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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

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That soil-moisture meter is a device used to record soil moisture in situ [16].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for vegetation (Keyword) returned 154 results for the whole karstbase:
Showing 136 to 150 of 154
Simulation of flow processes in a large scale karst system with an integrated catchment model (Mike She) Identification of relevant parameters influencing spring discharge, 2012, Doummar J. , Sauter M. , Geyer T.

In a complex environment such as karst systems, it is difficult to assess the relative contribution of the different components of the system to the hydrological system response, i.e. spring discharge. Not only is the saturated zone highly heterogeneous due to the presence of highly permeable conduits, but also the recharge processes. The latter are composed of rapid recharge components through shafts and solution channels and diffuse matrix infiltration, generating a highly complex, spatially and temporally variable input signal. The presented study reveals the importance of the compartments vegetation, soils, saturated zone and unsaturated zone. Therefore, the entire water cycle in the catchment area Gallusquelle spring (Southwest Germany) is modelled over a period of 10 years using the integrated hydrological modelling system Mike She by DHI (2007). Sensitivity analyses show that a few individual parameters, varied within physically plausible ranges, play an important role in reshaping the recessions and peaks of the recharge functions and consequently the spring discharge. Vegetation parameters especially the Leaf Area Index (LAI) and the root depth as well as empirical parameters in the relationship of Kristensen and Jensen highly influence evapotranspiration, transpiration to evaporation ratios and recharge respectively. In the unsaturated zone, the type of the soil (mainly the hydraulic conductivity at saturation in the water retention and hydraulic retention curves) has an effect on the infiltration/evapotranspiration and recharge functions. Additionally in the unsaturated karst, the saturated moisture content is considered as a highly indicative parameter as it significantly affects the peaks and recessions of the recharge curve. At the level of the saturated zone the hydraulic conductivity of the matrix and highly conductive zone representing the conduit are dominant parameters influencing the spring response. Other intermediate significant parameters appear to influence the characteristics of the spring response yet to a smaller extent, as for instance bypass and the parameters a in the Van Genuchten relation for soil moisture content curves.


Groundwater recharge and exploitative potential zone mapping using GIS and GOD techniques, 2012, Huang C. C. , Yeh H. F. , Lin H. I. , Lee S. T. , Hsu K. C. , Lee C. H.

Two-thirds of the total area of Taiwan is mountainous terrain, which is the main groundwater recharge source of the plains region. This study assesses groundwater recharge and exploitative potential zone in the central division of the mountain areas of Taiwan (the middle reaches of the Jhuoshuei River Basin). Basic information from remote sensing and a satellite phantom is collected to set up the basic data maps using elevation, Formosa-II images, the Normalized Difference Vegetation Index, drainage distribution, slope, aspect ratio, lineament distribution, and land cover. A geographical information system is used to integrate five contributing factors, namely lithology, land cover/land use, drainage, slope, and lineaments. The criteria for the recharge potential assessment are established to demarcate the potential groundwater recharge zone. Finally, the GOD rating system is adopted to evaluate the potential exploitation zone. Three main parameters are considered: the groundwater occurrence, the lithology of the overlying layers, and the depth to groundwater. The results show that the middle reaches of the Chenyuland River have large potential exploitation zones due to its high rainfall recharge capacity. Regions west of the Jhuoshuei River and the downstream regions of the Chingshui River are medium potential exploitation zones because of their high infiltration rates and shallow groundwater levels


Hydroecogeochemical effects of an epikarst ecosystem: case study of the Nongla Landiantang Spring catchment, 2012, Shen L. , Deng X. , Jiang Z. , Li T.

