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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 coefficient of compressibility is compressibility is the aptitude of the soil to be deformed. it is expressed by means of a coefficient which is the ratio between a void ratio decrease from eo to e and an increase in effective stress. the value a v = e0-e)p represents the coefficient of compressibility for the range p0 to p0 + p.units are usually cm2/kg [21]. see also coefficient of volume compressibility.?

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.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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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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PO BOX 21, BEACONSFIELD HP9 1NS, BUCKS, ENGLAND
Journal of Petroleum Geology, 1999, Vol 22, Issue 5, p. 141-165
Basement lithology and its control on sedimentation, trap formation and hydrocarbon migration, Widuri-Intan oilfields, SE Sumatra
Abstract:
The Widuri-lntan oilfields produce from late Oligocene sandstones of the Talang Akar Formation, which were deposited in a fluid-to-deltaic setting on the NW side of the Asri Basin, offshore SE Sumatra. The Asri Basin is of rift origin and formed during the early Oligocene, with its axis oriented in a NE-SW direction. Approximately 310 million brls of oil have been produced from the fields within the 12-by-12 mile (20-by-20 km) study area. The oil occurs in a series of structural and stratigraphic traps within slightly sinuous to meandering channel sandstone bodies. The reservoir sequence (sandstone interbedded with minor mudstone and coal) overlies basement rocks, which are predominantly Cretaceous in age. Forty-nine well penetrations have shown that the basement is composed of one of four lithologies: IB hornblende granodiorite; (2) metamorphic rocks, mainly mica schist; (3) plugs of metabasalt and related volcanic rocks; or (4) dolomitic limestone. A combination of drill cuttings, sidewall and conventional cores and FMS/FMI images has been used to identify and map the distribution of basement rock type. The basement was subjected to exposure and deep weathering prior to the formation of the Asri Basin, as evidenced by the zones of surface alteration encountered during drilling. The basement palaeotopography had a strong influence on the later distribution of major fluvial channels and sand pinch-outs. Several major faults appear to be controlled by basement lithology, especially at the boundaries of granodiorite and metabasalt intrusives. An important shear zone, oriented NW-SE, appears to have offset the basement between the main Widuri and Intan fields, and was subsequently the site of silicification of the mica schists in the basement. The Lidya field is situated where the reservoir pinches out onto eroded areas of basement silicification along this shear zone. Palaeocurrents in the upper 34-2 and 34-1 channel sandstones in the Widuri field were controlled by the orientation of this basement feature . Drape and compaction ofOligocene Talang Akar Formation sediments over eroded volcanic plugs have defined or enhanced a number of structural/stratigraphic plays, including the Widuri and Chesy fields. From seismic and well evidence, the reservoir sequence at the Indri field is underlain by dolomitic limestone and exhibits a series of unusual karst-related sinkhole and collapse structures. These are circular to slightly elliptical in shape, and extend from basement level to over 900 ft vertically into the overlying Talang Akar Formation