of 1988. During the wet summer of 1989, a more conventional nival regime was in operation. These two potential sources of moisture in summer provide a fail-safe delivery system to vegetation in areas underlain by massive ground ice, and permit a richer vegetation growth than climate alone could.

Observations on buried glacier ice and massive segregated ice, western arctic coast, Canada

AbstractThe two main theories for the origin of the thick bodies of massive ground ice known to exist in the Western Canadian Arctic are (1) segregation‐injection and (2) buried glacier ice. Because buried glacier ice may contain significant quantities of stratified debris and may have experienced thawing and refreezing (regelation) on several occasions, it may be very difficult to distinguish between massive segregated ice and buried basal glacier ice. By use of cryostratigraphic and cryotextural (petrofabric) observations, massive ground ice bodies observed in the Sandhills Moraine, southern Banks Island, and the southern Eskimo Lakes region, Pleistocene Mackenzie Delta, are both interpreted as basal glacier ice. Other massive ground ice bodies which have been examined in the Western Canadian Arctic are best explained in terms of segregation‐injection.

Former glaciation and permafrost in Asia

Abstract The article examines the problem of the relationship between ice caps and permafrost on the basis of the Pleistocene history of Asia. It is demonstrated that during the cryogenic epochs, and specifically during the period 30,000–16,000 years, B.P., permafrost covered a greater areal extent than ice sheets. The questions of the origin of major bodies of ground ice in the plains of Northern Eurasia, and of the cryogenic conditions during early stages of the geological history of the Earth are discussed. Cryological conditions prevailing on other planets in the solar system are also briefly discussed.

Nature and origin of ground ice, Sandhills Moraine, southwest Banks Island, Western Canadian Arctic

AbstractThe Sandhills Moraine is a Late Wisconsinan lateral moraine complex on southwest Banks Island. The occurrence of ice‐ablation landforms, ground ice slumps, kettle lakes and catastrophic lake drainage in winter suggests the presence of substantial bodies of massive ground ice. The distinctive hummocky topography of the Sandhills Moraine is thought to reflect partial melt‐out of this ice. Stratigraphic observations indicate that the ice is overlain irregularly and unconformably by glacigenic sediments, notably pebbly clay (till) and/or sandy gravels (outwash), while the ice itself possesses numerous and variable mineral inclusions, faults and foliations. Petrofabric analyses indicate a strongly preferred orientation to the ice crystals. It is suggested that these characteristics are best explained if the ground ice is interpreted as relict glacier ice.

Peculiarities of the morphology of glacial dislocations on the Kara sea coast

Abstract The author describes tight, asymmetrical minor folds in well‐bedded sands, loams and clays exposed by thermal abrasion of ice‐rich sediments on the west coast of Yamal and the north coast of Yugor Peninsula. The folds are commonly underlain by massive bodies of ground ice. The author postulates that the folds are the product of a southward flow of ice within an ice‐sheet sitting on the Kara Shelf, over unconsolidated sediments which were already frozen.

Underground ice in Western Siberia: Origin and geological significance

Abstract The origin of massive bodies of ground ice in Western Siberia is reconsidered on the basis of new publications and of the authors’ field observations at the Ledyanaya Gora site. The available evidence suggests that the largest ice bodies are of glacier origin and are buried remnants of the Kara Ice Sheet. The influence of permafrost accounts for their preservation. The volume of ground ice contained in these ice bodies amounts to about 10,000 km3, which is 67% of the total volume of present‐day glaciers in the USSR. This type of ground ice ought to be the subject of special glaciological studies. Similar remnants of former ice sheets preserved in permafrost have been discovered in the north of Central Siberia, Alaska, and Canada. All these regions also contain ground ice bodies of segregation, injection, and wedge origin. The occurrence of ground ice and especially of massive, tabular ice bodies creates a range of growing environmental problems with regard to economic development in Western Siber...

Ground-ice investigations, Klondike District, Yukon Territory

Massive bodies of ground ice, 2.0–4.0 m thick, are regularly exposed in small placer mining operations in the Klondike District, Yukon. At Mayes claim, Hunker Creek, the ice is underlain by 2.0–3.0 m of creek gravels and overlain by 10.0–15.0 m of organic-rich and ice-rich muck deposits. The crystallographic and petrographic characteristics of the ice and its stratigraphic occurrence suggest that the ice body either had a segregation origin or was a residual snowbank subsequently buried by muck deposits and recrystallized.