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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 ion is an element or compound that has gained or lost an electron so that it is no longer neutral electrically and now carries a charge [6].?

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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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Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
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
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Your search for north-america (Keyword) returned 8 results for the whole karstbase:
On the Geology of the Western States of North America, 0000, Owen David Dale,
The remarks here submitted will be confined chiefly to that part of the Western States of North America watered by the rivers Ohio, Wabash, Illinois, Rock, Wisconsin, Cumberland and Tennessee, lying between the 35th and 43rd degree of N. latitude and the 81st and 91st of W. longitude. The district includes the states of Illinois, Indiana, Ohio, Kentucky, Tennessee, and the Du Buque and Mineral Point districts of Iowa and Wisconsin. This territory occupies an area of about half a million of square miles, but its geological features are remarkably uniform, belonging, with a few partial exceptions, to the periods of the bituminous coal and carboniferous limestone as found in Europe, and the Silurian rocks as described by Sir R. Murchison; the exceptions are the superficial deposits which occasionally cover up these from view over considerable tracts, and these must either be referred to the age of gigantic mammalia and formations of a much newer date, or belong to a marl and greensand found in the western district of Tennessee, probably a portion of the greensand and other members of the cretaceous group. A general idea of the geological formations of the whole tract may be obtained from the annexed diagram. ... This 250-word extract was created in the absence of an abstract

Palaeoenvironment of lateritic bauxites with vertical and lateral differentiation, 1983, Valeton Ida,
Formation of lateritic bauxites of the type described in this paper occurs world-wide in Cretaceous and Tertiary coastal plains. The bauxites form elongate belts, sometimes hundreds of kilometres long, parallel to Lower Tertiary shorelines in India and South America and their distribution is not related to a particular mineralogical composition of the parent rock. The lateral movement of the major elements Al, Si, Fe, Ti is dependent on a high level and flow of groundwater. Varying efficiency of subsurface drainage produces lateral facies variations. Interfingering of marine and continental facies indicate a sea-land transition zone where the type of sediments also varies with minor tectonic movements or sea-level changes. A typical sediment association is found in India, Africa, South and North America. It consists of (i) red beds rich in detrital and dissolved material of reworked laterites, (ii) lacustrine sediments and hypersaline precipitates, (iii) lignites intercalated with marine clays, layers of siderite, pyrite, marcasite and jarosite, and (iv) marine chemical sediments rich in oolitic iron ores or glauconite. A model is developed to account for element distributions in lateritic bauxites in terms of groundwater levels and flow. Finally it is shown that many high-level bauxites are formed in coastal plains and that they are subsequently uplifted to their present altitude

THE KASKASKIA PALEOKARST OF THE NORTHERN ROCKY-MOUNTAINS AND BLACK-HILLS, NORTHWESTERN USA, 1995, Palmer A. N. , Palmer M. V. ,
The Kaskaskia paleokarst, part of the Mississippian-Pennsylvanian unconformity in North America, is typified by sinkholes, fissures, and dissolution caves at and near the top of the Kaskaskia Sequence (Madison Limestone and equivalents) and is covered by basal Absaroka siliciclastics (Chesterian to Morrowan). In the Rocky Mountains and Black Hills of the northwestern U. S. A. it postdates earlier features produced by sulfate-carbonate interactions, including breccias, dissolution voids, bedrock alteration, and mineralization. Both the paleokarst and earlier features have been intersected by post-Laramide caves. Ore deposits, aquifers, and petroleum reservoirs in the region are also concentrated along both the paleokarst horizons and earlier sulfate-related features. Each phase of karst modified and preferentially followed the zones of porosity and structural weakness left by earlier phases, producing an interrelated complex of now-relict features. All should be considered together to explain the present aspect of the paleokarst

