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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. ...

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That hydrologic barrier is see barrier, hydrologic.?

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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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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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PO BOX 746, TROY, NY 12181-0746 USA
Carbonates and Evaporites, 2004, Vol 19, Issue 6, p. 93-106
The early Ordovician Majiagou reservoir of the Jingbian Field, northwest China: Karstic peritidal dolomite
Abstract:
The Jingbian Field is located in the central part of the Ordos Basin in the west part of the North China Platform. It is the largest gas field discovery in China in the 1980's. The field is an example of production from a paleogeomorphic trap formed by karstification of Lower Ordovician peritidal dolomites. In terms of gas potential, the Majiagou Formation is the more important stratigraphic unit. It is composed of six members, the uppermost member (O(1)m(6)) has been largely removed by prolonged Caledonian karst erosion, leaving the underlying (O(1)m(5)) member to provide the main pay for the field. In spite of the 163 wells drilled the field presents many problems and uncertainties because of the poor seismic definition of the pay zones and the great reservoir heterogeneity of the karst system. Statistical data from more than 30 wells show a poor correlation between individual well-flow rates and thickness of the karstic zone or distance of wells, relative to a paleochannel. This suggests karstification is not the most important factor controlling productivity. The release of organic acids (during maturation of the source rock) and fracturing in response to Cretaceous tectonic event appear to be key factors responsible for the productivity of the Majiagou-5 (O(1)m(5)) reservoir in terms of modifying and enlarging the pore network. Carboniferous clays provide an effective updip seal through the infill of karst-breccia zones. High productivity is prominent along structural axes where karstic fractures, solution vugs and caverns are interconnected by vertical to sub-vertical fractures. On the basis of pore-type the Majiagou-5 Member reservoirs can be divided into four reservoir types, each allowing differentiation of reservoir quality through characteristic porosity-permeability ranges and capillary-pressure curves. Key aspects which affect the commerciality of the field are still uncertain but with recent test wells producing gas with water, considerations should focus on the mechanism of weak edge-water drive and the need to predict fracture zones