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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 measuring flume is an artificial channel used for discharge measurements.?

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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 tropics (Keyword) returned 22 results for the whole karstbase:
Showing 1 to 15 of 22
Stalactite growth in the tropics under artificial conditions, 1981, De Bellardpietri E.

In Cave Oxidation of Organic Carbon and the Occurrence of Rainwater Inflow Cave Systems in the Seasonally Arid Lowland Tropics, 1987, Williamson, Kerry A.

Recent studies have shown that in cave oxidation of organic carbon can play a significant role in cave initiation and development. The production and flux of organic carbon in different seasonally arid and tropical karsts and in perpetually humid tropical karst is described, with particular consideration of the role of large particle size organic carbon. The model developed is used to explain the extent of rainwater inflow cave development and the apparent scarcity of such forms in the perpetually humid tropics plus arrested development in the seasonally arid sub-tropics.

The anthropogenic impact on karst in Papua New Guinea is briefly introduced and a specific case is presented detailing the effect of road erosion sediments on a small karst. The karst is in the perennially humid tropics and covered with primary rain forest. The road was placed high above the karst on steep friable rock and traverses several of its catchments. The changes to and the rate of burial of parts of the karst and the infilling of the caves are described. The karst drainage has altered, and there is increased water storage. The sediment build-up ceased in less than a year due to vegetation and stabilization of the road embankments. It is concluded that any construction within a catchment leading to a karst should be assessed as to its impact on the karst

Louie Creek is a karst springfed stream situated in the seasonally humid tropics of northwest Queensland, Australia. It rises as a series of small exsurgences along the eastern edge of the Barkly Tableland. As it enters the lowlands of the Carpentaria plain, the creek deposits tufa which produces a series of cascades. This modern tufa extends discontinuously for about 1.5 km. A series of ancient tufas, in places lying adjacent to sites of modern deposition, extends discontinously for about 8 km downstream. At least two ancient tufa units are preserved at one location, Little Indarri site. The older unit comprises a sequence of well-preserved barrages with an orientation transverse to present-day stream flow. In places, erosion has reduced these barrages to their calcrete substrate. The older tufa is overlain in places by sediment which has become cemented to form a second calcrete unit. This sediment is in turn succeeded by the younger ancient tufa. Subsequent river incision has removed part of the sediment from the older unit and exposed several contact points between the ancient tufa and calcrete units. Radiocarbon dating of the Little Indarri site tufas, as well as other ancient Louie Creek units, yielded apparent ages ranging from approximately 30 to approximately 14 ka BP, suggesting that conditions were sufficiently wet during the period immediately preceding and throughout the Last Glacial Maximum for tufa deposition to occur. However, ancient tufa formation occurred during a phase of net river aggradation. There is geomorphic evidence that such aggradation was a result of an increased sediment supply to the fluvial system, most likely in response to conditions drier than present. Results from studies elsewhere in the region support such a Late Pleistocene trend. Incision of Louie Creek, which postdates the youngest of the dated ancient tufas, is most likely to have resulted from a shift to wetter conditions during the early Holocene

Solutional landforms in quartz sandstones of the Sydney Basin, PhD thesis, 1995, Wray, R. A. L

Solutional landforms have been described for over a hundred years from limestone terrains and are termed karst. In many tropical regions landforms of similar morphology but on highly siliceous sandstones and quartzites have also recently been identified. The similarity of many of these features in morphology and also in genetic solutional processes to those on limestone has prompted recent calls for these quartzose landforms to also be regarded as true karst.
Although not unknown in temperate latitudes, these highly siliceous solutional landforms have been most commonly studied in present-day tropical regions, or areas believed to have been tropical in the recent past. This concentration of research in hot-wet areas, allied with the long held assertion of the insolubility of silica, especially quartz, led to a belief that tropical climatic conditions are necessary for karstic solution of these rocks. However, some of these quartzose solutional landforms are known in areas of temperate climate where there is little evidence for prior tropical conditions. A comprehensive worldwide review of these landforms, and the processes involved in their formation, has not previously been conducted and forms the basis from which this study stems.
The Sydney Basin in southeastern Australia has had a stable temperate climate for much of the Cainozoic with no evidence of tropical climate. The highly quartzose Permo-Triassic sandstones of this area have little carbonate, but nevertheless display a wide range of landforms morphologically similar to those both on limestones and also tropical quartzites These include large bedrock towers, grikes, caves, smaller solution basins and runnels, and even widespread silica speleothems. This study describes the morphology of this suite of landforms in detail, and provides a comparative analysis of these sandstone forms to those reported from quartzites of tropical areas and also their limestone analogues. Various microscopic and natural water chemistry analysis are then utilised in examining the poorly understood natural processes responsible for their formation. The process of sandstone solutional weathering in the Sydney Basin is also compared with that reported from the tropics, finding very little difference in either the form or magnitude of attack between these two climatically distinct regions. No previous studies have examined the wide range of solutional features found on quartz sandstones in one region of a climate comparable to Sydney, nor the processes involved in the genesis of these forms.

