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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 cave group is a number of caves or cave systems, not interconnected but geographically associated in some relief feature or particular geological outcrop [10]. see also cave series.?

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

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KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
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 brazil (Keyword) returned 82 results for the whole karstbase:
Showing 76 to 82 of 82
Mycological study for a management plan of a neotropical show cave (Brazil)., 2013, Taylor E. L. S, Resendestoianoff M. A. A, Lopes Ferreira R.

Caves are stable environments with characteristics favoring the development of microorganisms. The allocthonous input of organic matter and microbes into the warm Neotropical caves may favor the development of filamentous fungi, including pathogenic species. Histoplasma capsulatum is a pathogenic species commonly found in caves and associated with bat and bird guano. Many Brazilian caves have been historically visited due to scenic and religious tourism. The objective of this study was to perform a microbiology study for a management plan of a show cave in Brazil, focusing on the presence and distribution of pathogenic and opportunistic fungi in the cave. Statistic analysis was used to verify the influence of touristic activity on airborne fungi spore load. Fungi were isolated from air and guano in Lapa Nova Cave. Samples were obtained through serial dilution, direct and settle plate techniques. For H. capsulatum, samples were incubated in specific media and conditions. Airborne fungal spore load was compared prior and during visitation and statistically analyzed. A total of 2,575 isolates from the genera Aspergillus, Calcarisporium, Chaetomium, Cladosporium, Curvularia, Emericella, Eurotium, Fusarium, Geotrichum, Gliocladium, Mucor, Purpureocillium, Paecilomyces, Penicillium, Rhizopus and Trichoderma were identified. Histoplasma capsulatum was not isolated from the cave. Eleven opportunistic species were identified. Significant (p<0.05) variations on fungal richness in the air occurred due to cave visitation. Areas of potential microbiologic risks were indicated and management actions suggested. The results suggest a diverse community inhabiting the cave. Possible opportunistic species should be monitored in show caves and microbiota should always be included in the elaboration of cave management plans. This is the first detailed microbiologic study for a management plan of a show cave in the country. It provides relevant information for future management plans.


Shape variation of Aegla schmitti (Crustacea, Decapoda, Aeglidae) associated to superficial and subterranean stream reaches, 2013, Camile Fernandes, Maria Bichuette

The species Aegla schmitti is relatively abundant in epigean streams in the Upper Ribeira Basin, southeastern Brazil and has a few records in caves. In this study, we questioned if those individuals would be an accidental presence or could be populations already established in cave streams? In this case, would morphological variations be associated with superficial and subterranean stream reaches? In this exploratory survey we tried to answer these questions by assessing the shape variation of cephalothorax using landmark-based geometric morphometrics. Different shapes were found for both environments, evidencing a successful hypogean colonization. The area effect was discarded as being the unique factor responsible for the divergence, therefore, for the first time in the literature, here we report morphological modifications associated with subterranean colonization in troglophiles. We also conceived and discussed some hypotheses about the colonization.


Aquatic biota of different karst habitats in epigean and subterranean systems of Central Brazil visibility versus relevance of taxa, 2013, Luiza Bertelli Simes, Tnia Cristina Dos Santos Ferreira, Maria Elina Bichuette

The karstic area of São Domingos, central Brazil, holds extensive drainage systems. In order to understand its biodiversity, various volumes of water were filtered with planktonic nets in stretches of subterranean and superficial rivers on five different occasions. We sampled four drips (152L), three calcite pools (368L), two subterranean rivers fed mainly by percolation water (6, 395L), two subterranean rivers fed mainly by water coming from a sinkhole (4, 175L) along different caves, one resurgence (158L), and four epigean rivers (101, 690L). Physical and chemical variables were measured at some sites. Canonical Correlation Analysis was used to verify relationships between taxa and environment. The degree of similarity of the biota was assessed by cluster analysis (Sorensen, single linkage). There were records of exclusive taxa in epigean and subterranean samples, mainly in drips, which harbour the most unique fauna. The high richness of taxa presently recorded reveals the potential of the vadose zone biota in the tropical region, which was neglected in studies on Brazilian subterranean biodiversity. According to our results, the unsaturated zone tropical fauna may have different composition compared to that from temperate habitats. The studied communities were dominated by rotifers, while crustacean are predominant in the latter. The hypothesis can be clarified with the increase of long term studies and taxa identification at species level, besides the use of complementary sampling methods.


PRELIMINARY CONSIDERATIONS ON HYPOGENE MORPHOLOGY IN TOCA DA BOA VISTA E TOCA DA BARRIGUDA CAVES, NORTHEASTERN BRAZIL, 2014, Borges S. , Casarin C. , Menezes C. , Srivastava N. , Silva R. , Bezerra F. , Auler A.

