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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 loess is fine-grained and poorly consolidated windblown sediment, mainly of silt. great thicknesses of loess are found in areas marginal to hot and cold deserts, where the prevailing wind deposits fine dust particles blown from the desert basins or out of glaciofluvial sediments. loess is a common allogenic component of soils on limestones. large numbers of artificial caves have been excavated in the hillsides of soft loess in central china [9].?

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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 precambrian (Keyword) returned 43 results for the whole karstbase:
Showing 31 to 43 of 43
The influence of bedrock-derived acidity in the development of surface and underground karst: Evidence from the Precambrian carbonates of semi-arid northeastern Brazil, 2003, Auler As, Smart Pl,
Very extensive cave systems are developed in Precambrian Una Group carbonates in the Campo Formoso area, eastern Brazil. In contrast, the area is largely devoid of significant surface karst landforms, as would be expected given its semi-arid climate. The caves in the area display many morphological features characteristic of deep-seated hypogenic caves, such as lack of relationship with the surface, ramiform/network pattern, abrupt variations of passage cross-sections and absence of fluvial sediments, but do not show evidence of vertical passages marking the ascending path of acidic water nor present extensive gypsum or acid clay mineral deposits. Hydrochemical analyses of present-day ground water indicate that oxidation of bedrock sulphide is an active process, and sulphuric acid may be the main agent driving carbonate dissolution in the area. A shallow mode of speleogenesis is thus proposed, in which sulphuric acid produced through the oxidation of sulphide beds within the carbonates controls cave initiation and development. Moreover, the geological situation of the area in an ancient stable passive margin precludes the possibility of deep-seated sources of acidity. Under dry climate, due to the absence of recharge, solutional landforms will be largely subdued in the surface. Hypogenic processes, if present, are likely to predominate, producing a landscape characterized by a marked disparity in the comparative degree of development between surface and underground landforms. Rates of karst landform development have traditionally been analysed through a climatic perspective, runoff being the main controlling factor in promoting karst development. This view needs to be reassessed in the light of the growing awareness of the importance of climate-independent processes related to hypogenic sources of acidity.

Stratigraphic investigations of carbon isotope anomalies and Neoproterozoic ice ages in Death Valley, California, 2003, Corsetti Fa, Kaufman Aj,
An unusual richness of biogeochemical events is recorded in Neoproterozoic-Cambrian strata of the Death Valley region, California, United States. Eight negative carbon isotope ({delta}13C) excursions are found in carbonate units between 1.08 Ga and the Precambrian/Cambrian boundary; four of these excursions occur in carbonates that contain textural features similar to those found globally in postglacial 'cap carbonates' (including one or more of the following: laminite with rollup structures, apparent 'tube rocks,' seafloor precipitates, and sheet-crack cements). However, only two of these units, the Sourdough limestone member of the Kingston Peak Formation and the Noonday Dolomite, rest directly upon glacial strata. The basal Beck Spring Dolomite and the Rainstorm Member of the Johnnie Formation each contain negative excursions and cap-carbonate-like lithofacies, but do not rest on known glacial deposits. If the negative {delta}13C excursions are assumed to record depositional processes, two equally interesting hypotheses are possible: (1) The Death Valley succession records four glacial pulses in Neoproterozoic time, but glacial units are not preserved at two stratigraphic levels. (2) Alternatively, other global oceanographic processes can cause negative excursions and cap-carbonate-like facies in addition to, or independent of, glaciation

