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 pressure cell is a pressure measuring and transducing device [16].?

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

What is Karstbase?



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.
Engineering challenges in Karst, Stevanović, Zoran; Milanović, Petar
See all featured articles
Featured articles from other Geoscience Journals
Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
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
See all featured articles from other geoscience journals

Search in KarstBase

Your search for clay minerals (Keyword) returned 26 results for the whole karstbase:
Showing 1 to 15 of 26
Karst-like features in badlands of the Arizona Petrified Forest, 1963, Mears Brainerd,
Sinks, disappearing streams, hanging valleys, and natural bridges add a karst-like element to the miniature mountain topography represented in badlands. The Chinle Formation [Triassic] of the Petrified Forest in Arizona largely consists of compact, montmorillonitic and illitic claystones. Sinks in it result from disaggregation of swelling clay minerals rather than solution which affects limestone in true karsts. Ravines whose bottoms are pierced by sinks may develop into hanging valleys because their channels, robbed of surface flow downstream from these swallow holes, cannot keep pace with downcutting in the master drainage to which they are tributary. Growth of the sinks soon creates a disappearing stream that continues to deepen the upstream segment of a ravine. Thus the abandoned downstream segment beyond the sinks, no longer eroded by the stream, develops into a transverse barrier. Where the abandoned channel was initially short, the barrier may be eventually narrowed by weathering and slope erosion to form a natural bridge. Other bridges consist of jumbled material. that has collapsed from steep valley walls, undercut by small stream meanders

Scanning electron microscope study of bauxites of different ages and origins, 1978, Bardossy G, Csanady A, Csordas A,

Colour In Some Nullarbor Plain Speleothems, 1982, Caldwell J. R. , Davey A. G. , Jennings J. N. , Spate A. P.

Chemical and mineralogical analyses of 18 speleothem samples from Nullarbor Plain caves are related to their colours ranging from white to black through browns and reds. Iron, manganese and organic compounds are the pigments responsible but their effect is variable according to their manner of incorporation in the speleothems and possibly also to the intervention of clay minerals. Closer studies are necessary to unravel these aspects and to investigate sequences of colour in speleothem growth.

Physical arrangement of high-alumina clay types in a Missouri clay deposit and implications for their genesis, 1983, Keller W. D. , Stevens R. P. ,

Karst du Rawyl (Hautes Alpes calcaires de Suisse occidentale), matires dissoutes et en suspension emportes par les sources, 1984, Wildberger, A.
HIGH ALPINE KARST OF RAWYL (SOUTHWESTERN SWITZERLAND): DISSOLVED AND SUSPENDED MATERIALS IN THE WATER OF KARSTIC SPRINGS - The karst of the Rawyl area is located between 1200 and 3250m elevation, at an average height of 2500m. The mean annual rainfall is about 2m. The output of dissolved and suspended material was measured at various important springs, subjected to a glacial to nivo-glacial discharge pattern. The dissolution rate is around 0,06 to 0,075 mm/year of which 1 to 25% are suspended materials, the rest being transported under dissolved form. The flushed material does not correspond exactly with the lithology of the aquifer: for the dissolved material, Mg is in excess compared to the Mg in the carbonates (exchange of cations Ca-Mg); for the suspended material, the clay minerals clearly out-weight the quartz (selection by different sizes and forms).

L'halloysite karstique; comparaison des gisements types de Wallonie (Belgique) et du Perigord (France), 1997, Perruchot A. , Dupuis C. , Brouard E. , Nicaise D. , Ertus R. ,
Two cryptokarstic (covered karsts) halloysitic deposits were compared: the Entre Sambre et Meuse in Belgium and the Perigord in France. Both belong to a continental margin subject to marine transgression and regression cycles which enhance the karstic activity. This geodynamic context appears to be very favourable to the formation of halloysite. The similarity of the geodynamic context of both sites leads to a genetic convergence linked to specific properties of the cryptokarstic system, especially, the ability to collect the percolating waters and to juxtapose the conditions of precipitation, accumulation and maturation of the halloysite silico-aluminous gel precursors. However, each site also displays pronounced specificities relevant to: the nature of the host rock of the halloysite (a partly silicified limestone in the first, a smectite-kaolinite argilite in the second); the aluminium source (allochthonous in the first, relatively autochthonous in the second); and the halloysite content of the deposits (of approximately 100% in the first, and 40% maximum in the second)

