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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 pavement is see limestone pavement.?

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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 atlantic-ocean (Keyword) returned 9 results for the whole karstbase:
The role of high-energy events (hurricanes and/or tsunamis) in the sedimentation, diagenesis and karst initiation of tropical shallow water carbonate platforms and atolls, 1998, Jan F. G. B. L. ,
Karst morphology appears early, even during carbonate sediment deposition. Examples from modern to 125-ka-old sub-, inter- and supratidal sediments are given from the Bahamas (Atlantic Ocean) and from Tuamotuan atolls (southeastern Pacific Ocean), with mineralogical and hydrological analyses. Karstification is favoured by the aragonitic composition of bioclasts coming from the shallow marine bio-factory. Lithification by aragonite cements appears as a rim around carbonate deposits and dissolution and non-cementation start at the same time on modern supratidal deposits (Andros micrite or atoll coral rudite) and provoke the formation of a central depression on small or large carbonate platforms. In fact, this early solution of the centre of platforms is closely related to the location of each of the studied examples on hurricane tracks. High-energy events, such as hurricanes and tsunamis, affect sediment transport but hurricanes also affect diagenesis as a result of the enormous volume of freshwater carried and discharged along their paths. This couple, lithification- solution, is localised at sea level and accompanies sea-level fluctuations along the eustatic curve. Because of the precise location of hurricane action all around the Earth, early karstification by aragonite solution, cementation and supratidal carbonate sediment accumulations thigh-energy trails) act together on all the platforms and atolls located inside the Tropics (23 degrees 27') between roughly 5 degrees-10 degrees and 25 degrees on both hemispheres. However, early karstification acts alone on shallow carbonate platforms including atolls along the equatorial belt between 5 degrees-10 degrees N and 5 degrees-10 degrees S. These early steps of karstification are linked to the ocean-atmosphere interface due to the bathymetrical position of shallow carbonate platforms, including atolls. They lead to complex karstified emerged platforms, called high carbonate islands, where carbonate diagenesis, together with the development of bauxite- and/or a phosphate-rich cover and phreatic lens, will occur. (C) 1998 Elsevier Science B.V. All rights reserved

Volcanic gaps and subaerial records of palaeo-sea-levels on Flores Island (Azores): tectonic and morphological implications, 1999, Azevedo Jmm, Ferreira Mrp,
The morphological evolution of Flores Island, as commonly observed for volcanic islands, suggests (1) the balance between constructive processes (effusive and moderately explosive volcanic activities and tectonic uplifting movements) and destructive processes (marine abrasion, stream erosion, crater-forming volcanic explosions, caldera collapses and tectonic subsidence) and (2) the recurrent fluctuations of the sea-level. Records of (a) gaps in the volcanic activity and (b) erosional and depositional marine activity are shown as: - epiclastic deposits of marine origin - erosional morphologies, such as abrasion platforms, terraces, cliffs and caves - intensive palagonitization of the volcanic rocks - vertical changes of the structures in the hydroclastic submarine formations. Taking into account (1) the vertical crustal movements (uplift and subsidence) which may occur in volcanic domains and (2) the sequence of regressive-transgressive trends in the relative sea-level as expressed by indicators of pale-sea-levels, it is assumed that the morphological evolution of Flores Island comprehends three main stages, The existence of important differences between the present-day altitudes of correlated marine records noted in Flores, in Santa Marie Island (Azores Archipelago) and Porto Santo Island (Madeira Archipelago) is related with their crustal behaviour and different volcanic and tectonic evolution.

Last interglacial reef growth beneath Belize barrier and isolated platform reefs, 2000, Gischler Eberhard, Lomando Anthony J. , Hudson J. Harold, Holmes Charles W. ,
We report the first radiometric dates (thermal-ionization mass spectrometry) from late Pleistocene reef deposits from offshore Belize, the location of the largest modern reef complex in the Atlantic Ocean. The results presented here can be used to explain significant differences in bathymetry, sedimentary facies, and reef development of this major reef area, and the results are significant because they contribute to the knowledge of the regional geology of the eastern Yucatan. The previously held concept of a neotectonically stable eastern Yucatan is challenged. The dates indicate that Pleistocene reefs and shallow-water limestones, which form the basement of modern reefs in the area, accumulated ca. 125-130 ka. Significant differences in elevation of the samples relative to present sea level (>10 m) have several possible causes. Differential subsidence along a series of continental margin fault blocks in combination with variation in karstification are probably the prime causes. Differential subsidence is presumably related to initial extension and later left-lateral movements along the adjacent active boundary between the North American and Caribbean plates. Increasing dissolution toward the south during Pleistocene sea-level lowstands is probably a consequence of higher precipitation rates in mountainous southern Belize

