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Latest news:

The book "Hypogene Karst Regions and Caves of the World" is finished
The book “Hypogene Karst Regions and Caves of the World” is going to be published by Springer, in its series “Cave and Karst Systems of the World”.
Karst session at the AGU Fall 2016 Meeting in San Francisco
There will be a karst session at the AGU Fall 2016 Meeting in San Francisco, USA in December 12-16: Characterization, Modeling, and Remediation of Fissured, Carbonate, and Karst Groundwater Systems
A new book on caves and karst in Austria
A book "Höhlen und Karst in Österreich" (Caves and karst in Austria; Editors: Christoph Spötl, Lukas Plan & Ehrad Christian) will be printed until mid of July. Subscription is available.
Unusual perspective on caves
Many inspiring ideas on caves can be found in images created by children, generated by the International Contest of Kid’s Drawing "Caves in the Eyes of our Children".
Session on Karst Aquifers at the 43th IAH Congress, France
A call to submit an abstract to a session devoted to karst aquifers, which will be held in September in Montpellier during the 43rd IAH Congress

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Did you know?

That Manning equation is an equation used to compute the velocity of uniform flow in open channel: v=1.486/n r2/3 s1/2, where v is the mean velocity of flow (in cfs units), r is the hydraulic radius in feet, s is the slope of the channel or sine of the slope angle, and n is the manning roughness coefficient [1]. see also chezy equation; froude number; reynolds number.?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

Featured article from geoscience journal

Journal of Hydrology, 2010, Vol 386, Issue 1, p. 130-141
Karstification in unconfined limestone aquifers by mixing of phreatic water with surface water from a local input: A model
Abstract:

When water from the surface of a limestone plain seeps down through the fractured rock to the water table of an unconfined aquifer with low hydraulic gradient containing water saturated with respect to calcite, mixing of these waters causes renewed aggressivity. A model is presented, which describes the evolution of karstification by dissolutional widening of the fractures downgradient from the local input of surface water. The model couples flow in the fractures with dissolution rates. Dissolution rates are given by F = k (1 [1] c (x)/ceq)4, where c (x) is the calcium concentration at distance x from the entrance of the fracture, ceq is the equilibrium calcium concentration of the H2O–CaCO3–CO2 solution in the fracture, and k is a rate constant. The model describes two domains of waters saturated with respect to calcite at different partial pressure of CO2. At the borders of these domains the waters mix and create dissolutional widening of the fractures by mixing corrosion. A channel evolves along the border in the downgradient direction by about 100 m in 100 ky. Below this channel a zone of fractures with aperture widths up to 1 cm has originated. The change of the hydraulic conductivity in the mixing zone shifts the border of the domains, allowing the channel to grow in the downgradient direction. Below it the zone of widened fractures is invaded by saturated phreatic water and dissolution stops. This process continues at the downgradient part of the conduit. In summary, we find cave conduits evolving close to the water table, leaving significant cavernous structures below them. A variety of modelling scenarios with different choices of parameters show that this evolution is typical and changes only in details but not in its basic behaviour.