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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-in lake is a shallow body of water whose basin is produced by collapse of the ground following thawing of ground ice in regions underlain by permafrost. synonym: thermokarst lake.?

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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 16 to 30 of 50
Karst et mines en France et en Europe : gtes, grottes-mines et gotechnique, 1996, Nicod, J.
Many ores have been extracted in the karst areas since the proto-historic times. The ores have been trapped in the paleokarsts, according to various processes whose origin is still much debated. Certain metal-rich minerals have been excavated in caves or "mine-caves". Many polymetallic ores in paleokarstic deposits were in exploitation in SW Sardinia, Sierra of Carthagena, Montagne Noire, Peak District, and Upper Silesia... The mercury mines of Idrija (Slovenia) and the uranium deposits of Tyuya Muyun (Kirgizia) are of particular interest. Recent studies have clearly shown the historic importance of numerous pockets of pisolitic iron (Siderolithic, Bohnerz) in the European steel metallurgy, since the Celts and Romans and up to the middle of the 19th century. The siderite ores raise special problems. Most bauxite deposits were found in karstic pockets and paleo-poljes (mediterranean type of bauxites). The studies of the old mines give a better insight into paleokarsts. Both the ancient and modern mines have created artificial karsts, and raise many geotechnical and environmental problems.

Lithobius nuragicus n.sp., a new Lithobius from a Sardinian cave (Chilopoda, Lithobiomorpha)., 1996, Zapparoli Marzio
A new species of Lithobius from a Sardinian cave (Cagliari, Santadi, loc. Su Benatzu, Grotta "Pirosu", 576 Sa/Ca, m 270) is described. Lithobius nuragicus n. sp. belongs to the subgenus Lithobius s. str. and is related to Lithobius variegatus Leach, 1814, occurring in the British Isles, Brittany, Channel Isles, Iberian Peninsula, Maghreb, Sicily and Southern Italy. This new species is differentiated from L. variegatus by the number of prosternal teeth (3+3), the number and arrangement of ocelli (1+3; little, depigmented, not contiguous to each other, in the center of a depigmented area, posterosuperior ocellus larger than the other ocelli), the size of the organ of Tmsvry (larger), the number of antennal articles (79-86), the number of dorso-lateral and dorso-median setae and the shape and size of the claw of the female gonopods (4-5; 10-11; short, with a small lateral denticle on the internal side).

Genetic divergence and evolutionary times: calibrating a protein clock for South-European Stenasellus species (Crustacea, Isopoda), 1997, Argano Roberto, Sbordoni Marina Cobolli, Matthaeis Elvira De, Ketmaier Valerio
We studied genetic divergence in a group of exclusively stygobiont isopods of the family Stenasellidae. In particular, we assessed evolutionary relationships among several populations of Stenasellus racovitzai and Stenasellus virei. To place this study in a phylogenetic context. we used another species of Stenasellus, S. assorgiai, as an outgroup. S. racovitzai occurs in Corsica, Sardinia and in the fossil islands of the Tuscan Archipelago, while S. virei is a polytypic species widely distributed in the central France and Pyrenean area. This vicariant distribution is believed to be the result of the disjunction of the Sardinia-Corsica microplate from the Pyrenean region and its subsequent rotation. Since geological data provide time estimates for these events, we can use the genetic distance data to calibrate a molecular clock for this group of stygobiont isopods. The calibration of the molecular clock reveals a roughly linear relationship (r = 0.753) between the genetic distances and absolute divergence times, with a mean divergence rate (19.269 Myr/DNei,) different from those previously reported in the literature and provides an opportunity to shed some light on the evolutionary scenarios of other Stenasellus species.

Argillite debris converted to bauxite during karst weathering: evidence from immobile element geochemistry at the Olmedo Deposit, Sardinia, 1997, Maclean W. H. , Bonavia F. F. , Sanna G. ,

Permo-Mesozoic multiple fluid flow and ore deposits in Sardinia: a comparison with post-Variscan mineralization of Western Europe, 2002, Boni M, Muchez P, Schneider J,
The post-Variscan hydrothermal activity and mineralization in Sardinia (Italy) is reviewed in the framework of the geological and metallogenic evolution of Western Europe. The deposits can be grouped into (a) skarn, (b) high- to low-temperature veins and (c) low-temperature palaeokarst. The structural, stratigraphical and geochemical data are discussed. The results suggest three hydrologically, spatially, and possibly temporally, distinct fluid systems. System 1 (precipitating skarn and high-temperature veins) is characterized by magmatic and/or (?) magmatically heated, meteoric fluids of low-salinity. The source of metals was in the Variscan magmatites, or in the Palaeozoic/Precambrian basement. System 2 (low-temperature veins and palaeokarst) is represented by highly saline, Ca-rich (formation or modified meteoric) fluids. Sources of the metals were the pre-Variscan ores and carbonate rocks. System 3 is characterized by low-temperature, low-salinity fluids of meteoric origin. The hydrothermal deposits related to Systems 1 and 2 can be framed in a crustal-scale hydrothermal palaeofield', characterizing most of the post-orogenic mineralization in Variscan regions of Western and Southern Europe, allowing for local age differences of each single ore district and background effects. The suggested timing for the hydrothermal events in Sardinia is: (1) Mid-Permian (270 Ma), (2) Triassic-Jurassic. It is suggested that the Mesozoic events were related to the onset of Tethys spreading