Weichselian palaeoclimate and palaeoenvironment in Europe: background for palaeogroundwater formation, 2001, Vaikmae R. , Edmunds W. M. , Manzano M. ,
A review is given of palaeoclimatic and palaeoenvironmental evidence across Europe for the Weichselian period relevant to interpreting the emplacement and circulation of groundwaters. In addition, this provides the background against which the evidence of past climates and environments contained in groundwaters in coastal areas of Europe, from the Baltic to the Atlantic Ocean may be compared. For much of the Weichselian, although significantly colder than at present, conditions were favourable for the recharge of groundwater, as shown, for example, by periods of speleothem growth. During the last glacial maximum (LGM) recharge is likely to have ceased over much of permafrost-covered Europe, although shallow groundwater recharge from meltwater (generated by the geothermal gradients) could have taken place beneath the ice where pressure relief through tunnel valleys may have occurred. Modern recharge could have started as early as 13 14C ka BP, but probably interrupted by the Younger Dryas between 11 and 10 14C ka BP. In the Baltic areas, ice-dammed lakes inhibited the start of the modern hydrogeological regimes until c. 10.3 14C ka BP. Tundra conditions prevailed over most of ice-free southern Europe at the time of the LGM. At this time the area south of the Portuguese-Spanish border retained a generally warm and relatively humid climate due to the maintenance of warmer sea-surface temperatures derived from Atlantic Ocean circulation. For most of coastal Europe, however, the most significant impact on groundwater circulation is likely to have been the lowering of sea levels that drained large areas of the shelf, such as the North Sea and the English Channel, and also had a significant impact on the Atlantic coast of the Iberian Peninsula where the maximum lowering of up to 130 m would have been experienced. This, together with the general changes in climate, would also have reorganized the atmospheric chemistry over sites in Europe that is likely to be recorded in the groundwater's chemical and isotopic signatures

Origin of atoll lagoons, 2001, Purdy Edward G. , Winterer Edward L. ,
A database of 301 atolls from the Pacific, Indian, and Atlantic Oceans has been analyzed with respect to factors governing maximum atoll lagoon depth. Statistically significant correlations between maximum atoll lagoon depth and both atoll area and present-day rainfall are viewed as the combined effect of paleorainfall precipitation and catchment area in contributing to overall atoll morphology. This interpretation is supported by the gross saucer-shaped morphology of several of the Lau group of the Fiji Islands, and the subsurface Cretaceous Golden Lane atoll of Mexico, where evidence of reef rim construction is lacking but evidence for significant solution relief is compelling. The contribution of reefs to atoll rim construction appears to be limited generally to [~]10 m, leaving more than 20 m of relief to be explained at most atolls. At a number of these, the last interglacial highstand surface is [~]15-20 m beneath Holocene rim sediments. Subsidence rates of even 5 cm/ k.y. do not suffice to explain the subsea depth of this unconformity, suggesting the dominating influence of solution on relief expression. Calculations of solution rates relative to the residence time of sea level below given depths during the past 700 k.y. suggest that the observed atoll relief is in part inherited from more than one Pleistocene, or perhaps earlier, glacial stage. Whatever the precise time of origin, the data available strongly suggest that atoll morphology is solution determined rather than growth predicated

