Karst and Cave RSS news feed Like us on Facebook! follow us on Twitter!
Community news

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 clastokarst is karst phenomena in clastic rocks composed of detrital carbonate material [20]. synonyms: (french.) clastokarst; (german.) klastokarst?; (greek.) clastokarst; (italian.) carsismo clastico; (russian.) klastokarst; (spanish.) clastokarst; (turkish.) klastik karst; (yugoslavian.) klastokrs, klastokras, klastokarst.?

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

What is Karstbase?

Search KARSTBASE:

keyword
author

Browse Speleogenesis Issues:

KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
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;
See all featured articles from other geoscience journals

Sedimentary Geology, 2006, Vol 185, Issue 0, p. 159-173
Lower Eocene carbonate cemented chimneys (Varna, NE Bulgaria): Formation mechanisms and the (a)biological mediation of chimney growth?
Abstract:
In the area of Pobiti Kamani (Varna, northeast Bulgaria), massive carbonate cemented columns ('chimneys', up to 1.5 m diameter and 8 m high) and horizontal interbeds (2 within loose Lower Eocene sands. Field observations and petrographical and stable isotope geochemical characterisation of four studied locations reveal a relationship between these structures and processes of ancient hydrocarbon seepage. Column and interbed structures both consist of similar well-sorted silt- to sand-sized nummulitic host sediments, predominantly cemented by early diagenetic, low-magnesium calcite. Filamentous textures, about 10 [mu]m in diameter and 80-650 [mu]m long, are only locally detected within interparticle calcite cement of columns. Column samples from two sites reveal a similar, linear and inverse covariant trend of [delta]13C-[delta]18O values, which was interpreted as a mixing trend between two end member fluid/precipitation conditions, i.e. (1) a methane- and/or higher hydrocarbon-derived carbon member characterised by [delta]13C values as low as -[no-break space]43[per mille sign] and marine controlled precipitation conditions with [delta]18O of - 1 0.5[per mille sign] V-PDB and (2) a member with less contribution of methane which was mixed most likely with less depleted carbon sources explaining [delta]13C values ranging up to - 8[per mille sign] V-PDB. The corresponding, depleted [delta]18O values, with many samples clustering around - 8[per mille sign] V-PDB, are interpreted in terms of precipitation at elevated temperatures. This suggests the venting system was not a true 'cold' seep, sensu stricto. Furthermore, column cross-transects often document an internal pattern consisting of (concentric) zones with distinct isotopic signatures, which vary between the two end members. The mixing and internal pattern of column isotopic data, together with petrographical observations, are qualitatively interpreted as evidence of alternating precipitation conditions, controlled by varying seepage rates of a single fluid source at depth, during build-up of individual chimney pipes near the sediment surface. Based on several field observations, migration of the hydrocarbon-charged fluids in Lower Eocene times was possibly channelled along NE oriented faults. Isotopic signatures of calcite cemented horizontal interbeds, with depleted [delta]18O ratios as low as - 8.88[per mille sign] V-PDB and variable [delta]13C (- 1[per mille sign] to - 16[per mille sign], mainly around - 5[per mille sign] to - 7[per mille sign]) suggest that ascending fluids contributed to their cementation or resetted the calcite cement isotopic signature, predominantly during periods of active seepage of warmer fluids. Only few petrographical (and preliminary lipid-biomarker) evidence has been found, pointing to the presence or possibly former activity of microbiota, involved in carbon cycling and calcite precipitation, typical of cold seep settings. This may result from diagenetic alteration of organic components. However, considering the processes of chimney formation, a cementation process, governed by the inorganic oxidation of hydrocarbons in which interstitial oxygen is rapidly consumed without bacterial mediation, is considered