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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 bifurcation ratio is the ratio of the number of stream segments of a given order to the number of segments of next higher order [16].?

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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 helictites (Keyword) returned 13 results for the whole karstbase:
Structure, Sediments and Speleogenesis at Cliefden Caves, New South Wales, 1978, Osborne, R. Armstrong L.

The Cliefden Caves have developed in the Late Ordovician Cliefden Caves Limestone mainly by solution in the phreatic zone. Speleogenesis has been inhibited in steeply dipping thinly bedded limestone and shows a high degree of structural control. Collapse has been significant in late stage development of the caves. Much sediment has been deposited in the four caves studied in detail - Main Cliefden, Murder, Boonderoo and Transmission. Formed in the phreatic zone, layered clay fill is the earliest sediment deposited and occurs in all but Transmission Cave. The phosphate mineral heterosite is found in these sediments. Subaqueous precipitation deposits deposited in the phreas or vadose pools are distinguished from speleothems by their texture. Aragonite is inferred to have been deposited in these sediments and to have since inverted to calcite. Friable loam and porous cavity fill are the most common vadose deposits in the caves. Vadose cementation has converted friable loam to porous cavity fill. Speleothem deposits are prolific in Main Cliefden, Murder and Boonderoo Caves. Helictites are related to porous wall surfaces, spar crystals result from flooding of caves in the vadose zone and blue stalactites are composed of aragonite. Cliefden Caves belong to that class proposed by Frank (1972) in which deposition has been more important than downcutting late in their developmental history.


Stalactites and Helictites of Marcasite, Galena, and Sphalerite in Illinois and Wisconsin, 1979, Peck, Stewart B

Sannur Cave: A Crescent shaped cave developed in Alabaster formation in Eastern Desert, Egypt, 1995, Gü, Nay G. , Elbedewy F. , Ekmekci M. , Bayari S. , Kurttas T.
An expedition to Egypt set out to explore the Wadi Sannur where no speleological work had taken place. The most notable karst feature identified to date is the Sannur Cave, the largest subterranean chamber known in Egypt. It is situated about 70 km to the southeast of Beni-Suef city in the remote Wadi Sannur of the Eastern Desert where the main rock units belong to Eocene and Pliocene periods. The Eocene is represented by limestone including alabaster which is known to be quarried first by the ancient Egyptians. Sannur Cave is first explored during blasting in the alabaster quarry which caused an artificial entrance to the cave. The cave is a single crescent shape chamber approximately 275 m long and can be arbitrarily divided into two sectionshaving different characteristics; left side gallery and right side gallery. Few speleothems occur in the left side gallery while the right side gallery is decorated intensively with many kinds of spelethem including stalagtites, stalagmites, flowstones, microgours, helictites and soda-straws etc. In addition to surveying the cave, based on the geologic, structural and morphologic observation inside and outside the cave some interpretations on the paleoenvironment an the origin of the cave. Surveying was performed with grade 5D according to BCRA Gradings.

La cristallogense des splothmes de la grotte Lithophagus (Monts Padurea Craiului, Roumanie), 1998, Ghergari Lucrecia, Onac Bogdan Petroniu, Vremir Matei, Strusievicz Robert
The Lithophagus cave system hosts interesting mono- and polycrystalline calcite speleothems (stalactites, stalagmites, crystals, helictites, fongites). Our studies allowed us to identify the crystallographic forms that build up these speleothems, the presence of twins and several generations of crystals. The main growth directions were identified for the helictites. The interpretation of the statistic data enables us to highlight the relationships between crystallographic forms that appear on some speleothems, their frequency, and the different cave environments.

The origin of tubular lava stalactites and other related forms., 1998, Allred Kevin, Allred Carlene
Tubular lava stalactites are often found in lava tubes. Field observations, sample analysis, and comparative studies indicate that these are segregations extruded during cooling from partially crystallized lava al about 1,070; 1,000 C. Retrograde boiling (gas pressure) within the lava provides a mechanism to expel the interstitial liquid. In addition to tubular lava stalactites, a variety of other lava features can also result, such as lava helictites, lava coralloids, barnacle-like stretched lava, runners, runner channels, and some lava blisters and squeeze-ups.

