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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 troglobite is 1. an animal living permanently underground in the dark zone of caves and only accidentally leaving it [10]. 2. a creature that is fully adapted to life in total darkness and can only complete its life cycle underground [13]. 3. a creature that lives permanently underground beyond the daylight zone of a cave. many troglobitic species are adapted in some way to living in a totally dark environment. synonyms: (french.) troglobie; (german.) troglobiont; (greek.) troglothitis; (italian.) troglobio; (russian.) troglobiont; (spanish.) troglobio; (turkish.) troglobit, kor balik.?

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 sardinia (Keyword) returned 50 results for the whole karstbase:
Showing 31 to 45 of 50
Evaluating disturbance on mediterranean karst areas: the example of Sardinia (Italy), 2009,
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De Waele Jo, Forti Paolo

Evaluating the human disturbance on karst areas is a difficult task because of the complexity of these peculiar and unique environments. The human impact on karstic geo-ecosystems is increasingly important and there is an increasing need for multidisciplinary tools to assess the environmental changes in karst areas. Many disciplines, such as biology, geomorphology, hydrology and sociale-conomical sciences are to be considered to sufficiently evaluate the impact on these intrinsically vulnerable areas.

This article gives an overview of the evolution of environmental impact on karst areas of the island Sardinia (Italy). For this particular case, the most important impacts in the past 50 years are derived from the following activities, in decreasing importance: (1) mining and quarrying; (2) deforestation, agriculture and grazing; (3) building (widespread urbanisation, isolated homes, etc.) and related infrastructures (roads, sewer systems, aqueducts, waste dumps, etc.); (4) tourism; (5) military activities. To evaluate the present environmental state of these areas the Disturbance Index for Karst environments [Van Beynen and Townsend (Environ Manage 36:101–116)] is applied in a slightly modified version. Instead of considering the indicators of environmental disturbances used in the original method, this slightly modified index evaluates the disturbances causing the deterioration of the environmental attributes. In the Sardinian case study, 27 disturbances have been evaluated, giving rise to the definition of a Disturbance Index ranging between 0 (Pristine) and 1 (highly disturbed). This Disturbance Index simplifies the original KDI method, appears to adequately measure disturbance on Mediterranean karst areas and could be applied with success to other similar regions.


Morphology and origin of coastal karst landforms in Miocene and Quaternary carbonate rocks along the central-western coast of Sardinia (Italy), 2009,
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De Waele Jo, Mucedda Mauro, Montanaro Luca

In the area of Punta Funtanas (Arbus, Central-West Sardinia) somesmall surfaces ofMiocene limestones crop out, partially covered with Quaternary calcarenites and Plio-Quaternary basalts. The biggest of these outcrops forms a fossilwave-cut shore platformof up to 50m wide with an altitude above sea level of approximately 4–5m. On this platformawide variety of dissolution landforms can be observed. Thesemorphologies are related to the influence of the seawater (zone of wave action, marine splash and spray zone, up to progressively more continental environments) and to biokarst processes (erosional action ofmarine organisms, algae andmicro-organisms) and are arranged in bands parallel to the coast, corresponding to different morphological zones.

This paper describes all the karst landforms observed in this coastal area from a morphological and genetic point of view.


Monk seal (Monachus monachus) bones in Bel Torrente Cave (central-east Sardinia) and their paleogeographical significance, 2009,
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Brook George, De Waele Jo, Oertel Anke

Fragments of monk seal bones (Monachus monachus) discovered 7–12 m below water level in Bel Torrente Cave (central-east Sardinia) in 2004 have been AMS radiocarbon dated. The bones, probably of different individuals, have calibrated ages ranging from 5000–6500 calendar years B.P. and allow reconstruction of the paleogeography of the cave and the surrounding area during this time period. Monk seals living in large numbers along the Sardinian coast used the cave for shelter and to give birth to their pups. The lower sea level of the mid-Holocene, combined with cave morphology, allowed them to reach far into the main tunnel of the cave. The large number of bones found of approximately the same age seems to indicate that the monk seals used caves either to shelter from storm waves or to escape from natural predators during periods when human disturbance of the coast was minor. This could suggest the monk seals had other predators they were also trying to avoid.