The 'Calamine' of Southwest Sardinia: Geology, Mineralogy, and Stable Isotope Geochemistry of Supergene Zn Mineralization, 2003, Boni M, Gilg Ha, Aversa G, Balassone G,
The mining district of southwest Sardinia, Italy, is one of the classic areas where primary carbonate-hosted Zn-Pb sulfide ores are associated with a relatively thick secondary oxidation zone containing Zn (hydroxy-)carbonates and silicates, the so-called 'calamine,' exploited until the 1970s. The extent of the capping oxidized ore zones, reaching deep below the surface, is generally independent of the present-day water table. The base of the oxidation profile containing nonsulfide Zn minerals in various uplifted blocks in the Iglesiente area can be both elevated above or submerged below the recent water table. The genesis of the ores is therefore considered to be related to fossil, locally reactivated, oxidation phenomena. The mineralogy of the nonsulfide mineralization is generally complex and consists of smithsonite, hydrozincite, and hemimorphite as the main economic minerals, accompanied by iron and manganese oxy-hydroxides and residual clays. This study places the secondary ores in the context of the tectonostratigraphic and climatic evolution of Sardinia and includes a petrographic and mineralogic study of the most abundant minerals, relating the mineralogy of secondary Zn and Pb carbonates to their stable C and O isotope geochemistry and constraining the origin of the oxidizing fluids and the temperature of mineralization. The{delta} 18OVSMOW values of smithsonite are homogeneous, regardless of crystal morphology, position, and mine location (avg. 27.4 {} 0.9{per thousand}). This homogeneity points to a relatively uniform isotopic composition of the oxidation fluid and corresponding formation temperatures of 20{degrees} to 35{degrees}C. Considering the karstic environment of smithsonite formation in southwest Sardinia, this high temperature could be due to heat release during sulfide oxidation. The carbon isotope compositions of secondary Zn carbonates display considerable variations of more than 9 per mil ({delta}13CVPDB from -0.6 to -10.4{per thousand}). This large range indicates participation of variable amounts of reduced organic and marine carbonate carbon during sulfide oxidation. The isotopic variation can be related to a variation in crystal morphologies of smithsonite, reflecting different environments of formation with respect to water table oscillations in karstic environments (upper to lower vadose to epiphreatic). The same range in{delta} 13C isotope values is displayed by the calcite associated with Zn carbonates and by recent speleothems. The most reliable time span for the deposition of bulk calamine ore in southwest Sardinia ranges from middle Eocene to Plio-Pleistocene, although further multiple reactivation of the weathering profiles, peaking within the warm interglacial periods of the Quaternary, cannot be excluded

Nonsulfide Zinc Mineralization in Europe: An Overview, 2003, Boni M, Large D,
A number of occurrences and deposits of nonsulfide zinc ores in Europe were the historical basis for the development of the zinc mining and smelting industry. The principal occurrences in Silesia (Poland), Sardinia (Italy), and northern Spain are described. These deposits are products of the supergene oxidation of primary carbonate-hosted sulfide minerals during the complex interplay of tectonic uplift, karst development, changes in the level of the water table, and weathering. The nonsulfide zinc mineral deposits in the Irish Midlands may represent an example of surface oxidation of primary sulfide mineral deposits, redeposition, and preservation under glacial till. The willemite-dominated mineralization at La Calamine, Belgium, may be related to paleoweathering or be of possible hydrothermal origin, similar to other willemite deposits in the world

Geomorphologic evolution of a coastal karst: the Gulf of Orosei (central-east Sardinia, Italy), 2004, De Waele, Jo

In the past ten years cave surveying has allowed better understanding of speleogenesis in the Orosei Gulf (Central-East Sardinia, Italy), one of the most important coastal karst areas of Italy. Surface geomorphologic research has been accompanied by subterranean and submarine landform analysis in order to try and understand the evolution of this coastal karst since its emersion in Upper Eocene. The main factors influencing the geomorphic processes are lithology, tectonics, palaeo-climate and sea level changes. The study of several important cave systems demonstrates a complex geological history with karst processes that started in Early Tertiary and accelerated during Plio-Quaternary.