Ancient helictites and the formation of vadose crystal silt in upper Jurassic carbonates (Southern Germany), 1998, Reinhold C. ,
Speleothems and vadose crystal silt are effective indications for karstification processes in the fossil record. Upper Jurassic limestones in Southern Germany that have undergone vadose diagenesis contain on crystal margins and tips of coarse bladed calcites numerous fibrous calcite crystals, formed by abnormal growth conditions, and internal sediment within fractures and vugs, Fibrous calcite crystals grew as crusts, in fence and mesh-like arrangements. Fibrous crystals, which have a length:width ratio of greater than 1:10, are made up of stacked subcrystals composed of an alternation of hexagonal prisms and rhombohedra, They exhibit a central to somewhat eccentric capillary. Electron probe microanalysis shows low-Mg calcite mineralogy with negligible amounts of Fe, Mn, and Sr as well as dis seminated clay and metal hydroxide impurities. Stable-isotope data show relatively C-13-enriched and O-18-depleted values (delta(13)C similar to parts per thousand PDB, delta(18)O similar to -6 parts per thousand PDB), suggesting a meteoric environment and CO2 degassing as the main process of formation, Fibrous calcite crystals form from capillary fluids that are highly supersaturated with respect to calcium carbonate, contaminated with alien mineral impurities. The abnormal growth pattern is suggested to be substrate-controlled and attributed to mineral impurities that produce numerous crystallization nuclei. Fibrous calcite crystals are comparable to helictites of the filiform type that are reported only from Quaternary caves. Nevertheless, the diagenetic sequence and oxygen isotope data suggest a Late Cretaceous to early Tertiary age for their formation. The internal sediment consists exclusively of silt-size fragments of fibrous crystals and therefore is comparable to vadose crystal silt. Crystal silt is generated by the erosion of fibrous crystals both by va dose seepage and air currents. This study is the first observation of ancient helictites and related vadose crystal silt, documenting the close relationship between pore ceiling vadose cements and the generation of crystal silt

Ribbon helictites: a new category, 1999, Rowling, Jill

Describes the size, shape, abundance and location of ribbon helictites and proposes possible growth mechanisms for them. SEM photographs of surface of a ribbon helictite show an unusual crystal form for a calcite speleothem, together with apparent etching and pitting of surfaces. These surfaces exhibit some features found in organically deposited calcite. Further optical work revealed that stem of ribbon helictites is composed of a twinned pair of crystal aggregates, with stem's central canal lying in this twin plane. The ribbon also appears to exhibit twinning. Oval features on ribbon's surface appear to be twinned aggregates, originating from ribbon's central canal. It is proposed that ribbon helictites form by two growth stages: development of stem and then a ribbon, with influences from acidic solutions. Overall shape is strongly controlled by crystal habit.


Extraordinary Features of Lechuguilla Cave, Guadalupe Mountains, New Mexico, 2000, Davis, D. G.
Many unusual features are displayed in Lechuguilla Cave, Guadalupe Mountains, New Mexico, U.S.A. Early speleogenic features related to a sulfuric acid origin of the cave include acid lake basins and subterranean karren fields. Speleogenetic deposits, also products of sulfuric acid origin, include gypsum glaciers and sulfur masses. Features related to convective atmospheric phenomena in the cave include corrosion residues, rimmed vents, and horizontal corrosion/deposition lines. Speleothems of nonstandard origin include rusticles, pool fingers, subaqueous helictites, common-ion-effect stalactites, chandeliers, long gypsum hair, hydromagnesite fronds, folia, and raft cones. Other unusual features discussed are silticles and splash rings.

Wurmfrmige Excentriques mit ungewhnlichem Calcitgefge - Untersuchungen mit der Elektronen-Rckstreu-Beugungs-Methode, 2007, Richter D. K. , Neuser R. D.
Vermiform helictites (excentriques) from a former side branch of the Breitscheid-Erdbach cave are frequently polycrystalline and not composed of a single calcite crystal. The electron backscatter diffraction (EBSD)-technique reveals a lath-shaped calcite structure with c-axes oriented nearly parallel to the elongation of the helictites. The resulting structure of the helictites is a calcite fibre bundle diverging along the growth direction. Three equivalent symmetrical sectors can be distinguished. The maximum deviation from the elongation is 18 and occurs at the exterior in the centre of the segments of the excentriques. The complex internal structure and the conical shape of the tip of the excentriques suggest a special kind of calcite precipitation, whereby biofilms seem to have played a significant role.

Secondary halite deposits in the Iranian salt karst: general description and origin, 2011, Filippi Michal, Bruthans Jiř, , Palatinus Luk, Zare Mohammad, Asadi Naser

