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A contribution to petrology of dark grey to black interbeds within Upper Permian and Triassic carbonate rocks in the area between Ljubljana and Bloke, Central Slovenia  [PDF]
Stevo Dozet,Tja?a Kandu?,Milo? Marki?
Geologija , 2012,
Abstract: This paper presents results of macroscopic, microscopic, chemical, and isotopic investigations of 12 samples ofdark grey to black coloured interbeds occurring within Upper Permian and Triassic lime-, dolo- and marlstones inan area of Outer Dinarides between Ljubljana and Bloke in Central Slovenia. An additional sample is anthracite ofthe Carnian age from the Orle locality. Concentration of Corg in four samples is below 1 %, and in seven samples itvaries between 1 and 2.3 %. Only in one sample, in the black Carnian limestone of the Lesno Brdo area, it is somewhathigher than 5 %. The highest Corg content, 30.61 %, was analysed in the Orle anthracite.Chemical analysis of major elements (as oxides) showed that four samples are clearly siliciclastic mudrocks,with 65–80 % SiO2 + Al2O3. Three samples are typical calcite rich – dolomite poor rocks, with high loss on ignition(LOI about 40 %) derived from calcite decomposition. Four samples are calcite – dolomite characterized rocks withLOI of 34–43 %. One sample, from the Slugovo quarry, is composed of quartz, dolomite and calcite. The anthracitesample from Orle has inorganic matter composed almost exclusively of SiO2 + Al2O3 (clays), and some iron and sulphurwhich form pyrite.Isotopic composition of the calcite carbon ranges from δ13CCaCO3 -5.7 to 1.9 ‰, whereas isotopic composition ofthe organic carbon varies between δ13Corg -34.7 and -21.6 ‰. The most negative δ13Corg value of -34.7 ‰ was analysedin a sample, which is the most organic-rich limestone. Isotopic investigations of nitrogen, expressed by δ15N values,also did not express notable differences in respect to lithology. They vary between 4.6 and 9.1 ‰.Microscopy of polished surface samples showed clearly fine grained siliciclastic, carbonate and coal compositionof the treated rocks.
Stratigraphy of Upper Permian and Lower Triassic Strata of the iri Area (Slovenia)
Tea Kolar-Jurkov?ek,Bogdan Jurkov?ek,Dunja Aljinovi?,Galina P. Nestell
Geologija , 2011,
Abstract: The paper deals with the stratigraphy of Late Permian and Early Triassic strata of the Luka section in the iri area of western Slovenia. This is the only section presently known in the External Dinarides where the Permian-Triassic boundary is defined following international criteria based on the first appearance of the conodont Hindeodus parvus. The following lithostratigraphic units have been formalized: the Bellerophon Limestone and Evaporite-dolomite Members of the Bellerophon Formation and the Luka~ Formation with the three members,the Transitional Beds, Streaky Limestone and Carbonate-clastic Member. The paper presents the results of micropaleontologicalstudy based on foraminifers and conodonts as well as petrographic and sedimentologic research results. The investigation of conodont assemblages enabled the conodont biozonation of the Permian-Triassic interval of the studied Luka section.
Ce anomaly at the Permian-Triassic boundary in the Idrijca Valley as evidence of changing redox conditions at the P/Tr transition in the western Tethys (Slovenia)  [PDF]
Tadej Dolenec,Sonja Lojen
Geologija , 2000,
Abstract:
The Permian-Triassic boundary in the Karavanke Mountains (Slovenia): Stable isotope variations in the boundary carbonate rocks of the Ko utnik Creek and Brsnina section
Tadej Dolenec,Stanko Buser,Matej Dolenec
Geologija , 1998,
Abstract:
Hydrogeochemical characteristics of the River Idrijca (Slovenia)  [PDF]
Tja?a Kandu?
Geologija , 2008,
Abstract: The hydrogeochemical and isotope characteristics of the River Idrijca, Slovenia, where the world’s second largest mercury (Hg) mine is located, were investigated. The River Idrijca, a typical steep mountain river has an HCO3- - Ca2+ - Mg2+ chemical composition. Its Ca2+/Mg2+ molar ratio indicates that dolomite weathering prevails in the watershed. The River Idrijca and its tributaries are over saturated with respect to calcite and dolomite. The pCO2 pressure is up to 13 times over atmospheric pressure and represents a source of CO2 to the atmosphere. δ18O values in river water indicate primary control from precipitation and enrichment of the heavy oxygen isotope of infiltrating water recharging the River Idrijca from its slopes.The δ13 CDIC values range from 10.8 to 6.6 ‰ and are controlled by biogeochemical processes in terrestrial environments and in the stream: 1) exchange with atmospheric CO2, 2) degradation of organic matter, 3) dissolution of carbonates, and 4) tributaries. The contributions of these inputs were calculated according to steady state equations and are estimated to be -11 %: 19 %: 31 %: 61 % in the autumn and 0 %: 6 %: 9 %: 35 % in the spring sampling seasons.
