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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 fouling is the process in which undesirable foreign matter accumulates in a bed of filter media or ion exchanger, clogging pores and coating surfaces and thus inhibiting or retarding the proper operation of the bed [6].?

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

Featured article from geoscience journal

Elsevier
Earth and Planetary Science Letters, 2011, Vol 301, Issue 3, p. 424-432
The initial stages of cave formation: Beyond the one-dimensional paradigm
Abstract:

The solutional origin of limestone caves was recognized over a century ago, but the short penetration length of an undersaturated solution made it seem impossible for long conduits to develop. This is contradicted by field observations, where extended conduits, sometimes several kilometers long, are found in karst environments. However, a sharp drop in the dissolution rate of CaCO3 near saturation provides a mechanism for much deeper penetration of reactant. The notion of a “kinetic trigger” – a sudden change in rate constant over a narrow concentration range – has become a widely accepted paradigm in speleogenesis modeling. However, it is based on one-dimensional models for the fluid and solute transport inside the fracture, assuming that the dissolution front is planar in the direction perpendicular to the flow. Here we show that this assumption is incorrect; a planar dissolution front in an entirely uniform fracture is unstable to infinitesimal perturbations and inevitably breaks up into highly localized regions of dissolution. This provides an alternative mechanism for cave formation, even in the absence of a kinetic trigger. Our results suggest that there is an inherent wavelength to the erosion pattern in dissolving fractures, which depends on the reaction rate and flow rate, but is independent of the initial roughness. In contrast to one-dimensional models, two-dimensional simulations indicate that there is only a weak dependence of the breakthrough time on kinetic order; localization of the flow tends to keep the undersaturation in the dissolution front above the threshold for non-linear kinetics.

Research Highlights
- A kinetic trigger is not a prerequisite for limestone cave formation. - The added spatial dimension has a larger impact on breakthrough times than a kinetic trigger. - Planar dissolution front in a fracture is unstable to infinitesimal perturbations. - The most unstable wavelength depends on reaction kinetics and flow rate. - The instability leads to the formation of rapidly advancing, wormhole-like channels.