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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.
The Permian-Triassic boundary in the Idrijca Valley (Western Slovenia): isotopic fraction between carbonate and organic carbon at P/Tr transition  [PDF]
Tadej Dolenec,Sonja Lojen,Matej Dolenec
Geologija , 1999,
Abstract:
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.
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.
The Upper Cretaceous paleogeographical rudist subprovinces of the tethys in Slovenia  [PDF]
Mario Pleni?ar
Geologija , 2008,
Abstract: To the present knowlege according to DERCOURT et al. (1985) the following Upper Cretaceous rudist subprovinces in Slovenia can be distinguished from the North to the South:1. Carpathian-Balcanic-Pontidian subprovince2. Transitional subprovince and3. Apulian-Tauridian-intraoceanic subprovince.Rudist deposits of the first subprovince occur in northeastern Slovenia in Pohorje. These deposits contain representativesof the genera Vaccinites, Radiolites and Lapeirouseia. Rudist faunas of the transitional subprovince existed in the regions of the Central Slovenia (Inner Dinarids). In this area rudists and other shallow marine organisms were transported into flysch and deep-marine basins within olistoliths (allochtonous fauna) or as individual specimens. The third subprovince comprise carbonate platformes with rudist associations developed in conditions of the warm and shallow seas.
The importance of Hindeodus parvus (Conodonta) for the definition of the Permian-Triassic boundary and evaluation of the proposed sections for a global stratotype section and point (GSSP) for the base of the Triassic
Heinz W. Kozur,Anton Ramov?,Cheng-yuan Wang,Yurij D. Zakharov
Geologija , 1995,
Abstract: The biostratigraphic Permian/Triassic (P/T) boundary is defined by the first appearance of H. parvus. The first appearance of H. parvus within the dine H. latidentatus-H. parvus is a globally recognizable event in the conodont evolution.The first appearance of H. parvus is not facies related and can be observed both in ammonoid-free shallow-water deposits and in ammonoid-bearing pelagic deposits. H. parvus is a common, easily determinable species known so far from the entire Tethys, Japan, western North America, Boreal realm (Greenland)and the Tethyan margin of Gondwana. H. parvus is the first species withworld-wide distribution to appear after the absolute minimum in the faunal diversity indicated by the minimum in The Meishan section (South China) contains a continuous, pelagic sedimentaryrecord across the P/T boundary without stratigraphie gaps. It is nearly unaltered thermally (CAI = 1-1.5). Its fossil content (ammonoids, conodonts, foraminifers,bivalves, brachiopods, sporomorphs etc.) and event succession have been thoroughlystudied. Absolute age and magnetostratigraphy have also been subjected to intensive studies. The section is readily accessible and under protection of the government. This section is best suitable as a global stratotype section and point (GSSP) for the base of the Triassic. No other section in the world is known tobe qualified for defining the P/T boundary in a GSSP. H. parvus made its earliest appearence in the middle part of Boundary Bed 2 (Bed 27) at Meishan. It evolved within Bed 27 from H. latidentatus within a phylomorphogenetic continuum in a continuous and monofacial stratum. The biostratigraphic P/T boundary lies very close to the event boundary (15 cm above the event boundary at the baseof Boundary Bed 1 = Bed 25, and a few centimetres above the minimum in '13C in the lower Boundary Bed 2).
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.
Ostracods (Crustacea) associated with microbialites across the Permian-Triassic boundary in Dajiang (Guizhou Province, South China)  [cached]
Marie-Beatrice FOREL
European Journal of Taxonomy , 2012, DOI: 10.5852/ejt.2012.19
Abstract: 26 samples were processed for a taxonomic study of ostracods from the Upper Permian (Changhsingian) - Lower Triassic (Griesbachian) interval of the Dajiang section, Guizhou Province, South China. 112 species belonging to 27 genera are recognized. Five new species are described: Acratia candyae sp. nov, Bairdia adelineae sp. nov., Bairdia? huberti sp. nov., Bairdia jeromei sp. nov., Orthobairdia jeanlouisi sp. nov. The unexpected survival faunas associated with microbial formations in the aftermath of the end-Permian extinction are documented for the first time. Ostracod biodiversity variations and palaeo-environmental modifications associated with microbial growth through the Permian-Triassic boundary (PTB) are discussed.
Triassic and Jurassic beds in Krim Mountain area (Slovenia)
Milo? Miler,Jernej Pav?i?
Geologija , 2008,
Abstract: The Krim Mountain and its surroundings are characterized by Upper Triassic to Middle Jurassic rocks, which were deposited on the northern margin of the Dinaric Carbonate Platform. Upper Triassic beds are represented by Main dolomite that exhibits supra- to subtidal Lofer facies. The uppermost Triassic is characterized by approximately 40 m thick horizon of dolomitic breccia. Upper Triassic beds pass gradually into Lower Liassic dolomitic breccia, coarse-grained dolomite and micritic limestone. Presence of dolomitic breccias and absence of supra-intertidal sedimentary structures indicate sea-level rise. Middle Liassic beds consist of oolitic-oncolitic and lithiotid limestones deposited in alternating restricted lagoonal and open shallow-water environment. Upper Liassic beds are characterized by oolitic-oncolitic limestones, bituminous dolomitized limestones and dolomitic breccia deposited in high-energy shallow-water environment. Middle Jurassic beds consist of oolitic, oolitic-oncolitic and micritic limestones, formed predominantly in high-energy subtidal environment.
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