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Enviroscan Ukrainian Institute of Speleology and Karstology


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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. ...

Did you know?

That flattener is a cave passage, which though wide, is so low that movement is only possible in a prone position [10]. see also crawl.?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms


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KarstBase a bibliography database in karst and cave science.

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 canada (Keyword) returned 129 results for the whole karstbase:
Showing 121 to 129 of 129
Quaternary cave faunas of Canada: a review of the vertebrate remains, 2011,
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Harington, C. R.

Highlights of ice-age vertebrate faunas from Canadian caves are presented in geographic order (east to west). They include four each from Quebec and Ontario; three from Alberta; one from Yukon; and ten from British Columbia. Localities, vertebrate species represented, radiocarbon ages, and paleoenvironmental evidence are mentioned where available, as well as pertinent references. Of these caves, perhaps Bluefish Caves, Yukon, are most significant, because they contain evidence for the earliest people in North America. Tables provide lists of species and radiocarbon ages from each site


Castleguard Cave, Canada, 2012,
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Ford, Derek

Castleguard Cave is the longest cave system currently known in Canada (21 km) and the foremost example anywhere of a cavern extending underneath a modern glacier. It displays many striking features of interactions between glaciers and karst aquifers, a complex modern climate, rich mineralization, and a troglobitic fauna that has possibly survived one or more ice ages beneath deep ice cover in the heart of the Rocky Mountains.


Effective porosity of a carbonate aquifer with bacterial contamination: Walkerton, Ontario, Canada, 2012,
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Worthington S. R. H. , Smart C. C. , Ruland W.

Preferential flow through solutionally enlarged fractures can be a significant influence on travel times and source area definition in carbonate aquifers. However, it has proven challenging to step beyond a conceptual model to implementing, parameterizing and testing an appropriate numerical model of preferential flow. Here both porous medium and preferential flow models are developed with respect to a deadly contamination of the municipal groundwater supply at Walkerton, Ontario, Canada. The preferential flow model is based on simple orthogonal fracture aperture and spacing. The models are parameterized from bore hole, gamma, flow and video logs resulting in a two order of magnitude lower effective porosity for the preferential flow model. The observed hydraulic conductivity and effective porosity are used to predict groundwater travel times using a porous medium model. These model predictions are compared to a number of independent estimates of effective porosity, including three forced gradient tracer tests. The results show that the effective porosity and hydraulic conductivity values closely match the preferential flow predictions for an equivalent fracture network of _10 m spacing of 1 mm fractures. Three tracer tests resulted in groundwater velocities of hundreds of meters per day, as predicted when an effective porosity of 0.05% was used in the groundwater model. These velocities are consistent with a compilation of 185 tracer test velocities from regional Paleozoic carbonate aquifers. The implication is that carbonate aquifers in southern Ontario are characterized by relatively low-volume dissolutionally enlarged fracture networks that dominate flow and transport. The porous matrix has large storage capacity, but contributes little to transport. Numerical models based on much higher porosities risk significantly underestimating capture zones in such aquifers. The hydraulic conductivity – effective porosity prediction framework provides a general analytical frame work for a preferential flow carbonate aquifer. Not only is the framework readily parameterized from borehole observations, but also it can be implemented in a conventional porous medium model, and critically tested using simple tracer tests.


Cure from the cave: volcanic cave actinomycetes and their potential in drug discovery, 2013,
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Cheeptham N. , Sadoway T. , Rule D. , Watson K. , Moote P. , Soliman L. C. , Azad N. , Donkor K. K. , Horne D.

