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Featured articles from Cave & Karst Science Journals
Characterization of minothems at Libiola (NW Italy): morphological, mineralogical, and geochemical study, Carbone Cristina; Dinelli Enrico; De Waele Jo
Chemistry and Karst, White, William B.
The karst paradigm: changes, trends and perspectives, Klimchouk, Alexander
Long-term erosion rate measurements in gypsum caves of Sorbas (SE Spain) by the Micro-Erosion Meter method, Sanna, Laura; De Waele, Jo; Calaforra, José Maria; Forti, Paolo
The use of damaged speleothems and in situ fault displacement monitoring to characterise active tectonic structures: an example from Zapadni Cave, Czech Republic , Briestensky, Milos; Stemberk, Josef; Rowberry, Matt D.;
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:
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About 50 japygids, belonging to 29 distinct forms of which 23 are recognizable, have been collected since 1874 in caves all over the world. A list is given, by continent and by countries. Ten species found both in the soil and in caves are called troglophiles to emphasize the sorting which seems to occur among endogenous species. Of the remaining 13 species, all considered troglobites, only 3 show morphological peculiarities which can be ascribed to adaptation to cavernicolous life: (1) Metajapyx moroderi ssp. patrizianus Pagés from Sardinia shows a slightly longer l0th urite and cerci than the f. typ.; (2) Kohjapyx lindbergi Pagés from Afghanistan is characterized by its very long l0th urite, its relatively slender cerci, and the presence of more than 8 placoid sensillae (maximum basic number in endogenous species) on the apical segment of the antennae; (3) Austrjapyx leleupi Pagés from the Lower Congo fits most closely the picture of the true troglobite; almost entirely depigmented, slender, with elongate legs, long setae, and the antennae with two of the trichobothria 4 to 5 times as long as the other typical 11, as well as 14 placoid sensillae on the apical segment. It is noted in the conclusion that, among the Diplura and Myriapoda, the almost exclusively phytophagous or saprophagous Campodeids and millipedes include a large number of true troglobites, in contrast with the carnivorous Japygids and centipedes, which have very few troglobites.
Description of three eyeless and apigmented new species of Trichoniscidae which have been found in Su Mannau cave in Sardinia. Two of them belong to the genus Catalauniscus Vandel: Catalauniscus hirundinella n.sp. offering few relationships with the spanish species C. espanoli Vandel, and Catalauniscus puddui n.sp. which has also similar features to an iberian form, C. bolivari Arcangeli. The third (Scotoniscus janas n.sp.) belongs to the endemic genus Scotoniscus Racovitza, until now monospecific and represented by a series of subspecies from the Northern Pyrenees, all nearly related to the specific form S. rnacromelos Racovitza. The discovery of those three new species brings forward additional arguments to the thesis of a Tyrrhenian origin of these taxa of Trichoniscidae.
The study of the biogeography of the eight species of Isopoda Trichoniscidae from Sardegna brings to consider the faunistic relationships happened in the past between the island and the Pyrenees. Two of the species are eutroglophilous and rather widespread; the other six are troglobic and endemic to Sardinia. Five of the latter show strong affinity to Pyrenees forms. A detailed description is given of the distribution of the various species. This distribution makes possible some observations on the history of the fauna of the island.
Description of three eyeless and apigmented new species of Trichoniscidae which have been found in Su Mannau cave in Sardinia. Two of them belong to the genus Catalauniscus Vandel: Catalauniscus hirundinella n.sp. offering few relationships with the spanish species C. espanoli Vandel, and Catalauniscus puddui n.sp. which has also similar features to an iberian form, C. bolivari Arcangeli. The third (Scotoniscus janas n.sp.) belongs to the endemic genus Scotoniscus Racovitza, until now monospecific and represented by a series of subspecies from the Northern Pyrenees, all nearly related to the specific form S. rnacromelos Racovitza. The discovery of those three new species brings forward additional arguments to the thesis of a Tyrrhenian origin of these taxa of Trichoniscidae.