Ground-water silicifications in the calcareous facies of the Tertiary piedmont deposits of the Atlas Mountain (Hamada du Guir, Morocco), 1997, Thiry M. , Benbrahim M. ,
The Tertiary piedmont deposits (Hamada Formations), on the southern edge of the Haut-Atlas mountains, form extensive tablelands in the Boudenib area. They consist of two main sedimentary sequences, the Hamada de Boudenib and the Hamada du Guir, of Eocene and Miocene age. Both sequences show elastic facies at their base (conglomerates, calcareous sandstones, silty clays) and end with thick lacustrine limestones and pedogenic calcretes are characterised by rather confined facies, palygorskite-rich, with some gypsum in the second sequence. The recent evolution of the region is marked by the dissection of the tableland that is lined with high cliffs. The water flaw is mainly through wide karst features as there is no major river on the tableland. Silicifications which affect the different facies, form pods of various shape and size, and show an erratic spatial distribution. In the calcareous sandstones, there are irregularly shaped tubules of about 5 cm in diameter, more planar bodies from 5 to 50 cm thick, which frequently display voids lined with translucent silica concretions. The conglomerates display relatively few silicifications, the more characteristic ones consist of a silica cortex on some Limestone pebble and silica plates fitting closely the base of the pebbles. The lacustrine limestones and the calcretes from the upper part of the formation show frequently well developed silicifications. These show very variable shapes; horizontally stretching layers, interconnected or isolated amoeba-like bodies, thin slabs, karst micro-breccia, with frequent concretionnary structures, and quartz crystallisations. Limestone nodules remain often included in these silicifications. The more argillaceous facies display either small tubules or thin plates formed of translucent concretionnary silica. As a rule, the importance of the voids and related structures (concretions, drusy crystals) has to be noticed in all these silicifications, sometimes they are also linked with fractures or karst pipes. Petrography of the silica minerals, their relation with the primary structures. their distribution and their succession, give invaluable information on the silicification processes. Microcrystalline and fibrous quartz are the most common silica minerals, including minor amounts of opal and euhedral quartz. But micrographic arrangements show clearly that primary opal deposits have been more extensive and have recrystallized into chalcedony, microcrystalline quartz, or even ''flame-like'' quartz. Silica deposits in voids make up an important part of the silica pods. The tubules and thin plates of translucent silica of the argillaceous facies are formed of laminar chalcedony deposited around voids. Silica deposits in voids are also particularly obvious in the sandstones. The pores between the quartz grains are then cemented by fibrous quartz and little opal. Some samples show very large cemented voids that cannot be related to the primary porosity of the sandstone. These large voids correspond to the dissolution of the primary calcareous cement, which even led to the collapse of the sandstone fabric. In the limestones, there are silicified micro-karst breccia with a very high primary porosity cemented by quartz crystals, and even in the large microcrystalline quartz zones there are numerous void fillings, the primary porosity often exceeding 50%. There is obviously the alternation of silica deposits and calcite dissolution. Beside the void filling, silicifications comprise also matrix epigenesis, that is replacement of the carbonate by silica with preservation of most of the limestone structures, without development of voids. Nevertheless, the epigenesis of the limestone matrix is restricted to the vicinity of the voids. The silicifications relate to diagenetic processes. The main part of the silica is formed of void deposits and matrix replacement (epigenesis) on the edge of the voids. These void deposits give evidence of the feeding solutions. The regularity of the deposits all around the voids point out to a hydrologic regime characterised by a ground-water our now. Silica originates most probably from alteration of the magnesian clay minerals along the ground-water path. Regarding the low solubility of silica in surficial waters, high flows are needed in order to renew continuously the silica precipitated from solution. This points to a relatively humid climate at time of silicification, and to relief and incised landscapes to bring about these high flows

A mineralogical analysis of karst sediments and its implications to the middle-late Pleistocene climatic changes on the Tibetan Plateau, 1998, Zhang D. D. ,
The minerals in various categories of Tibetan karst sediments were divided into three groups: carbonate, iron and silicate. The carbonate minerals, including calcite, aragonite and dolomite, consist mainly of speleothem, tufa and sinter. Most of the speleothems indicates wetter and warmer periods in early and middle Pleistocene, the youngest being 194,000 years old. The second formation of carbonate mineral, tufa, implies an arid period starting 91,000 years BP. The iron minerals, goethite and hematite, are often mixed up with cave alluvial sediments that are interbedded with flowstones, and the depression sediments. They indicate strong oxidizing environments during their deposition, which is absent at present. The clay minerals, specially kaolinite, were contained in cave alluvial, flowstone and the depression sediments as well. Combined with stratigraphic study and U-series dating, the mineral analysis shows that warmer and wetter climates, which were suitable for speleothem development, probably disappeared 200 ka ago, and drier and colder climates dominated this plateau since then