A typical small-scale epikarst ecosystemusually consists of an epikarst zone, soil and vegetation. In this study, to determine the hydro-eco-geochemical effects of an epikarst ecosystem in subtropical humid area, the samples of vegetation, soil, soil microbes, rainfall, throughfall, stem flow, soil water and epikarst springs of Nongla Village, Mashan County, Guangxi in China were collected and analyzed. The research results have shown in the epikarst ecosystem, the conductivity, temporary hardness and total carbon increased continuously in hydro-ecochemical cycle; the vegetation–soil system conducted the transformation and transference of carbon in hydro-ecochemical cycle; the vegetation layer was the major source for organic carbon, while the soil layer was of the important chemical field for the conversion of organic/inorganic carbon and HCO3 –, which would affect the epikarst dynamical system; for most ions, the vegetation layer and shallow soil layer presented more leaching effect than absorption, in contrast, the deep soil layer behaved oppositely. The vegetation layer and shallow soil layer leached ions, and deep soil layer absorbed them. With the plant community presenting in a positive succession, the epikarst ecosystem trended to be stabilized gradually, which made the hydro-eco-geochemical effects to be adjusted and controlled more effectively


Delineating Protection Areas for Caves Using Contamination Vulnerability Mapping Techniques: The Case of Herreras Cave, Asturias, Spain, 2012, Marn A. I. , Andrea B. , Jimnezsnchez M. , Dominguezcuesta M. J. , Melndezasensio

 

Diverse approaches are adopted for cave protection. One approach is delineating protection areas with regard to their vulnerability to contamination. This paper reports the main results obtained from the delineation of a protection zone for Herrerı´as Cave, declared of Cultural Interest by the Asturias Regional Government, based on assessing its vulnerability to contamination. The cave is situated in a complex karst hydrogeologic environment in which groundwater flows from southwest to northeast, following the bedrock structure. A stream flows inside the cave, emerging in a spring located to the northeast of the system. Karst recharge occurs by direct infiltration of rainfall over limestone outcrops, concentrated infiltration of surface runoff in the watershed draining the cave, and deferred infiltration of water from alluvial beds drained by influent streams. The soil and vegetation covers are natural in the majority of the test site, but land uses in the watershed, including scattered farming, stock breeding, quarrying, and tourist use, are changing the natural characteristics and increasing the cave’s vulnerability to contamination. The procedure followed for delineating protection zones is based on the method COP+K that is specifically designed for vulnerability mapping of groundwater springs in carbonate aquifers. To cover the hydrological basin included in the cave’s catchment area, the protection zones established includes two different areas, the hydrogeological catchment basin and adjacent land that contributes runoff. Different degrees of protection in the zones have been proposed to make human activity compatible with conservation of the cave, and our results show remarkable differences from the protection zone previously proposed for the same area.


Importance of karst Sinkholes in Preserving Relict, Mountain, and Wet-Woodland Plant Species under Sub-Mediterranean Climate: A Case Study from Souther Hungary, 2012, Btori Z. , Krmczi L. , Erds L. , Zalatnai M. , Csiky J.

 

Species composition and the vegetation pattern of the understory were investigated in different sized solution sinkholes in a woodland area of the Mecsek Mountains (southern Hungary). Vegetation data together with topographic variables were collected along transects to reveal the vegetation patterns on the slopes, and a species list was compiled for each sinkhole. The results indicate that the vegetation pattern significantly correlates with sinkhole size. In smaller sinkholes, vegetation does not change substantially along the transects; in larger sinkholes, however, vegetation inversion is pronounced. We also found that sinkhole size clearly influences the number of vascular plant species, in accordance with the well-known relationship between species number and area. In the forest landscape, many medium-sized and large sinkholes have developed into excellent refuge areas for glacial relicts, mountain, and wet-woodland plant species.


New data on the dolines of Velebit Mountain: An evaluation of their sedimentary archive potential in the reconstruction of landscape evolution , 2012, Ballut Christle, Faivre Sanja