The study of the biogeography of the eight species of Isopoda Trichoniscidae from Sardegna brings to consider the faunistic relationships happened in the past between the island and the Pyrenees. Two of the species are eutroglophilous and rather widespread; the other six are troglobic and endemic to Sardinia. Five of the latter show strong affinity to Pyrenees forms. A detailed description is given of the distribution of the various species. This distribution makes possible some observations on the history of the fauna of the island.
The systematic position, variability and distribution of the two species of Rhachomvces parasitic on Italian Duvalius are defined on the basis of several new findings. Rhachomyces stipitatus Thaxter was found in Liguria, central Italv, Sicilv and Sardinia; its synonyrny with R. capucinus Thaxter is confirmed and the ssp. pallidus Maire is considered of no systematic relevance. R. maublancii, whose position is regularized by a Latin validating diagnosis, was only found on the Alps and previous records in other countries are questioned.
Sr content of 137 samples of barite, 81 samples of fluorite, and 65 samples of calcite from 27 post-Cambrian karst and hydrothermal deposits. Karst calcites have an average Sr content of 26 ppm, quite similar to that of the hydrothermal calcites. Hydrothermal fluorites show an average content of 56 ppm. Forty-five percent of the karst barites have an Sr content over 6,000 ppm, while as much as 83.8 percent of the hydrothermal barites contain more than 6,000 ppm Sr. The Sr isotope composition of the Cambrian stratiform barites (0.70867 or - 3) is similar to that of Cambrian seawater, suggesting that the bulk of the Sr was provided by this source. The Sr isotope ratios of the karst barite (average 87 Sr/ 86 Sr = 0.70947 or - 1) indicate that Sr was not only derived by recycling of the stratiform barite but was also provided by the noncarbonate fraction of the Cambrian wall rocks. The Sr isotope composition of the hydrothermal barites ranges from 0.70990 or - 4 to 0.71837 or - 4, suggesting that the Sr derived mainly from a high 87 Sr/ 86 Sr ratio source.--Modified journal abstract
Several kinds of base metal deposits occur in the lower Paleozoic of southwest Sardinia (Iglesiente-Sulcis mineral district). This paper deals with those deposits which are generally referred to as Permo-Triassic, because they accompany and postdate the Hercynian orogeny and are related to magmatic activity. A large number of previously published geochemical data, integrated with additional new data (Sr, Pb, O, C, and S isotopes), are reviewed and discussed in the frame of the late to post-Hercynian geologic evolution of southwest Sardinia. According to geological and mineralogical characteristics, three types of deposits can be distinguished: (1) skarn ores related to late Hercynian leucogranitic intrusions, (2) high-temperature veins, and (3) low-temperature veins and karst filling. Pervasive epigenetic dolomitization phenomena are geochemically related to the low-temperature deposits. Sr and Pb isotopes of the first and second types (0.7097-0.7140 Sr-87/Sr-86; 17.97-18.29 Pb-206/Pb-204; 38.11-38.45 Pb-208/Pb-204) are distinctly more radiogenic than those of the third type (0.7094-0.7115 Sr-87/Sr-86; 17.86-18.05 Pb-206/Pb-204; 37.95-38.19 Pb-208/Pb-204) which, in turn, are closer to Paleozoic ores and carbonates. Fluid inclusion data indicate that the fluids responsible for mineralization of the first and second types of deposits were hot and dilute (T(h)= 370-degrees-140-degrees-C; <5 wt % NaCl equiv). In contrast, relatively colder and very saline fluids (T(h)= 140-degrees-70-degrees-C; >20 wt % NaCl equiv) were responsible for the third type of mineralization, as well for epigenetic dolomitization of the Cambrian host rocks. O isotopes measured in minerals from the first two types (deltaO-18SMOW = 12.8-18.9 parts per thousand) are O-18 depleted with respect to the third type (deltaO-18SMOW = 15.9-22.1 parts per thousand). These data, coupled with fluid inclusion formation temperatures, indicate that the fluids responsible for the first two types of mineralization were O-18 enriched with respect to those of the third type and related hydrothermal phenomena. The deltaS-34CDT in sulfides of the first two types vary between 3.7 and 10.73 per mil, whereas the values of the third type range