Carbonate-Hosted Zn-Pb Deposits in Upper Silesia, Poland: Origin and Evolution of Mineralizing Fluids and Constraints on Genetic Models, 2003, Heijlen Wouter, Muchez Philippe, Banks David A. , Schneider Jens, Kucha Henryk, Keppens Eddy,
Microthermometric and crush-leach analyses of fluid inclusions in ore and gangue minerals of the Upper Silesian Zn-Pb deposits, Poland, along with first results of Rb-Sr geochronology on sulfides, provide important constraints on the paleohydrogeologic and metallogenetic models for the origin of these ores. The analyzed samples comprise two generations of dolomite, two generations of sphalerite, galena, and late calcite. The two dolomite generations and the late calcite were also analyzed for their oxygen and carbon isotope compositions, allowing a characterization of the mineralizing fluids. The ore-forming fluids represent highly saline (20-23 wt % CaCl2 equiv) Na-Ca-Cl brines, episodically introduced into the Triassic host carbonates. They had an oxygen isotope composition of ~0 per mil V-SMOW. Their Na-Cl-Br content (molar Na/Br and Cl/Br ratios between 99 and 337 and between 248 and 560, respectively) suggests that they originated by evaporation of seawater, which most likely occurred in the Permian-Triassic. The relative concentrations of potassium (molar K/Cl between 0.0147 and 0.0746) and lithium (molar Li/Cl between 0.0004 and 0.0031) further indicate that the fluids significantly interacted with siliciclastic rocks. The ionic and calculated oxygen isotope compositions of the fluids indicate that they were more evolved than present-day brines in the Upper Silesian coal basin, and the present-day brines show more extensive mixing with low-salinity fluids. The first results of direct Rb-Sr dating of ore-stage sulfides yield an isochron model age of 135 {} 4 Ma for the mineralizing event. This is consistent with hydrothermal activity and ore formation in Upper Silesia occurring in response to Early Cretaceous crustal extension preceding the opening of the northern Atlantic Ocean. The data presented support a model in which bittern brines migrated down into the deep subsurface and evolved into mineralizing fluids owing to extensive water-rock interaction. They were episodically expelled along deeply penetrating faults during the Early Cretaceous to form Zn-Pb deposits in the overlying Mesozoic carbonate rocks

