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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 pan coefficient is coefficient to correlate a high rate of evaporation in a pan to an evaporation rate from larger water bodies [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 tropical karst (Keyword) returned 59 results for the whole karstbase:
Showing 31 to 45 of 59
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

Estimating recharge in a tropical karst aquifer, 2000, Jones I. C. , Banner J. L. , Humphrey J. D. ,
Unique constraints on seasonal and spatial variations in recharge to the Pleistocene limestone aquifer of Barbados are obtained from the analysis of oxygen isotopic compositions of groundwater and rainwater. Conventional methods of estimating recharge are based on groundwater chloride variations, coastal groundwater discharge, and potential evapotranspiration. These methods typically yield estimates of recharge for Barbados that range from 9% to 20% of average annual rainfall, with significant uncertainties that arise from poorly constrained model input parameters. Owing to the low relief and tropical climate of Barbados, variations in rainwater and groundwater delta(18)O values are primarily influenced by the amount of rainfall, with negligible temperature or altitude effects. Composite monthly rainwater delta(18)O values are inversely related to rainfall, while groundwater delta(18)O values show little seasonal variability. Rainwater delta(18)O values are equivalent to groundwater values only at the peak of the wet season. By using mass balance, the difference between groundwater and weighted-mean rainwater delta(18)O values gives recharge values. These values are in general agreement with estimates by conventional methods (10-20%) and provide unique additional information including the following: (1) Recharge is restricted to the wettest 1-3 months of the year, and (2) there is less recharge at higher elevations. The effective shift in delta(18)O values between contemporaneous rainwater and groundwater via recharge is a useful tool for estimating temporal and spatial variability in recharge and must be considered in paleoclimatic studies where climate inferences are based on groundwater delta(18)O values preserved in the geologic record

Post-Miocene subtropical karst evolution, lower Suwannee River basin, Florida , 2000,

Physical Mechanisms of River Waterfall Tufa (Travertine) Formation, 2001, Zhang David Dian, Zhang Yingjun, Zhu An, Cheng Xing,
Waterfall tufa is widely distributed around the world, especially in tropical and subtropical karst areas. In these areas river water is generally supersaturated with respect to calcite, and the precipitation occurs mainly at waterfall and cascade sites. Development of waterfall tufa has been described as simply being the result of water turbulence. We believe, however, that three physical effects can lead to tufa deposition at waterfall sites: aeration, jet-flow, and low-pressure effects. The three physical effects are induced by two basic changes in the water: an accelerated flow velocity, and enlargement of the air-water interface area. These two changes increase the rate of CO2 outgassing and the SIc, so that a high degree of supersaturation is achieved, which then induces calcite precipitation. These 'waterfall effects' have been simulated in laboratory and field experiments, and each of them can accelerate, or trigger, calcite precipitation. Field measurements of river water chemistry also show that tufa deposition occurred only at waterfall sites. In these experiments and observations, waterfall effects play the most important role in triggering and accelerating CO2 outgassing rates. Field and laboratory observations indicate that plants and evaporation also play important roles in tufa formation. Growth of algae and mosses on tufa surfaces can provide substrates for calcite nucleation and can trap detrital calcite, accelerating tufa deposition. However, the prerequisite for such deposition at waterfall sites is a high degree of supersaturation in river water, which is mainly caused by waterfall effects. Evaporation can lead to supersaturation in sprays and thin water films at a waterfall site and cause the precipitation of dissolved CaCO3, but the amount of such deposition is relatively small

Karst Features of Christmas Island (Indian Ocean), 2001, Grimes, Ken G.