from 12.0 to 17.9 per mil. Late to post-Hercynian mineralization is thus explained as the result of three distinct, though partly superimposed, hydrothermal systems. System 1 developed closer to the late Hercynian leucogranitic intrusions and led to the formation of the first and subsequently the second type of mineralization. The relatively hot and diluted fluids had a heated meteoric, or even partly magmatic, origin. Metals were leached from an external, radiogenic source, represented either by Hercynian leucogranites or by Paleozoic metasediments. Sulfur had a partly magmatic signature. System 2 was characterized by very saline, colder fluids which promoted dolomitization, silicification, and vein and karst mineralization. These fluids share the typical characteristics of formation waters, even though their origins remain highly speculative. The hydrothermal system was mainly rock dominated, with only a minor participation of the external radiogenic source of metals. Sulfur was derived by recirculation of pre-Hercynian strata-bound ores. System 3 records the invasion of fresh and cold meteoric waters which precipitated only minor ore and calcite gangue. It may represent the further evolution of system 2, possibly spanning a time well after the Permo-Triassic. The timing of all these phenomena is still questionable, due to the poor geologic record of the Permo-Triassic in southwest Sardinia. Nevertheless, the hypothesized scenario bears many similarities with hydrothermal processes documented throughout the Hercynian in Europe and spanning the same time interval. A comparison with the latter mineralization and hydrothermal activities leads to the hypothesis that the first two types of mineralization are linked to late Hercynian magmatic activity, whereas the third type may be related to either strike-slip or tensional tectonics which, throughout Europe mark the transition from the Hercynian orogeny to the Alpine cycle
Three new species of harpacticoid copepods are described and discussed. Nitocrella beatricis n. sp. has been collected in different hyporheic sites in Sardinia and in two caves (Bue Marino cave in Sardinia and St. Barthélémy cave in Corsica); Elaphoidella janas n. sp. and Parastenocaris triphyda n. sp. have been collected only in Bue Marino cave. Some considerations concerning the ecology and biogeography of the three species are also presented.
During the middle Cretaceous the karst bauxites of NW Sardinia are controlled by a favourable climate, an aluminous mother rock (Berriasian marls) and a significant tectonic instability which allows a morphostructural paleosurface to be constituted on the intracontinental areas, away from the eustatic changes of sea level. In connection with the uplift rate, the aluminous material is distributed into three types of deposit. Their genetic depositional system and main features are incorporated in a geodynamic model applicable to prospecting
After a short history of the discovery of the caves of "Is Zuddas" a geological description of the region and the geomorphological evolution of the cave are recorded. The results of a preliminary climatological research are reported and a rough evaluation of the visitors capacity is also given.
The Oletta cave seems to be one of the largest underground caves in Corsica. The relationship between the organisation of the deforming strata and the karstic network shows that it is a karst of structural origin which has developed above the basic level. The karstification seems old and the speleothemes have to be connected with the phenomena of the climatic break of the Quaternary. Four types of fossiliferous infillings are known. The largest one is the oldest. They express the alternation of phases of sedimentation with different sedimentary dynamics. The most often found fauna is composed of mammals and gasteropoda. At least three faunal groups emerge: an old fauna with Cynotherium sardous, Nesoleipoceros cazioti and Enhydrictis sp. that can be attributed to the Early Wurm or to the limit of the Middle and Upper Pleistocene; a middle fauna to the terminal Wurm and which is characterised here by the absence of the three above mentioned mammals and lastly, a third group where the present fauna appears with, first, it seems, Rattus and Apodemus whereas Prolagus sardus persists for a long time
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