The Ardeche endokarstic responses to the eustatic variations resulting from the Messinian salinity crisis, 2006, Mocochain L. , Clauzon G. , Bigot J. Y. ,
The Messinian salinity crisis is typically recorded by evaporites in the abyssal plains of the Mediterranean Sea and by canyons incised into the Mediterranean margins and their hinterlands. However, the impacts of crisis on geomorphology and surface dynamics lasted, until. canyons were filled by sediments in the Pliocene (fig. 2). In the mid-Rhone valley, the Ardeche Cretaceous carbonate platform is incised over 600 m by the Rhone Messinian canyon. The canyon thalweg is located - 236 m Lis) (below sea level) in the borehole of Pierrelatte [Demarcq, 1960; fig. 1]. During the Pliocene, this canyon was flooded as a ria and infilled by a Gilbert type fan delta [Clauzon and Rubino, 1992; Clauzon et al., 1995]. The whole Messinian-Pliocene third order cycle [Haq et al., 1987] generated four benchmark levels. The first two are [Clauzon, 1996]: (i) The pre-evaporitic abandonment Surface which is mapped around the belvedere of Saint-Restitut (fig. 1). This Surface is synchronous [Clauzon, 1996] of the crisis onset (5.95 Ma) [Gautier et al., 1994; Krigjsman et al., 1999] and, consequently, is an isochrounous benchmark. (ii) The Messinian erosional surface is also an isochronous benchmark due to the fast flooding [Blanc, 2002] of the Rhone canyon, becoming a ria at 5.32 Ma [Hilgen and Langereis, 1988]. These surfaces are the result of endoreic Mediterranean sea level fall more than a thousand meters below the Atlantic Ocean. A huge accommodation Space (up to more than 1000 in) was created as sea-level rose up to 80 in above its present-day level (asl) during (lie Pliocene highstand of cycle TB 3.4 (from 5.32 to 3.8 Ma). During the Lower Pliocene this accommodation space was filled by a Gilbert fan delta. This history yields two other benchmark levels: (i) the marine/non marine Pliocene transition which is an heterochronous surface produced by the Gilbert delta progradation. This surface recorded the Pliocene highstand sea level; (ii) the Pliocene abandonment Surface at the top of the Gilbert delta continental wedge. Close to the Rhone-Ardeche confluence, the present clay elevations Of file four reference levels are (evolution of base-level synthesized in fig. 4): (1) 3 12 in asl, (2) 236 in bsl, (3) 130 m asl, (4) 190 In A. The Ardeche carbonate platform underwent karstification both surficial and at depth. The endokarst is characterized by numerous cavities organised in networks. Saint-Marcel Cave is one of those networks providing the most coillplete record (fig. 5). It opens out on the northern side of the Ardeche canyon at an altitude of 100 m. It is made up by three superposed levels extending over 45 km in length. The lower level (1) is flooded and functionnal. It extends beneath the Ardeche thalweg down to the depth of 10 m bsl reached by divers. The observations collected in the galleries lead us to the conclusion that the karst originated in the vadose area [Brunet, 2000]. The coeval base-level was necessarily below those galleries. The two other levels (middle (2) and upper (3)) are today abandoned and perched. The middle level is about 115 m asl and the upper one is about 185 m A. They are horizontal and have morphologies specific to the phreatic and temporary phreatic zone of the karst (fig. 6). In literature, the terracing of the Saint-Marcel Cave had been systematically interpreted as the result of the lowering by steps of the Ardeche base-level [Guerin, 1973; Blanc, 1995; Gombert, 1988; Debard, 1997]. In this interpretation, each deepening phase of the base level induces the genesis of the gravitary shaft and the abandonment of the previous horizontal level. The next stillstand of base level leads to the elaboration of a new horizontal level (fig. 7). This explanation is valid for most of Quaternary karsts, that are related to glacio-eustatic falls of sea-level. However Our study on the Saint-Marcel Cave contests this interpretation because all the shafts show an upward digging dynamism and no hint of vadose sections. The same 'per ascensum' hydrodynamism was prevailing during the development of the whole network (figs. 8 and 9). We interpret the development of the Ardeche endokarst as related to the eustatic Messinian-Pliocene cycle TB 3.4/3.5 recorded by the Rhone river. The diving investigations in the flooded part of the Saint-Marcel Cave and also in the vaLlClusian springs of Bourg.-Saint-Andeol reached - 154 in bsl. Those depths are compatible only with the incision of the Messinian Rhone canyon at the same altitude (- 236 m bsl). The Saint-Marcel lower level would have develop at that time. The ascending shaping of levels 2 and 3 is thus likely to have formed during the ensuing sea-level rise and highstand during the Pliocene, in mainly two steps: (i) the ria stage controlled by the Mediterranean sea level rise and stillstand; (ii) the rhodanian Gilbert delta progradation, that controlled the genesis of the upper level (fig. 10)

How much did climate force the Messinian salinity crisis? Quantified climatic conditions from pollen records in the Mediterranean region, 2006, Fauquette S, Suc Jp, Bertini A, Popescu Sm, Warny S, Bachiri Taoufiq N, Perez Villa Mj, Chikhi H, Feddi N, Subally D,
The latest Miocene (5.96 to 5.33[no-break space]Ma) is characterised by an outstanding event: the desiccation of the Mediterranean Sea (Messinian salinity crisis). It has been suggested that this was caused by a tectonic event, with no climatic change playing a role in desiccation. Quantifying the climate of the region during this period will help support or refute this hypothesis. An effective method for reconstructing the climate from Neogene pollen data is the 'Climatic Amplitude Method' based on the modern climatic requirements of plants to interpret fossil data. It has been conceived especially for periods devoid of modern vegetation analogue.Twenty Messinian to Lower Zanclean pollen sequences are now available in the peri-Mediterranean region. Most of them do not cover the whole Messinian interval, particularly those along the Mediterranean shorelines where sedimentation was interrupted during the sea's desiccation. In contrast, sedimentation was almost continuous in such areas as the Atlantic side of Morocco, along the Adriatic coast (including the Po Valley), and to a lesser extent the Black Sea. The Mediterranean sites nonetheless provide a reliable if not a discontinuous record of vegetation variability in time and space.A first examination of the pollen diagrams reveals a high regional variability controlled by local conditions, and throughout the interval a southward increase in herb pollen frequency in contrast to the tree pollen frequency. This indicates that open and probably dry environments existed in the southern Mediterranean region prior to, during and after the salinity crisis. Trees developed in areas close to mountains such as in the Po Valley, in Cerdanya and in the Black Sea region. Most variations observed in the pollen diagrams are constrained by fluctuations of Pinus pollen amounts, indicating eustatic variations. Climatic quantification from pollen data does not show obvious climatic changes due to the desiccation of the Mediterranean Sea, especially in the dry and warm southwestern Mediterranean area (Sicily, southern Spain and North Africa). At Maccarone, along the Adriatic Sea, a decrease in temperatures of the coldest month and, less importantly, a decrease in mean annual temperatures, corresponding to a drastic vegetation change, are reconstructed. These temperature variations are assumed to be controlled by regional environmental changes (massive arrival of waters in this basin) rather than to reflect cooling, because some authors link the second phase of evaporite deposition to a period of global warming. Some migrations of plants probably occurred as a response to Mediterranean desiccation. But the climatic contrast which has probably existed at that time between the central Mediterranean and the peripheral areas might be amplified.Climatic reconstruction from pollen data in the western Mediterranean area shows that climate is not the direct cause of the Mediterranean desiccation, as the Mediterranean region had experienced continuously high evaporation long before the crisis. Therefore the main factor leading to this event seems to be the successive closures of the Betic and Rifian corridors, isolating the Mediterranean Sea from the Atlantic Ocean