Fallen arches: Dispelling myths concerning Cambrian and Ordovician paleogeography of the Rocky Mountain region, 2003, Myrow Paul M. , Taylor John F. , Miller James F. , Ethington Raymond L. , Ripperdan Robert L. , Allen Joseph,
High-resolution sedimentologic, biostratigraphic, and stable isotope data from numerous measured sections across Colorado reveal a complex architecture for lower Paleozoic strata in the central Cordilleran region. A lack of precise age control in previous studies had resulted in misidentification and miscorrelation of units between separate ranges. Corrections of these errors made possible by our improved data set indicate the following depositional history. The quartz-rich sandstone of the Sawatch Formation was deposited during onlap of the Precambrian erosion surface in the early Late Cambrian. The overlying Dotsero Formation, a regionally extensive carbonate- and shale-rich succession records blanket-like deposition with only minor facies changes across the state. An extremely widespread, meter-scale stromatolite bed, the Clinetop Bed, caps the Dotsero Formation in most areas. However, a latest Cambrian erosional episode removed 9-11 m of the upper Dotsero Formation, including the Clinetop Bed, from just east of the Homestake shear zone in the Sawatch Range eastward to the Mosquito Range. The overlying Manitou Formation differs in character, and thus in member stratigraphy, on the east vs. west sides of the state. These differences were previously interpreted as the result of deposition on either side of a basement high that existed within the Central Colorado Embayment or Colorado 'Sag,' a region of major breaching across the Transcontinental Arch. This paleogeographic reconstruction is shown herein to be an artifact of miscorrelation. Biostratigraphic data show that the northwestern members of the Manitou Formation are older than the members exposed in the southeastern part of the state and that there is little or no overlap in age between the two areas. This circumstance is the result of (1) removal of older Manitou Formation strata in the southeast by an unconformity developed during the Rossodus manitouensis conodont Zone, and (2) erosion of younger Manitou strata in central and western Colorado along Middle Ordovician and Devonian unconformities. Deciphering these complex stratal geometries has led to invalidation of long-held views on western Laurentian paleogeography during the Cambrian and earliest Ordovician, specifically the existence of the Colorado Sag and a northeast-trending high within the sag that controlled depositional patterns on either side. The mid- Rossodus uplift and resultant unconformity eliminated any and all Upper Cambrian and Lower Ordovician deposits in southern Colorado and northern New Mexico, and thus their absence should not be misconstrued as evidence for earlier nondeposition in this region. Lithofacies distribution patterns and isopach maps provide no evidence that highlands of the Transcontinental Arch existed in Colorado prior to the mid-Rossodus age uplift event. In fact, regional reconstructions of earliest Paleozoic paleogeography along the entire length of the purported Transcontinental Arch should be reevaluated with similarly precise biostratigraphic data to reconsider all potential causes for missing strata and to eliminate topographic elements not supported by multiple stratigraphic techniques. This study illustrates how seriously paleogeographic reconstructions can be biased by the presumption that missing strata represent periods of nondeposition rather than subsequent episodes of erosion, particularly in thin cratonic successions where stratigraphic gaps are common and often inconspicuous

The unique Central Aldan gold-uranium ore district (Russia), 2004, Kazansky V. I. ,
In recent years, problems of the formation and distribution of ore deposits large and unique in their origin and scale have been discussed in publications and at international geological meetings. The aim of the present article is to show that not only individual deposits, but also ore districts may be unique. Such ore districts, for example, the Central Aldan gold-uranium ore district, contain deposits of various origins that belong to the same metallogenic epoch and were formed in similar geodynamic conditions. The Central Aldan gold-uranium ore district, with its resources of Au of 1000 t and U of 600000 t, is interpreted as a single unit. Its unique features are reflected at different levels: transregional, regional, and local. At the transregional level, its position is defined by the superposition of intense Mesozoic epicontinental tectonics, calc-alkaline-alkaline magmatism, and extensive hydrothermal ore mineralization on consolidated Early Precambrian structures of the Aldan Shield. In the Mesozoides of East Asia, Au and U deposits are located separately from each other except for in the Central Aldan district, where these deposits occur jointly and possess unique features. The interrelation between the Early Precambrian and the ore-bearing Mesozoic structures is clearly manifested in the Aldan Shield itself. The Central Aldan ore district is situated at the conjunction of the two largest megablocks, the Aldan-Timpton and Timpton-Uchur, which 2 Ga ago were transformed into a gneiss-granulite terrane. The Central Aldan district is confined to the periphery of a giant dome made up of Early Precambrian rocks of the Iengra complex. This district contains the largest and most varied subvolcanic caic-alkaline-alkaline intrusions. Finally, on the local scale, the Central Aldan magmatectonogen appears as the main ore-controlling factor. It consists of radial and ring faults cutting the crystalline basement and platform cover. It defines the distribution of Mesozoic magmatic rocks and various deposits in different radial blocks. The Central Aldan district contains three main types of ore deposits that form the following independent ore fields: the hydrothermal Au-U El'kon, the hydrothermal U Lebedinsk, and the polygenetic Au Kuranakh. The first and third deposits are unique not only in their scale, but in their origin as well. Deposits of the El'kon type are confined to rejuvenated faults of the crystalline basement and are characterized by exclusive extension of low-temperature Au-U mineralization. The third, Kuranakh type, in many respects enigmatic, is characterized by the presence of gold-bearing karst clays at the contact of platform limestones with Jurassic sandstones. The data presented in this article were accumulated during the 70-year history of the study and development of the Central Aldan district. Some deposits have been worked out and others preserved from operation due to different reasons. Many problems of the origin of ore deposits in the Central Aldan district have not yet been solved, and its total ore potential is far from being established