Soil-plant mercury concentrations in the Idrijca river terraces (Slovenia)  [PDF]
Mateja Gosar
Geologija , 2004,
Abstract: The subjects of research are mercury contents in plants and soils on river terraces in the lower reaches of the Idrijca River. Samples of averaged meadow forage and plaintain (Plantago lanceolata) contain from 0.055 to 0.220 mg Hg/kg in dry matter. In comparison to samples from Idrija in the 1970's these contents are relatively low with respect to mercury in soil. They are similar to those established in the surroundings of the abandoned Podljubelj mercury mine. However, with respect to contents in non-polluted soils the contents on Idrijca river terraces are considerably above the background.Total mercury in plants is influenced only to some degree by its contents in soils. Comparison of samples on terraces at the Temnikar farm shows that the contents in soil increase discontinuously from the third towards the first terrace. But in plants these differences are small, probably owing to the large part of mercury being contained in cinnabar that is inaccessible to plants. On the first river terrace (TEM3 locality) where soil contains about 55 times more Hg than on the second terrace, the average forage sample contains only 1.6 times and plantain sample 1.8 times higher Hg than the corresponding samples on the third terrace.
Microfacies of Mesozoic Carbonate Rocks of Slovenia  [PDF]
Bojan Ogorelec
Geologija , 2011,
Abstract: Carbonate rocks of Mesozoic age are widespread in Slovenia where they consitute about 40 % of its territory, and attaining total thickness of more than 5000 metres. With respect to microfacies almost all structure types can be recognized, the limestones and dolomites being formed in various sedimentary environments, such as in openand in restricted parts of carbonate shelf, in lagoons and on coastal plains, in different types of reefs, on slopes and in the basin. Carbonate sedimentation was often accompanied also by the supply of terrigenous material and products of volcanic activity. Among diagenetic processes in investigated carbonate rocks the most extensive are dolomitization and silicification.In the present text 250 microscopic photographs of characteristic limestones and dolomites from Slovenian territory are assembled. In the introductory part, to which for orientation schematic stratigraphic columns are added,the geologic development od these carbonate rocks is briefly outlined. For the sake of completeness in presenting the carbonate era in the overview, Upper Permian limestones and dolomites are also described next to Mesozoic beds.
Late Permian magnetostratigraphy and its global correlation
Yugan Jin,Qinghua Shang,Changqun Cao
Chinese Science Bulletin , 2000, DOI: 10.1007/BF02886173
Abstract: A calibration among magnetic polarity sequence, biostratigraphy zonation and isotopic age reveals that the boundary between the Carboniferous-Permian reversed Polarity Superzone and Permian-Triassic Mixed Polarity Superzone occurs at the top of the Wordian Stage of the Guadalupian Series and is dated as 265 Ma. The Late Permian magnetic polarity sequence integrates four polarity zones, corresponding to the Upper Guadalupian Series, the Wuchiapingian Stage, and the Lower and the Upper Changhsingian Stage of the Lopingian Series. This reference magnetostratigraphy polarity sequence may serve as a useful guide to the chronostratigraphic correlation of Late Permian strata across major biogeographic and facies barriers.
Late Permian magnetostratigraphy and its global correlation
JIN Yugan,SHANG Qinghua,CAO Changqun,
科学通报

科学通报(英文版) , 2000,
Abstract: A calibration among magnetic polarity sequence, biostratigraphy zonation and isotopic age reveals that the boundary between the Carboniferous-Permian reversed Polarity Superzone and Permian-Triassic Mixed Polarity Superzone occurs at the top of the Wordian Stage of the Guadalupian Series and is dated as 265 Ma. The Late Permian magnetic polarity sequence integrates four polarity zones, corresponding to the Upper Guadalupian Series, the Wuchiapingian Stage, and the Lower and the Upper Changhsingian Stage of the Lopingian Series. This reference magnetostratigraphy polarity sequence may serve as a useful guide to the chronostratigraphic correlation of Late Permian strata across major biogeographic and facies barriers.
The problems of Paleozoic beds and reconstruction of the Middle Permian sedimentary basin in western Slovenia  [PDF]
Ivan Mlakar
Geologija , 2003,
Abstract: In the first part of paper geologic data from smaller outcrops of Val Gardena Formation in west Slovenia are assembled. Together with the already published information from larger outcrops they permit the reconstruction of the Middle Permian sedimentary basin on which the accent of paper is based. Attention is drawn to general problems of Upper Paleozoic beds, and conclusions regarding lithologic, stratigraphic and structural control of uranium and copper deposits in this part of Slovenia are given.
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