This paper summaries 12 years of documentation of secondary halite deposits in the Iranian salt karst.
A variety of secondary halite deposits was distinguished and classified into several groups, on the basis of the site and mechanism of their origin. Deposits formed: i) via crystallization in/on streams and pools, ii) from dripping, splashing and aerosol water, iii) from evaporation of seepage and capillary water, and iv) other types of deposits. The following examples of halite forms were distinguished in each of the above mentioned group: i) euhedral crystals, floating rafts (raft cones), thin brine surface crusts and films; ii) straw stalactites, macrocrystalline skeletal and hyaline deposits, aerosol deposits; iii) microcrystalline forms (crusts, stalactites and stalagmites, helictites); iv) macrocrystalline helictites, halite bottom fibres and spiders, crystals in fluvial sediments, euhedral halite crystals in rock salt, combined or transient forms and biologically induced deposits. The occurrence of particular forms depends strongly on the environment, especially on the type of brine occurrence (pool, drip, splashing brine, microscopic capillary brine, etc.), flow rate and its variation, atmospheric humidity, evaporation rate and, in some cases, on the air flow direction. Combined or transitional secondary deposits can be observed if the conditions changed during the deposition. Euhedral halite crystals originate solely below the brine surface of supersaturated streams and lakes. Macrocrystalline skeletal deposits occur at places with rich irregular dripping and splashing (i.e., waterfalls, places with strong dripping from the cave ceilings, etc.). Microcrystalline (fine grained) deposits are generated by evaporation of capillary brine at places where brine is not present in a macroscopically visible form. Straw stalactites form at places where dripping is concentrated in small spots and is frequent sufficient to assure that the tip of the stalactite will not be overgrown by halite precipitates. If the tip is blocked by halite precipitates, the brine remaining in the straw will seep through the walls and helictites start to grow in some places.
Macrocrystalline skeletal deposits and straw stalactites usually grow after a major rain event when dripping is strong, while microcrystalline speleothems are formed continuously during much longer periods and ultimately (usually) overgrow the other types of speleothems during dry periods. The rate of secondary halite deposition is much faster compared to the carbonate karst. Some forms increase more than 0.5 m during the first year after a strong rain event; however, the age of speleothems is difficult to estimate, as they are often combinations of segments of various ages and growth periods alternate with long intervals of inactivity.
Described forms may be considered in many cases as the analogues of forms found in the carbonate karst. As they are created in a short time period the conditions of their origin are often still visible or can be reconstructed. The described halite forms can thus be used for verification of the origin of various carbonate forms. Some of the described forms bear clear evidence of the paleo-water surface level (transition of the skeletal form to halite crystals and vice versa). Other kinds of deposits are potential indicators of the microclimate under which they developed (humidity close to the deliquescence relative humidity).


Black Mn-Fe Crusts as Markers of Abrupt Palaeoenvironmental Changes in El Soplao Cave (Cantabria, Spain), 2011, Gzquez Fernando, Calaforra Jose Maria, Forti Paolo

Peculiar iron and manganese deposits coating walls, floors and ceilings of many galleries are one of the special features of the El Soplao Cave (Cantabria, Spain). These speleothems appear to have been deposited over wall clay deposits, as well as forming part of flowstones. Structure of crusts is essentially amorphous but several manganese and iron oxides were identified like goethite and birnessite, though all occur with a low degree of crystallinity. In the outer layer of the crusts, alteration iron minerals appear that derive from previous minerals in a process probably mediated by microorganisms. EDX microanalyses report fairly high values of Fe and Mn in the crusts, though the Mn/Fe ratio varies considerably as a function of distance from the substrate/bedrock. The present study proposes a genetic model for crust speleothems in El Soplao, based on oscillations of the phreatic level. The origin of these deposits is related to mobilization, under phreatic conditions, of polymetallic sulfides in the host rock. Metal ions (including Fe²⁺ and Mn²⁺) released into the cave under reducing conditions, are oxidized and fixed in a process mediated by bacteria, giving rise to oxides and hydroxides of low crystallinity. The presence of various black intercalated layers in aragonite flowstones indicate periods when cave conditions suddenly changed from vadose, when aragonite is precipitated, to phreatic and epiphreatic conditions, when the Mn-Fe deposits are precipitated. Subsequently, vadose conditions were re-established, leading to the final stages of precipitation of aragonite recorded in the flowstone and recent aragonite helictites on the surface of the Mn-Fe crusts.


Speleothems: General Overview, 2012, White, William B.

Speleothems are secondary mineral deposits formed in caves by flowing, dripping, or seeping water. The most commonly occurring minerals are calcite, aragonite, and gypsum although many other minerals have been found in speleothems. The shapes of speleothems are determined by a competition between the dynamics of the water and the crystal growth habits of the constituent minerals. Stalactites, stalagmites, flowstone, and other speleothems deposited from dripping for flowing water take shapes dictated by the details of the flow behavior. Helictites, anthodites, and gypsum flowers formed from seeping water and various pool deposits take shapes dictated by the habit of crystal growth. Tan, orange, and brown colors common to calcite speleothems and also their luminescence under ultraviolet light is due to inclusion of humic and fulvic acid from overlying soils. Speleothems are also found in lava tubes.


Microbial mediation of complex subterranean mineral structures, 2015, 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

Helictites—an enigmatic type of mineral structure occurring in some caves—differ from classical speleothems as they develop with orientations that defy gravity. While theories for helictite formation have been forwarded, their genesis remains equivocal. Here, we show that a remarkable suite of helictites occurring in Asperge Cave (France) are formed by biologically-mediated processes, rather than abiotic processes as had hitherto been proposed. Morphological and petro-physical properties are inconsistent with mineral precipitation under purely physico-chemical control.

Instead, microanalysis and molecular-biological investigation reveals the presence of a prokaryotic biofilm intimately associated with the mineral structures. We propose that microbially-influenced mineralization proceeds within a gliding biofilm which serves as a nucleation site for CaCO3, and where chemotaxis influences the trajectory of mineral growth, determining the macroscopic morphology of the speleothems. The influence of biofilms may explain the occurrence of similar speleothems in other caves worldwide, and sheds light on novel biomineralization processes.


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