Fractured hydrothermal dolomite reservoirs in the Devonian Dundee Formation of the central Michigan Basin, 2006, Luczaj J. A. , Harrison Iii. W. B. , Williams N. S.

The Middle Devonian Dundee Formation is the most prolific oilproducing unit in the Michigan Basin, with more than 375 million bbl of oil produced to date. Reservoir types in the Dundee Formation can be fracture controlled or facies controlled, and each type may have been diagenetically modified. Although fracture-controlled reservoirs produce more oil than facies-controlled reservoirs, little is known about the process by which they were formed and diagenetically modified. In parts of the Dundee, preexisting sedimentary fabrics have been strongly overprinted by medium- to coarse-grained dolomite. Dolomitized intervals contain planar and saddle dolomite, with minor calcite, anhydrite, pyrite, and uncommon fluorite. Fluid inclusion analyses of two-phase aqueous inclusions in dolomite and calcite suggest that some water-rock interaction in these rocks occurred at temperatures as high as 120–150jC in the presence of dense Na-Ca-Mg-Cl brines. These data, in conjunction with published organic maturity data and burial reconstructions, are not easily explained by a long-term burial model and have important implications for the thermal history of the Michigan Basin. The data are best explained by a model involving short-duration transport of fluids and heat from deeper parts of the basin along major fault and fracture zones connected to structures in the Precambrian basement. These data give new insight into the hydrothermal processes responsible for the formation of these reservoirs. 


Le problme de louverture des vides initiaux pr-karstiques: cas de la dolomie siliceuse du Sous-Groupe de Malmani, Afrique du Sud., 2007, Martini J.
THE PROBLEM RELATED TO THE INITIAL SIZE OF THE PRE-KARSTIC VOIDS: THE CASE OF THE SILICEOUS DOLOSTONE OF THE MALMANI SUBGROUP, SOUTH AFRICA. The paper describes pre-karstic jointing in phreatic mazes developed in a Precambrian siliceous dolostone. The initial joint opening controling the speleogenesis can be measured in chert seams interstratified within the dolostone, since they are practically unaffected by karst dissolution. The measured openings generally vary from 0.3 to 5.0 mm, although values up to 30 mm have been recorded. The origin of the jointing has been linked to a Liassic tentional event which affected the entire African Austral sub-continent. This event is also associated with a major basaltic volcanism of the fissural type. Due to the exceptional nature of this tentionnal event, it appears difficult to compare the figures given here with the openings given by the authors from karst domains elsewhere in the world, who quote figures 1 to 2 magnitudes smaller.

Bhimbetka Caves, Madhya Pradesh, India, 2008, Waltham, Tony.
The Bhimbetka Hills in central India are made of Precambrian quartzitic sandstone and contain hundreds of small caves and rock shelters, with origins similar to those of other caves in quartzite. The caves are also notable for their wealth of Palaeolithic and Mesolithic paintings.