High-resolution temporal record of Holocene ground-water chemistry; tracing links between climate and hydrology, 1996, Banner Jl, Musgrove M, Asmerom Y, Edwards Rl, Hoff Ja,
Strontium isotope analysis of precisely dated calcite growth layers in Holocene speleothems from Barbados, West Indies, reveals high-resolution temporal variations in ground-water composition and may provide a new approach to documenting the links between climate variability and fluctuations in the hydrologic cycle such as recharge rates and flow paths. The speleothems grew in a cave that developed in a fresh-water aquifer in uplifted Pleistocene reef limestones. Three periods of ground-water Sr isotope evolution are observed: 87 Sr/ 86 Sr values decreased from 6 to 4 ka, increased from 4 to 1 ka, and decreased again after 1 ka. The Sr isotope oscillations appear to record periodic variations in the relative Sr fluxes to ground water from exchangeable soil sites vs. carbonate mineral reactions, as reflected in 87 Sr/ 86 Sr values of modern Barbados ground waters. A hydrologic model that explains changes in ground-water flow routes in karst aquifers as a function of amount of rainfall recharge can account for the speleothem Sr isotope record. Independent Holocene climate records that indicate a major period of aridity at around 1.3-1.1 ka in the American tropics correspond with periodic variations in rainfall on Barbados that are predicted by this hydrologic model

Forest recovery in the karst region of Puerto Rico, 1998, Rivera L. W. , Aide T. M. ,
Widespread deforestation has led to an increase in secondary forest in the tropics. During the late 1940s in Puerto Rico, forest covered only 6% of the island, but a shift from agriculture to industry has led to the increase of secondary forest. This study focuses on the regeneration of forest following the abandonment of pastures and coffee plantations located in the karst region of Puerto Rico. Alluvial terraces and sinkholes were the principal features used for pastures, shifting agriculture, and coffee plantations, whereas mogotes (limestone hills of conical shape) were burned periodically or cut for charcoal or wood production. Abandoned pasture sites had a greater woody species diversity in comparison with coffee sites. The density of woody stems was greater in the abandoned pasture sites and Spathodea campanulata was the dominant species. In coffee sites Guarea guidonia was the most abundant species. There was no difference in basal area between the two land uses. Canonical Correspondence Analysis applied separately to adults and seedlings clearly separated each community according to land use. Seedling composition in coffee sites indicates a resistance to change in terms of the dominant species while in the pasture sites the composition will change as the dominant species S. campanulata is replaced with more shade tolerant species. Patches of forest that remained on the steep sides of mogotes and the presence of bats appears to have enhanced forest recovery, but the land use history of these sites has affected the pattern of regeneration and will continue to affect forest dynamics for many years. The karst area is a critical environment for water resources and biodiversity and its conservation and restoration is essential. (C) 1998 Elsevier Science B.V. All rights reserved

