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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 deviation is 1. deflection of a recording from a base line (e.g., the deviation from vertical of a borehole) [16]. 2. usually a sling of rope or tape attached to a natural anchor at one end and clipped to the rope with a karabiner at the other. used to avoid rub points on pitches [25]. synonym: redirection.?

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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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;
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Your search for paleoenvironment (Keyword) returned 52 results for the whole karstbase:
Showing 46 to 52 of 52
Speleothem deposition at the glaciation threshold An attempt to constrain the age and paleoenvironmental significance of a detrital-rich flowstone sequence from Entrische Kirche Cave (Austria), 2012, Meyer M. C. , Sptl Ch. , Mangini A. , Tessadri R.

Proxy records from high-altitude locations predating the Last Glacial Maximum are rare but could provide invaluable insights into the response of alpine catchments to the rapid climate fluctuations which characterized the last glacial period. Herewe present a detrital-rich flowstone record from Entrische Kirche Cave, an inneralpine cave situated close to the accumulation area of the Pleistocene ice-stream network of the European Alps that expanded repeatedly into the lowlands during glacial maxima. U–Th dating of this calcite is challenging due to high detrital Th. However, petrographic and stable isotope analyses in conjunction with associated clastic cave sediments provide useful insights into the climatic boundary conditions during speleothem formation and into the paleoenvironmental processes which operated in the ~2000 m-high catchment above the cave. Our data show that millennial-scale temperature fluctuations had a first-order control on the periglacial activity and vegetation in the catchmentwhich strongly influenced the formation and infiltration of detritus into the karst aquifer. The brown laminated and brown dendritic fabrics that compose much of the detrital-rich flowstone succession reflect these environmental processes. The temperature-dependence of periglacial and permafrost processes allows to constrain the amount of cooling relative to the present-day mean annual air temperature that is required to initiate detrital-rich calcite formation in Entrische Kirche Cave, i.e. −2.5 °C (minimum) to −6 °C (maximum), respectively. White inclusion-poor calcite that is intercalated with the detrital-rich calcite indicates warm (interstadial) conditions and geomorphological stability in the catchment area. One such phase has been U–Th dated to 88.3±6.9 ka (i.e. Greenland Interstadial 21 or 22). 


THE UNDERGROUND KARST OF THE NEOPROTEROZOC SERIES OF NIARI-NYANGA (CONGO AND GABON). A KARSTOGENESIS CONTROLLED BY ENVIRONMENTAL CHANGES, 2012, Peyrot, Bernard

The area of Niari-Nyanga, divided between Congo-Brazzaville and Gabon, corresponds to a Neoproterozoic synclinal whose schisto-limestones and dolomitic layers shelter many caves as well as vast underground karst systems that are hardly known. In a sub-equatorial climate characterized by sparse rainfall with very variable intensity, a dry season of five months and a savanna environment, the endokarst presents a vast array of forms with sometimes large, sometimes small dimensions. The caves are mostly horizontal and oriented along tectonic lines. Old fossil perched caves contrast with epiphreatic caves and drowned inaccessible systems. In current bioclimatic conditions, corrosion seems not very effective and not in equilibrium with some vast morphologies. The stacked levels, the presence of fossil speleothems and detritic material suggest a polyphase genesis in link with important paleoclimatic changes, where humid and dry periods alternate. Recent age dating with 14C on stalagmites show that the speleothemes are holocene and grew during the important rainfalls of this time, before drying up at the general chlimate change 3000 years before present. Thus, the endokarst of Niari-Nyanga as well as its neighbours is an archive of large importance.


Diagenesis of a drapery speleothem from Castaar Cave: from dissolution to dolomitization, 2012, Martnprez A. , Martngarca R. , Alonsozarza A. M.

A drapery speleothem (DRA-1) from Castañar Cave in Spain was subjected to a detailed petrographical study in order to identify its primary and diagenetic features. The drapery’s present day characteristics are the result of the combined effects of the primary and diagenetic processes that DRA-1 underwent. Its primary minerals are calcite, aragonite and huntite. Calcite is the main constituent of the speleothem, whereas aragonite forms as frostwork over the calcite. Huntite is the main mineral of moonmilk which covers the tips of aragonite. These primary minerals have undergone a set of diagenetic processes, which include: 1) partial dissolution or corrosion that produces the formation of powdery matt-white coatings on the surface of the speleothem. These are seen under the microscope as dark and highly porous microcrystalline aggregates; 2) total dissolution produces pores of few cm2 in size; 3) calcitization and dolomitization of aragonite result in the thickening and lost of shine of the aragonite fibres. Microscopically, calcitization is seen as rhombohedral crystals which cover and replace aragonite forming mosaics that preserve relics of aragonite precursor. Dolomitization results in the formation of microcrystalline rounded aggregates over aragonite fibres. These aggregates are formed by dolomite crystals of around 1 μm size. The sequence of diagenetic processes follows two main pathways. Pathway 1 is driven by the increase of saturation degree and Mg/Ca ratio of the karstic waters and is visible in the NW side of the drapery. This sequence of processes includes: 1) aragonite and huntite primary precipitation and 2) dolomitization. Pathway 2 is driven by a decrease in the degree of saturation of calcite and aragonite and Mg/Ca ratio of the cave waters, and it is observed in the SE side of the drapery. The diagenetic processes of the second pathway include: 1) calcitization of aragonite; 2) incomplete dissolution (micritization) of both aragonite and calcite; 3) total dissolution. This study highlights the importance of diagenetic processes on speleothems and their complexity. The correct interpretation of these processes is crucial for the understanding of possible changes in the chemistry of waters, temperature, or pCO2 and so is critical to the correct interpretation of the paleoenvironmental significance of speleothems.