Changing perspectives in the concept of 'Lago-Mare' in Mediterranean Late Miocene evolution, 2006, Orszagsperber Fabienne,
The Cenozoic Alpine orogeny caused the partition of Tethys into several basins. During the Late Neogene, the Mediterranean attained its final configuration, whereas, eastwards, the Paratethys, isolated from the World Ocean, disintegrated progressively into a series of smaller basins. As a result, an endemic fauna developed in these basins, mainly composed of brackish to freshwater faunas, indicating an environment affected by changes in water salinity. These small basins of the Paratethys were named 'Sea-Lakes' by Andrusov [Andrusov, D., 1890. Les Dreissenidae fossiles et actuelles d'Eurasie. Geol. min. 25, 1-683 (in Russian)]. Subsequently this name was translated into 'Lac-Mer' [Gignoux, M., 1936. Geologie stratigraphique, 2[deg]edition, Masson, Paris].In the Mediterranean isolated from the Atlantic at the end of the Miocene (Messinian), thick evaporites deposited, consisting of a marine Lower Evaporite unit and an Upper Evaporite unit, mainly of continental origin. Ruggieri [Ruggieri, G., 1962. La serie marine pliocenica e quaternaria della Val Marecchia. Atti Acad. Sci. Lett. Arti. Palermo, 19, 1-169.] used the term 'Lago-Mare', to characterize the brackish to fresh water environment which occurred within the Mediterranean at the end of the Messinian.During recent decades, numerous scientific investigations concerning the history of the Messinian within the Mediterranean were devoted to the understanding of conditions prevailing after the deposition of the marine evaporites. Brackish to freshwater faunas are found in several outcrops and boreholes in the Mediterranean, both in the uppermost beds of gypsum and inter-bedded within the clastic sediments of the Upper Evaporite Unit, immediately preceeding the flooding by the marine Pliocene waters. These faunas, because of their similarities with the fauna described in the Paratethys, were named 'Paratethyan', or 'Caspi-brackish' fauna, this leading some authors to imply a migration of these fauna from Paratethys to the Mediterranean. However, others refute this hypothesis.New data induced some researchers to consider that exchanges existed between the Mediterranean and the Eastern Paratethys and also between the Mediterranean and the Atlantic Ocean at the Miocene-Pliocene transition. These investigations now take advantage of the accurate time scales established by authors (biostratigraphy, cyclostratigraphy, magnetostratigraphy), allowing good stratigraphic correlations between the Mediterranean and the Paratethys, and precisions on the geodynamic evolution of this area.Furthermore, sediments at the base of the Zanclean (MPl1), locally containing brackish to fresh water faunas conducted authors to attribute this formation to an infra- or pre-Pliocene and also to a Lago-Mare 'event'.Thus, the 'Lago-Mare' concept drifted from its original meaning, and is evolving because of progresses in the understanding of the Mediterranean geodynamics and the adjacent areas during the Miocene-Pliocene transition

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