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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 cave ice is ice formed in a cave by natural freezing of water. loosely but incorrectly applied to calcium carbonate dripstone and flowstone [10].?

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

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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 extrusion (Keyword) returned 5 results for the whole karstbase:
Determination of escarpment age using morphologic analysis: An example from the Galilee, northern Israel, 2000, Matmon A. , Zilberman E. , Enzel Y. ,
We used topographic and structural data and very limited age control to perform quantitative morphometric analyses and to determine relative ages of escarpments bounded by late Cenozoic normal faults in the Galilee, Israel. The Galilee is an extensional zone composed of a series of uplifted and tilted blocks forming large escarpments built mainly of carbonate rocks. Two parameters used to discriminate tectonic stages are the ratio between the height of the escarpment and the total stratigraphic displacement (L) and the degree of concavity of escarpment slopes relative to a reference slope. The only dated reference slope is Mount Tur'an, [~]300 m high and formed by the Tur'an fault system, which has a total stratigraphic displacement of 625 m. A basalt flow that delimits the age of the Tur'an escarpment is dated to 4.23 {} 0.23 Ma and displaced 300 m, which is identical to the present-day topographic expression of this escarpment. The L value for this escarpment is [~]0.5. The Tur'an fault system was active prior to 4.23 Ma at slow uplift rates that enabled erosion to maintain the gentle slope over which the basalt flowed. Increased offset rates following the basalt extrusion led to the formation of the escarpment. The preservation of the basalt at the top of the escarpment indicates that erosional lowering of the upper surface of the Tur'an block has been minor since its formation. The L values indicate two stages of uplift; an early stage during which offset rates were probably low enough that they did not form topography, and a later stage that formed topography, which is preserved. The timing of the change in displacement rates from a slow continuous stage to a fast, topography-forming stage was determined by comparing the shape of the dated slope of Tur'an to that of other slopes. We conclude the following: (1) generally, the topographic profiles of different parts of each individual escarpment have similar shapes indicating similar ages; (2) escarpments having slopes that are more concave or convex than the reference Tur'an escarpment are older or younger than 4 Ma, respectively; and (3) the Galilee escarpments did not form simultaneously. A few escarpments were already major morphologic features by the early to middle Pliocene, whereas the rest formed during the late Pliocene. Morphometric analysis is a useful method for studying the geologic history of a landscape controlled by normal fault uplift and characterized by the absence of sediment deposition and where carbonate dissolution is the main erosional process. This and similar approaches can be used to discriminate tectonic stages and understand the relationship between tectonic activity and surface processes in other extensional regions

The Dachstein paleosurface and the Augenstein Formation in the Northern Calcareous Alps - a mosaic stone in the geomorphological evolution of the Eastern Alps, 2001, Frisch W, Kuhlemann J, Dunkl I, Szekely B,
The central and eastern areas of the Northern Calcareous Alps (NCA) are characterized by remnants of the Dachstein paleosurface, which formed in Late Eocene (?) to Early Oligocene time and is preserved with limited modification on elevated karst plateaus. In Oligocene time, the Dachstein paleosurface subsided and was sealed by the Augenstein Formation, a terrestrial succession of conglomerates and sandstones, which are only preserved in small remnants on the plateaus, some in an autochthonous position. Thermochronological data suggest a maximum thickness of the Augenstein Formation of >1.3 km, possibly >2 km. The age of the Augenstein Formation is constrained by the overall geological situation as Early Oligocene to earliest Miocene. Fission track age data support an Early Oligocene age of the basal parts of the formation. The source area of the Augenstein Formation consisted predominantly of weakly metamorphic Paleozoic terrains (Greywacke Zone and equivalents) as well as the Late Carboniferous to Scythian siliciclastic base of the NCA to the south of the depositional area. To the west, the Augenstein Formation interfingered with the Tertiary deposits of the Inntal. Sedimentation of the Augenstein Formation was terminated in Early Miocene time in the course of the orogenic collapse of the Eastern Alps. The Augenstein sediments were eroded and redeposited in the foreland Molasse zone. From Pannonian times (similar to 10 Ma) on, the NCA and the denuded Dachstein surface experienced uplift in several pulses. The Dachstein paleosurface has been preserved in areas, in which thick limestone sequences allowed subsurface erosion by cave formation and thus prevented major surface erosion

