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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 volatiles is substances with relatively large vapor pressures. many organic substances are almost insoluble in water so that they occur primarily in a gas phase in contact with water, even though their vapor pressure may be very small [22].?

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 guam (Keyword) returned 15 results for the whole karstbase:
Showing 1 to 15 of 15
An Annotated Speleological Bibliography of Oceania, 1987, Bourke, R. Michael

A preliminary annotated speleological bibliography is presented for Oceania. The region covered extends from Irian Jaya (Indonesia) in the west to the Galapagos Islands (Equador) in the east. There are 268 references given from the following countries and territories: Antarctica, Belau, Cook Islands, Easter Island, Fiji, French Polynesia, Galapagos Island, Guam, Irian Jaya, Marian Islands, New Caledonia, Niue, Solomon Islands, Tonga, Vanuatu, Western Samoa, Wallis and Futuna.


Application of the natural electric field for detection of karst conduits on Guam, 1995, Lange A. L. , Barner W. L.

Karst geology and hydrology of Guam: A preliminary report, 1999, Mylroie J. E. , Jenson J. W. , Jocson J. M. U. , Lander M. A.

Simulated effect of vadose infiltration on water levels in the Northern Guam Lens Aquifer, 2000, Contractor Dn, Jenson Jw,
Regional-scale hydrology of the fresh water lens in the Northern Guam Lens Aquifer has been simulated in the past using a finite element, sharp interface computer model, SWIG2D. Systematic differences exist between observed and computed water levels. Computed seasonal peak water levels are higher, and the computed seasonal lows are lower than the respective observed levels. It is hypothesized that vadose storage must store a substantial amount of water during the wet season and release it gradually into the lens during the dry season. Flow through the vadose zone was simulated with a one-dimensional finite element, unsaturated flow program UNSATID, in which the van Genuchten model is used to characterize unsaturated diffuse flow through the matrix of the vadose zone. An additional parameter (SINK) was added to the van Genuchten set to account for rapid infiltration down open pathways (fractures) associated with the closed depressions of the karst terrain. A global-optimization technique (Shuffled Complex Evolution or SCE-UA Method) was used to obtain the parameters that minimized the difference between simulated and observed water levels. Simulations incorporating the van Genuchten model were accomplished by combining the two programs, UNSATID and SWIG2D, into a single program. The sum-of-squared-errors (SSE) between computed and observed water levels in four observation wells was minimized using SCE-UA, reducing the arithmetically averaged SSE of the four wells by 30% compared with the SSE obtained when the vadose zone was not modeled. These results suggest that vadose storage is significant. On the other hand, the fact that the best fit obtained with an optimum parameter set was able to reduce the SSE by no more than 30% suggests that additional phenomena have yet to be accounted for to mon fully explain differences between simulated and observed well water levels. (C) 2000 Elsevier Science B.V. All rights reserved

Guam and the Carbonate Island Karst Model, 2000, Mylroie J. , Jenson J.

Karst Features of Guam in Terms of a General Model of Carbonate Island Karst, 2001, Mylroie, J. E. , Jenson, J. W. , Taborosi, D. , Jocson, J. M. U. , Vann, D. T. , Wexel, C.

The Carbonate Island Karst Model applied to Guam., 2001, Mylroie J. , Jenson J.
The karst of tropical carbonate islands is unique because: 1) fresh water-salt water mixing occurs at the base and margin of the fresh-water lens; 2) glacioeustasy has moved the freshwater lens up The karst of tropical carbonate islands is unique because: 1) fresh water-salt water mixing occurs at the base and margin of the fresh-water lens; 2) glacioeustasy has moved the freshwater lens up and down through a vertical range of over 100m; and 3) the karst is eogenetic, i.e., it has developed in young carbonate rocks that have never been buried beyond the range of meteoric diagenesis. Carbonate islands can be divided into three categories based on basement-sea level relationships: simple carbonate islands (no non-carbonate rocks), carbonate cover islands (non-carbonate rocks beneath a carbonate veneer), and composite islands (carbonate and non-carbonate rocks exposed on the surface). These ideas form the Carbonate Island Karst Model (CIKM) which can be visualized in terms of a three-dimensional framework, with island size on the x-axis, sea-level change on the y-axis, and bedrock relationships on the z-axis. On Guam, tectonic uplift and glacio-eustatic sea level change have produced a complex history on this composite island. The aquifer is partitioned in the subsurface by the .intecedent topography of the volcanic core of the island, and lens discharge is both diffuse and conduit controlled.