Speleothems and speleogenesis of the hypogenic Santa Barbara Cave System (South-West Sardinia, Italy), 2010,
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Pagliara Antonio, De Waele Jo, Forti Paolo, Galli Ermanno, Rossi Antonio

This paper presents the results of a study on the peleogenesis and the speleothems and secondary mineralisations of the Santa Barbara Cave System in the Iglesiente Mining District (South-West Sardinia, Cagliari). This cave system, hosted in Cambrian carbonate rocks, has a very long geological history and its main voids have formed in hypogenic conditions. Nine speleogenetic phases can be recognised ranging in age between Cambrian and Holocene. Optical microscope and diffractometric analysis of active flowstone deposits have shown them being composed of alternating calcite and aragonite layers. The textural and chemical characteristics of these layers, obtained by SEM and EDAX analysis, suggest them to be related to variations in the depositional environment inside the cave, which in turn are probably correlated to external climatic oscillations.


On the formation of dissolution pipes in Quaternary coastal calcareous arenites in Mediterranean settings, 2010,
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De Waele Jo, Lauritzen Steinerik, Parise Mario

A large number of uniform cone-shaped dissolution pipes has been observed and studied in Quaternary coastal calcareous arenites in Apulia and Sardinia (Italy) and Tunisia. These cylindrical tubes have a mean diameter of 52·8 cm and are up to 970 cm deep (mean depth for sediment-free pipes is 1·38 m). They generally have smooth walls along their length, are perfectly vertical and taper out towards their bottoms. Their development is not influenced by bedding nor fractures. Sometimes their walls are coated by a calcrete crust. Their morphology has been studied in detail and their relationships with the surrounding rocks and with the environment have been analysed. The perfectly vertical development is a clear evidence of their genesis controlled by gravity. The depth of the dissolution pipes can be described by an exponential distribution law (the Milanovic distribution), strongly suggesting they developed by a diffusion mechanism from the surface vertically downward. We believe dissolution pipes preferentially form in a covered karst setting. Local patches of soil and vegetation cause infiltration water to be enriched in carbon dioxide enhancing dissolution of carbonate cement and local small-scale subsidence. This process causes the formation of a depression cone that guides infiltrating waters towards these spots giving rise to the downward growth of gravity-controlled dissolution pipes. A change of climate from wetter phases to drier and hotter ones causes the formation of a calcrete lining, fossilizing the pipes. When the pipes become exposed to surface agents by erosion of the sediment cover or are laterally breached the loose quartz sand filling them may be transported elsewhere. 


Tafoni and Alveole Formation. An Example from Naxos and Tinos Islands, 2010,
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Evelpidou Niki, Leonidopoulou Dimitra, Vassilopoulos Andreas

Weathering formations resembling small caves, known by the name of Tafoni, are a characteristic, but not exclusive, feature of the Mediterranean area. Examples of such geomorphological formations have been recorded in Sardinia and Corsica (Klaer, 1956; Frenzel, 1965), in Tuscany (Martini, 1978), in S. Spain (Mellor et al., 1997) and in the Aegean Sea area (Greece) (Riedl, 1991; Hejl, 2005).


Flash flood hydrology in karstic terrain: Flumineddu Canyon, central-east Sardinia, 2010,
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De Waele Jo, Martina Mario L. V. , Sanna Laura, Cabras Salvatore, Cossu Quirico Antonio

In the last five winters (2004–2008) several exceptional meteorological events producing flash floods have been registered in central-east Sardinia. The first of these (December 2004) was the most severe and caused important geomorphic changes in the Riu Flumineddu watershed where the influence of human activity is limited. The hydrological characterisation of this flood is extremely difficult because of the lack of streamflow gauges and the relative paucity of meteorological stations in the region. Peak discharge of the fluviokarstic Riu Flumineddu Canyon has been estimated based on a distributed hydrological model (TOPKAPI) and on empirical methods based on geomorphic and sedimentological observations. The comparison between the results derived from these independent methods allows us to obtain the best possible estimate of peak discharge. Differences between modelled and measured peak flows can be attributed to water losses and/or gains along the river channel from interactions with the underground karst drainage network.

