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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.
Carnian bauxite horizon on the Kopitov gri near Borovnica (Slovenia) – is there a forgotten stratigraphic gap in its footwall?
Bogomir Celarc
Geologija , 2008,
Abstract: Beds underlying the Carnian bauxite on the Kopitov gri~ (Slovenia) are by the author’s opinion not Carnian (Cordevolian), but Ladinian age. The considerable stratigraphical gap is presented between Carnian clastic rocks and underlying limestones and dolomites. Bauxite is result of the weathering during the emersion.
Jakov Pranji?,Josip Mesec
Rudarsko-Geolo?ko-Naftni Zbornik , 1992,
Abstract: The paper analyses possibilities of revitalization of ruined areas having specific hydrologic, geologic, climatic and soil factors. A plan for sanation with autochtonous and allochtonous plants is described. Preparatory and planting techniques and general distribution of plants correspond to the conditions and state of the quarry after closure.
Macrofauna of the Carnian beds in the Me ica area
Bogdan Jurkov?ek,Tea Kolar-Jurkov?ek,Glenn S. Jaecks
Geologija , 2002,
Abstract: Three clastic marly-shaly horizons occur within the Carnian carbonate rocks near Me ica and rna na Koro kem, Slovenia. The marly-shaly beds directly overlie oolitic and oncoidal limestones. In the lowermost of these clastic horizons, several cephalophod species,including the most common Carnites floridus (Wulfen), were collected. In addition, bivalves, gastropods and sparse vertebrate remains are present.Within the second clastic horizon, there is a distinctive layer characterized by numerous specimens of the bivalve Hoernesia sturi (W hrmann), which was also found, though less commonly, in the lowermost clastic horizon. No fossil macrofauna was found in the third, uppermost clastic horizon.The oolitic and oncoidal layers at the base of all three clastic horizons also contain abundant echinoids and crinoids, as well as rare earliest thecideide brachiopods.The lithostratigraphic associations of the Carnian beds in the Me ica area express the same eustatically-driven cyclicity that is exhibited regionally in the “Raibl group” of the Eastern Alp
Physicochemical investigation of medieval ceramics from excavation site Novo Brdo
?ugalj Sne?ana S.,Damjanovi? Ljiljana S.,Holclajtner-Antunovi? Ivanka D.,Mio? Ubavka B.
Hemijska Industrija , 2008, DOI: 10.2298/hemind0803143c
Abstract: Artefacts produced or treated at high temperatures provide information about manufacturing techniques. Well preserved ceramic objects are therefore excellent chronological markers as well as general markers of society development. In order to determine provenance of pottery fragments, archaeologists classify samples according to their physical characteristics, decoration and aesthetic style. However, a more objective multidisciplinary approach, based on undoubted results, is necessary to complete this study. In this work we have investigated 27 samples of medieval ceramics from excavation site Novo Brdo, using X-ray fluorescence (XRF), FTIR spectroscopy and X-ray powder diffraction (XRPD). Novo Brdo was large and rich mining and trading center of Serbia in XIV and XV century. A large number of ceramic samples found during the systematic excavation of this archaeological site allow good choice of samples for both destructive and nondestructive analysis. Combining results obtained by different experimental techniques, i.e. by FT-IR spectroscopy, after deconvolution of the spectra, and XRPD analysis, we have determined mineralogical composition and technology of production of investigated pottery. Estimated temperature of firing ranged from 800 to 900 °C, which is in agreement with the presence of high-temperature minerals like gehlenite and anorthite. Firing was preformed in the oxidation atmosphere since hematite, which is formed only in oxidation atmosphere, is detected in all investigated samples. Cross sections showed presence of defects and inhomogeneity of investigated ceramic, which indicates fast and incomplete firing procedure. All these findings indicate that investigated pottery was produced in the domestic workshops. The obtained results will be used to build up the National database for medieval ceramics as well as the database for the Balkan region.
Total exploitation of an ornamental granite quarry
Taboada, J.,Alejano, L. R.,Bastante, F. G.,Ordó?ez, C.
Materiales de Construccion , 2005,
Abstract: In this paper we propose a methodology to estimate the recovery percentage for each of the products which can be obtained from the exploitation of an ornamental granite quarry: block, semiblock, masonry-transverse stone, and the smaller materials that can be used to obtain construction aggregates. This methodology ensures that quarry exploitation is exhaustive, thereby minimising the production of spoils and the consequent negative impact on the environment. The analysis is based on a detailed and exhaustive compilation of discontinuity data from the research fronts, which are then interpreted statistically and projected over the three weakness planes that are a particular feature of ornamental granite deposits. Using this information, and bearing in mind the minimum commercially viable sizes for each kind of granite, the corresponding recovery rates are calculated for each material in each plane. The results are then integrated using spatial techniques, and the result is an evaluation of quarry contents with a view to total exploitation. This methodology was applied to a quarry in the opening phase in order to carry out an a priori assessment of the economic feasibility of the quarry. En este trabajo se propone una metodología para estimar el porcentaje de recuperación de cada uno de los productos que se pueden obtener en la explotación de una cantera de granito ornamental: bloque, semibloque, manpostería y per pia os, y material restante destinado a la obtención de áridos. De esta manera se logra un aprovechamiento integral de la cantera, evitándose la generación de estériles y el subsiguiente impacto ambiental producido por éstos. La metodología de análisis se basa en la recopilación detallada y exhaustiva de datos de discontinuidades en los frentes de investigación, que se interpretan estadísticamente y se proyectan sobre los tres planos de debilidad propios del granito ornamental. Con esta información, y las dimensiones mínimas comerciales de referencia para cada tipo de material, se realiza el cálculo de las recuperaciones correspondientes de cada material en cada plano y los resultados de recuperación sobre estos tres planos se integran mediante técnicas espaciales; obteniéndose la evaluación de los recursos en la cantera para su aprovechamiento integral. La metodología ha sido aplicada a una cantera en fase de apertura para realizar una valoración inicial de su viabililidad económica.