The role of high-energy events (hurricanes and/or tsunamis) in the sedimentation, diagenesis and karst initiation of tropical shallow water carbonate platforms and atolls, 1998, Jan F. G. B. L. ,
Karst morphology appears early, even during carbonate sediment deposition. Examples from modern to 125-ka-old sub-, inter- and supratidal sediments are given from the Bahamas (Atlantic Ocean) and from Tuamotuan atolls (southeastern Pacific Ocean), with mineralogical and hydrological analyses. Karstification is favoured by the aragonitic composition of bioclasts coming from the shallow marine bio-factory. Lithification by aragonite cements appears as a rim around carbonate deposits and dissolution and non-cementation start at the same time on modern supratidal deposits (Andros micrite or atoll coral rudite) and provoke the formation of a central depression on small or large carbonate platforms. In fact, this early solution of the centre of platforms is closely related to the location of each of the studied examples on hurricane tracks. High-energy events, such as hurricanes and tsunamis, affect sediment transport but hurricanes also affect diagenesis as a result of the enormous volume of freshwater carried and discharged along their paths. This couple, lithification- solution, is localised at sea level and accompanies sea-level fluctuations along the eustatic curve. Because of the precise location of hurricane action all around the Earth, early karstification by aragonite solution, cementation and supratidal carbonate sediment accumulations thigh-energy trails) act together on all the platforms and atolls located inside the Tropics (23 degrees 27') between roughly 5 degrees-10 degrees and 25 degrees on both hemispheres. However, early karstification acts alone on shallow carbonate platforms including atolls along the equatorial belt between 5 degrees-10 degrees N and 5 degrees-10 degrees S. These early steps of karstification are linked to the ocean-atmosphere interface due to the bathymetrical position of shallow carbonate platforms, including atolls. They lead to complex karstified emerged platforms, called high carbonate islands, where carbonate diagenesis, together with the development of bauxite- and/or a phosphate-rich cover and phreatic lens, will occur. (C) 1998 Elsevier Science B.V. All rights reserved

The use of alkalinity as a conservative tracer in a study of near-surface hydrologic change in tropical karst, 1999, Chandler Dg, Bisogni Jj,
Water shortages commonly increase in frequency following forest clearance on lauds overlying karst in the tropics. The mechanism underlying this hydrologic change is likely to depend on the land use which follows forest cover. To determine the flow paths which prevail for a progression of land uses common to the uplands of Leyte, Philippines, samples of interflow were collected during the rainy season and titrated to determine their alkalinities. The ratio of the measured alkalinity to the value predicted by equilibrium calculations for each sample was used as an indication of the contact time of the water with the limestone. The responses of the alkalinity saturation ratio and the runoff depth to increasing rainfall depth were used to substantiate the hypothesis that epikarst infilling and changing soil structure create throttles to percolation and infiltration. The forest site was found to generate interflow primarily as pipe how, with the infiltration and percolation throttles rarely exceeded. Similarly, infiltration was not: limiting for the slash/mulch Site, however, level of soil disturbance was adequate to initiate a throttle at the epikarst which increased the volume of interflow generated. The total percolation was similar for the plowed and slash/mulch sites; however, the interflow was decreased at the plowed site by reduced infiltration at the soil surface. The throttles to surface infiltration and epikarst percolation were even greater at the pasture sites, resulting in high runoff generation. However, comparatively greater infiltration was observed in the pasture having contour-hedgerows. (C) 1999 Elsevier Science B.V. All rights reserved

Post-Miocene subtropical karst evolution, lower Suwannee River basin, Florida, 2000, Denizman C, Randazzo Af,
Morphometric characteristics of [~]25 000 karstic depressions suggest that the last phase of the post-Miocene karstic evolution within the lower Suwannee River basin of Florida has been controlled by the lower sea-level stands of the Pleistocene and the formation of the Suwannee River. During the Pleistocene, as interglacial seas retreated, marine terraces formed by sequential sea-level lowstands and the time period of subaerial exposure diminished toward the sea. Consequently, geomorphologically younger karst landforms formed as the elevation of marine terraces decreased. The evolutionary geomorphological development of this heavily karstified region produced more frequent and/or larger and more complex depressions at higher elevations. A geographic information system analysis of morphometric and spatial distribution parameters of the karstic depressions within the lower Suwannee River basin reveals that the Florida karst is represented by broad, shallow depressions with an average density of 6.07/km2 and an average pitting index of 14.5. Morphometric and spatial distribution parameters of karstic depressions show a great variation within the lower Suwannee River area and thus preclude a simple morphoclimatic classification of karst landforms. The Tertiary carbonate rocks of the subtropical Florida karst have relatively less joint frequency and significant primary porosity, and do not produce the extreme karst landforms observed in the massive limestones of the tropics

