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KarstBase a bibliography database in karst and cave science.
Featured articles from Cave & Karst Science Journals
Characterization of minothems at Libiola (NW Italy): morphological, mineralogical, and geochemical study, Carbone Cristina; Dinelli Enrico; De Waele Jo
Chemistry and Karst, White, William B.
The karst paradigm: changes, trends and perspectives, Klimchouk, Alexander
Long-term erosion rate measurements in gypsum caves of Sorbas (SE Spain) by the Micro-Erosion Meter method, Sanna, Laura; De Waele, Jo; Calaforra, José Maria; Forti, Paolo
The use of damaged speleothems and in situ fault displacement monitoring to characterise active tectonic structures: an example from Zapadni Cave, Czech Republic , Briestensky, Milos; Stemberk, Josef; Rowberry, Matt D.;
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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In this note, which results from a paper published in France, the author defines the "karst system" formed by several successive levels, at the heart of a limestone mass: joints of surface feeding, vertical chimneys, galleries which are alternatively dry and full of water according to the season, a network of continually drowned clefts. He then studies modifications in this system resulting from internal causes, corrosion, filling and sedimentation, concretion. Then he shows how this evolution of the karst system may be modified by general conditions: geology, tectonics, geography with the losses, resurgences and the role of surface formations. The deepening of the river level may create a structure of differing levels in the various karst system, but their positioning is always slower than the streams erosion and it comes about later. In any case, the caves in a dried karst system undergo an evolution on their own. Finally, the author gives the definition of the terms used to explain the evolution in the karst system: "embryonic galleries" in the network of clefts, "young galleries" in the zone which is alternately wet and dry, "mature galleries" where the concretion and the erosion are balanced, "old galleries" where the concretion is becoming more and more important, "dead galleries" where the cave is completely filled by the deposits and concretions. This classification will easily replace the inexact terms of "active galleries" and "fossilized galleries" which are too vague and lead to confusion.
The present note calls into question the opinion of different authors concerning the presence or lack of adult Niphargus near the phreatic table (superior layer of phreatic water) in zones prospected by Karaman-Chappuis method. Our investigations have proved the reason for which Niphargus adults were less frequent in the superior layer of the phreatic water is rather concerned with our investigation means; which are very approximate -, than with the ecological or ethological requirements of these animals. The assertion that the phreatic fauna performs downward migrations during the floods must be considered as doubtful. During floods it is impossible to dig into the alluvial deposits immediately near the stream, these being completely flooded; so, we are obliged to dig in regions more distant from the riverside, which are not flooded. It is well known that in this zone the biocoenosis contains always a greater number of phreatobius elements. One of the authors (C. Motas) introduce the terms: rithrobios; for the fauna inhabiting the epigean streams, phreatobios; for that inhabiting the phreatic water, and geobios; for the terrestrial world.
Zinc occurs in low-iron sphalerite associated with gangue dolomite in dissolution breccias and collapse structures in dolomitized limestone and interbedded fine-grained 'primary' dolomite. These breccias and collapse structures were developed as part of a karst-sinkhole complex formed at depths up to 800 feet below the top of the Knox Dolomite during widespread emergence at the end of Early Ordovician time. Mineralization was completed before the rocks were tilted, and clearly antedates the Appalachian orogeny. Source of hydrothermal solutions is not known
The clustering areas of bent-winged bats in limestone caves are frequently stained and etched. This staining is very intense, and covers large areas at breeding caves present in Palaeozoic limestones. Erosion of limestone is very conspicuous in these caves. Staining is not intense at breeding caves in Tertiary limestones, but a combination of chemical and mechanical erosion may, in part, account for the depth of dome pits in which the bats cluster. Certain caves that are characterised by extensive guano deposits and by conspicuously eroded and/or stained limestone, but which are currently without large colonies of bats, may represent ancestral breeding caves.
Bauxite deposits are formed on karst topography because the sinkholesentrap aluminous materials subject to laterization. In the Jamaican deposits, these primary aluminous materials are mainly residuum from the White Limestone Formation, but may include some volcanic ash. In the Eufaula deposits, the source materials were kaolinitic claysderived from weathering of crystalline rocks of the Piedmont. The sinkholes provide downward drainage, and deposits formed in them are protected from erosion
Some physical data collected over a period of a year in seven locations of the Ogof Ffynnon Ddu cave system in South Wales are reported, including humidity, air and water temperature, pH of the water, as well as the organic oxygen demand of the water. It is shown that seasonal variations in the physical constant in this particular cave system are not well marked. Algae and bacteria were isolated from the soil samples and from calcareous deposits. A total of 30 algal species, of which 13 belong to the Cyanophyta, 22 to the Chlorophyta, and 7 to the Chrysophyta~Baccilariophyceae were found. Thirty-eight heterotrophic and 7 autotrophic bacteria were isolated. The thin films on water surfaces, besides diatoms, contained several flagellates and some ostracods, while some protozoa were found associated with the bacteria and algae in the soft calcite deposits.