The first approach to the relationships between societies and physical environments on Velebit Mountain shows narrow correlations between spatial distribution of dolines, soil formation, hydric resources, vegetation and land occupation. In 2002, sediment cores have been obtained from different dolines of Velebit Mountain to evaluate the potential of their sedimentary archives in order to reconstruct the landscape history. On the littoral slopes and on the top parts of the mountain, the dolines were difficult to dig due to the presence of rocks in depth. Nevertheless, the cores have been sampled and soil analyses have been made (physical and chemical analyses: colour, grain size, pH, CaCO3, C, N, P, K, Mg, CEC). No dating materials were found. The first results attest to rather homogeneous pedologic processes in each area studied (Kamenica, Stinica, Baške Oštarije and Bilensko Mirevo), but they also indicate colluvial contributions. These contributions differ from one doline to another according to their location and morphology. Dolines reveal themselves to be not very good traps, as the representative nature of their sedimentary archives could be very local. However, the best profile has been obtained at Bilensko Mirevo, which shows a change in the soil nutrient content from an impoverishment in its middle part toward an increase of the soil nutrients in recent parts. Those environmental changes could not be precisely dated, but could be correlated with the 17th to 20th century phase of strong human impact on the Velebit environment and with the rural depopulation observed since the second half of the 20th century.


Analysis of the capabilities of low frequency ground penetrating radar for cavities detection in rough terrain conditions: The case of Divača cave, Slovenia , 2012, Gosar, Andrej

High frequency ground penetrating radar (GPR) is usually applied for cavities detection in a shallow subsurface of karst areas to prevent geotechnical hazards. For specific projects, such as tunnel construction, it is important to detect also larger voids at medium depth range. However, dimensions of classical rigid low frequency antennas seriously limit their applicability in a rough terrain with dense vegetation commonly encountered in a karst. In this study recently developed 50 MHz antennas designed in a tube form were tested to detect cave gallery at the depth between 12 m and 60 m. The Divaca cave was selected because of a wide range of depths under the surface, possibility of unknown galleries in the vicinity and a rough terrain surface typical for Slovenian karst. Seven GPR profiles were measured across the main gallery of the cave and additional four profiles NE of the cave entrance where no galleries are known. Different acquisition and processing parameters were analysed together with the data resolution issues. The main gallery of the cave was clearly imaged in the part where the roof of the gallery is located at the depth from 10 m to 30 m. The width of the open space is mainly around 10 m. Applied system was not able to detect the gallery in the part where it is located deeper than 40 m, but several shallower cavities were discovered which were unknown before. The most important result is that the profiles acquired NE of the cave entrance revealed very clearly the existence of an unknown gallery which is located at the depth between 15 m and 22 m and represents the continuation of the Divaca cave. Access to this gallery is blocked by the sediment fill in the entrance shaft of the cave. The results of the study are important also for future infrastructure projects which will involve construction of tunnels through karstified limestone and for speleological investigations to direct the research efforts.


New insights into the carbon isotope composition of speleothem calcite: An assessment from surface to subsurface, 2012, Meyer, Kyle William

The purpose of this study was to provide new insights into the interpretation of speleothem (cave calcite deposit) δ13C values. We studied two caves in central Texas, which have been actively monitored for over 12 years. We compared δ13C values of soil CO2 (δ13Cs), cave drip water (δ13CDIC), and modern cave calcite (δ13Ccc). Measured average δ13C values of soil CO2 were -13.9 ± 1.4‰ under mixed, shallowly-rooted C3-C4 grasses and were -18.3 ± 0.7‰ under deeply-rooted ashe juniper trees (C3). The δ13CDIC value of minimally-degassed drip water in Natural Bridge Caverns was -10.7 ± 0.3‰. The carbon isotope composition of CO2 in equilibrium with this measured drip water is -18.1 ± 0.3‰. The agreement between juniper soil CO2 and drip water (within ~0.2‰) suggests that the δ13C value of drip water (δ13CDIC) that initially enters the cave is controlled by deeply-rooted plants and may be minimally influenced by host-rock dissolution and/or prior calcite precipitation (PCP). At Inner Space Caverns, δ13CDIC values varied with vegetation above the drip site, distance from the cave entrance, and distance along in-cave flow paths. Whereas CO2 derived from deeply-rooted plants defines the baseline for drip water δ13CDIC entering the caves, kinetic effects associated with the degassing of CO2 and simultaneous precipitation of calcite account for seasonal variability in δ13CDIC and δ13Ccc. We documented increases in δ13CDIC at a rate of up to 0.47‰/hour during the season of peak degassing (winter), suggesting that δ13CDIC variations may be controlled by total elapsed time of CO2 degassing from drip water (Ttotal). We also observed seasonal shifts in the δ13C values of modern calcite grown on glass substrates that are correlated with shifts in drip water δ13CDIC values and drip-rate. Therefore, we suggest that increased aridity at the surface above a given cave results in, slower drip-rates, higher Ttotal, and therefore higher δ13CDIC values. We propose that large variability (>2‰) in speleothem δ13Ccc values dominantly reflect major vegetation changes, and/or increasing Ttotal by slowing drip-rates. Based on these findings, variability in speleothem carbon isotope records may serve as a proxy for paleoaridity and/or paleovegetation change.