The December 2004 flood, with an estimated recurrence interval of at least 65 years, generated overbank flow and destroyed several bridges in upstream reaches, caused important changes in channel morphology and sediment distribution and was able to move boulders up to 1 m in diameter in downstream reaches.


Laser Scanning Technology for the Hypogean Survey: the case of Santa Barbara Karst System (Sardinia, Italy), 2011,
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Canevese Erminio Paolo, Forti Paolo , Naseddu Angelo, Ottelli Luciano, Tedeschi Roberta

The morphological knowledge of the territory, both in its surface and subterranean aspects, is the main premise to all decision-making procedures as well as all planning and management activities. Knowledge takes shape into reliable precise and complete thematic cartography and databases, which are necessary for anybody dealing with underground contexts: speleologists, scientists, public administrations, managing authorities etc.
Surveys in caves are normally carried out with traditional techniques and instruments, which are essential for a first representation but not enough for a pragmatic effective topographic approach. Laser scanning technique can be an alternative to the traditional systems. Laser scanning quickly acquires the shape of cavities as “point clouds” (x, y, z coordinates and colour values) and produces a high precision database of the surveyed object. Laser scanning technology is therefore a feasible way to document caves in a precise exhaustive way, limiting risks relating to lack and/or inadequacy of data.
The present paper explains the laser scanning survey carried out in San Giovanni mine near Iglesias (Sardinia, Italy), particularly in Santa Barbara and Santa Barbara 2 caves, the data post-processing and three-dimensional modelling of “point clouds” (operations performed with a dedicated software), and
the use of the obtained digital model. Moreover, the paper describes
the advantages of laser scanning for the hypogean survey
in comparison to traditional methods and the future potentialities
of a broad application of laser scanning instruments
in caves.


Trace element and stable isotope data from a flowstone in a natural cave of the mining district of SW Sardinia (Italy): evidence for Zn⁺-induced aragonite precipitation in comparatively wet climatic conditions, 2011,
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Caddeo Guglielmo Angelo, De Waele Jo, Frau Franco, Railsback Loren Bruce

A speleothem from Crovassa Azzurra, a mine cave in SW Sardinia (Italy), has been analysed for mineralogy, minor and trace elements and stable isotopes. It is composed of layers of primary calcite and aragonite, with a region of secondary calcite. The primary carbonate is strikingly rich in Zn and Pb, presumably as the result of transport in solution from overlying Pb-Zn deposits. Immediately below the transition between calcite and aragonite, concentrations of Zn, Cd and P increase. At the transition between aragonite and Pb-rich aragonite, concentrations of Pb and P increase. Stable isotopes indicate an evolution toward more humid periods for these two transitions, conversely to what is normally observed in calcite-aragonite speleothems. The combined observation of increase in P and metals derived from oxidation of sulphides and the variation of isotopic composition of aragonite and calcite suggests that in this mine cave aragonite was deposited with increasing flowrate and thus more humid conditions. In addition, the effect of Zn2+ or Pb2+ in inhibiting precipitation of calcite appears to have been more important than that of Mg2+.


The Seulo Caves Project, Sardinia: a report on archaeological work undertaken in 2009 and 2010, 2011,
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Skeates, R.

This report introduces a new archaeological research project investigating the human uses of caves in the territory of Seulo, central Sardinia, and presents the preliminary results of archaeological field-survey, cave-survey, and excavation work undertaken in 2009 and 2010. At least nine caves were occupied in this area during prehistory, between the Middle Neolithic and the Bronze Age (c.4700-850 cal BC). All appear to have been used for the performance of rituals, and can be compared to the ritual use of caves identified elsewhere in the Central Mediterranean region. Nevertheless, significant differences can also be identified at each cave, adding detail and diversity to our understanding of the human uses of caves.


Landscape evolution in the Tacchi area (Central-East Sardinia, Italy) based on karst and fluvial morphology and age of cave sediments, 2012,
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De Waele, J. , Ferrarese F. , Granger, D. Sauro, F.