Dachstein-Altflche, Augenstein-Formation und Hhlenentwicklung - die Geschichte der letzten 35 Millionen Jahre in den zentralen Nrdlichen Kalkalpen., 2002, Frisch W. , Kuhlemann J. , Dunkl I. , Szekely B. , Vennemann T. , Rettenbacher A.
The landscape of the central Northern Calcareous Alps (NCA) is largely determined by the celebrate elevated karst plateaus, which represent relics of the Dachstein paleosurface and can be followed as far as the eastern margin of the NCA. The Dachstein paleosurface formed in late Eocene to early Oligocene times as a karstic hilly landscape. It was modified by later erosional processes to a limited extent only and is preserved as such in the karst plateaus. In the Oligocene, the paleosurface subsided and was sealed by the Augenstein Formation, a terrestrial sequence of conglomerates and sandstones, which are only preserved in small remnants on the plateaus. The poorly and contradictingly defined terms Rax landscape" and Augenstein landscape" are not used any more. From the overall geological situation, the age of the Augenstein Formation can be inferred as Lower Oligocene to early Lower Miocene. Fission track dating on zircon support the Lower Oligocene age of the basal Augenstein sediments (only these are preserved). Their source area was situated in the south and mainly occupied by weakly metamorphosed Paleozoic sequences (Graywacke Zone and its equivalents) and the latest Carboniferous to Lower Triassic siliciclastic base of the NCA. To the west, the Augenstein Formation interfingered with the Tertiary sediments of the Lower Inn Valley. Thermal modeling of fission track data from apatite, which is contained in pebbles as an accessory phase, suggest that the Augenstein Formation attained thicknesses of locally 1.3 km, possibly even more than 2 km. Augenstein sedimentation probably ended in Early Miocene times with the onset of lateral tectonic extrusion in the Eastern Alps, which caused lowering of the relief in the source area and created a new, fault-bounded river network. In the following period, the Augenstein sediments were eroded and redeposited in the foreland molasse basin. From Pannonian times (ca. 10 Ma) on, the central and eastern NCA, and therefore also the Dachstein paleosurface, experienced uplift in pulses. The paleosurface remained preserved in those areas, where thick limestone sequences enabled subsurface erosion in cave systems and considerably reduced surface erosion. Augenstein sediments became washed into the widespread cave systems of the plateau-topped limestone massifs. The arrangement of the caves in three horizons shows that uplift of the NCA occurred in pulses separated from periods of tectonic quiescence. In our model of the evolution of the NCA since the late Eocene, the highest cave system, the surface-near ruin cave system, was probably formed during formation of the Dachstein paleosurface. The largest system, the giant cave system, formed in Upper Miocene times, i.e., in the early stage of the final uplift period of the NCA. The youngest and lowest system, the source cave system, formed in Pliocene to Quaternary times. We aimed to date material from the giant cave system by radiometric methods. U/Pb dating on speleothems from the Mammut cave (Dachstein) and the Eisriesenwelt (Tennengebirge) gave no formation age because of the low U contents; however, the isotope ratios allow to infer that the speleothems formed in pre-Pleistocene time. Quartz pebbles from the Augenstein Formation, washed into the caves before the formation of the speleothems, were analyzer for cosmogenic beryllium and aluminum isotopes in order to date the time of redeposition. The isotope contents, however, did no yield a sufficiently strong signal. Oxygen and carbon isotope ratios were determined on the Eisriesenwelt speleothem in order to receive information on climatic changes during speleothem growth. A 260 mm long core from the outer zone of the speleothem shower limited variation for the temperatures of the seeping rainwater, which caused the speleothems to form. This indicates moderate climate and thus, again, pre-Pleistocene formation of the speleothems. All these results are in accord with the supposed Upper Miocene formation age of the giant cave system. Displacement of a speleothem along a shear plane and normal faults visible on the plateaus by the offset of the actual surface testify young, partly Quaternary tectonics, which affected the NCA.[ausfhrliche Darstellung, geol. Krtchen, Farbbilder, ganzes Heft.]