The Toca da Boa Vista and Barriguda caves are located in Northeastern Brazil. They occur in the Neoproterozoic carbonates (limestones and dolomites) of the Salitre Formation, located at Irecê Basin. This set of rocks occurs within the São Francisco Craton, a region that was not affected by the Brasiliano-Pan-African orogeny (Pedreira et al., 1987). The caves occur at a dis­tance of approximately 300 m apart and there is a possibility of a link between them, but so far this has not been proven. Toca da Boa Vista has about 108 km of mapped passages and is therefore the largest cave in South America. Toca da Barriguda is smaller and has about 32 km of mapped galleries.

The architecture of the Toca da Boa Vista and Barriguda caves present both a 2D network and spongework type (Auler, 2009). The control of the conduits is related to faults, fractures and axial planes of antiforms. The general configuration of the caves seems to follow the Pacuí riverbed that has its channel located about 1km southeast. The origin of these hypogenic caves was first postulated by Auler & Smart (2004), who described some hypogenic features and reported a acid source (H2S) coming from existing pyrite in carbonates to explain the corrosion and dissolution of carbonate rocks. Klimchouk (2009) wrote about the need to investigate deeper this issue. He drew attention to the apparent feeders presence coming from the lower aquifer as well as to the importance of determi­nation of the source of acidity, since the amount of pyrite present doesn’t seem to be significant for the origin and development of the caves by hypogenic speleogenesis.

Although the origin and development of the caves are still under discussion, abundant hypogenic forms are present. Feeders, rising wall channels, half ceiling tubes, half wall tubes, ceiling cupolas, convection cupolas and wall niches are the major forms found. The linear geometry of caves suggests that they have a structural control. In addition, cavities generated at Toca da Boa Vista and Barriguda caves seem to follow the same stratigraphic level, as well as existing permeable structures such as fractures, faults and axial planes of antiforms. The process of ascending flow through these structures has resulted in the opening of the cavities by hypogenic dissolution as well as the collapse of blocks caused by the lack of sustainability of the layers generated by the voids left by the dis­solution. Outlets that would flow to levels above were not found. The origin and evolution of the cave system, however, needs further investigation.


A conservation status index, as an auxiliary tool for the management of cave environments., 2014,

The conservation of the Speleological Heritage involves bioecological, geomorphological and anthropogenic studies, both from inside the caves and from the external environments that surround them. This study presents a method to rank caves according to their priority for conservation and restoration. Nine caves were evaluated: indicators related to the environmental impacts and the vulnerability status presented by those caves (intrinsic features) and the values scored in a ‘Cave Conservation Index’ (CCI) were established. We also used a rapid assessment protocol to measure cave vulnerability for prioritization of conservation/restoration actions (RAP-cr) comparing natural cavities with the same lithology, due to “strictu sensu” peculiarities. Based on the protocols applied in caves of the municipality of Laranjeiras, Sergipe, Northeastern Brazil, we concluded that the present method attended to the needs for the classification of the caves into categories of conservation/restoration status, using little time and financial effort, through rapid diagnostics that facilitate the comparisons. In this perspective, the CCI can be used to indicate areas that should be protected and caves that should be prioritized to have initiated activities of conservation and restoration.


Superposed folding and associated fracturing influence hypogene karst development in Neoproterozoic carbonates, São Francisco Craton, Brazil, 2015,

Porosity and permeability along fractured zones in carbonates could be significantly enhanced by ascending fluid flow, resulting in hypogene karst development. This work presents a detailed structural analysis of the longest cave system in South America to investigate the relationship between patterns of karst conduits and regional deformation. Our study area encompasses the Toca da Boa Vista (TBV) and Toca da Barriguda (TBR) caves, which are ca. 107 km and 34 km long, respectively. This cave system occurs in Neoproterozoic carbonates of the Salitre Formation in the northern part of the São Francisco Craton, Brazil. The fold belts that are around and at the craton edges were deformed in a compressive setting during the Brasiliano orogeny between 750 and 540 Ma. Based on the integrated analysis of the folds and brittle deformation in the caves and in outcrops of the surrounding region, we show the following: (1) The caves occur in a tectonic transpressive corridor along a regional thrust belt; (2) major cave passages, at the middle storey of the system, considering both length and frequency, developed laterally along mainly (a) NE–SW to E–W and (b) N to S oriented anticline hinges; (3) conduitswere formed by dissolutional enlargement of subvertical joints,which present a high concentration along anticline hinges due to folding of competent grainstone layers; (4) the first folding event F1was previously documented in the region and corresponds with NW–SE- to N–S-trending compression, whereas the second event F2, documented for the first time in the present study, is related to E–Wcompression; and (5) both folding  еvents occurred during the Brasiliano orogeny. We conclude that fluid flow and related dissolution pathways have a close relationship with regional deformation events, thus enhancing our ability to predict karst patterns in layered carbonates.


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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