Volcanic caves have been little studied for their potential as sources of novel microbial species and bioactive compounds with new scaffolds. We present the first study of volcanic cave microbiology from Canada and suggest that this habitat has great potential for the isolation of novel bioactive substances. Sample locations were plotted on a contour map that was compiled in ArcView 3.2. Over 400 bacterial isolates were obtained from the Helmcken Falls cave in Wells Gray Provincial Park, British Columbia. From our preliminary screen, of 400 isolates tested, 1% showed activity against extended spectrum ß-lactamase E. coli, 1.75% against Escherichia coli, 2.25% against Acinetobacter baumannii, and 26.50% against Klebsiella pneumoniae. In addition, 10.25% showed activity against Micrococcus luteus, 2% against methicillin resistant Staphylococcus aureus, 9.25% against Mycobacterium smegmatis, 6.25% Pseudomonas aeruginosa and 7.5% against Candida albicans. Chemical and physical characteristics of three rock wall samples were studied using scanning electron microscopy and f lame atomic absorption spectrometry. Calcium (Ca), iron (Fe), and aluminum (Al) were the most abundant components while magnesium (Mg), sodium (Na), arsenic (As), lead (Pb), chromium (Cr), and barium (Ba) were second most abundant with cadmium (Cd) and potassium (K) were the least abundant in our samples. Scanning electron microscopy (SEM) showed the presence of microscopic life forms in all three rock wall samples. 16S rRNA gene sequencing of 82 isolates revealed that 65 (79.3%) of the strains belong to the Streptomyces genus and 5 (6.1%) were members of Bacillus, Pseudomonas, Nocardia and Erwinia genera. Interestingly, twelve (14.6%) of the 16S rRNA sequences showed similarity to unidentif ied ribosomal RNA sequences in the library databases, the sequences of these isolates need to be further investigated using the EzTaxon-e database (http://eztaxon-e. ezbiocloud.net/) to determine whether or not these are novel species. Nevertheless, this suggests the possibility that they could be unstudied or rare bacteria. The Helmcken Falls cave microbiome possesses a great diversity of microbes with the potential for studies of novel microbial interactions and the isolation of new types of antimicrobial agents.


The effects of UV light on the antimicrobial activities of cave actinomycetes, 2013,
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Rule Devon, Cheeptham Naowarat

The goal of this study was to determine whether actinomycetes isolated from a volcanic cave in western Canada could produce novel antimicrobial compounds against six multidrug- resistant pathogens when exposed to UV light. One hundred and seventy-six actinomycete strains isolated from Helmcken Falls Cave, Wells Gray Provincial Park, BC, were screened against six pathogens using the “plug assay” in UV light and no light conditions. Of the 176 strains tested, 100 or 57% of the cave actinomycete strains had antimicrobial activities against the pathogens in 124 different instances: 35 instances when exposed to UV and no light, 30 when exposed to UV light, and 59 instances when exposed to no light. The metabolites of six actinomycete strains also lost their antimicrobial activities when exposed to UV light. While the metabolites produced by these strains have yet to be determined, exposure to lighted environments may either deactivate or enhance the antimicrobial activities of cave actinomycete strains. This study represents a confirmation that cave actinomycetes are potential sources of novel antimicrobial compounds and also is the first report of the enhancement of antimicrobial activities of some cave bacteria by exposure to UV light. Further investigation of the role of UV light with respect to activation/deactivation of antimicrobial activities of cave actinomycetes is required.


The Grosmont: the worlds largest unconventional oil reservoir hosted in polyphase-polygenetic karst, 2013,
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Machel Hans G. , Borrero Mary Luz, Dembicki Eugene, Huebscher Harald4

The Upper Devonian Grosmont platform in Alberta, Canada, is the world’s largest heavy oil reservoir hosted in carbonates, with 400-500 billion barrels of IOIP at an average depth of about 250 – 400 m. Advanced thermal recovery technologies, such as SAGD and electrical in-situ retorting, much higher world market prices for oil and certain political pressures have led to a flurry of activity in the Grosmont since 2006.
The sedimentary stratigraphy of the Grosmont reservoir consists of six stacked car-bonate units interbedded with marls and some evaporites. The latter two originally acted as aquitards during diagenesis but are breached or missing in parts of the area today. Dolomitization by density-driven reflux was the first pervasive diagenetic pro-cess. A dense fracture network was created in three or four phases. Most fractures probably originated from collapse following subsurface salt dissolution and/or from Laramide tectonics far to the west, whereby pulsed crustal loading in the fold-and-thrust belt created a dynamic forebulge in the Grosmont region via multiple pulses of basin-wide crustal flexing, each followed by relaxation. The fracture network probably was reactivated and/or expanded by glacial loading and post-glacial isostatic rebound in the Pleistocene and Holocene, respectively.
The region experienced three or four prolonged periods of epigene karstification, alt-hough there is tangible evidence for only two of them in the Grosmont platform. The first of these episodes was a ‘warm epigene karstification’ during the Jurassic - Creta-ceous, and the second was/is a ‘cold epigene karstification’ that started sometime in the Cenozoic and is continuing to this day. In addition, there is circumstantial evidence for hypogene ‘karstification’ (= dissolution) throughout much of the geologic history of the Grosmont since the Late Devonian. Karstification was accompanied and/or by fol-lowed by extensive hydrocarbon biodegradation.