Diagenetic concretions from the cave clastic sediment, Cave in Tounj quarry, Croatia, 1998, Lackovič, Damir

Diagenetic concretions from Cave in Tounj quarry (central Croatia) are studied. Concretions are found in non-cemented unsorted clastic cave deposit. They consist of particles of different size (clay to pebble) and from different provenance. One part of calcite and clay minerals are coming from speleothems and cave walls limestone. Detrital particles: chert, quartz, muscovite, chlorite, ilmenite, magnetite and most of clay, are probable transported into the cave from Triassic and Pleistocene clastic sediments from the surface. Autochthonous constituents of concretions are limonitic pizoids and some calcite cement. Composition of concretion is similar to the composition of surrounding non-cemented sediment.

Clays in Caves of the Guadalupe Mountains, New Mexico, 2000, Polyak, V. J. , Gven, N.
The origins of clay minerals in the caves of the Guadalupe Mountains, New Mexico are categorized as (1) detrital, (2) inherited from the weathering of dolostone and siltstone, and (3) authigenic. Clay minerals found in these caves include hydrated halloysite, kaolinite, dickite, illite, montmorillonite, illite-smectite mixed-layers, palygorskite, and trioctahedral smectite. The detrital clay minerals are montmorillonite, illite, dickite and kaolinite. The clay minerals inherited from the bedrock by condensation-induced weathering (in wall residues) are illite and dickite. Cave-authigenic clay minerals include hydrated halloysite (endellilte), trioctahedral smectite, montmorillonite, and probably palygorskite. Hydrated halloysite formed by the alteration of illite, montmorillonite, illite-smectite mixed-layers, kaolinite, or dickite during sulfuric acid-related speleogenesis. Trioctahedral smectite precipitated with Mg-carbonate minerals in dolomite crusts and huntite moonmilk. Montmorillonite formed in saturated ledge deposits of redistributed wall residues. Less clear is the origin of palygorskite in laminated silt and clay deposits in Carlsbad Cavern.

Tertiary weathered sediments located immediately to the west of the harbor at Newhaven, Sussex, UK, were investigated by examination of major and trace elements by scanning electron microscope (SEM), microprobe, and inductively coupled plasma mass spectrometer (ICP-MS), and the mineralogy was studied by optical petrography, X-ray diffraction (XRD), transmission electron microscope (TEM), selective leaching, and thermodynamic modeling. Studied outcrops experienced acid leaching by sulfuric acid percolating downward through Tertiary sediments overlying Cretaceous chalk. The progressive neutralization of the percolating acid fluids resulted in 'sequentially' layered neoformation of minerals: jarosite, iron oxides, aluminous minerals (sulfates, oxyhydroxides), gypsum, and Fe-Mn oxides. Substantial agreement was found between field observations and mineral assemblages obtained by modeling with the program CHILLER. These results suggest that the initial assumptions on the weathering process and mechanisms are correct. The relevance and implications of this study in the modeling of future denudation and weathering processes of radioactive waste-disposal sites (both deeply buried sites for high-level waste and surface sites for low-level waste) are discussed. Neoformed phases, such as jarosite, aluminous minerals, and silico-aluminous gels may play a significant role in the efficient trapping of mobilized pollutant radionuclides

Lechuguilla Cave is a hypogene cave formed by oxidation of ascending hydrogen sulfide from the Delaware Basin. A unique sediment deposit with characteristics suggesting derivation from the land surface, some 285 m above, was investigated. At this location, the observed stratigraphy (oldest to youngest) was: bedrock floor (limestone), cave clouds (secondary calcite), calcite-cemented silstone, finely laminated clay, and calcite rafts. Grain-size analysis indicates that the laminated clay deposits are composed of 59-82% clay-size minerals. The major minerals of the clay were determined by X-ray diffraction analysis and consist of interstratified illite-smectite, kaolinite, illite, goethite, and quartz. Scanning electron microscopy observations show that most of the clay deposit is composed of densely packed irregular-shaped clay-size flakes. One sample from the top of the deposit was detrital, containing well-rounded, silt-size particles. Surface soils are probably the source of the clay minerals. The small amount of sand- and silt-size particles suggests that detrital particles were transported in suspension. The lack of endellite and alunite is evidence that the clays were emplaced after the sulfuric-acid dissolution stage of cave formation. Fossil evidence also suggests a previously existing link to the surface

