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1.
Radovan Pipík Anne-Marie Bodergat Danielle Briot Michal Ková? Ján Král’ Grzegorz Zielinski 《Journal of Paleolimnology》2012,47(2):233-249
The Turiec Basin (TB) of Slovakia formed in the Miocene when the West Carpathians escaped from the Alpine region. The 1,250-m-thick
sedimentary Neogene fill of the basin preserved fossil leaves as well as endemic bivalves, gastropods, and ostracodes. The
paleolimnologic changes recorded in the TB infill were derived from the most abundant fossils, the ostracodes. Five contemporaneous
ostracode assemblages within the Late Miocene lacustrine system were distinguished through statistical analysis. These assemblages
have low species similarity, between 2.1 and 24.1%, and are recognized by shape differences among the Candoninae. The ostracode
assemblages, mollusca fossils, and Sr-isotope ratios suggest a low-salinity environment at the beginning of the Late Miocene,
during a brief connection with the Central Paratethys. When the connection ceased, the basin became an isolated freshwater
lake, with five zones differentiated ecologically and bathymetrically using the ostracode assemblages. Taxonomic comparison
of the faunas of the TB and the freshwater to brackish Neogene basins of Europe demonstrates the endemic character of the
TB ostracode fauna. The biologic characteristics of the ostracode families, along with the geology of the lake basin, suggest
that the longevity of the Late Miocene lake probably exceeded 1 Ma. 相似文献
2.
István Cziczer Imre Magyar Radovan Pipík Madelaine Böhme Stjepan Ćorić Koraljka Bakrač Mária Sütő-Szentai Miklós Lantos Edit Babinszki Pál Müller 《International Journal of Earth Sciences》2009,98(7):1741-1766
Life and depositional environments in the sublittoral zone of Lake Pannon, a large, brackish Paratethyan lake from the Late
Miocene, were reconstructed from fossils and facies of the Szák Formation. This formation is exposed in several, roughly coeval
(9.4–8.9 Ma) outcrops, located along strike of the paleo-shelf-break in northwestern Hungary. The silty argillaceous marl
of the formation was deposited below storm wave base, at 20–30 to 80–90 m water depth. The abundance of benthic organisms
indicates that the bottom water was usually well oxygenated. Interstitial dysoxia, however, may have occurred immediately
below the sediment–water interface, as evidenced by occasional preservation of trace fossils such as Diplocraterion. The fauna comprised endemic mollusks, including brackish cockles of the subfamily Lymnocardiinae, dreissenid mussels (Congeria), and highly adapted, uniquely large-sized deep-water pulmonate snails (planorbids and lymnaeids). Ostracods were dominated
by endemic species and, in some cases, endemic genera of candonids, leptocytherids, cypridids, and loxoconchids. Fish remnants
include a sciaenid otolith and the oldest skeletal occurrence of Perca in Europe. The phytoplankton comprised exclusively endemic coccolithophorids, mostly endemic dinoflagellates (prevailingly
Spiniferites), and cosmopolitan green algae. The Late Miocene fauna and flora of Lake Pannon were in many ways similar to the modern Caspian
biota, and in particular cases can be regarded as its precursor. 相似文献
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Nenad Grujovic Dejan Divac Miroslav Zivkovic Radovan Slavkovic Nikola Milivojevic Vladimir Milivojevic Dragan Rakic 《Acta Geotechnica》2013,8(3):265-278
The mechanical behaviour of a rock mass is described in this paper using a method that combines experimental and numerical techniques. A new discontinuity (joint) constitutive model is proposed based on the non-associative yield law. Constitutive relationships for an anisotropic rock mass are determined by introducing an interaction between sets of discontinuities and the monolith in which they occur. The model is based on the concept that deformation of the monolith and its associated sets of discontinuities are coupled. An experimental investigation of the concrete foundations of the Bogovina Dam on the Crni Timok River in Serbia has been used to verify the presented numerical model. The tests included discontinuity and monolith sample investigations and large-scale field tests. 相似文献
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6.
Pavle Tan?i? Predrag Vuli? Reinhard Kaindl Bernhard Sartory Radovan Dimitrijevi? 《《地质学报》英文版》2012,86(2):394-405
The macroscopically-zoned grandite from the garnetite skarn of Meka Presedla (Kopaonik Mountain, Serbia) was studied with optical microscopy, electron microprobe analysis (EMPA), Fourier transform infra-red (FT–IR), and Raman methods. The EMPA results indicate that the main core–rim compositional variations (Ca2.93–2.97Mn0.05–0.06Mg0.00–0.01Al1.14–1.26Fe3+0.72–0.83Ti0.00–0.02Si2.97–3.02O12) slightly differ along the zones, showing evidence for a quasi-cyclic alternation of the oscillatory zoning nature. Among this, considerable variation is observed only by the Al–Fe3+ substitutions in the octahedral site. The EMPA also indicate that the grandite zones compositionally vary, mostly within ±1 and ±2 mol% of the homogeneity level range, that is, Grs64±1Adr36±1Sps2 (A), Grs62±1Adr38±1Sps2 (B), Grs59±2Adr40±2Sps2 (C), Grs58±2Adr41±2Sps2 (D), and Grs58±1Adr41±1Sps2 (E). Therefore, the investigated garnet can be considered as relatively highly homogeneous. The majority of compositions lie within the narrow miscibility region of 0.58±2相似文献
7.
