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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. ...

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That photosynthesis is the process by which green plants convert carbon dioxide and water into simple sugar. chlorophyll and sunlight are essential to the series of complex chemical reactions involved in the process [23].?

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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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Your search for pickeringite (Keyword) returned 2 results for the whole karstbase:
EVIDENCE FROM CERNA VALLEY CAVES (SW ROMANIA) FOR SULFURIC ACID SPELEOGENESIS: A MINERALOGICAL AND STABLE ISOTOPE STUDY, 2009, Onac B. , Sumrall J. , Wynn J. , Tamas T. , Dormiceanu V. , Cizma? C.

Over 30 caves are known to develop in the Jurassic and Cretaceous limestone that outcrops along the lower part of the Cerna Valley and its tributaries in southwestern Romania. There are three features that strike observers when entering most of these caves: a variety of sulfate speleothems, large amounts of bat guano (both fossil and fresh), and unusually high cave temperatures. Such thermal anomalies are rather uncommon in the ordinary cave environment. Along Cerna Valley, however, one can measure temperatures (in some cavities) as high as 40ºC. This situation is due to (i) presence of thermal water pools, (ii) hot water flowing along cave passages, (iii) hot steam rising up fractures from depth.
Seventy-four mineral samples were collected from eight caves in the Cerna Valley. These were investigated by means of X-ray diffraction, scanning electron microscope, and electron microprobe analyses. The minerals identified so far in Sălitrari, Ion Barzoni, Sălitrari 2, Diana, Adam, Despicătura, and Grota cu Aburi caves, are: calcite [CaCO3], aragonite [CaCO3], gypsum [CaSO4•2H2O], anhydrite [CaSO4], pickeringite [MgAl2(SO4)4•22H2O], halotrichite [Fe2+Al2(SO4)4•22H2O], kalinite [KAl(SO4)2•11H2O], melanterite [FeSO4•7H2O], apatite- (Ca(OH) [Ca5(PO4)3(OH)], brushite [CaHPO4•2H2O], darapskite [Na3(SO4)(NO3)•H2O], and nitratine [NaNO3]. The phosphates and nitrates (except for darapskite) were precipitated in a typical vadose environment from reactions between phosphoric solutions supplied by bat guano and limestone bedrock. Most of the sulfates and darapskite are the result of sulfuric acid speleogenesis.
In addition, sulfur isotope measurements (δ34S) on sulfate speleothems and spring waters were undertaken to determine the origin of cave sulfates (i.e., vadose, hypogene, bacteriogenic, etc.). The isotope measurements in the springs show sulfide δ34S ranges from -21.9‰ to 24.0‰ with a mean value of 6.6‰ (n=9), whereas the sulfate δ34S ranges from 16.6‰ to 71.3‰ with a mean value of 30.1‰ (n=10).
Three populations of sulfur isotope values (negative, near zero, and positive) were found in the caves. Samples from Barzoni Cave (the most distant cave from any modern thermal spring) are extremely depleted (-23 to -28‰). Sulfide values of the nearest springs are approximately -20‰. In Sălitrari Cave, the range of values was from -19.8 to +6.5‰. It is more than likely a reflection of the increase in completeness of the reduction of sulfate. The δ34S value of gypsum in Grota cu Aburi (active H2S hot steam cave) was 6.5‰. This value is similar to the sulfur isotopic composition measured in darapskite from Sălitrari Cave; thus, probably documenting earlier sulfuric acid activity in the latter cave.
The final population of caves, especially Despicătura and Diana caves, has enriched sulfur isotope values, which correspond well to the sulfide values of nearby springs. Diana Cave from which Diana 3 spring originates has a sulfide isotopic composition of +19‰, which is approximately the value of the mean of the cave sulfates from Diana Cave. This shows that the cave sulfate isotopic value is controlled by the sulfide, which (after being oxidized) reacts with limestone/marls to produce gypsum or other sulfate minerals.


The first cave occurrence of orpiment (As₂S₃) from the sulfuric acid caves of Aghia Paraskevi (Kassandra Peninsula, N. Greece), 2011, Lazaridis Georgios, Melfos Vasilios, Papadopoulou Lambrini

Orpiment, tamarugite and pickeringite occur in close association above the surface of thermal water cave pools in the active sulfuric acid caves of Aghia Paraskevi on the Kassandra peninsula, northern Greece. Gypsum also occurs as small interstitial crystals or encrustations. Orpiment is of high significance since it has not previously been reported as a cave mineral. In addition, tamarugite and pickeringite rarely occur in karst caves. Water from a borehole and a spring is of Na-Cl type and contains traces of CO2 and H2S. The B/Cl ratios indicate seawater participation with a possible mixing with geothermal water of meteoric origin. Oxidation of fumarolic H2S and incorporation of seawater is a possible cause for the deposition of tamarugite. Orpiment accumulated from vapors under sub-aerial conditions at low temperatures in acidic conditions through an evaporation-condensation process. Fluid cooling and/or acidification of the solution resulting from H2S oxidation were responsible for orpiment precipitation. Oxidation of H2S to sulfuric acid dissolved the limestone bedrock and deposited gypsum.


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