Trioctahedral smectite is a constituent of Mg-rich carbonate crusts and moonmilks (pasty deposits) in caves of the Guadalupe Mountains of southeastern New Mexico. Energy dispersive X-ray microanalysis of individual crystallites and their aggregates along with the X-ray diffraction analysis indicates that the smectite is probably stevensite. Saponite is likely present in some samples also. The smectite is intimately associated with dolomite crusts and huntite moonmilks in Carlsbad Cavern, Lechuguilla Cave, and other dolostone caves. Clay particles appear as fibers and films, with aggregates comprising decimicron-sized filamentous masses that envelop crystals of dolomite, huntite, and magnesite. The occurrence of smectite is related to the genesis of the Mg-rich carbonate minerals. In water films, progressive evaporation and carbon dioxide loss results in the sequential precipitation of Mg-rich calcite, aragonite, dolomite, huntite, and magnesite. This sequence of carbonate precipitation removes Ca and greatly increases the Mg/Ca ratio in the solutions. Silica is commonly available probably because of high pH conditions, and consequently, smectite forms in the Mg-rich alkaline environment. Along with the Mg-rich carbonate minerals, opal, quartz, and uranyl vanadates may precipitate with the smectite

Nordstrandite from Lages represents the first occurrence of this mineral in an oxisoil that does not involve the influence of a calcareous substrate. This is also the first reported occurrence in Brazil. Nordstrandite occurs near the city of Lages only in the weathered bedrock facies, mostly where the circulation of meteoric water is restricted. There is also a close association between nordstrandite and the weathering of modified pseudoleucite structures. The interaction of meteoric water and feldspathic alkaline country rock with uncommon texture and mineralogy (rich in nepheline, sodalite, nosean, analcime and natrolite) promotes the development of solutions enriched in alkaline ions with basic pH, necessary to form nordstrandite. A detailed study by X-ray diffraction (XRD) and infrared (IR) spectroscopy in natural or chemically leached samples was performed to identify the Al(OH)3 polymorphs of gibbsite and nordstrandite