New insights into the carbon isotope composition of speleothem calcite : an assessment from surface to subsurface, 2012, Meyer, Kyle William

The purpose of this study was to provide new insights into the interpretation of speleothem (cave calcite deposit) δ13C values. We studied two caves in central Texas, which have been actively monitored for over 12 years. We compared δ13C values of soil CO2 (δ13Cs), cave drip water (δ13CDIC), and modern cave calcite (δ13Ccc). Measured average δ13C values of soil CO2 were -13.9 ± 1.4‰ under mixed, shallowly-rooted C3-C4 grasses and were -18.3 ± 0.7‰ under deeply-rooted ashe juniper trees (C3). The δ13CDIC value of minimally-degassed drip water in Natural Bridge Caverns was -10.7 ± 0.3‰. The carbon isotope composition of CO2 in equilibrium with this measured drip water is -18.1 ± 0.3‰. The agreement between juniper soil CO2 and drip water (within ~0.2‰) suggests that the δ13C value of drip water (δ13CDIC) that initially enters the cave is controlled by deeply-rooted plants and may be minimally influenced by host-rock dissolution and/or prior calcite precipitation (PCP). At Inner Space Caverns, δ13CDIC values varied with vegetation above the drip site, distance from the cave entrance, and distance along in-cave flow paths. Whereas CO2 derived from deeply-rooted plants defines the baseline for drip water δ13CDIC entering the caves, kinetic effects associated with the degassing of CO2 and simultaneous precipitation of calcite account for seasonal variability in δ13CDIC and δ13Ccc. We documented increases in δ13CDIC at a rate of up to 0.47‰/hour during the season of peak degassing (winter), suggesting that δ13CDIC variations may be controlled by total elapsed time of CO2 degassing from drip water (Ttotal). We also observed seasonal shifts in the δ13C values of modern calcite grown on glass substrates that are correlated with shifts in drip water δ13CDIC values and drip-rate. Therefore, we suggest that increased aridity at the surface above a given cave results in, slower drip-rates, higher Ttotal, and therefore higher δ13CDIC values. We propose that large variability (>2‰) in speleothem δ13Ccc values dominantly reflect major vegetation changes, and/or increasing Ttotal by slowing drip-rates. Based on these findings, variability in speleothem carbon isotope records may serve as a proxy for paleoaridity and/or paleovegetation change.


A holistic approach to groundwater protection and ecosystem services in karst terrains, 2012, Goldscheider, Nico

A holistic conceptual approach to groundwater and natural resources protection, surface and subsurface biodiversity conservation and ecosystem services in karst terrains is presented. Karst landscapes and aquifers consist of carbonate rock in which a part of the fractures has been enlarged by chemical dissolution. They are characterised by unique geomorphological and hydrogeological features, such as rapid infiltration of rainwater, lack of surface waters, and turbulent flow in a network of fractures, conduits and caves. Karst terrains contain valuable but vulnerable resources, such as water, soil and vegetation, and they provide a great variety of habitats to many species, both at the surface and underground, including many rare and endemic species. Karst systems deliver various ecosystem services and act as natural sinks for carbon dioxide (CO2) thus helping to mitigate climate change. It is demonstrated that all these resources and ecosystem services cannot be considered in an isolated way but are intensely interconnected. Because of these complex feedback mechanisms, impacts on isolated elements of the karst ecosystem can have unexpected impacts on other elements or even on the entire ecosystem. Therefore, the protection of natural resources, biodiversity and ecosystem services in karst requires a holistic approach


Major stone forest, litomorphogenesis and development of typical shilin (Yunnan, China), 2012, Knez M. , Slabe T. , Liu H.