Climatic conditions during marine oxygen isotope stage 6 in the eastern Mediterranean region from the isotopic composition of speleothems of Soreq Cave, Israel, 2002, Ayalon A, Barmatthews M, Kaufman A,
At several times during marine oxygen isotope stage 6, the eastern Mediterranean region was influenced by two extreme climatic systems: the large ice sheet over northern Europe and the wet tropics associated with African monsoons. During this interval, two major climatic events occurred in the region; the sapropel S6 layer formed ca. 176 ka in the eastern Mediterranean basin owing to the increase in the African monsoon, and another event, although not large enough to form sapropel, occurred ca. 151 ka. The isotopic composition of Soreq Cave speleothems seems to record these events as very low {delta}18O-{delta}13C values dated as ca. 178 and 152 ka. The very low {delta}18O-{delta}13C values of -6{per thousand} and -11{per thousand} to -12{per thousand}, respectively, are typical of interglacial intervals, but here they were recorded during a glacial interval. Such low peaks indicate that in this part of the eastern Mediterranean region, i.e., Israel, the rainfall amount increased dramatically. Moreover, the isotopic record of the speleothems also shows that during the entire stage 6, although the climate was as cold as much of the last glacial, the conditions were never as dry

Late Ordovician environmental changes in Carnic Alps and central Nevada : a comparative study, 2003, Berry Wbn,
Correlation of the late Ordovician stratigraphic and faunal successions in the Carnic Alps, which lay in a mid-latitude site at the time, with those in Nevada, which was in the tropics at the time, reveal certain similarities. During much of the late Ordovician glacial interval, deep shelves in both areas were sites of carbonate debris flow accumulations. The debris was derived from inner or shallow shelf environments. Karst topographies developed in inner or shallow shelves in both areas during the later phase of glaciation and sea level drawdown. A quartz sand spread widely at the end of the glacial interval on deep shelf-slope environments in both areas. Perhaps coincidently, shelves in both areas were uplifted and exposed by tectonism after the late Ordovician glacial episode

Cadmium and zinc adsorption maxima of geochemically anomalous soils (Oxisols) in Jamaica, 2003, Davies Be, Vaughan J, Lalor Gc, Vutchkov M,
Soil samples were collected from a Miocene limestone area of Jamaica (Manchester Parish) where unusual accumulations of Cd and other metals have been described previously. The source of the metals is natural (geological). The soils are aluminous Oxisols and, geochemically, are closely similar to local karst bauxite deposits. For comparison a karst bauxite sample was collected from Alabama (USA) and an Ultisol sample from South Carolina (USA). All the Jamaican soils were in the pH range neutral to slightly alkaline and CaCO3 contents ranged from 1.3 to 23.1 %. Mean total Cd = 102.5 mg/kg (range 13.6-191.8 mg/kg) and mean Zn = 362.6 (range = 125.8-683.3) mg/kg. These values are higher than world averages. The mean readily exchangeable Cd was 0.05 (range 0.01-0.15) mmol/kg and for Zn mean = 0.02 (range 0.01-0.02) mmol/kg. Adsorption data were obtained experimentally and modelled using the Langmuir isotherm. For the Manchester soils the mean Cd adsorption maximum was 9.15 (range 2.26-32.0) mmol/kg; the values were higher than the karst bauxite sample (0.08 mmol/kg) or the Ultisol (0.08 mmol/kg). Reliable Zn isotherms were not obtained for all soils; for three Manchester soils the mean Zn sorption maximum was 2.99 mmol/kg compared with 3.13 mmol/kg for Cd in the same three soils. Mean Al and Fe values are 38.7% Al2O3 and 17.7% Fe2O3 compared with the Ultisol (14.5% Al2O3,11.3% Fe2O3) and the bauxite (52.6% Al2O3, 0.7%Fe2O3). Interpretation of the major element values and the known mineralogy of the soils implies that the high adsorption maxima of the Manchester soils can best be explained by their calcareous nature. It is concluded that the Manchester soils have ample adsorption capacity to trap any incoming Cd or Zn solutes

Symposium Abstract: An environmental model of fluvial Tufas of the seasonally wet tropics, Northern Australia, 2004, Carthew K. , Taylor M. , Drysdale R.

Biota and biological processes associated with subaerial tufa in the tropics, 2004, Taborosi D. , Hirakawa K.

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