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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 valley sink is (american.) an elongated closed depression or series of interconnecting depressions forming a valley-like depression. compare karst valley; uvala [10].?

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.

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Karstologia, 2005, Issue 0, p. 29-40
Contrôle structural et tectonique sur l’hydrogéologie karstique du plateau Mahafaly (domaine littoral semi-aride, sud-ouest de Madagascar)
Abstract:
Structural and tectonic control on karstic hydrogeology of the plateau Mahafaly (semiarid coastal area, South-West of Madagascar) - The southwestern coast of Madagascar is characterized by a semiarid climate and low fresh water resources, which slow down the economic development. The studied area, located south of Toliara, is separated into a western coast of aeolian dunes and sandstones, where most of the people live, and the eastern, almost unoccupied, calcareous Mahafaly plateau. The coastal aquifer is dominated by salty water. The conductivity, close to 6000µS/cm in the north, decreases to 3000µS/cm in the south. The coastal plain is bordered to the East by highly karstified Cenozoic limestone, separated by a north-south cliff corresponding to the Toliara fault scarp. Surveys in coastal wells and in karstic aquifers clearly point out tidal influence on piezometric level and conductivity. In the north, the limestone cliff is directly in contact with the sea, whose water contaminates the karstic aquifer according to tidal variations. In the south, fresh water flows out on the beach by resurgences in the Quaternary sandstones, probably connected to the Eocene limestones, 5 km to the east. Drillings and exploration of some shafts on the plateau permitted access to the ground water table. It displays various conductivities ranging between 1500µS/cm and 5000µS/cm, unusually high for a karstic aquifer far away from the coast. The mapping of such conductivities suggests more complex phenomena than only marine intrusions into the different aquifer systems. Chemical and isotopic analyses show an obvious seawater intrusion and evaporation influence for the coastal aquifer. Iin the karstic aquifer, however, trace element analyses evoke contamination by upwelling of deep mineralized water. Salty water is frequent eastward on the basement and in the Mesozic formations. Today, fracture zones in both the coastal sandstones and in the Cenozoic limestone units control ground water circulations. Such fractures result from extensional phases in the past. The surface joint directions N-S, NE-SW and NW-SE reflect the deep-seated horst and graben structures. Microtectonic analyses give evidence of a post-Eocene WNW-ESE extension, and recent seismic data define an E-W extensional regime. The underground flowpaths are mostly on fractures oriented along the present stress field. The tectonic history in the area and the chemical composition of the waters suggest a connection of the karst aquifer with circulations from deep formations through deep-seated faults belonging to the Toliara fault system. This could explain abnormal salinities in the karstic system, far away from the coast.