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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 slickenside is 1. a polished, commonly striated rock surface within a fault plane, produced due to friction during fault movement. the striae give an indication of the fault movement direction [9]. 2. a polished fault plane with grooves due to relative motion of fault blocks [16].?

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

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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 travertines (Keyword) returned 23 results for the whole karstbase:
Showing 16 to 23 of 23
Palaeoenvironments in semi-arid northeastern Brazil inferred from high precision mass spectrometric speleothem and travertine ages and the dynamics of South American rainforests, 2004, Auler A. S. , Wang X. , Edwards R. L. , Cheng H. , Cristalli P. S. , Smart P. L. , Richards D. A.

Understanding past environmental changes in tropical rainforests is extremely important in order to assess the response of such environments to present and future climatic changes and understand causes and the present patterns of biodiversity.
Earlier hypothesis on the origin of biodiversity have stressed the role of past climatic changes in promoting speciation. According to the “refuge hypothesis” (Haffer, 1982), dry periods could have led to forest fragmentation, isolating more humid forested zones (called refuges) within an environment largely dominated by savannas. The refuge hypothesis does not assign timescales for rainforest fragmentation, although recent studies have suggested that speciation could have occurred over timescales of millions of years (Knapp and Mallet, 2003). Although the focus of heavy criticism (Colinvaux, et a., 2000), the refuge hypothesis has generated a large amount of research. In general, pollen studies (Colinvaux, et a., 1996, Haberle and Maslin, 1999) tend to support a continuous forest cover throughout late Quaternary climatic shifts, although large variations in rainfall have also been demonstrated by other pollen and isotopic studies (van der Hammen and Absy, 1994; Maslin and Burns, 2000).
Amazon and Atlantic rainforests are the two major forested zones in South America. Amazon rainforest, the largest rainforest in the world, comprise a total original area of 4.1 million km2 and is renowned for hosting the large biodiversity in the world (30% of all the world’s known plant and animal species). Atlantic rainforest, also a biodiversity hotspot, occurs along the coast and has been subjected to heavy deforestation since European arrival. Nowadays only c. 7% of its original forested area of 1.3 million km2 remains. These two rainforests are separated by drought-prone semi-arid northeastern (NE) Brazil. Our study does not address the refuge hypothesis directly although it sheds new light on the dynamics of forest expansion in the past as well as indicates alternative ways of promoting speciation. It has long been hypothesized, due to botanical (Mori, 1989; Andrade-Lima, 1982) and faunistic (Costa, 2003) similarities, that the Amazon and Atlantic rainforests were once linked in the past. Although numerous connecting routes have been postulated (Bigarella, et al, 1975; Por, 1992; De Oliveira, et al, 1999), the timing of forest expansion and their possible recurrence have remained elusive.
The study area lies in the driest portion of NE Brazil “dry corridor”, close to the village of Laje dos Negros, northern state of Bahia. Mean annual precipitation is around 480 mm and potential evapotranspiration is in excess of 1,400 mm/year (Fig.1). Present vegetation comprises a low arbustive scrubland known locally as caatinga. The area contains a well-developed underground karst (Auler and Smart, 2003) with abundant secondary calcite precipitates, both underground (speleothems) and on the surface (travertines).


Cyclic sedimentation in Brazilian caves: Mechanisms and palaeoenvironmental significance, 2009, Auler Augusto S. , Smart Peter L, Wang Xianfeng, Piló, Luí, S B. , Edwards Lawrence, Cheng Hai

Caves associated with doline slopes in the tectonically stable area of eastern Brazil display remarkable sequences of clastic sediment intercalated with calcite layers. Sediment erosion has also occurred allowing access to formerly sediment-filled passages. The palaeoenvironmental meaning and chronology of these three processes (i.e. clastic sediment input, clastic sediment erosion, and speleothem precipitation) were studied in both semi-arid Campo Formoso and sub-humid Lagoa Santa areas through 230Th dating and stratigraphical analyses. The dry climate of the Campo Formoso area prevents speleothem deposition at present, but soil erosion results in valley aggradation and cave infilling. Growth periods of speleothems and travertines in this area have allowed the recognition of recurrent past phases of increased humidity correlated with wet conditions recorded in southeastern Brazil speleothem calcite. At the Lagoa Santa area there is limited speleothem precipitation and sediment input at present. However, sediment entrainment is actively exhuming speleothems and exposing cave passages. Sediment erosion inside caves in the area is interpreted as being due to intermediate climatic conditions, not wet enough to favour speleothem deposition and not too dry to allow doline slope erosion and sediment transport into caves.
Due to the low rates of denudation and isostatic rebound inherent to tectonically stable areas, cave passages will remain within the range of sediment infill and erosion for a much longer time than in tectonically active areas spanning, in average, at least three full glacial–interglacial cycles. As uplift proceeds, cave passages will be decoupled from the doline bottom and no longer will be affected by erosion or infilling episodes. Sediment filled passages in many caves in the Lagoa Santa region are relict features that display ancient clastic and chemical precipitation. The three processes described above have occurred throughout the life history of the caves, resulting in complex sediment assemblages that can, however, show significant intra- and inter-site variations.