Christmas Island (in the Indian Ocean) is an uplifted, composite, reef-carbonate island with a volcanic core. The coast is mostly cliffed and rises steeply via a series of terraces to a central phosphate-blanketed plateau. In spite of the high rainfall, there is little surface water as drainage is underground and karstic - it is initially stored in an epikarst aquifer, then follows the limestone/volcanic contact out to the island edge to emerge at major conduit springs. These springs are mostly at or below sea level, but some perched springs occur where the volcanic rocks appear at the surface. Caves occur at the present coast, as uplifted coastal caves, on the plateau, and there are a few pseudokarst caves. Cave development involves mixing zones between fresh and sea water in the coastal zone, and between vadose and phreatic waters perched on the volcanic rocks beneath the plateau. Cave locations and form are controlled by the rock structure (especially jointing) the location of the volcanic contact, and the combination of uplift with present and past sea levels - which controls the location of the mixing zone.

Remote Sensing and GIS-Based Analysis of Cave Development in the Suoimuoi Catchment (Son La - NW Vietnam), 2002, Hung, L. Q. , Dinh, N. Q. , Batelaan, O. , Tam, V. T. , Lagrou, D.
Integration of remotely sensed imagery with ground surveys is a promising method in cave development studies. In this research a methodology was set up in which a variety of remote sensing and GIS techniques support cave analysis in the tropical karst area of the Suoimuoi catchment, NW Vietnam. In order to extract the maximum information from different remotely sensed data, the hue invariant IHS transformation was applied to integrate Landsat multispectral channels with the high resolution Landsat 7 ETM panchromatic channel. The resulting fused image was used, after enhancement, to visually and digitally extract lineaments. Aerial photos evaluated the extracted lineaments. Based on lineament density indices a fracture zone favorable for cave development is defined. The distance between caves and faults was investigated as well as the correspondence between the cave occurrence and the fracture zone.

Variation of delta C-13 in karst soil in Yaji Karst Experiment Site, Guilin, 2002, Pan G. X. , He S. Y. , Cao J. H. , Tao Y. X. , Sun Y. H. ,
This study deals with delta(13)C variation in karst soil system of Yaji Karst Experiment Site, Guilin, a typical region of humid subtropical karst formations. Samples of near ground air, plant tissue, soil and water (soil solution and karst spring) were respectively collected on site in different seasons during 1996-1999. Considerable variation of delta(13)C values are not only found with different carbon pools of soil organic carbon, soil air CO2 and soil water HCO3-, but also with the soil depths and with different seasons during a year. The delta(13)C values Of CO2 both of near ground air and soil air are lower in July than those in April by 1parts per thousand-4parts per thousand PDB. Our results indicate that the delta(13)C values of carbon in the water and air are essentially dependent on interface carbon interaction of air-plant-soil-rock-water governed by soil organic carbon and soil CO2 in the system

Chinese karst terminology (Examples from tropical and subtropical karst), 2002, Ravbar Nataš, A

Good knowledge of terminology in different languages is indispensable to be able to present correctly the results of scientific work, for international cooperation of experts and for translating professional texts. Purpose of the present article is to represent the typical Chinese karst landscape and to explain the terms used in the country. Although karst researches in China are carried out separately from the karst-sciences of western countries, terms such as fengcong, fenglin, shilin are enforcing gradually into international karst terminology. Question how to introduce new terms into narrower professional public sphere with old terms already established, is still remaining open. Sometimes this is necessary since a new term is of somehow enriched meaning or is gathering more information and improving the understanding. Appropriateness of such decision should be estimated by further discussions, which should be based upon familiarity with the problem and not upon the sentimentality towards the terms, if these have born more general meaning up to this time.