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


LITTLE LIMESTONE LAKE: A BEAUTIFUL MARL LAKE IN MANITOBA, CANADA, 2013,
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Ford Derek

 

Marl lakes are those accumulating fine-grained bottom sediments that include at least 15% CaCO3. They are found worldwide. The most visually attractive, however, have higher proportions of CaCO3, with crystallites precipitating in the water to give it a rich and opaque duck-egg blue colouration. From the literature, such lakes are largely limited to recently glaciated carbonate rock terrains. Most are also shallow, with much or all of the water column being in the photic zone. Little Limestone Lake, (Lat. 53°47’N, Long. 99°19’W in the province of Manitoba) is the finest example that the author has seen. It stands out sharply from neighbouring lakes in summertime colour satellite imagery due to the intensity and uniformity of its colour. The lake occupies a shallow glacial trough scoured in a plain of flat-lying cyclothem dolomites. It is ~12 km long, 1–5 km wide, rarely >7 m deep. Including bordering wetlands, it occupies ~45 % of the area of an elongated, narrow topographic basin. Recharge is through impoverished boreal forest with little soil cover; it discharges chiefly as springs and seeps along and below the shore. Mean annual temperature is ~0 °C, and precipitation is ~475 mm.y1. Previous studies of springs in the surrounding region showed ground waters to be simple bicarbonate composition, with TDS = 230–300 mg.l-1 (Ca 40–60 mg.l-1, Mg 30–40 mg.l-1). Grab sampling at 27 sites throughout the lake found the waters de-gassed to 125–135 mg.l-1, placing them in the mid-range of one hundred marl lakes investigated in more detail in the British Isles. Ca was reduced to 25–30 mg.l-1, while Mg was stable at 30–40 mg.l-1. There were 2–3 mg.l-1 of free CO3 in two fully analysed samples, indicating that plankton photosynthesis might be occurring. However, samples of the bottom marl were predominantly inorganic in their composition. Little Limestone Lake is visually spectacular because it is almost entirely groundwater-fed, with a ratio of recharge area to lake area that is low. It has no large, chemically equilibrated, surface streams entering it. In contrast, the dozens of nearby lakes (similar, larger or smaller in size) are regularly flushed by channelled storm water and, although they also produce some carbonate marl, cannot maintain high densities of crystallites in suspension. Little Limestone Lake was placed under legislated protection as a provincial park in June 2011.


Incipient vertical traction carpets within collapsed sinkhole fills, 2014,
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Small vertically oriented traction carpets are reported from the collapsed sandy fills of 100 m deep Devonian limestone sinkholes underlying the Lower Cretaceous Athabasca oil sands deposit in north-eastern Alberta, Western Canada. Dissolution of 100 m of underlying halite salt beds caused cataclysmic collapse of the sinkhole floors and water saturated sinkhole sand fills to descend very rapidly. Turbulent currents flushed upper sinkhole fills of friable sandstone blocks and disaggregated sand and quartz pebble for tens of metres. Laminar deposits with inverse grading accumulated as many as six to eight curvilinear entrained pebble streaks, 10 to 30 cm long, vertically impinged against the sides of descending collapse blocks. These deposits were initiated as vertically oriented early stage traction carpets that interlocked fine sand grains and inversely graded overlying pebbles entrained below the dilute overlying turbulent flows. Vortexes that flushed these sinkhole fills and induced these depositional processes may have lasted only seconds before the very rapid descents abruptly halted. Some of the fabrics were suspended vertically in-place and preserved from unlocking and obliteration. These small fabrics provide insight into the instability and ephemeral character of the transition from strong gravity-driven grain falls to very early stages of traction carpet formation. These short-lived deposits of very thin sand layers resulted from sufficient incipient frictional freezing that grain interlocking overcame, however briefly, the strong gravity drives of the vertical falls that would have otherwise dispersed grains and obliterated any organized fabric patterns. Tenuous frictionally locked grains were also suspended at the centres of hyperbolic grain fall flows that briefly developed between turbulent flow eddies, some of which were fortuitously preserved. Some of these suspended grain locking zones passed downward onto the relatively more stable surfaces of the rapidly descending block surfaces. The morphogenesis of these early stage traction carpets differ from more fully developed deposits elsewhere because of their short-lived transport, dynamic instability and vertical orientation.


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