STYLES OF HYPOGENE CAVE DEVELOPMENT IN ANCIENT CARBONATE AREAS OVERLYING NON-PERMEABLE ROCKS IN BRAZIL AND THE INFLUENCE OF COMPETING MECHANISMS AND LATER MODIFYING PROCESSES, 2009, Augusto S. Auler

A significant proportion of the karst areas in Brazil develop over ancient cratonic or tectonically stable zones overlying Precambrian quartzites or Archaean crystalline basement (granite, gneiss, schist). In such settings, due to the low transmissivity and highly anisotropic nature of the bedrock, major groundwater flow of regional scale tends to be restricted, and diffuse ascending cross-formational flow into the carbonate is limited to a few favourable input zones. Nevertheless, caves displaying hypogene features occur in several areas, although few contain the full suite of speleogenetic forms commonly found in “classic” better studied areas of Europe and North America. Major known hypogene caves in Brazil tend to be located in zones bordering the more stable cratonic areas, such as in Vazante and Toca da Boa Vista karst areas, where fault zones are likely candidates for providing ascending flow paths towards the carbonate. The absence of transmissive beds above the carbonate limits the existence of outflow routes. Brazilian hypogene caves develop in mostly horizontally bedded or gently dipping bedrock and typically do not display the three-dimensional character of many hypogene caves elsewhere. The speleogenetic role of competing mechanisms such as sulphuric acid dissolution due to pyrite oxidation and condensation corrosion tend to overprint original forms as well as produce similar convergent features.


The Karst Mandhip Khol-python cave complex in the lenticular limestone intercalations of the matamorphic Chhatrela formation (Chhattisgarh, India), 2011, Ruggieri R. , Biswas J.

The Mandhip Khol-Pyton cave, located in an area declared Protected Forest in the Rajnandgaon District about 7 km in a direct line WNW from the village of Thakurtola (N21°39’:E080°58’), consists of an upper level orientated essentially along NE-SW and NNW-SSE fracture systems, subsequently connected through a NE-SW structure with an independent karst system, at a lower level orientated predominantly along bedding planes. The speleogenesis controlled by various structural elements has manifested itself as having different morphologies in the two levels. In fact, fracture-controlled vadose passages prevail in the upper level, while water flow along the bedding planes in the lower level has caused morphologies characterized by wide but low passages. The studied system constitutes a particular example of karst morphologies developed in a lenticular limestone formation within phyllite rocks of Precambrian metamorphic age.


Revisiting three minerals from Cioclovina Cave (Romania), 2011, Onac Bogdan P. , Effenberger Herta S. , Collins Nathan C. , Kearns Joe B. , Breban Radu C.

Cioclovina Cave in Romania’s Southern Carpathians is a world-renowned cave site for its paleontological, anthropological, and mineralogical (type locality of ardealite) findings. To date, over 25 mineral species have been documented, some unusual for a cave environment. This paper presents details on the occurrence of collinsite [Ca2(Mg,Fe2+)(PO4)2·2H2O], atacamite [Cu22+Cl(OH)3], and kröhnkite [Na2Cu2+(SO4)2·2H2O] based on single-crystal X-ray diffraction, electron microprobe, stable isotope analyses, and scanning electron microscope imaging. This is the first reported occurrence of kröhnkite in a cave environment. Atacamite represents the weathering product (in the presence of Lower-Cretaceous limestone-derived chlorine) of copper minerals washed into the cave from nearby ore bodies. Atacamite, and kröhnkite have similar sources for copper and chlorine, whereas sodium probably originates from weathered Precambrian and Permian detrital rocks. Collinsite is believed to have precipitated from bat guano in a damp, near-neutral pH environment. The results show the following sequence of precipitation: ardealite-brushite-(gypsum)-atacamite-kröhnkite. This suggests that the observed mineral paragenesis is controlled by the neutralization potential of the host-rock mineralogy and the concentrations of Ca, Cl, Cu, and Na.


Mineralogy of Iza Cave (Rodnei Mountains, N. Romania), 2011, Tă, Maş, Tudor, Kristly Ferenc, Barbutudoran Lucian

The secondary minerals from Iza Cave result from the interactions of karst water and/or cave atmosphere over a variety of sedimentary and metamorphic rocks. The cave passages expose at various extents Eocene limestones and conglomerates, Oligocene black shales, Upper Precambrian micaschists, marble and dolomitic marble and associated ore deposits.
Twelve secondary minerals identified in the cave (carbonates, sulfates, phosphates, oxides and hydroxides, and silicates) are presented in this study. Calcite, aragonite, gypsum, brushite and hydroxylapatite are the components of common speleothems in the limestone, dolomite and conglomerate areas of the cave. Ankerite crusts are related to areas with pyrite mineralization within the metamorphic carbonate rocks. Goethite, jarosite, hematite and gypsum form various speleothems in the sectors within micaschists and conglomerates. Large weathering deposits occurring in passage areas developed within micaschists consist of illite, kaolinite, jarosite, goethite, gypsum and alunite. The extent of the weathering deposits occurring on non-karst rocks in the underground environment makes this cave a particularly interesting site for studies of water-rock interactions.