INVESTIGATIONS ON FRESHWATER LIMESTONES FROM THE CARPATHIAN-BASIN: PALAEOCLIMATOLOGICAL AND SEDIMENTOLOGICAL STUDIES, 2009, Kele, S.

The sulfidic thermal caves of Acquasanta Terme (central Italy), 2010, Galdenzi S. , Cocchioni F. , Filipponi G. , Morichetti L. , Scuri S. , Selvaggio R. , And Cocchioni M.

The caves of Acquasanta Terme (central Italy) open at the core of a wide anticline, in the valley of the Tronto River. Cave development is due to the rise of sulfidic thermal water flowing through a thick marine limestone sequence, overlain by thick, low- permeability formations. Some minor caves are developed in the terraced travertines deposited by the thermal water, but the major caves are developed in marine limestone in the small gorge of the Rio Garrafo stream, a tributary of the Tronto River. These caves have a rising pattern, due to the past flow of thermal water toward the surface. The deepening of the Tronto River Valley lowered the regional water table, perching the Rio Garrafo stream ,50 m above the thermal groundwater. At present, surface water sinks through the pre-existing karst passages to reach the thermal water flowing in the lower parts of the caves. Where these waters mix, rapid corrosion of the walls through sulfuric acid speleogenesis occurs. Annual temperature and chemistrymonitoring of the cave water showed that freshwater contributes up to 45% of the volume at the water table. Dilution events are associated with falling water temperature, which ranges between 44uC and 32uC. At the main spring, 2 km downstream, groundwater dilution was higher resulting in lower temperatures (32uC–21uC) and salinity. The periods of high freshwater dilution correspond with a lowering of pHin the phreatic water and with the release ofH2S and CO2 to the cave atmosphere. In the thermal zones, the concentration of H2S increased from 40 to over 240 ppm, while CO2 increased from 0.44% to 2.7%. These data evidence the influence of sinking surface water on the cave environment and speleogenesis.


Empirical equations for the temperature dependence of calcite-water oxygen isotope fractionation from 10 to 708C, 2010, Demeґny A. , Kele S. , Sikloґsy Z.

Although the temperature dependence of calcite-water oxygen isotope fractionation seems to have been well established by numerous empirical, experimental and theoretical studies, it is still being discussed, especially due to the demand for increased accuracy of paleotemperature calculations. Experimentally determined equations are available and have been verified by theoretical calculations (considered as representative of isotopic equilibrium); however, many natural formations do not seem to follow these relationships implying either that existing fractionation equations should be revised, or that carbonate deposits are seriously affected by kinetic and solution chemistry effects, or late-stage alterations. In order to test if existing fractionation-temperature relationships can be used for natural deposits, we have studied calcite formations precipitated in various environments by means of stable isotope mass spectrometry: travertines (freshwater limestones) precipitating from hot and warm waters in open-air or quasi-closed environments, as well as cave deposits formed in closed systems. Physical and chemical parameters as well as oxygen isotope composition of water were monitored for all the investigated sites. Measuring precipitation temperatures along with oxygen isotope compositions of waters and calcites yielded empirical environment-specific fractionation– temperature equations: [1] 1000 _ lnaј17599/T – 29.64 [for travertines with a temperature range of 30 to 70-C] and [2] 1000 _ lnaј17500/T – 29.89 [for cave deposits for the range 10 to 25-C]. Finally, based on the comparison of literature data and our results, the use of distinct calcite-water oxygen isotopic fractionation relationships and application strategies to obtain the most reliable paleoclimate information are evaluated.


Collapse sinkholes distribution in the carbonate massifs of central and southern Apennines, 2011, Santo Antonio, Ascione Alessandra, Del Prete Sossio, Di Crescenzo Giuseppe, Santangelo Nicoletta

This study focuses on karst collapse sinkholes of the southern and central Apennines region (Italy), and has the aim of outlining and discussing the factors which contribute to the occurrence of collapse phenomena. By the analysis of the morphometrical/morphological features of the about 600 initially identified sinkholes, about 50% were interpreted as collapse sinkholes related to karst phenomena, which are the object of this study. These were geo-referred and organised in a data base, in which information on the geological-structural and hydrogeological features of areas affected by the collapses was also reported. The collapse sinkhole inventory was paralleled by an analysis of the distribution of the main mineral springs (H2S- and CO2- rich waters), of travertine bodies and of extensional faults with late Quaternary activity, which were all considered significant to the study due to the interrelations linking travertines, karst solution processes, CO2- rich waters and faults. Furthermore, with the aim of investigating the role of seismic shaking in the occurrence of the collapses, the karst collapse sinkhole distribution was compared with the distribution of stronger historical earthquake epicentres. The results of this regional scale synthesis suggests a possible key to the interpretation of karst collapse phenomena. The latter, in fact, appear correlated to the combination of peculiar conditions, which may be envisaged in the presence of active faults and mineral waters. The study, in particular, suggests that karst collapse sinkholes result from enhanced dissolution phenomena related to the rising of fluids of deep origin, for which active faults represent preferred pathways, and favoured by the presence
of a relatively shallow water table. In the collapse events,
an important role is possibly played by seismic shaking