Halite has been found in five caves on the Nullarbor Plain, Western Australia. It occurs as stalactites, stalagmites, crusts, or fibres. The climate of the plain is arid to semi-arid, and the halite is derived from wind-blown salts that accumulate in the soil. The halite forms in the caves under conditions of relatively low humidity (about 70%) and high temperature (about 67°F). Its association with older calcite deposits suggests the climate was once wetter or cooler than at present.
Information on the extinct "cave goat" (Myotragus balearicus Bate 1909) of the Balearic Islands is reviewed. Abundant remains of Myotragus balearicus are known from various deposits of late Quaternary (including Regent) ages. It had only a single pair of lower incisors, in this respect resembling Australian herbivorous marsupials, especially the bare nosed wombats.
A geomorphological study of the east coast of Andros (Fresh Creek area) shows the existence of a paleotopography represented by low-altitude hills (few metres). This paleotopography is protected by the presence of a calcitic Quaternary crust which covers Pleistocene calcarenite.In the western part of the area, there are long woody axes, oriented NE-SW, parallel to the channels of the creek. They end at two kilometres from the coast, along which is a second kind of lower hills, orthogonal to the first.The first axes can be interpreted as megaripples as seen at the present time on modern deposits (on the Great Bahama Bank) and fossilized by the upper crust. The second direction is made by accretion ripples along the coast.The surface of the Bahamian calcarenite has been studied. The Bahamian karst presents two topographical forms: “blue holes” like those outside the island, which are 60-80 m in diameter and both sparse and deep; and “washtub” dolines; these are numerous and shallow, and, from low altitude, exhibit a honeycombed aspect on the surface. This karstic topography with dolines and blue holes is also seen through the water of the Creek the hard bottom of which is covered only here and there with a few centimetres of sediments. Hence, there is a submerged karstic topography, made of the same elements as the aerial karst, but submerged by the Holocene transgression. The present karstic relief, in relation with the different eustatic levels of the Quaternary, has begun 120,000 years ago, according to the isotopic ages, and might be composed by different steps, difficult to show now, in the topography.The blue holes in the interior of the island of young and little evolved karst, were formed more by solution than by collapse of the karstic caves, because of the absence of a real river to drain the Andros shelf at the time of low sea levels. Blue holes of the inside of the island, as they are called, with submarine openings, have the same salinity as the water of the creek (17.5 g/l). The dolines with very low salinity (0.7 g/l to 3.8 g/l) are filled with stromatolites and charophytes, slowly forming sediments made up essentially of high-magnesian calcite.It seems that the Andros Island karst can be compared with that of the Yucatan, where there are round and deep open pits, called cenote, of which the Bahamian equivalent would be the blue holes which were drowned by the Holocene transgression.ResumeSur l'ile Andros, zone emergee du Grand Banc de Bahama, l'auteur montre l'existence d'une paleotopographie comprenant deux categories de rides d'orientation differente et semblant fossilisee par une croute calcitique recente et l'existence d'un karst aux formes jeunes, bien qu'heritage d'un karst holocene en voie de submersion. Ces formes sont des “blue holes” ou trous bleus circulaires (60 a 80 m de diametre) et peu nombreux, et des dolines, dites en baquet. Dans ces dolines se deposent actuellement des croutes stromatolithiques calcitiques dont l'etude est faite par diffractometrie de rayons X et microscopie electronique a balayage
The sedimentary history of the Walli Caves began with the deposition of finely laminated clay during the latter part of bedrock development in the phreatic zone. After aeration and entrance development, entrance facies accumulated, and this was followed by the deposition of large amounts of fluvial and lacustrine deposits. Episodic fluvial erosion of these deposits then took place, and flowstone was formed extensively during periods between each active erosion phase to produce a striking sequence of suspended flowstone sheets.
An old guano pile deposited by Macroderma gigas has been examined chemically and mineralogically. Sixteen sectional analyses of a profile are presented and discussed. The main soluble components are P2O5, CaO and SO3 (present as brushite, ardealite, gypsum and collophane) with insoluble quartz. Taranakite occurs as a minor constituent.
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