Estimating recharge thresholds in tropical karst island aquifers: Barbados, Puerto Rico and Guam, 2003, Jones I. C. , Banner J. L. ,
The hydrology and geochemistry of groundwater in tropical island aquifers, such as Barbados, Guam and Puerto Rico, are significantly influenced by tropical climatic conditions. Recharge to these aquifers is the product of regional and local climate patterns that control rainfall. Oxygen isotopes can be used to estimate the amount and timing of recharge on these islands because seasonal fluctuations of rainwater oxygen isotopic compositions are related to the amount of rainfall. The karst aquifers on Barbados, Guam and Puerto Rico have similar rainwater and groundwater oxygen isotopic compositions. Comparison of groundwater and rainwater oxygen isotopic compositions in the three aquifers indicates that: (1) recharge occurs by rapid infiltration with little evaporation prior to recharge; and (2) recharge is associated with similar monthly rainfall thresholds of 190-200 mm. These rainfall thresholds are remarkably similar for three aquifers in different geographic locations. Differences between the spatial variations of groundwater oxygen isotopic compositions on Barbados and Puerto Rico can be attributed to the more complex groundwater flow system on Puerto Rico. The surprising similarities of hydrologic conditions under which recharge will take place can be attributed to similarities in climate and geologic conditions, such as soils and limestone bedrock, that exist on the three islands. We therefore speculate that similar recharge-rainfall thresholds may be observed in other tropical karst aquifers. (C) 2003 Elsevier Science B.V. All rights reserved

Hydrogeologic and climatic influences on spatial and interannual variation of recharge to a tropical karst island aquifer, 2003, Jones I. C. , Banner J. L. ,
[1] The hydrology and geochemistry of groundwater in tropical island aquifers, such as on Barbados, are significantly influenced by tropical climatic conditions. Recharge to these aquifers is the product of regional and local climate patterns that control rainfall. Oxygen isotopes can be used to estimate the amount and timing of recharge on these islands because seasonal fluctuations of rainwater oxygen isotopic compositions are related to the amount of rainfall. This study shows that estimates of average annual recharge to the limestone aquifer on Barbados vary widely, displaying a more direct relationship to the distribution of rainfall throughout each year than to total annual rainfall. Recharge estimates are higher during years when rainfall is concentrated in the peak wet season months than during years when rainfall is more evenly distributed throughout the year. The El Nino-Southern Oscillation appears to be partially responsible for these rainfall and recharge fluctuations. Knowledge of interannual variation of recharge and processes responsible is important because recharge variation must be considered when setting groundwater management policies related to groundwater availability

The earliest Chinese karstologist Xu Xiake, 2003, Ravbar Nataš, A

The first real scientific exploration of karst and karst caves in south China was undertaken by Xu Xiake (1587 - 1641). Chinese karst was studied by Xu Xiake for more than thirty years. He described his journeys to almost half of the territory of the Ming dynasty in his book ĹXu Xiake's travels« (ĹXu Xiake youji«), that was first published in 1642. He dedicated a lot of time to the research of the underground world by describing subterranean rivers and lakes as water resources. He also made ground plans of some caves, marked their entrances and described different shapes of speleothems. He first described different ways of climbing in caves and methods for cave research. Altogether he visited over 300 caves. Xu Xiake first described different types of the tropical karst and focused on the characteristics and reasons of the tower hills origin. He introduced the term fenglin (peak forest), which is still used in the scientific literature. However, he is not only the father of the modern speleology, karstology, geomorphology and geography in the Chinese scale but in a worldwide sense.