Dachstein-Altflche, Augenstein-Formation und Hhlenentwicklung - die Geschichte der letzten 35 Millionen Jahre in den zentralen Nrdlichen Kalkalpen, 2002, Frisch W. , Kuhlemann J. , Dunkl I. , Szekely B. , Vennemann T. , Rettenbacher A.
The landscape of the central Northern Calcareous Alps (NCA) is largely determined by the celebrate elevated karst plateaus, which represent relics of the Dachstein paleosurface and can be followed as far as the eastern margin of the NCA. The Dachstein paleosurface formed in late Eocene to early Oligocene times as a karstic hilly landscape. It was modified by later erosional processes to a limited extent only and is preserved as such in the karst plateaus. In the Oligocene, the paleosurface subsided and was sealed by the Augenstein Formation, a terrestrial sequence of conglomerates and sandstones, which are only preserved in small remnants on the plateaus. The poorly and contradictingly defined terms Rax landscape" and Augenstein landscape" are not used any more. From the overall geological situation, the age of the Augenstein Formation can be inferred as Lower Oligocene to early Lower Miocene. Fission track dating on zircon support the Lower Oligocene age of the basal Augenstein sediments (only these are preserved). Their source area was situated in the south and mainly occupied by weakly metamorphosed Paleozoic sequences (Graywacke Zone and its equivalents) and the latest Carboniferous to Lower Triassic siliciclastic base of the NCA. To the west, the Augenstein Formation interfingered with the Tertiary sediments of the Lower Inn Valley. Thermal modeling of fission track data from apatite, which is contained in pebbles as an accessory phase, suggest that the Augenstein Formation attained thicknesses of locally 1.3 km, possibly even more than 2 km. Augenstein sedimentation probably ended in Early Miocene times with the onset of lateral tectonic extrusion in the Eastern Alps, which caused lowering of the relief in the source area and created a new, fault-bounded river network. In the following period, the Augenstein sediments were eroded and redeposited in the foreland molasse basin. From Pannonian times (ca. 10 Ma) on, the central and eastern NCA, and therefore also the Dachstein paleosurface, experienced uplift in pulses. The paleosurface remained preserved in those areas, where thick limestone sequences enabled subsurface erosion in cave systems and considerably reduced surface erosion. Augenstein sediments became washed into the widespread cave systems of the plateau-topped limestone massifs. The arrangement of the caves in three horizons shows that uplift of the NCA occurred in pulses separated from periods of tectonic quiescence. In our model of the evolution of the NCA since the late Eocene, the highest cave system, the surface-near ruin cave system, was probably formed during formation of the Dachstein paleosurface. The largest system, the giant cave system, formed in Upper Miocene times, i.e., in the early stage of the final uplift period of the NCA. The youngest and lowest system, the source cave system, formed in Pliocene to Quaternary times. We aimed to date material from the giant cave system by radiometric methods. U/Pb dating on speleothems from the Mammut cave (Dachstein) and the Eisriesenwelt (Tennengebirge) gave no formation age because of the low U contents; however, the isotope ratios allow to infer that the speleothems formed in pre-Pleistocene time. Quartz pebbles from the Augenstein Formation, washed into the caves before the formation of the speleothems, were analyzer for cosmogenic beryllium and aluminum isotopes in order to date the time of redeposition. The isotope contents, however, did no yield a sufficiently strong signal. Oxygen and carbon isotope ratios were determined on the Eisriesenwelt speleothem in order to receive information on climatic changes during speleothem growth. A 260 mm long core from the outer zone of the speleothem shower limited variation for the temperatures of the seeping rainwater, which caused the speleothems to form. This indicates moderate climate and thus, again, pre-Pleistocene formation of the speleothems. All these results are in accord with the supposed Upper Miocene formation age of the giant cave system. Displacement of a speleothem along a shear plane and normal faults visible on the plateaus by the offset of the actual surface testify young, partly Quaternary tectonics, which affected the NCA.

Geology and models of salt extrusion at Qum Kuh, central Iran, 2004, Talbot C. J. , Aftabi P. ,
Profiles through the summit of a small nearly axisymmetric extrusion of Oligocene and Miocene salt, and simple analogue models of it, simulate the profiles of piles of ductile nappes extruded from convergent orogens. The salt extrudes from a reactive diapir along a major strike-slip fault at about 82 mm a(-1) and rises 315 m above the central plateau of Iran. The salt has the distinctive smooth profile of a viscous fountain in which an asymmetric apron of allochthonous salt gravity-spreads over its surroundings from a summit dome. Curtain folds developed in the source layer extrude from the diapir and are refolded by major recumbent folds with circumferential axes that simulate nappes. Minor flow folds with circumferential axes refold major folds in the top 10-50 m of surficial salt. Master joints > 100 m long indicate brittle failure of dilated salt by regional stress fields. Tuned to the dimensions of Qum Kuh, analytical and analogue models of viscous extrusions constrain the dynamic salt budget and a time of extrusion of at least 42000 years. New analogue models suggest that the number, amplitude and spacing of major recumbent folds within the extruded salt (and ductile nappe piles) record the number, amount and relative timing of fluctuations in the driving forces

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