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Jarmila Slánská 《Sedimentary Geology》1976,15(2):135-164
Tectonic activity, climatic changes and associated weathering cooperated during the formation of Upper Cretaceous red beds of the South Bohemian Basins known as the Klikov Formation.The sediments are clastic and comprise: (1) light-grey or yellow conglomeratic, course-to-medium sandstone beds; (2) generally finer red beds; and (3) grey beds. They alternate in asymmetrical cycles, in succession fining upwards. Small- and large-scale cyclothems were recognized. The large-scale cyclothems are closely connected with paleogeographical changes and tectonic evolution of the South Bohemian Basins in Early Senonian time. In regard to rapid vertical and lateral lithological variations, the common presence of graded bedding, poor sorting and lack of fossils, the sediments are comparable to the fluviatile facies of molasse, known as “flysch in molasse”. They were deposited from highly fluctuating currents and periodically overloaded streams in an alluvial and/or lacustrine environment, suffering continuously from tectonic unrest emanating from the Alpine—Carpathian geosyncline.Differences between red and grey sediments are related mostly to the primary distribution and preservation of organic matter and to some extent to the redistribution of iron during early diagenetic changes (e.g. red stains).Ancient weathered gneiss and granite profiles preserved beneath the sediments show development of either two (on granite) or three (on gneiss) horizons differing in degree of weathering and distribution of red colour within the profiles. The trend of weathering documented by chemical analyses and presence of kaolinite as the end-product points to the red podzolic soil formation process. 相似文献
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Rüdiger Glaser Dirk Riemann Johannes Schönbein Mariano Barriendos Rudolf Brázdil Chiara Bertolin Dario Camuffo Mathias Deutsch Petr Dobrovolný Aryan van Engelen Silvia Enzi Monika Halíčková Sebastian J. Koenig Oldřich Kotyza Danuta Limanówka Jarmila Macková Mirca Sghedoni Brice Martin Iso Himmelsbach 《Climatic change》2010,101(1-2):235-256
The paper presents a qualitative and quantitative analysis of flood variability and forcing of major European rivers since AD 1500. We compile and investigate flood reconstructions which are based on documentary evidence for twelve Central European rivers and for eight Mediterranean rivers. Flood variability and underlying climatological causes are reconstructed by using hermeneutic approaches including critical source analysis and by applying a semi-quantitative classification scheme. The paper describes the driving climatic causes, seasonality and variability of observed flood events within the different river catchments covering the European mainland. Historical flood data are presented and recent research in the field of historical flood reconstructions is highlighted. Additionally, the character of the different flood series is discussed. A comparison of the historical flood seasonality in relation to modern distribution is given and aspects of the spatial coherence are presented. The comparative analysis points to the fact that the number of flood events is predominately triggered by regional climatic forcing, with at most only minor influence on neighbouring catchments. The only exceptions are extreme, supra-regional climatic events and conditions such as anomalous cold winters, similar to that of 1784, which affected large parts of Europe and triggered flood events in several catchments as a result of ice-break at the beginning of the annual thaw. Four periods of increased occurrence of flooding, mostly affecting Central European Rivers, have been identified; 1540–1600, 1640–1700, 1730–1790, 1790–1840. The reconstruction, compilation and analysis of European-wide flood data over the last five centuries reveal the complexity of the underlying climatological causes and the high variability of flood events in temporal and spatial dimension. 相似文献
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Milan Gomboš Andrej Tall Jarmila Trpčevská Branislav Kandra Dana Pavelkova Lucia Balejčíková 《Arabian Journal of Geosciences》2018,11(20):635
The aim of the submitted paper is to identify the lower limit of Stokes’ law for calculating the deposition rate of soil microparticles. The authors’ hypothesis on the lower limit of Stokes’ law is based on the idea that with the gradual formation of the colloidal dispersion system, both the particle size and the sedimentation rate decrease. It is assumed that under the lower particle size limit, Stokes’ law does not apply. As a result of the diffusion, the state of the sedimentation equilibrium gradually emerges. The results of the experiment showed that in laboratory conditions, Stokes’ equation ceases to be valid for sedimentation of the particles sized d(90)?<?2 μm. During the experiment, a dynamic sedimentation equilibrium was reached at the particle size d(90)?=?0.27 μm. The scientific contribution of this knowledge is the accuracy of the determination of hydropedological characteristics dependent on the texture of the soil. In this context, the results stated in the paper define the lower limit of the validity for the laboratory procedures determining soil texture on the basis of the sedimentation methods. To identify the textures below this limit, it is necessary to choose the methods based on other principles. Determination of the lower limit is particularly important in clay soils containing a high proportion of clay particles (clay particles <?2 μm). 相似文献
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Petr Dobrovolný Anders Moberg Rudolf Brázdil Christian Pfister Rüdiger Glaser Rob Wilson Aryan van Engelen Danuta Limanówka Andrea Kiss Monika Halíčková Jarmila Macková Dirk Riemann Jürg Luterbacher Reinhard Böhm 《Climatic change》2010,101(1-2):69-107
Monthly temperature series for Central Europe back to AD 1500 are developed from documentary index series from Germany, Switzerland and the Czech Republic (1500–1854) and 11 instrumental temperature records (1760–2007). Documentary evidence from the Low Countries, the Carpathian Basin and Poland are used for cross-checking for earlier centuries. The instrumental station records are corrected for inhomogeneities, including insufficient radiation protection of early thermometers and the urban heat island effect. For overlapping period (1760–1854), the documentary data series correlate with instrumental temperatures, most strongly in winter (86% explained variance in January) and least in autumn (56% in September). For annual average temperatures, 81% of the variance is explained. Verification statistics indicate high reconstruction skill for most months and seasons. The last 20 years (since 1988) stand out as very likely the warmest 20-year period, accounting for the calibration uncertainty and decreases in proxy data quality before the calibration period. The new reconstruction displays a previously unobserved long-term decrease in DJF, MAM and JJA temperature variability over last five centuries. Compiled monthly, seasonal and annual series can be used to improve the robustness of gridded large-scale European temperature reconstructions and possible impact studies. Further improvement of the reconstruction would be achieved if documentary data from other European countries are further developed. 相似文献
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In the Czech and Polish parts of the Upper Silesian Coal Basin, red beds associated with the pre-Neoide tectonic structures are found. The occurrence of these beds is connected with changes in the development of the coal seams, in the macroscopic and microscopic character of coal and with its chemical and technological properties. These changes are due to the thermal and oxidation alteration of coal as a result of geological processes which, up to now, have not been clarified unambiguously. These altered coals were divided into groups according to their chemical and physical properties and vitrinite reflectance using statistical multicomponent methods. Coal samples classified as belonging to one of these groups correspond to a certain type of coal, characterized by a particular grade of thermal and oxidation alteration and petrographical composition. 相似文献
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