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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 saturated is 1. referring to rock with water-filled voids. 2. referring to water which has dissolved as much limestone or other karst rock as it can under normal conditions [25].?

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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 model-calculations (Keyword) returned 5 results for the whole karstbase:
The occurrence of ozone concentrations and exposure indices related to the adverse effects of ozone upon vegetation are reported for four Finnish background stations. In Finland, ozone concentrations are often near the background tropospheric values of cn. 30 ppb. Very high concentrations are not observed. The maximum 1-h average in this data set was 79 ppb. The exposure parameter, which accumulates growing season 1-h average concentrations above a 40 ppb base-line in daylight hours, gave clearly different exposure sums for the stations. These values varied between 4000 and 8500 ppb-h in the southern archipelago, 3000-6500 ppb-h in the southern coastal region, 2000-4000 ppb-h in central parts of the country, and 400-1000 ppb-h in the northern parts of the country. The date of the start of the vegetative season is important in high northern latitudes, because the spring maximum of ozone concentrations is relatively intense compared to the summer maximum. In northern Scandinavia, ozone exposures are particularly sensitive to the date of the start of the growing season. The long daylight period in northern Scandinavia is less important in this respect, since during the growing season ozone concentrations are usually below 40 ppb during the morning and evening hours. A good correlation was found between growing season average concentrations of the sum of gaseous HNO3 and particulate NO3-, and on ozone exposure index which accumulates concentrations above a 40 ppb base-line, confirming the anthropogenic origin of the elevated ozone exposures

Strategic ground water management for the reduction of karst land collapse hazard in Tangshan, China, 1997, Wang H. T. , Li Y. X. , Wang E. Z. , Zhao Z. Z. ,
Karst land collapse is a geological hazard caused mainly by human activities such as the pumping of ground water. The present study is aimed at determining a management strategy to minimize the risk of karst land collapse in the urban area of Tangshan, China. A method of groundwater management for multi-aquifer systems with groundwater confined and unconfined interchange properties has been developed. A groundwater simulation model and a management model are constructed for the studied area. The data used by the simulation and management models include the geometry of the aquifer systems, the parameters of hydrogeology, the distribution of recharge, and discharge in the simulation period and the historical water table elevations. The results of the model calculations show that the total balance between recharge and discharge for both Quaternary and bedrock aquifers is 4.7 x 106 m(3) in the period from November 1989 to October 1990. The optimal annual average pumping rate from the underlying bedrock aquifer is some 25.8 x 10(6) m(3), which is 54.4% of that which was pumped out of the aquifer in the hydrological year of 1990. If the management plan is carried out, the groundwater level in the bedrock aquifer will recover its confined state in most of the areas at risk of land collapse. This is the most resistant state to collapse in terms of groundwater flow.

A rare landform: Yerkopru travertine bridges in the Taurids Karst Range, Turkey, 2002, Bayari Cs,
Two examples of travertine bridges are observed at 8 to 15 in above stream level in the Lower Zamanti Basin, Eastern Taurids, Turkey. Yerkopu-1 and Yerkopru-2 bridges are currently being deposited front cool karstic groundwaters with log P-CO2 > 10(-2) atm. The surface area and the total volume of travertine in Yerkopru-1 bridge are 4350 m(2) and 40 000 m(3), whereas the values for Yerkopru-2 are 2250 m(2) and 20000 m(3), respectively. The interplay of hydrogeological Structure, local topography, calcite-saturated hanging springs, algal activity and rapid downcutting in the streambed appear to have led to the formation of travertine bridges. Aeration through cascades and algal uptake causes efficient carbon dioxide evasion that enhances travertine formation. Algal curtains aid lateral development of travertine rims across the stream. Model calculations based on a hypothetical deposit in the form of a half-pyramid implied that lateral development should have occurred from both banks of the stream in the Yerkopru-1 bridge, whereas one-sided growth has been sufficient for Yerkopru-2. The height difference between travertine springs and the main strearn appears to be a result of Pleistocene glaciation during which karstic base-level lowering was either stopped or slowed down while downcutting in the main strearn continued. Copyright (C) 2002 John Wiley Sons, Ltd