Partial Replacement of Sand with Quarry Dust in Concrete  [PDF]
Mr. Chandana Sukesh,,Mr. Katakam Bala Krishna,,Ms. P. Srilakshmi Sai Teja,,Mr. S. Kanakambara Rao
International Journal of Innovative Technology and Exploring Engineering , 2013,
Abstract: The reduction in the sources of natural sand and the requirement for reduction in the cost of concrete production has resulted in the increased need to identify substitute material to sand as fine aggregates in the production of concretes especially in Concrete. Quarry dust, a by-product from the crushing process during quarrying activities is one of such materials. Granite fines or rock dust is a by-product obtained during crushing of granite rocks and is also called quarry dust. In recent days there were also been many attempts to use Fly Ash, an industrial by product as partial replacement for cement to have higher workability, long term strength and to make the concrete more economically available. This present work is an attempt to use Quarry Dust as partial replacement for Sand in concrete. Attempts have been made to study the properties of concrete and to investigate some properties of Quarry Dust the suitability of those properties to enable them to be used as partial replacement materials for sand in concrete.
Branko Bo?i?,Karlo Braun
Rudarsko-Geolo?ko-Naftni Zbornik , 1992,
Abstract: The optimalization of exploitation in Lakovi i limestone quarry is described. Based on determined discontinuities in the rock mass and their densities, the best possible working site have been located in order to obtain the best possible sizes of blasted rocks and work slope stability. Optimal lowest resistance line size for the quarry has been counted and proved experimentally. New blasting parameters have resulted in considerable saving of drilling and explosive.
Marina Piria,Darija Vrbanec,Gordana ?ur?evi?
Ribarstvo : Croatian Journal of Fisheries , 2011,
Abstract: The rudd is a cyprinid herbivorous freshwater fish. The samples of rudd have been taken from the Klju i brdo“ location. The arithmetic mean of length for each age group was determined according to Peterson, Danish ichthyologist. As back calculation of average length of some populations was done by von Bertalanffy growth function (VBGF) Lt=L∞ (1-e-K(t-t0)), the equation could be expressed by the following formula Lt=17.82 (1-e-1.0431(t-0.579)). The von Bertalanffy growth function is helpful because its parameters help in comparing different fish populations. According to growth and age, the rudd has been divided in four age groups. The first group represents the youngest fish with average growth of L1=11.603 cm, the second group L2=15.921 cm, the third group L3=19.295 cm while the average growth of the fourth group, the oldest one, was L4=19.998 cm. The growth of rudd at a chosen location has been compared to the already published data of rudd growing at other locations. Growth performance at chosen location was around 5 which coincides with the data taken from the literature. This research proves that investigated water of the Klju i brdo“ location is favourable for the growth and the development of rudd.
A Basal Sauropodomorph (Dinosauria: Saurischia) from the Ischigualasto Formation (Triassic, Carnian) and the Early Evolution of Sauropodomorpha  [PDF]
Ricardo N. Martinez, Oscar A. Alcober
PLOS ONE , 2009, DOI: 10.1371/journal.pone.0004397
Abstract: Background The earliest dinosaurs are from the early Late Triassic (Carnian) of South America. By the Carnian the main clades Saurischia and Ornithischia were already established, and the presence of the most primitive known sauropodomorph Saturnalia suggests also that Saurischia had already diverged into Theropoda and Sauropodomorpha. Knowledge of Carnian sauropodomorphs has been restricted to this single species. Methodology/Principal Findings We describe a new small sauropodomorph dinosaur from the Ischigualsto Formation (Carnian) in northwest Argentina, Panphagia protos gen. et sp. nov., on the basis of a partial skeleton. The genus and species are characterized by an anteroposteriorly elongated fossa on the base of the anteroventral process of the nasal; wide lateral flange on the quadrate with a large foramen; deep groove on the lateral surface of the lower jaw surrounded by prominent dorsal and ventral ridges; bifurcated posteroventral process of the dentary; long retroarticular process transversally wider than the articular area for the quadrate; oval scars on the lateral surface of the posterior border of the centra of cervical vertebrae; distinct prominences on the neural arc of the anterior cervical vertebra; distal end of the scapular blade nearly three times wider than the neck; scapular blade with an expanded posterodistal corner; and medial lamina of brevis fossa twice as wide as the iliac spine. Conclusions/Significance We regard Panphagia as the most basal sauropodomorph, which shares the following apomorphies with Saturnalia and more derived sauropodomorphs: basally constricted crowns; lanceolate crowns; teeth of the anterior quarter of the dentary higher than the others; and short posterolateral flange of distal tibia. The presence of Panphagia at the base of the early Carnian Ischigualasto Formation suggests an earlier origin of Sauropodomorpha during the Middle Triassic.
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