Partial pressures of CO2 in epikarstic zone deduced from hydrogeochemistry of permanent drips, the Moravian Karst, Czech Republic, 2012, Faimon Jiř, , Lič, Binsk Monika, Zajč, Ek Petr, Sracek Ondra

Permanent drips from straw stalactites of selected caves of the Moravian Karst were studied during one-year period. A hypothetical partial pressure of CO2 that has participated in limestone dissolution, PCO2(H)=10-1.53±0.04, was calculated from the dripwater chemistry. The value significantly exceeds the partial pressures generally measured in relevant shallow karst soils, PCO2(soil)=10-2.72±0.02. This finding may have important implications for karst/cave conservation and paleoenvironmental reconstructions.


Differences in karst processes between northern and southern China, 2012, Hao Y. , Cao B. , Zhang P. , Wang Q. , Li Z. , Yeh T. C. J.

The east–west trending Tsinling Mountains in central China were uplifted at the end of the Middle Jurassic [176–161 million years ago (Ma)] in Yanshanian, thus effectively and geographically defining the northern climate as cold and dry, and the southern climate as warm and humid. Influenced by paleoenvironmental variation, the karst process shows differences between northern and southern China. Using the systems approach, the authors integrated the geologic history, climate, and hydrological conditions to analyze the causes of the karst differences in northern and southern China, as well as in the Tibetan Plateau. Carbonate rock deposition began in the Mesoproterozoic Era (1,600–1,000 Ma) in north China, and in the Sinian Sub-Era (825–570 Ma) in south China. In north China, the rock formation ended in the Mid-Ordovician (466 Ma), while in South China the deposition continued to the Triassic (250–200 Ma). Tibetan Plateau was deposited in the Late Permian (257–250 Ma). The different depositional environment caused different lithologies: the limestones are largely micritic in the north, but are massive and sparry in the south. The modern karst features were formed mainly in the Tertiary (53–2.6 Ma) and the Quaternary. In the Quaternary, the Tibetan Plateau arose sharply, which formed the monsoon system of East Asia, and loess started to deposit in north China, which partly delayed or prevented karstification in north China, and differentiated the karst features from those in south China. Thus, the karst process in north China is mainly hypogene, while the south is epigene in the Quaternary.


Differences in karst processes between northern and southern China, 2012, Hao Y. , Cao B. , Zhang P. , Wang Q. , Li Z. , Jim Yeh T. C.

The east–west trending Tsinling Mountains in central China were uplifted at the end of the Middle Jurassic [176–161 million years ago (Ma)] in Yanshanian, thus effectively and geographically defining the northern climate as cold and dry, and the southern climate as warm and humid. Influenced by paleoenvironmental variation, the karst process shows differences between northern and southern China. Using the systems approach, the authors integrated the geologic history, climate, and hydrological conditions to analyze the causes of the karst differences in northern and southern China, as well as in the Tibetan Plateau. Carbonate rock deposition began in the Mesoproterozoic Era (1,600–1,000 Ma) in north China, and in the Sinian Sub-Era (825–570 Ma) in south China. In north China, the rock formation ended in the Mid-Ordovician (466 Ma), while in South China the deposition continued to the Triassic (250–200 Ma). Tibetan Plateau was deposited in the Late Permian (257–250 Ma). The different depositional environment caused different lithologies: the limestones are largely micritic in the north, but are massive and sparry in the south. The modern karst features were formed mainly in the Tertiary (53–2.6 Ma) and the Quaternary. In the Quaternary, the Tibetan Plateau arose sharply, which formed the monsoon system of East Asia, and loess started to deposit in north China, which partly delayed or prevented karstification in north China, and differentiated the karst features from those in south China. Thus, the karst process in north China is mainly hypogene, while the south is epigene in the Quaternary.


Atmospheric Processes in Caves, 2013, James, J. M.

The cave atmosphere is placed in context as a geomorphic agent. The composition of cave air in well-ventilated caves isgoverned by exchange between surface and cave air. In poorly ventilated caves, its composition can be altered by dilution and production, and depletion of its components in the cave. Relative humidity is used to introduce water vapor as a critical component of cave air and its variations that result in evaporation of water and condensation of water vapor. The biogenicand inorganic reactions of oxygen and carbon dioxide control solution of limestone and precipitation of calcite. Condensation corrosion is a visual manifestation of atmospheric processes on bedrock and speleothems. Theories and experiment shave resulted in rates for condensation corrosion, which allow a preliminary assessment of its role as aspeleogenetic agent. The cave air carries particulates of both biogenic and inorganic origin; these can influence geomorphic processes in caves and provide significant paleoenvironmental information so as to past cave and surface events and climates. It is concluded that anthropogenic impacts can alter the atmospheric processes in caves.


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