Pavle TAN?I? Radovan DIMITRIJEVI? Maja POZNANOVI? Aleksandar PA?EVSKI Slobodanka SUDAR 《《地质学报》英文版》2012,86(6):1524-1538
The crystal structure of ludwigite from Vranovac ore deposit (Boranja Mt., Serbia) was refined using the X-ray powder diffraction (XRPD) Rietveld method in the space group Pbam to a final RB=7.45% and RF=5.26%. It has the unit cell dimensions of: a=9.2515(2) ?; b=12.3109(2) ?; c=3.03712(7) ?; and V=345.91(1) ?3. The calculated distances and angles are mostly in good agreement with the Mg2+-Fe2+ substitutions across the M(1) and M(3) sites, as well as with the Fe3+-Al3+ replacement in the M(4) site. However, the mean observed M(2)-O distance is considerably shorter than prescribed, due to a slight increase of the Fe3+ content in the M(2) site. Such replacement was compensated by slight increase of the Fe2+ content in the M(4) site, resulting in the (Mg1.48Fe2+0.46Fe3+0.05Mn0.02)2.01(Fe3+0.94Fe2+0.04Al0.02)1.00B1.00O5 composition. The formation temperature was estimated to be about 500–600°C. The influences of the various chemical compositions to the crystallographic parameters, M-O distances, M(3) and M(4) sites shift, distortion parameters and estimated valences, were also studied and compared with other reference samples. 相似文献
8.
Fifty-two ostracod taxa were identified from two sediment cores collected from the early Badenian ?idlochovice stratotype. Ostracod assemblages were analyzed with a focus on taxonomy, paleoecology, distribution of taxa along the sediment cores, quantification of valve/carapace ratios, and species richness by Simpson??s Reciprocal Index. The changes in ostracod assemblages identified in these cores reflect a shallowing of the marine water-depth from circalittoral/epibathyal to shallow infralittoral, and an increase in the sedimentation rate upwards through time. A comparison of all Badenian ostracod assemblages in the Carpathian Foredeep indicates a high proportion of deep-water ostracod species in ?idlochovice and its surroundings, suggesting that the deepest part of the Carpathian Foredeep was probably situated in this part of the Czech Republic. 相似文献
9.
Em? Márton Bruno Tomljenovi? Davor Paveli? Mihály Pethe Radovan Avani? Bogomir Jelen 《International Journal of Earth Sciences》2012,101(3):879-888
The magnetic fabric of Late Miocene sediments from the southern Pannonian basin was studied on oriented samples collected
from 19 geographically distributed localities. All of them are characterized by near-horizontal magnetic foliation plane after
tilt correction, indicating weak deformation. Well-developed lineations were observed for 16 localities, which are interpreted
as due to compressional/transpressional deformation, except from three localities, where the fabric must have been formed
in an extensional setting. Comparison between the orientation of the map-scale folds and faults and magnetic lineation directions
shows that magnetic lineation is either related to NNE-SSW directed compression, leading to the formation of folds or it can
be connected to NW–SE or NNE-SSW trending dextral faults. 相似文献
10.
Emö Márton Davor Pavelić Bruno Tomljenović Radovan Avanić Jakob Pamić Péter Márton 《International Journal of Earth Sciences》2002,91(3):514-523
In northern Croatia, the Neogene sediments cover complicated basement rocks which consist of Alpine and Dinaridic elements in the Zagorje area, and Variscan - Alpine formations of the Tisia (Tisza) megatectonic unit in the Slavonian Mountains (Mts.). The Neogene sediments were deposited in two separate basins before the Karpatian, but sedimentation became uniform from the Karpatian onwards (~17.5 Ma). Of the 24 localities that we have studied so far paleomagnetically from northern Croatia, 16 localities are of Karpatian or younger age, while the rest are pre-Karpatian. As a result of laboratory analysis, 16 localities yielded tectonically interpretable results. Our data suggests that northern Croatia shifted northwards, while rotating moderately counterclockwise, probably before the Karpatian. A second counterclockwise rotation occurred at the present latitude in post-Pontian times. There is no significant difference between localities situated above different basements, though Tisia is pictured as rotating clockwise in the Neogene. The paleomagnetic pattern of northern Croatia resembles that of areas situated north of the Periadriatic-Balaton line. Therefore, we conclude that northern Croatia is part of a larger block, dissected by several important tectonic lines, driven by the counterclockwise rotated Adriatic microplate. 相似文献