Freshwater resources on Guam: Calculating halocline position and fresh water discharge via temperature profile., 2001, Gamble D. W. , Mylroie J. E. , Jenson J. W. , Carew J. L. , Taborosi D. , Jocson J. M. U. , Vann D. T. , Mylroie J. R.

Recharge and aquifer response: Northern Guam Lens Aquifer, Guam, Mariana Islands, 2002, Jocson J. M. U. , Jenson J. W. , Contractor D. N. ,
The Northern Guam Lens Aquifer is an island karst aquifer in uplifted young, highly conductive limestone. Calculations of recharge based on differences between daily rainfall and daily pan evaporation suggest that the maximum annual mass of water delivered to the freshwater lens is about 67% of mean annual rainfall. Hydrographs of daily well-level responses plotted against daily rainfall indicate that the rate at which water is delivered to the lens is a function of rainfall intensity and the relative saturation of the vadose zone. Together, these variables determine the degree to which stormwater is shunted into fast flow through preferred pathways that bypass the bedrock matrix, rather than percolating slowly through the bedrock matrix. Data from the 40-year interval from 1956 to 1995 show that some 17% of rainfall on northern Guam arrives in small amounts (<0.6 cm/day). Most of this light rainfall is probably lost to evapotranspiration. At least another 20% of total rainfall on Guam arrives at very high intensities (>5.0 cm/day), which tend to promote fast flow at the expense of percolation. Rapid recovery of the water table from rapid recharge suggests that the lens either takes such recharge into storage very rapidly, discharges it rapidly without taking it into storage, or some combination of both. Significant vadose buffering of recharge to the lens is indicated by the fact that simulations assuming that the recharge from precipitation received in any given month is transmitted to the lens during the same month consistently over-predict observed peak mean monthly water levels and under-predict the minima. (C) 2002 Elsevier Science B.V. All rights reserved

Zones of enhanced dissolution and associated cave morphology in an uplifted carbonate island karst aquifer, northern Guam, Mariana Island, 2003, Taboroi D. , Jenson J. W, Mylroie J. E.

n contrast to Paleozoic limestones where drainage is based on classical cave systems (secondary porosity), young limestones of uplifted carbonate islands retain substantial distributed primary porosity. Consequently, speleogenesis on such islands is restricted to environments where dissolution is sufficiently focused to produce caves. Thus, on Guam and similar islands, solution voids large enough for human traverse occur only in settings where dissolution has been focused by hydrologic or geologic boundaries. In the vadose zone, these boundaries are lithologic contacts or structural discontinuities that channel the flow of aggressive water. In the phreatic zone, the boundaries are hydrologic contacts, where aggressive water is produced through the mixing of saturated waters. These geologic and hydrologic settings are sites of significant speleogenesis, each characterized by morphologically and hydrologically distinct types of caves.


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

A frequency domain approach to groundwater recharge estimation in karst, 2004, Jukic D. , Icjukic V. ,
This paper presents an alternative method for determining the values of parameters of a groundwater recharge model. The phreatic zone of a karst aquifer is considered as the linear and time-invariant filter that transforms the input signal of groundwater recharge rates into the output signal of spring discharges. Similarities between transfer functions of total rainfall rates and transfer functions of groundwater recharge rates are the basis for developing the parametric periodogram depending on parameters of a groundwater recharge model. The values of parameters are estimated by minimizing the differences between the parametric periodogram and a periodogram of spring discharges. The approximate Whittle log likelihood function is the criterion for determining the optimal values of the parameters. By using this frequency domain approach, groundwater-balance calculations are avoided so the method can be applied on unexplored karst aquifers when groundwater-balance cannot be achieved without extensive geologic and hydrogeologic investigations. The results of the applications on two springs located in the Dinaric karst area in Croatia are discussed. (C) 2003 Elsevier B.V. All rights reserved

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

A hypothesis for carbonate island karst aquifer evolution from analysis of field observations in northern Guam, Mariana Islands, 2013, Jenson John W. , Taborosi Danko, Rotzoll Kolja, Mylroie John E. , Gingerich Stephen B.

A hypothesis for carbonate island karst aquifer evolution from analysis of field observations in northern Guam, Mariana Islands, 2013, Jenson J. W. , Taboroi D. , Rotzoll K. , Mylroie J. E. , Gingerich S. B.

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