 

The east-central part of Sardinia (Italy) is characterised by Jurassic
dolomitic mesas (Tacchi, or «table mountains») that overlie a Palaeozoic
basement mainly composed of metavolcanics and phyllites. These mountains
are the remnants of a continuous carbonate cover, dissected by
faults and river erosion, and are now completely isolated hydrological
systems. Most of these rivers have cut valleys more than 200 metres deep
into the Palaeozoic basement rocks, whose slopes are often characterised
by landslides, suggesting their recent oversteepening. Some valleys, on
the contrary, have not reached the base of the carbonate sequence and
appear to be suspended above the deeper incisions, apparently disconnected
by them. Several subhorizontal surfaces can be distinguished on
the table mountains, related to local base level stillstands. Also water
table caves, scattered along the flanks of the mountains over an altitudinal
range of about 200 m, show several stillstands in base level lowering.
 
26Al and 10Be burial dating of sediments in four caves located at different
elevations on the flanks of the suspended Taquisara Valley show
an Upper Pliocene or Lower Pleistocene age. Thus, this valley appears to
be of Late Tertiary age. The deeper valleys, such as Riu Pardu, that dissect
the Tacchi mountains completely, cutting deeply into the basement
rocks, are much younger, as their unstable slopes suggest. Knickpoint retreat
in Riu Pardu and estimated valley erosion rates suggest the capture
of Riu Pardu by Rio Pelau to have occurred in the last 100 ky.

Speleogenesis of an exhumed hydrothermal sulphuric acid karst in Cambrian carbonates (Mount San Giovanni, Sardinia), 2013,
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Dewaele Jo, Forti Paolo, Naseddu Angelo

In the past few years the systematic study of caves intercepted by mine workings in southwest Sardinia has permitted us to observe morphologies due to rare speleogenetic and minerogenetic processes related to ancient hydrothermal activity. These relic morphologies are slowly being overprinted by recent speleogenetic processes that tend to obscure the hypogene origin of these caves. A combined geomorphological and mineralogical investigation has permitted a fairly detailed reconstruction of the various phases of evolution of these caves. Cave formation had already started in Cambrian times, but culminated in the Carboniferous, when most of the large voids still accessible today were formed. A key role in carbonate dissolution was played by sulphuric acid formed by the oxidation of the polymetallic ores present in the rocks since the Cambrian. During the Quaternary a variety of minerals formed inside the caves: calcite and aragonite, that yielded sequences of palaeo-environmental interest, and also barite, phosgenite, hydrozincite, hemimorphite and many others. These minerals are in part due to a phreatic thermal hypogenic cave forming phase, and in part to later epigene overprinting in an oxidizing environment rich in polymetallic ores. Massive gypsum deposits, elsewhere typical of this kind of caves, are entirely absent due to dissolution during both the phreatic cave formation and the later epigenic stage


PLEISTOCENE SEA LEVEL CHANGES AS REVEALED BY FLANK MARGIN CAVES IN TELOGENETIC LIMESTONES IN SICILY AND SARDINIA (ITALY), 2013,
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Dangeli I. M. , Waele J. D. , Ruggieri R. , Sanna L.

Coastal karst areas often host many indices of past sea level changes, such as marine terraces, fossiliferous sediments, tidal notches and coastal caves. Tectonic movements can then displace these ancient coastlines vertically. The interplay between rising or falling sea level and uplifting or subsidence can be very complex and difficult to unravel. The combination of a detailed knowledge of marine terraces and the study of some flank margin caves located at various altitudes have allowed to reconstruct the speleogenetic history of the coastal plain of Cornino-Custonaci (NW Sicily). Along the centraleastern coast of Sardinia, instead, the detailed study of the Fico Cave has allowed to recognise it as a flank margin cave developed on five levels, related to Pleistocene sea level highstands. These studies show that this type of mixing corrosion caves is much more widespread than previously thought also in telogenetic limestones. These caves, being excellent sea level markers, might help coastal geomorphologists to understand more on both sea level rise and fall and tectonic movements in coastal areas.