Stalactites extrieures dans les karsts tropicaux humides. Dpts stalagmitiques de tufs calcaires, 2004, Taborosi Danko, Hirakawa Kazuomi
Outside Stalactites in humid tropical karst Stalactitic deposits of calcareous tufa - Friable and porous stalactitic deposits composed of calcareous tufa rather than sparry calcite characteristic of normal cave stalactites are often encountered in the entrances of caves and plastered to cliffs in the humid tropics. Tufaceous stalactitic outside deposits are frequently mentioned in literature but are typically dismissed in a few sentences, even in review articles dedicated to calcareous tufa. Mostly based on fieldwork in the Mariana Island, we have identified a variety of depositional settings where stalactitic tufa occurs. These settings can be grouped into spelean, transitional, epigean, and littoral realms. Centimetre to tens of meters in scale, their overall shapes can be quite irregular, with crooked, bulbous, pendant-like, light-oriented and other deflected forms exceedingly common. The outside surfaces of these stalactites invariably lack the crystalline luster of cave speleothems and feel wet and pasty, or powdery and earthy when dry. They are often covered with organic coatings. Stalactitic tufas are generally lightweight, porous, and friable, and many small specimens are weak enough to be plucked by hand. Composed of layered microcrystalline material, sometimes reminiscent of chalk, these stalactites exhibit a bewildering variety of fabrics, which can be classified as encrusted, amorphous, and laminated. In addition, they contain much organic material, microbial structures, and detrital grains. A wide array of biota is associated with these features, and they are thought to form by biogenic mechanisms superimposed on abiotic physico-chemical precipitation from karst water. Biologic processes involved in the formation of stalactitic tufa are numerous and appear to involve hundreds of species. While it is now clear that stalactitic tufas are a result of abiotic and biogenic deposition, an additional possibility remains to be considered. It is not improbable that tufa-like stalactites could form by decay and diagenesis of true cave speleothems, if the latter are exposed at the land surface conditions. Stalactitic tufas represent a unique, subaerial variety of calcareous tufa rarely deliberated in karst literature.

Karren features in Island Karst: Guam, Mariana Islands, 2004, Taborosi D. , Jenson J. W. , Mylroie J. E. ,
Dissolutional sculpturing (karren) in island karst terrain is distinct from karren in inland continental settings, whether temperate or tropical. Reef, lagoonal and eolian limestones that form most young carbonate islands are eogenetic, meaning they have not undergone significant diagenesis and exhibit high primary porosity and extreme heterogeneity. These lithologic qualities, combined with other characteristics of island karst, including the effects of autogenic recharge, tropical climate, and the proximity of the ocean, result in the development of unique karren forms. Highly irregular, composite karren forms are dominant, while linear forms, especially hydrodynamically shaped features, are rare or absent. The most common karren type on Guam is an assemblage of densely packed solution pits, separated by jagged ridges and sharp tips. It dominates the surfaces of all young reef limestones and ranges in texture from extremely jagged coastal forms, to somewhat more subdued inland features. It covers large areas, forming karrenfelds of jagged pit and pinnacle topography. Lacking a unique and accurate geomorphic term, this karren assemblage exists in a variety of similar forms, and its development is poorly understood. We propose the term 'eogenetic karren,' as it emphasizes the eogenetic nature of host limestone as the common factor controlling the development of variants of this karren type, while avoiding references to geographic settings or any of the poorly understood and variable genetic mechanisms. In addition to eogenetic karren, other forms of karren occur on carbonate islands but are limited to specific lithologic and environmental settings. Hydrodynamically-controlled features, dominant in interior continental settings of both classical temperate and tropical karsts, are nearly absent on Guam and similar islands, and form only locally in outcrops of dense, diagenetically mature, and recrystallized, limestones

Cave un-roofing as a large-scale geomorphic process, 2006, Klimchouk Alexander
A morphogenetic approach appears to be the most sensible in defining the tiankeng as a typological category. Tiankengs are giant collapse dolines formed over large river caves, with continuous precipitous perimeter and a diameter-to-depth ratio between 0.5 and 2. The term bears an evolutionary meaning, referring to the youthful stage of open collapse doline development, and the relationship of tiankengs to large underground rivers. The latter criterion separates tiankengs from other types of giant collapse features, such as caprock collapses over evaporates or large collapses over hydrothermal cavities. The South China karst offers evidence that un-roofing of caves is a large-scale geomorphic process playing an important role in the formation of cone and tower karst. It is probably the major process in the origin of large depressions, gorges and valleys in tropical karst, although other geomorphic processes contribute to shaping and maturation of a landscape and eventually obscure the origin in unroofed caves. Many saddles between hills and towers in fengcong and fenglin karst may owe their origin to cave un-roofing.

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