Existence of karsts into silicated non-carbonated crystalline rocks in Sahelian and Equatorial Africa, hydrogeological implications, 2002, Willems Luc, Pouclet Andre, Vicat Jean Paul,
Various cavities studied in western Niger and South Cameroon show the existence of important karstic phenomena into metagabbros and gneisses. These large-sized caves resulted from generalized dissolution of silicate formations in spite of their low solubility. Karstification is produced by deep hydrous transfer along lithological discontinuities and fracture net works. The existence of such caves has major implications in geomorphology, under either Sahelian and Equatorial climate, and in hydrogeology and water supply, particularly in the Sahel area. Introduction. - Since a few decades, several karst-like morphologies are described in non-carbonated rocks (sandstones, quartzites, schistes, gneisses...) [Wray, 1997 ; Vicat and Willems, 1998 ; Willems, 2000]. The cave of Guessedoundou in West Niger seems to be due to a large dissolution of metagabbros. The cave of Mfoula, South Cameroon, attests for the same process in gneisses. This forms proof that big holes may exist deeper in the substratum even of non-carbonated silicate rocks. Their size and number could mainly influence the landscape and the hydrogeology, especially in the Sahelian areas. Guessedoundou, a cave into metagabbros in West Niger. - The site of Guessedoundou is located 70 km south-west of Niamey (fig. 1). The cave is opened at the top of a small hill, inside in NNE-SSW elongated pit (fig. 2 ; pl. I A). The hole, 3 to 4 m deep and 20 m large, has vertical walls and contains numerous sub-metric angular blocks. A cave, a few meters deep, comes out the south wall. Bedrocks consist of metagabbros of the Makalondi greenstone belt, a belt of the Palaeoproterozoic Birimian Formations of the West Africa craton [Pouclet et al., 1990]. The rock has a common granular texture with plagioclases, partly converted in albite and clinozoisite, and pyroxenes pseudomorphosed in actinote and chlorite. It is rather fairly altered. Chemical composition is mafic and poorly alkaline (tabl. I). A weak E-W schistosity generated with the epizonal thermometamorphism. The site depression was created along a N010o shear zone where rocks suffered important fracturation and fluid transfers, as shown by its silification and ferruginisation. The absence of human activity traces and the disposition of the angular blocks attest that the pit is natural and was due to the collapse of the roof of a vast cavity whose current cave is only the residual prolongation. To the vertical walls of the depression and at the cave entry, pluridecimetric hemispheric hollows are observed (pl. I B). Smooth morphology and position of these hollows sheltered within the depression dismiss the assumptions of formation by mechanical erosion. In return, these features are typical shape of dissolution processes observed into limestone karstic caves. That kind of process must be invoked to explain the opening of the Guessedoundou cave, in the total lack of desagregation materials. Dissolution of metagabbro occurred during hydrous transfer, which was probably guided by numerous fractures of the shear zone. Additional observations have been done in the Sirba Valley, where similar metabasite rocks constitute the substratum, with sudden sinking of doline-like depressions and evidence of deep cavities by core logging [Willems et al., 1993, 1996]. It is concluded that karstic phenomena may exist even in silica-aluminous rocks of crystalline terrains, such as the greenstones of a Precambrian craton. Mfoula a cave into gneisses in South Cameroon. - The cave of Mfoula is located 80 km north-east of Yaounde (fig. 3). It is the second largest cave of Cameroon, more than 5,000 m3, with a large opening in the lower flank of a deep valley (pl. I C). The cavity is about 60 m long, 30 m large and 5 to 12 m high (fig. 4; pl. I D). It is hollowed in orthogneisses belonging to the Pan-African Yaounde nappe. Rocks exhibit subhorizontal foliation in two superposed lithological facies: the lower part is made of amphibole- and garnet-bearing layered gneisses, and the upper part, of more massive granulitic gneisses. Average composition is silico-aluminous and moderately alkaline (tabl. I). The cave is made of different chambers separated by sub-cylindrical pillars. The ceiling of the main chamber, 6 m in diameter, is dome-shaped with a smooth surface (D, fig. 4). The walls have also a smooth aspect decorated with many hemispherical hollows. The floor is flat according to the rock foliation. They are very few rock debris and detrital fragments and no traces of mechanical erosion and transport. The general inner morphology is amazingly similar to that of a limestone cave. The only way to generate such a cavity is to dissolve the rock by water transfer. To test the effect of the dissolution process, we analysed a clayey residual sampled in an horizontal fracture of the floor (tabl. I). Alteration begins by plagioclases in producing clay minerals and in disagregating the rock. However, there is no more clay and sand material. That means all the silicate minerals must have been eliminated. Dissolution of silicates is a known process in sandstone and quartzite caves. It may work as well in gneisses. To fasten the chemical action, we may consider an additional microbial chemolitotrophe activity. The activity of bacteria colonies is known in various rocks and depths, mainly in the aquifer [Sinclair and Ghiorse, 1989 ; Stevens and McKinley, 1995]. The formation of the Mfoula cave is summarized as follow (fig. 5). Meteoric water is drained down along sub-vertical fractures and then along horizontal discontinuities of the foliation, particularly in case of lithological variations. Chemical and biological dissolution is working. Lateral transfers linked to the aquifer oscillations caused widening of the caves. Dissolved products are transported by the vertical drains. Regressive erosion of the valley, linked to the epeirogenic upwelling due to the volcano-tectonic activity of the Cameroon Line, makes the cavities come into sight at the valley flanks. Discussion and conclusion. - The two examples of the Guessedoundou and Mfoula caves evidence the reality of the karsts in non-carbonated silicated rocks. The karst term is used to design >> any features of the classical karst morphology (caves, dolines, lapies...) where dissolution plays the main genetical action >> [Willems, 2000]. Our observations indicate that (i) the karst genesis may have occurred into any kind of rocks, and (ii) the cave formation is not directly dependent of the present climate. These facts have major consequences to hydrogeological investigations, especially for water supply in Sahelian and sub-desertic countries. Some measurements of water transfer speed across either sedimentary pelitic strata of the Continental terminal or igneous rocks of the substratum in West Niger [Esteves and Lenoir, 1996 ; Ousmane et al., 1984] proved that supplying of aquifers in these silico-aluminous rocks may be as fast as in a karstic limestone. That means the West Niger substratum is highly invaded by a karstic net and may hidden a lot of discontinuous aquifers. The existence of this karst system can be easily shown by morphological observations, the same that are done in karstic limestone regions (abnormally suspended dry valleys, collapses, dolines...). Clearly, this must be the guide for any search of water, even in desertic areas where limestones are absent

Results 1 to 15 of 26
You probably didn't submit anything to search for