Speleogenesis of an exhumed hydrothermal sulphuric acid karst in Cambrian carbonates (Mount San Giovanni, Sardinia), 2013,
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De Waele Jo, Forti P. , Naseddu A.

n the past few years the systematic study of caves intercepted by mine workings in southwest Sardinia has permitted us to observe morphologies due to rare speleogenetic and minerogenetic processes related to ancient hydrothermal activity. These relic morphologies are slowly being overprinted by recent speleogenetic processes that tend to obscure the hypogene origin of these caves. A combined geomorphological and mineralogical investigation has permitted a fairly detailed reconstruction of the various phases of evolution of these caves. Cave formation had already started in Cambrian times, but culminated in the Carboniferous, when most of the large voids still accessible today were formed. A key role in carbonate dissolution was played by sulphuric acid formed by the oxidation of the polymetallic ores present in the rocks since the Cambrian. During the Quaternary a variety of minerals formed inside the caves: calcite and aragonite, that yielded sequences of palaeo-environmental interest, and also barite, phosgenite, hydrozincite, hemimorphite and many others. These minerals are in part due to a phreatic thermal hypogenic cave forming phase, and in part to later epigene overprinting in an oxidizing environment rich in polymetallic ores. Massive gypsum deposits, elsewhere typical of this kind of caves, are entirely absent due to dissolution during both the phreatic cave formation and the later epigenic stage.


THE SAN PAOLO MINE TUNNEL AT SA DUCHESSA (DOMUSNOVAS, SW SARDINIA): TEN INTERCEPTED NATURAL CAVES AND FIRST DATA ON THE COMPOSITION OF SOME SPELEOTHEMS , 2013,
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Simone Argiolas, Caddeo Guglielmo Angelo, Casu Lucilla, Muntoni Alberto, Papinuto Silvestro

Since many years cavers from different caving teams are carrying out a systematic study on the caves of Sulcis-Iglesiente, including geomorphological studies. Over thirty natural caves have been explored, surveyed and registered in the past few years, and over half of these have been made accessible by mine galleries. Among these are worth to be mentioned the “Tre Sorelle” of Domusnovas: these are three mine caves intercepted by the San Paolo mine tunnel. This tunnel, whose collapsed entrance has been reopened after a long digging campaign, has been explored and surveyed for around 700 meters. A total of 10 natural caves, mostly developed along fractures, have been explored and mapped, with developments ranging between 10 and 250 meters and depths from 15 to over 160 meters. Only two of these caves were previously known in the Regional Cave Register. In most of the caves, speleothems consist mainly of flowstones, some of which are clear or usually white, others are dark-brown or tending to black. Some samples of the first and the second flowstone types were collected respectively from the “Sesta Sorella” and “Seconda Sorella” Caves. The powders of these samples were analysed by an X-ray diffractometer. The first type consists of thicker layers of white and fibrous aragonite, which sometimes alternate with thinner layers of grey columnar calcite. In some samples, however, calcite interlayers were absent and just aragonite was found. The second type is composed of alternating layers of darkbrown hemimorphite. Some additional analyses were performed on these samples by Laser Ablation ICP-MS to determine the concentration of minor and trace elements in the different layers and mineralogical phases. The most abundant minor elements in calcite layers are Mg and Zn. Magnesium is about constant (~ 2000 ppm) on different spots and remains under the average Mg content of the cave calcite in this region, whereas Zn ranges from 103 to 104 ppm and is well above the Zn average in calcite of caves in the world. Barium concentration is about 80 ppm and more abundant than Pb (20 ppm) and Sr (10 ppm). Barium is also the main minor element in aragonite, where it can reach almost 2000 ppm. The Zn concentration is very high even in aragonite and is comparable to that of Sr (400-500 ppm), overcoming considerably the Pb concentration (20 ppm). In hemimorphite, the most abundant minor elements are Al and Fe (about 104 ppm). However, it was not quantified how much of these are in the hemimorphite lattice or come from some impurities. Actually, we notice that concentration of Fe and Al in the black layers of hemimorphite is an order of magnitude greater than in the brown ones. In addition, the black layers show an abrupt increase of Mn concentration, which overcomes Fe and Al. The evolution of these flowstones is most probably related to the circulation of fluids connected to the oxidation of sulphides, specially sphalerite.


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