CYCLOSTRATIGRAPHY OF MIDDLE DEVONIAN CARBONATES OF THE EASTERN GREAT-BASIN, 1995, Elrick M,
Middle Devonian carbonates (250-430 m thick) of the eastern Great Basin were deposited along a low energy, westward-thickening, distally steepened ramp. Four third-order sequences can be correlated across the ramp-to-basin transition and are composed of meter-scale, upward-shallowing carbonate cycles (or parasequences). Peritidal cycles (shallow subtidal facies capped by tidal-flat laminites) constitute 90% of all measured cycles and are present across the entire ramp. The peritidal cycles are regressive- and transgressive-prone (upward-deepening followed by upward-shallowing facies trends). Approximately 80% of the peritidal cycle caps show evidence of prolonged subaerial exposure including sediment-filled dissolution cavities, horizontal to vertical desiccation cracks, rubble and karst breccias, and pedogenic alteration; locally these features are present down to 2 m below the cycle caps. Subtidal cycles (capped by shallow subtidal facies) are present along the middle-outer ramp and ramp margin and indicate incomplete shallowing. submerged subtidal cycles (64% of all subtidal cycles) are composed of deeper subtidal facies overlain by shallow subtidal facies. Exposed subtidal cycles are composed of deeper subtidal facies overlain by shallow subtidal facies that are capped by features indicative of prolonged subaerial exposure (dissolution cavities and brecciation). Average peritidal and subtidal cycle durations are between approximately 50 and 130 k.y. (fourth- to fifth-order). The combined evidence of abundant exposure-capped peritidal and subtidal cycles, transgressive-prone cycles, and subtidal cycles correlative with updip peritidal cycles indicates that the cycles formed in response to fourth- to fifth-order, glacio-eustatic sea-level oscillations. Sea-level oscillations of relatively low magnitude (< 10 m) are suggested by the abundance of peritidal cycles, the lack of widely varying, water-depth-dependent facies within individual cycles, and the presence of noncyclic stratigraphic intervals within intrashelf-basin, slope, and basin facies. Noncyclic intervals represent missed subtidal beats when the seafloor lay too deep to record the effects of the short-term sea-level oscillations. Exposure surfaces at the tops of peritidal and subtidal cycles represent one, or more likely several, missed sea-level oscillations when the platform lay above fluctuating sea level, but the amplitude of fourth- to fifth-order sea-level oscillation(s) were not high enough to flood the ramp. The large number of missed beats (exposure-capped cycles), specifically in Sequences 2 and 4, results in Fischer plots that show poorly developed rising and falling limbs (subdued wave-like patterns); consequently the Fischer plots: are of limited use as a correlation tool for these particular depositional sequences. The abundance of missed beats also explains why Milankovitch-type cycle ratios (similar to 5:1 or similar to 4:1) are not observed and why such ratios would not be expected along many peritidal-cycle-dominated carbonate platforms

Geochronology of late Pleistocene to Holocene speleothemsfrom central Texas: Implications for regional paleoclimate, 2001, Musgrove Marylynn, Banner Jay L. , Mack Larry E. , Combs Deanna M. , James Eric W. , Cheng Hai, Edwards R. Lawrence,
A detailed chronology for four stalagmites from three central Texas caves separated by as much as 130 km provides a 71 000-yr record of temporal changes in hydrology and climate. Mass spectrometric 238U-230Th and 235U-231Pa analyses have yielded 53 ages. The accuracy of the ages and the closed- system behavior of the speleothems are indicated by interlaboratory comparisons, concordance of 230Th and 231Pa ages, and the result that all ages are in correct stratigraphic order. Over the past 71 000 yr, the stalagmites have similar growth histories with alternating periods of relatively rapid and slow growth. The growth rates vary over more than two orders of magnitude, and there were three periods of rapid growth: 71-60 ka, 39-33 ka, and 24-12 ka. These growth-rate shifts correspond in part with global glacial-interglacial climatic shifts. Paleontological evidence indicates that around the Last Glacial Maximum (20 ka), climate in central Texas was cooler and wetter than at present. This wetter interval corresponds with the most recent period of increased growth rates in the speleothems, which is consistent with conditions necessary for speleothem growth. The temporal shift in wetness has been proposed to result from a southward deflection of the jet steam due to the presence of a continental ice sheet in central North America. This mechanism also may have governed the two earlier intervals of fast growth in the speleothems (and inferred wetter climate). Ice volumes were lower and temperatures in central North America were higher during these two earlier glacial intervals than during the Last Glacial Maximum, however. The potential effects of temporal variations in precession of Earth's orbit on regional effective moisture may provide an additional mechanism for increased effective moisture coincident with the observed intervals of increased speleothem growth. The stalagmites all exhibit a large drop in growth rate between 15 and 12 ka, and they show very slow growth up to the present, consistent with drier climate during the Holocene. These results illustrate that speleothem growth rates can reflect the regional response of a hydrologic system to regional and global climate variability