Mineralogical and Stable Isotope Studies of Kaolin Deposits: Shallow Epithermal Systems of Western Sardinia, Italy, 2005, Simeone R. , Dilles J. H. , Padalino G. , Palomba M. ,
Large kaolin deposits hosted by Miocene silicic pyroclastic rocks in northwestern Sardinia represent hydrothermal alteration formed within 200 m of the Miocene paleosurface. Boiling hydrothermal fluids ascended steeply dipping faults that are enveloped by altered rock. The broadly stratiform kaolin deposits constitute advanced argillic alteration that was produced in a steam-heated zone near the paleosurface overlying the deeper hydrothermal systems. The deeper zones represent two distinct types of epithermal systems: weakly acidic (inferred low-sulfidation) systems at Tresnuraghes and acidic (high-sulfidation) systems at Romana. Tresnuraghes is characterized at depth by chalcedony {} quartz {} barite veins within a 50-m-wide zone of K-feldspar-quartz-illite alteration and overlying local occurrences of chalcedony sinter, which define the paleosurface. Kaolin deposits near the paleosurface are characterized by zonation outward and downward from an inner shallow zone of kaolinite 1T-opal {} dickite {} alunite (<20-{micro}m-diam grains) to an outer deeper kaolinite 1M-montmorillonite-cristobalite. This zonation indicates formation by descending acidic fluids. The system evolved from ascending weakly acidic or neutral fluids that boiled to produce H2S-rich vapor, which condensed and oxidized within the near-surface vadose zone to form steam-heated acid-sulfate waters and kaolin alteration. At Romana, veins at depth contain chalcedony or quartz and minor pyrite and are enclosed in up to 20-m-wide zones of kaolinite 1T-quartz alteration. Near hydrothermal vents along the paleosurface, chalcedonic silica is enclosed within a zone of kaolinite 1T-alunite (<50-{micro}m-diam grains)-quartz-opal {} dickite {} cristobalite. Kaolin quarries near the paleosurface display outward and downward zoning to kaolinite 1T-opal {} cristobalite and then to montmorillonite-kaolinite 1T {} opal, consistent with formation by descending low pH fluid. The siliceous and advanced argillic alteration along steep conduits formed from acidic ascending magmatic-hydrothermal fluids, whereas the near-surface kaolin formed from steam-heated meteoric waters. Alteration mineral assemblages and stable isotope data provide evidence of the temperature and source of hydrothermal fluids. Barite from Tresnuraghes (average{delta} 18O = 17.1{per thousand},{delta} 34S = 18.8{per thousand}), one alunite sample from Romana ({delta}18O = 12.0{per thousand},{delta} D = -3{per thousand},{delta} 34S = 16.7{per thousand}), and quartz from both localities ({delta}18O = 15.9-22.0{per thousand}) formed in hydrothermal feeders. Source fluids were likely mixtures of meteoric water and minor magmatic fluid, similar to other epithermal systems. Kaolinite-dickite minerals from the kaolin deposits ({delta}18O = 16.6-21.4{per thousand},{delta} D = -43 to -53{per thousand}) formed from steam-heated meteoric water having{delta} D = - 20 per mil, consistent with the presence of anomalous Hg and fine-grained Na- and Fe-poor alunite. The laterally extensive kaolin deposits in Sardinia, and possibly similar deposits elsewhere in the world, appear to represent the uppermost parts of large hydrothermal systems that may be prospects for gold at depth

A new hypogean karst form: the oxidation vent, 2006, De Waele Jo, Forti Paolo

Assessment of cover-collapse sinkholes in SW Sardinia (Italy), 2007, Ardau F, Balia R, Bianco M, De Waele J,
The SW part of Sardinia has been afflicted, in recent years, by several cover-collapse sinkholes mostly occurring in low-density population areas. The study area, that lies in the Iglesiente-Sulcis region, is characterized by the cropping out of the Palaeozoic basement related to the South European Hercynian chain, covered with Tertiary-Quaternary sediments. The main rock types that crop out are Palaeozoic metasandstones, metadolostones, metalimestones, shales and metaconglomerates, and Tertiary-Quaternary fluvial-lacustrine continental sediments. The combined application of several geophysical techniques, integrated with boreholes and geotechnical as well as hydrogeological measurements, proved to be very useful and promising in defining in detail the geological context in which each sinkhole has formed. Moreover, the gravity method, even when used alone, proved to be very effective in detecting the regional geological structures to which sinkholes are related. Eventually, the historical analysis of phenomena, the geological knowledge of the Iglesiente-Sulcis area and the results of properly designed geophysical surveys allows the most probable areas for cover-collapse sinkholes to occur in the future to be determined. In fact, this research pointed out that the depth of the sediment-covered Palaeozoic bedrock is one of the major constraints in delimiting hazardous areas, leading to the construction of a preliminary hazard map. This map shows a belt of high risk, and also suggests the areas in which further geophysical and geotechnical investigations should be carried out to estimate the depth of the bedrock