Geographical and geological data from caves and mines infected with white-nose syndrome (WNS) before September 2009 in the eastern United States, 2011, Swezey C. S. , Garrity C. P.

Since 2006, a white fungus named Geomyces destructans has been observed on the muzzles, noses, ears, and (or) wings of bats in the eastern United States, and bat colonies that are infected with this fungus have experienced dramatic incidences of mortality. Although it is not exactly certain how and why these bats are dying, this condition has been named white-nose syndrome (WNS). WNS appears to have spread from an initial infection site at a cave that is connected to a commercial cave in New York, and by the end of August 2009 was identified in at least 74 other sites in the eastern United States. Although detailed geographical and geological data are limited, a review of the available data shows that sites infected with WNS before September 2009 include both natural caves and mines. These infected sites extend from New Hampshire to Virginia, and known site elevations range from 84 to 2693 feet above sea level. In terms of geological
setting, the infected sites include sedimentary, metamorphic, and igneous rocks of ages ranging from Precambrian to Jurassic. However, by the end of August 2009, no infected sites had been identified in strata of Mississippian, Cretaceous, or Triassic age. Meteorological data are sparse, but most of the recorded air temperatures in the known WNS-infected caves and mines range from 0 to 13.9 uC, and humidity measurements range from 68 to 100 percent. Although it is not certain which environmental parameters are
important for WNS, it is hoped that the geographical and geological information presented in this paper will inform and clarify some of the debate about WNS, lead to greater understanding of the environmental parameters associated with WNS, and highlight the paucity of scientific data from caves in the eastern United States.


Hypogenic origin, geologic controls and functional organization of a giant cave system in Precambrian carbonates, Brazil, 2015,

This study is focused on speleogenesis of the Toca da Boa Vista (TBV) and Toca da Barriguda (TBR), the longest caves in South America occurring in the Neoproterozoic Salitre Formation in the São Francisco Craton, NE Brazil. We employ a multidisciplinary approach integrating detailed speleomorphogenetic, lithostratigraphic and geological structure studies in order to reveal the origin of the caves, their functional organization and geologic controls on their development. The caves developed in deep-seated confined conditions by rising flow. The overall fields of passages of TBV and TBR caves represent a speleogenetically exploited large NE–SW-trending fracture corridor associated with a major thrust. This corridor vertically extends across the Salitre Formation allowing the rise of deep fluids. In the overall ascending flow system, the formation of the cave pattern was controlled by a system of sub-parallel anticlines and troughs with NNE–SSWdominant orientation, and by vertical and lateral heterogeneities in fracture distribution. Three cave-stratigraphic stories reflect the actual hydrostratigraphy during the main phase of speleogenesis. Cavities at different stories are distinct inmorphology and functioning. The gross tree-dimensional pattern of the system is effectively organized to conduct rising flow in deep-seated confined conditions. Cavities in the lower story developed as recharge components to the system. A laterally extensive conduit network in the middle story formed because the vertical flow from numerous recharge points has been redirected laterally along the highly conductive unit, occurring below the major seal - a scarcely fractured unit. Rift-like and shaft-like conduits in the upper story developed along fracturecontrolled outflow paths, breaching the integrity of the major seal, and served as outlets for the cave system. The cave system represents a series of vertically organized, functionally largely independent clusters of cavities developed within individual ascending flow cells. Lateral integration of clusters occurred due to hydrodynamic interaction between the flow cells in course of speleogenetic evolution and change of boundary conditions. The main speleogenetic phase, during which the gross cave pattern has been established and the caves acquired most of their volume, was likely related to rise of deep fluids at about 520 Ma or associated with rifting and the Pangea break-up in Triassic–Cretaceous. This study highlights the importance of speleogenetic studies for interpreting porosity and permeability features in carbonate reservoirs.


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