Major stone forest excellently reveals most characteristics of the formation of the various stone forests. The relatively thick stratification and evenly composed rock clearly display the development of stone forests from subsoil karren. This is evident from the shape of individual parts of the stone forest and the shape and rock relief of pillars that comprise the forest. It is the most typical example of development of karren from subsoil to rain and vegetation exposed stone forest. With it we can compare stone forests shaped on different rock and geomorphological and hydrological conditions. Type of rock is clearly reflected in the intensity of corrosion and erosion and with it in the formation and morphological appearance of individual stone pillars and larger blocks of rock. The rock relief on the pillars in stone forests reveals the interwoven traces of the original shaping of the rock below soil and sediment, of the lowering of the level of soil and sediment, and of the younger but distinct transformation of pillars by rainwater, which naturally dominates on the tops. The exceptional character and picturesqueness of this karst phenomenon is the reason for the successful development of the stone forest as an international tourist attraction that was deservedly placed on the UNESCO world heritage list.


Major stone forest, litomorphogenesis and development of typical shilin (Yunnan, China), 2012, Knez Martin, Slabe Tadej, Liu Hong

Major stone forest excellently reveals most characteristics of the formation of the various stone forests. The relatively thick stratification and evenly composed rock clearly display the development of stone forests from subsoil karren. This is evident from the shape of individual parts of the stone forest and the shape and rock relief of pillars that comprise the forest. It is the most typical example of development of karren from subsoil to rain and vegetation exposed stone forest. With it we can compare stone forests shaped on different rock and geomorphological and hydrological conditions. Type of rock is clearly reflected in the intensity of corrosion and erosion and with it in the formation and morphological appearance of individual stone pillars and larger blocks of rock. The rock relief on the pillars in stone forests reveals the interwoven traces of the original shaping of the rock below soil and sediment, of the lowering of the level of soil and sediment, and of the younger but distinct transformation of pillars by rainwater, which naturally dominates on the tops. The exceptional character and picturesqueness of this karst phenomenon is the reason for the successful developmentof the stone forest as an international tourist attraction that was deservedly placed on the UNESCO world heritage list.


A holistic approach to groundwater protection and ecosystem services in karst terrains, 2012, Goldscheider, Nico

A holistic conceptual approach to groundwater and natural resources protection, surface and subsurface biodiversity conservation and ecosystem services in karst terrains is presented. Karst landscapes and aquifers consist of carbonate rock in which a part of the fractures has been enlarged by chemical dissolution. They are characterised by unique geomorphological and hydrogeological features, such as rapid infiltration of rainwater, lack of surface waters, and turbulent flow in a network of fractures, conduits and caves. Karst terrains contain valuable but vulnerable resources, such as water, soil and vegetation, and they provide a great variety of habitats to many species, both at the surface and underground, including many rare and endemic species. Karst systems deliver various ecosystem services and act as natural sinks for carbon dioxide (CO2) thus helping to mitigate climate change. It is demonstrated that all these resources and ecosystem services cannot be considered in an isolated way but are intensely interconnected. Because of these complex feedback mechanisms, impacts on isolated elements of the karst ecosystem can have unexpected impacts on other elements or even on the entire ecosystem. Therefore, the protection of natural resources, biodiversity and ecosystem services in karst requires a holistic approach.