Coastal karst geomorphosites at risk? A case study: the floods of 6-11 December 2004 in central-east Sardinia, 2007, Cossu A, De Waele J, Di Gregorio F,
Extreme rainfall causing floods and great damage occurred in many areas of central-east Sardinia in the period 6-11 December 2004. A total of approximately 700 mm of rain was measured during this extreme event, with a maximum reaching 510 mm of rainfall in 1 day at the rain gauge of Villagrande (Ogliastra). During and immediately after the event all fluviokarstic canyons were activated for at least 1 week, reaching the highest water levels in at least 50 years and reversing great quantities of sediment-loaded water onto the coast and with important geomorphical modifications. There was public fear that serious damage to the natural resources would occur, such as the famous Cala Luna beach that was almost completely destroyed by the flooding of the Codula Ilune River and by the coinciding sea storm. The river, in fact, eroded the longshore bar (beach) and destroyed the small backshore lagoon. A monitoring study has been initiated in order to analyse the natural evolution of this littoral system and to define the resilience of this interesting geomorphosite. The observations have shown that the flood, albeit impacting negatively in the moments immediately after the disaster, almost completely restored the natural equilibrium of this coastal karst geo-ecosystem within a season

Supramonte is one of the biggest and interesting karst areas of Sardinia (Italy), hosting extensive cave systems explored since the 50s. Early cavers and scientists have carried out some dye tests, but hydrogeological research was hindered by lack of accessible underground rivers. A complex subterranean river system has been discovered in the past decade enabling to organise several new tracer tests. The history of cave explorations, the morphology and hydrology of the systems and the dye tracing experiments are reviewed in this paper in order to give an updated view on hydrogeology of this important karst area.

Interaction between a dam site and karst springs: The case of Supramonte (Central-East Sardinia, Italy), 2008, De Waele Jo, Forti Paolo

Sardinia is one of the Italian regions with the greatest number of dams per inhabitants, almost 60 for a population of only 1.5 million people. Many of these dam sites are located on non-carbonate rocks along the main rivers of the Island and their waters are used for irrigation, industrial, energy supply, drinking and flood regulation purposes.  The Pedra 'e Othoni dam on the Cedrino river (Dorgali, Central-East Sardinia) is located along the threshold of the Palaeozoic basement on the Northern border of the Supramonte karst area, where water is forced to flow out of the system through several resurgences, the most famous of which is the Su Gologone vauclusian spring, used for drinking water supply. The other main outflows of the system, Su Tippari and San Pantaleo springs, are at present almost permanently submerged by the high water level of the Pedra 'e Othoni dam. In the near future water will be supplied also to other communities with a possible increase of water taken from the spring.

The dam, originally meant to regulate the flooding of Cedrino river but actually used for all sorts of purposes (electricity supply, drinking water, irrigation of farmlands, industrial uses), has a maximum regulation altitude of 103 m a.s.l., only slightly less than a meter below the Su Gologone spring level (103.7 m), and 4 and 9 m respectively above the submerged Su Tippari and San Pantaleo springs.

During floods of the Cedrino river, occurring on average twice a year, also the Su Gologone spring becomes submerged by the muddy waters of the lake for a time ranging between a couple of hours up to several days, making water supply impossible. 

The analysis of the available meteorological and hydrogeological data relative to the December 2004 flood, one of the severest of the past 100 years, suggests that the reservoir is filled in a few days time. Several flooding scenarios have been reconstructed using digital terrain models, showing that backflooding submerges most of the discharge area of the aquifer, having important repercussions also on the inland underground drainage system. The upstream flood prone areas prevalently comprise agricultural lands with some sparse houses, but also highly frequented tourist facilities. Fortunately flooding occurs outside the tourist season, thus limiting risk to a limited number of local inhabitants. Massive discharge at the dam site, instead, determines a more hazardous situation in the Cedrino coastal plain, where population density in low lying areas is much higher. To avoid flooding hazard upstream the water level in the lake should be regulated, keeping it low in the flood prone seasons, and having it filled from the end of the winter in order to have enough water stocked before the beginning of the summer. Discharge at the dam site, instead, should be done cautiously, preventing severe flooding of the coastal Cedrino plain.

Monk seal (Monachus monachus) bones in Bel Torrente Cave (central-east Sardinia) and their paleogeographical significance, 2009, Waele J. De, Brook G. A. , And Oertel A.
Fragments of monk seal bones (Monachus monachus) discovered 712 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 50006500 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.

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