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Farkas-Peto A.,Debrecen University | Horvath T.,Hungarian Academy of Sciences | Papp I.,Debrecen University | Kovacs-Palffy P.,Hungarian Geological and Geophysical Institute
Carpathian Journal of Earth and Environmental Sciences

With the analysis of the middle Bronze Age (2000-1350 BC) Vatya culture findings in Pest county (Central Hungary) comprising of more than 400 polished stone tools and instrument tools this is the first archaeometric study with such scale in Hungary. In order to characterize petrographically the raw-material of the stone tools macroscopic and microscopic stone analyses were made together with mineralogical and geochemical analyses. In the course of the work a new digital database the Archaeometric Stone Tool Database was established. Based on the results, the material of the instrument stones is mainly sandstone and quartzite that were easy to collect from their source areas. Local volcanics, mostly amphibole containing andesite variations dominated among the material of the polished stone tools. Ophiolites (metamorphic basic rocks, serpentinized basic and ultrabasic rocks) were the raw-material of stone axes that indicate either more distant travels for raw-material or exchange import. Source

Xia Q.-K.,Hefei University of Technology | Liu J.,Hefei University of Technology | Liu S.-C.,Hefei University of Technology | Kovacs I.,Hungarian Geological and Geophysical Institute | And 2 more authors.
Earth and Planetary Science Letters

It has been suggested that the longevity of cratons (i.e. ancient and stable cores of continents) is related in part to the low water content of their deep mantle roots; this gives them a higher viscosity than the underlying asthenosphere. Consequently, the removal of cratonic roots is expected to be closely connected to the hydration of the lithospheric mantle, but direct evidence for this speculation has been scarce. The eastern part of the North China Craton (NCC) is a clear example of a "destroyed craton". In this study the H2O content of clinopyroxene phenocrysts was measured in lithospheric mantle-derived high-magnesium basalts of the Feixian area, in the eastern part of the NCC. These lavas erupted in the early Cretaceous (~120Ma), which was the peak time of the NCC destruction. Based on these data, it was estimated that the H2O content of the lithospheric mantle source of these basalts consists of more than 1000ppm by weight. This water content is much higher than in the source of mid-ocean-ridge basalts (50-200ppm by weight) and also higher than in the Kaapvaal cratonic mantle in South Africa (~120ppm by weight); the latter is still stable after >3 billion years. This study argues that a large amount of water was indeed added to the NCC's lithospheric mantle, probably due to the multi-stage subduction of oceanic plates since the early Paleozoic. This high water content significantly reduced the viscosity contrast between the lithospheric mantle and the underlying asthenosphere, and provided a prerequisite for the removal of the cratonic root of the NCC by reducing its strength. © 2012 Elsevier B.V. Source

Fuleky G.,Szent Istvan University | Kalmar J.,Hungarian Geological and Geophysical Institute
Carpathian Journal of Earth and Environmental Sciences

The Kömlo model area is a 250?250 m sized agricultural field in the central part of the Great Hungarian Plain. In this paper, the geological background, the hydrogeology of the area and the distribution of nutrients and trace elements of different soil levels were studied. The soil, which was formed on the clayey-silty floodplain and the sandy riverbed sediments of the old River Tisa was sampled in 25 boreholes (4 genetic levels, 108 samples) and the samples were analyzed for 23 main and trace elements. Among them, tree groups of elements were recognized: the main, rock forming elements, the trace elements of which concentration up to 1 ppm and some elements with concentrations below 1 ppm, close to the detection limit. The concentration of elements and the relation among them depend on the sediment type, on the soil level and on the presence of the groundwater table, while the areal distribution of some trace elements in the ploughed and in the root zones indicates the stream direction of the sediments during the past floods of the river Tisa. Source

Barbacka M.,Hungarian Natural History Museum | Barbacka M.,Polish Academy of Sciences | Bodor E.,Hungarian Geological and Geophysical Institute | Bodor E.,Eotvos Lorand University | And 8 more authors.
Acta Palaeobotanica

The Jurassic floras of Europe show considerable diversity. To examine the extent of this diversity and its possible causes we used multivariate statistical methods (cluster analysis, PCA, NMDS) to compare all significant Jurassic floras in Europe. Data were based on 770 taxa from 46 fossiliferous occurrences (25 units) from France, Germany, Greenland, Hungary, Italy, Norway, Poland, Romania, Scotland, Serbia, Sweden, Switzerland, and the United Kingdom. Statistical analyses were applied at species level and genus level, and also performed for the major plant groups. The genus cladograms show affinities between different localities based on environmental factors, while the cladograms based on species affinities indicate only taxonomical correlations. The study shows that locality age does not seem to be of paramount importance for floral composition. Source

Barbacka M.,Hungarian Natural History Museum | Barbacka M.,Polish Academy of Sciences | Popa M.E.,University of Bucharest | Mitka J.,Jagiellonian University | And 3 more authors.
Acta Palaeobotanica

Two Early Jurassic localities, the Mecsek Mts in Hungary and Anina in Romania, are similarly significant and both floras are of autochthonous/paraautochthonous origin. In the Early Jurassic the Hungarian locality was a delta plain; the Romanian locality was an intramontane depression filled predominantly by a braided river system. The floristic composition of the two localities (52 genera, 120 species), although superficially similar (25 common genera), differs at species level (only 9 common species) as well as in the proportions of taxa in major plant groups. These differences can be explained by differences in environmental conditions resulting from palaeogeographic and topographic factors. Based on previous and recent studies, alpha diversity as well as statistically (DCA, PCA) differentiated ecogroups are compared and discussed. For common species, the GLM method was used to classify them to particular environmental response types. Their environmental requirements in both ecosystems are evaluated. Some of the shared species showed different preferences at the localities, explainable by their broad ecological tolerance. Source

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