Hydrogeological overview of the Bure plateau, Ajoie, Switzerland, 2003, Kovacs A. , Jeannin P. Y. ,
This study presents a hydrogeological synthesis of the most recent data from the Bure plateau in Ajoie, canton Jura, NW Switzerland. Included is a complete reappraisal of aquifer geometry and aquifer boundaries, the delineation of catchment areas based on tracing experiments, and the evaluation of the hydraulic role of different hydrostratigraphic units. Furthermore, it presents GIS-based calculations on the mean piezometric surface, the thickness of the unsaturated zone and on the thickness of the minimum and mean saturated zones. The spatial extension of the shallow karst zone is also evaluated. A coherent conceptual model and the two-dimensional steady-state combined discrete channel and continuum type numerical model of the aquifer has been constructed. The research site is 83 km(2) in area and is underlain by slightly folded layers of Mesozoic limestones and marls. The Bure plateau is dissected by normal faults, which form a succession of elongated horst and graben structures. The main aquifer consists of Maim limestones, with thicknesses varying between zero (eastern border) and 320 m (south-eastern regions). The aquifer is bounded from below by the Oxfordian Marls. The underlying sediments of Middle Jurassic age are considered to be hydraulically independent. The surface topography of the Oxfordian Marls reveals the periclinal termination of a wide anticline over the plateau and a syncline in the southern parts. The aquifer contains three marly intercalations. Tracing experiments prove that marl layers do not act as regional aquicludes. These experiments also allow for the division of the aquifer surface into several water catchments. Based on tracing tests and piezometric data a NW-SE oriented groundwater divide seems to extend in the regions of Porrentruy-Bure-Croix. Calculations of the average (matrix flow) and minimum (conduit flow) water tables indicate an extended shallow karst zone in the region of Boncourt-Buix-St-Dizier. The thickness of the saturated zone increases towards the extremities of the research site, being thickest in the South. The thickness of the unsaturated zone shows a large variation, reaching its maximum in the central areas. Numerical model calculations roughly reproduce the observed hydraulic heads and mean spring discharges, they confirm current ideas about hydraulic parameters and suggest the existence of extended karst subsystems throughout the model domain

Isotopic and geochemical evolution of ground and surface waters in a karst dominated geological setting: A case study from Belize, Central America, 2004, Marfia A. M. , Krishnamurthy R. V. , Atekwana E. A. , Panton W. F. ,
Analysis of stable isotopes and major ions in groundwater and surface waters in Belize, Central America was carried out to identify processes that may affect drinking water quality. Belize has a subtropical rainforest/savannah climate with a varied landscape composed predominantly of carbonate rocks and clastic sediments. Stable oxygen (delta(18)O) and hydrogen (deltaD) isotope ratios for surface and groundwater have a similar range and show high d-excess (10-40.8parts per thousand). The high d-excess in water samples suggest secondary continental vapor flux mixing with incoming vapor from the Caribbean Sea. Model calculations indicate that moisture derived from continental evaporation contributes 13% to overhead vapor load. In surface and groundwater, concentrations of dissolved inorganic carbon (DIC) ranged from 5.4 to 112.9 mg C/l and delta(13)C(DIC) ranged from -7.4 to -17.4parts per thousand. SO42, Ca2 and Mg2 in the water samples ranged from 2-163, 2-6593 and 2-90 mg/l, respectively. The DIC and delta(13)C(DIC) indicate both open and closed system carbonate evolution. Combined delta(13)C(DIC) and Ca2, Mg2 SO42- suggest additional groundwater evolution by gypsum dissolution and calcite precipitation. The high SO42- content of some water samples indicates regional geologic control on water quality. Similarity in the range of delta(18)O, deltaD and delta(13)C(DIC) for surface waters and groundwater used for drinking water supply is probably due to high hydraulic conductivities of the karstic aquifers. The results of this study indicate rapid recharge of groundwater aquifers, groundwater influence on surface water chemistry and the potential of surface water to impact groundwater quality and vise versa. (C) 2003 Elsevier Ltd. All rights reserved

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