Basin fluid flow, base-metal sulphide mineralization and the development of dolomite petroleum reservoirs, 2004, Gregg Jay M. ,
Saline basinal fluids, at temperatures from 60 to 250 {degrees}C, have affected almost every sedimentary basin in the world including rocks from Palaeoproterozoic to Cenozoic age. These fluids commonly precipitate base-metal sulphides (pyrite, sphalerite, galena, etc.) and associated minerals (barite, fluorite, calcite, dolomite, etc.) ranging in volume from trace amounts to large economic ore deposits. Such deposits are commonly referred to as Mississippi Valley-type (MVT) after the large Palaeozoic deposits of this kind found in the Mississippi Valley of North America. They are primarily hosted by platform carbonates, typically dolomite, and are usually associated with hydrocarbons. Dolomites not affected by mineralizing fluids commonly display micron- to decimicron-size planar textures, and have well-developed micro- and mesoporosity networks dominated by intercrystal and vug porosity. However, these and other carbonate rocks affected by basinal fluids may undergo massive geochemical and textural alteration. This occurs even when the affected rocks are distal from the main loci of sulphide mineralization. Alteration includes: dolomitization of limestone; neomorphic recrystallization of existing dolomite; and precipitation at intervals of large volumes of open-space-filling dolomite, calcite and quartz cements alternating with dissolution. Dolomitization of limestone and/or neomorphic recrystallization of dolomite, at elevated temperatures, commonly results in centimicron and larger size crystals, and development of nonplanar textures that increase pore-throat tortuosity. Open-space-filling dolomite, calcite and quartz cementation causes a dramatic reduction of porosity and blockage of pore throats. Periods of carbonate dissolution, proximal to intense sulphide mineralization, result in the development of large-scale macroporosity such as breccias that are commonly superimposed on karst and tectonic fractures. Exposure to mineralizing basinal fluids substantially alters porosity and permeability distribution, and thus the potential reservoir properties of the dolomite. The resulting reservoir may have little resemblance to its precursor. Understanding the epigenetic history of a dolomite is critical, therefore, as this will ultimately affect its development strategy and production history

Late Pleistocene paleoclimate in the Black Hills of South Dakota from isotope records in speleothems, 2004, Serefiddin Feride, Schwarcz Henry P. , Ford Derek C. , Baldwin Steve,
Two coeval speleothems from the Black Hills are used to investigate [delta]18O and [delta]13C variations within Reed's Cave and reconstruct climate during the Wisconsin glacial period from 82[punctuation space]000 to 24[punctuation space]000 years ago. Variation in growth rates between the two speleothems reveals a strong control of hydrology and surface vegetation on isotopic variability and response of [delta]18O to climate. High-resolution [delta]18O and [delta]13C data show that local environmental conditions can produce an offset of [delta]18O values of up to 4[per mille sign] in coeval speleothems but still reveal important climate events. The transition from warmer to cooler periods results in an increase in [delta]18O of calcite ([delta]18Oct) in sample RC2 while in sample RC20, another equilibrium deposit coeval to part of the RC2 record, [delta]18Oct is offset from RC2 by between 0 and -3.5[per mille sign], and shows much higher frequency isotopic variation. Speleothem RC2 records interglacial/glacial transitions and interstadial events that are also present in speleothems from North America and Europe. Spectral analysis of the [delta]18Oct records for both speleothems reveals periodicity at 1000 to 2000 years, similar to millennial scale variability seen in the North Atlantic sediments and the Greenland ice cores

Hierarchical analysis of switchgrass morphology, 2005, Boe A, Casler Md,
Switchgrass (Panicum virgatum L.) has potential as a biomass crop in North America. Our objective was to determine effects of cultivar and location on morphological traits that influence biomass in switchgrass. Six cultivars with origins from 37 degrees N, 88 degrees W (Cave-In-Rock and Shawnee) to 46 degrees N, 100 degrees W (Dacotah) were evaluated in 1-yr-old swards at Bristol and South Shore, SD; in 3-yr-old swards at Brookings, SD, and Arlington, WI; and in 15-yr-old swards at Pierre, SD, for biomass; tillers m(-2); reproductive tiller proportions by count and weight, weight tiller(-1); phytomers tiller(-1); leaf, stem, and inflorescence components of tiller weight; and sheath and stem components of phytomer weight. Biomass production was related to region of cultivar origin [e.g., Shawnee produced two times more than Dacotah (6.2 Mg ha(-1))]. Tiller density was highest for Dacotah (1090 tillers m(-2)) and lowest for Cave-In-Rock (520 tillers m(-2)). Reproductive tiller fractions by count were plastic and higher at Arlington (0.81) than Brookings (0.08). Weights per reproductive tiller ranged from 0.7 g (Dacotah) to 3.4 g (Cave-In-Rock). Phytomers per tiller was not plastic (5.2 for Dacotah to 7.4 for Cave-In-Rock). Internode weight exhibited a basipetal increase and was highly plastic. Cultivars responded similarly to location effects on tillers m(-2), weight tiller', and biomass production. Cultivar differences for biomass production were attributed to variation at tiller (phytomers tiller(-1)) and phytomer (weight phytomer(-1)) levels

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