Thermal springs and hypogenic karstification processes in flow system context, 2013, Mdlsző, Nyi Judit, Erő, Ss Anita

Uplifted unconfined and adjoining confined continental carbonate aquifers contain thermal water with marginal thermal springs as decisive discharge features connected to tectonic contact between the unconfined and confined part of the system. These areas are characterised by positive thermal anomaly, particular mineral precipitates and phre-atophyte vegetation. These systems are important not only as sources of thermal water but the confined parts of the system can serve as hydrocarbon reservoirs, moreover Mississippi Valley Type (MVT) ore deposits can also be connected to such environ-ments. Hypogenic speleogenesis can be active at such marginal discharge zones of groundwater due to the direct corrosive effect of deep originated fluids. These different processes are known from the literature however their relationships have not been revealed comprehensively. The application of regional groundwater flow system theory and evaluation can give a chance to understand the common origin of these different processes, which is moving groundwater. The Buda Thermal Karst offers an exception-al natural laboratory where groundwater flow systems and their effect on rock matrix and the environment can be examined and proved directly. Moreover as new discharge phenomenon a karst corrosive biofilm was recognized here. The presentation displays the most important conclusions which can be generalized for areas with similar hydro-geological settings. The research is supported by the NK 101356 OTKA research grant


KARST DEVELOPMENT IN THE GLACIATED AND PERMAFROSTREGIONS OF THE NORTHWEST TERRITORIES, CANADA, 2013, Ford Derek

 

The Northwest Territories of Canada are ~1.2 million km2 in area and appear to contain a greater extent and diversity of karst landforms than has been described in any other region of the Arctic or sub-Arctic. The Mackenzie River drains most of the area. West of the River, the Mackenzie Mountains contain spectacular highland karsts such as Nahanni (Lat. 62° N) and Canol Road (Lat. 65° N) that the author has described at previous International Speleological Congresses. This paper summarizes samples of the mountain and lowland karst between Lats. 64–67° N that are located east of the River. The Franklin Mountains there are east-facing cuestas created by over-thrusting from the west. Maximum elevations are ~1,000 m a.s.l., diminishing eastwards where the cuestas are replaced by undeformed plateaus of dolomite at 300–400 m asl that overlook Great Bear Lake. In contrast to the Mackenzie Mountains (which are generally higher) all of this terrain was covered repeatedly by Laurentide Continental glacier ice flowing from the east and southeast. The thickness of the last ice sheet was >1,200 m. It receded c.10,000 years ago. Today permafrost is mapped as “widespread but discontinuous” below 350 m a.s.l. throughout the region, and “continuous” above that elevation. The vegetation is mixed taiga and wetlands at lower elevations, becoming tundra higher up. Access is via Norman Wells (population 1,200), a river port at 65° 37’N, 126° 48’W, 67 m a.s.l.: its mean annual temperature is -6.4 °C (January mean -20 °C, July +14 °C) and average precipitation is ~330 mm.y-1, 40 % falling as snow. In the eastern extremities a glacial spillway divides the largest dolomite plateau into “Mahony Dome” and “Tunago Dome”. The former (~800 km2) has a central alvar draining peripherally into lakes with overflow sinkholes, turloughs, dessicated turloughs, and stream sinks, all developed post-glacially in regular karst hydrologic sequences. Tunago Dome is similar in extent but was reduced to scablands by a sub-glacial mega-flood from the Great Bear basin; it is a mixture of remnant mesas with epikarst, and wetlands with turloughs in flood scours. Both domes are largely holokarstic, draining chiefly to springs at 160–180 m a.s.l. in the spillway. The eastern limit of overthrusting is marked by narrow ridges created by late-glacial hydration of anhydrite at shallow depth in interbedded dolostones and sulphate rocks. Individual ridges are up to 60 km long, 500–1,000 m wide, 50–250 m in height. They impound Lac Belot (300 km2), Tunago Lake (120 km2) and many lesser lakes, all of which are drained underground through them. In the main overthrust structures, the Norman Range (Franklin Mountains) is oriented parallel with the direction of Laurentide ice flow. It displays strongly scoured morphology with elongate sinkholes on its carbonate benches. In contrast, the Bear Rock Range is oriented across the ice flow, has multiple cuestas, is deeply furrowed and holokarstic but preserves pinnacle karst on higher ground due to karst-induced polar thermal (frozen-down) conditions at the glacier base there.


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