SPELEOGENESIS ALONG DEEP REGIONAL FAULTS BY ASCENDING WATERS: CASE STUDIES FROM SLOVAKIA AND CZECH REPUBLIC, 2012, Bella Pavel, Bosak Pavel

The most conspicuous six examples illustrating ascending (perascensum) speleogenesis linked with deep faults/fault systemswere selected from Slovakia and Czech Republic. In the past,the caves have been described as product of phreatic, epiphreaticand vadose speleogenesis related to the evolution of localwater courses and valley incision, and linked mostly with Pleistocenegeomorphic evolution. Our analysis illustrates severalcommon characteristics of caves: (1) they developed along or inclose vicinity of deep faults/fault zones, commonly of regionalimportance; (2) the groundwater ascended due to deep faults/fault systems mostly as results of deep regional circulation ofmeteoric waters from adjacent karst or nonkarst areas; (3) the3D mazes and labyrinths dominate in cave morphology; (4)speleogens (e.g., cupolas, slots, ceiling channels, spongework,rugged phreatic morphology especially along slots) indicateascending speleogenesis in deep phreatic to phreatic environments;(5) they exhibit poor relation to the present landscape;in some of them fluvial sediments are completely missing inspite of surface rivers/streams in the direct vicinity; (6) strongepiphreatic re-modelling is common in general (e.g., subhorizontalpassages arranged in cave levels, water-table flat ceilingsand notches) and related to the evolution of the recent landscape;(7) recharge structures and correlate surface precipitatesare poorly preserved or completely missing (denuded) on thepresent surface in spite of fact that recent recharges broadlyprecipitate travertines; (8) caves can be, and some of them are,substantially older than the recent landscape (Pliocene, Miocene),and (9) caves were formed in conditions of slow water ascent, which differentiate the process from faster vauclusianascending speleogenetical models. Any of described caves containsclear diagnostic features of real hypogene caves. There aremissing evidences that at least heated groundwaters took partduring speleogenesis of studied caves, nevertheless, somewhatincreased water temperature can be expected during speleogenesisat least in some of caves. Any of described caves cannotbe directly characterized as product of thermal waters or hydrothermalprocess (i.e. as real hyperkarst sensu Cigna 1978),therefore they do not represent hypogenic caves.


PERMIAN HYDROTHERMAL KARST IN KRAKÓW REGION (SOUTHERN POLAND) AND ITS PECULIAR INTERNAL SEDIMENTS, 2014, Gradziński M. , Lewandowska A. , Paszkowski M. , Duliński M. , Nawrocki J. , Żywiecki M.

The development of caves influenced by the deep circulation of water has received increasing interest for the last thirty years. Presently, hypogene caves have been recognized all around the world. Conversely, the ancient examples filled with sediments and representing palaeokarst forms are not so common.
The karst forms and their sediment fillings were encountered in the Dębnik Anticline (Kraków region, Southern Poland) composed of Middle Devonian to Mississippian carbonates. The development of karst slightly postdates the Permian (ca. 300 Ma) volcanic activity in the Kraków region. In this region major transcontinental strike and slip Hamburg-Kraków-Dobruja fault zone induced a series of minor, en echelon, extensional faults, which served as magma passages and guided karst conduits.
The karst forms in the Dębnik Anticline reach several to tens of meters in size. They are filled with: i) massive, subaqueous, coarse crystalline calcite spar; ii) crystalloclastic, bedded limestones; iii) jasper lenses; iv) kaolinitised tuffs. The sediments are characterized by red colouration caused by iron compounds.
Coarse crystalline calcite spar composes beds up to several dozen centimeters in thickness. They are laminated and comprise frutexites type structures. The calcites are interbedded with pinkish-red crystalloclastic limestones, which are built of detritic calcite crystals from silt size to a few millimeters across. Some of the crystals are of skeletal type. Crystalloclastic limestones are normally graded. Both calcite spar and crystalloclastic limestones underwent synsedimentary deformations, which resulted in brecciation and plastic deformations.
The above deposits fill karst forms up to a few metres in lateral extent. However, analogously filled enormously huge (up to around 100 m across) forms were recognized in the early 80s of the last century. Presently, they are completely exploited.
The karst forms were fragments of extensive circulation system. It was fed by waters of elevated temperature, rich in endogenic CO2, which is proved by fluid inclusion analysis and stable isotope investigation. The origin of this system was associated with volcanic activity. The roots of the system are represented by fissures filled with coarse crystalline, red and white calcites of onyx type, which are common in the Dębnik Anticline. Water issuing from this system on the surface caused precipitation of red travertines. These travertines are preserved only as clasts in the Lower Permian conglomerates deposited in the local tectonic depressions.
The study was financed by Ministry of Science and Higher Education project N307 022 31/1746.


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