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61.
Middle and Late Pleistocene fluvial systems in central Poland   总被引:1,自引:0,他引:1  
This reconstruction of the fluvial palaeogeography of central Poland is based on an exhaustive and critical review of the published and archival data for the Middle and Late Pleistocene sediments of the area. The Warsaw Basin in central Poland was a major confluence area during the Middle and Late Pleistocene. The fluvial watersheds have been only slightly modified since that time. The past river systems resembled the contemporary one, therefore indicating rebuilding during successive interglacials, at least since the Holsteinian when the sea undoubtedly occupied the southern Baltic Basin. The Weichselian fluvial system was strongly influenced by the Scandinavian ice sheet, especially by meltwater runoff in the extraglacial area and ice-damming in the Warsaw Basin where a large proglacial lake developed. The Weichselian fluvial sediments form up to three terraces in the valleys of the Vistula and its tributaries. The most contentious issue is the mutual relation of the ice-dammed lake and ice marginal spillways in the Warsaw Basin, both being important fragments of a widespread drainage network in the Central European Lowland.  相似文献   
62.
A 3D structural modelling of the Permian–Mesozoic Polish Basin was performed in order to understand its structural and sedimentary evolution, which led to basin maturation (Permian–Cretaceous) and its tectonic inversion (Late Cretaceous–Paleogene). The model is built on the present-day structure of the basin and comprises 13 horizons within the Permian to Quaternary rocks. The analysis is based on 3D depth views and thickness maps. The results image the basin-scale symmetry, the perennial localization of the NW–SE-oriented basin axis, the salt movements due to tectonics and/or burial, and the transverse segmentation of the Polish Basin. From these observations, we deduce that salt structures are correlated to the main faults and tectonic events. From the model analysis, we interpret the stress conditions, the timing, and the geometry of the tectonic inversion of the Polish Basin into a NW–SE-oriented central horst (Mid-Polish Swell) bordered by two lateral troughs. Emphasis is placed on the Zechstein salt, considering its movements during the Mesozoic sedimentation and its decoupling effect during the tectonic inversion. Moreover, we point to the structural control of the Paleozoic basement and the crustal architecture (Teisseyre–Tornquist Zone) on the geometry of the Polish Basin and the Mid-Polish Swell.  相似文献   
63.
This paper analyses the influence of mining on hydrological conditions in Upper Silesia from the fifteenth to the nineteenth centuries. The perturbation of local hydrological conditions began in the fifteenth century as a result of wide-scale mining of iron, silver and lead ores. Further changes took place during the sixteenth and seventeenth centuries, following the application of gravitational mine drainage. As a result, a compact cone of depression, covering an area of about three square kilometres was created. In the eighteenth century, the activities of mills, sawmills and smelters caused considerable changes in the surface river network and created the so-called anthropogenic Upper Silesian Lakeland. At the end of the eighteenth century, underground mining activity was renewed and as a result the area of the compact cone of depression increased to ten square kilometres and its depth reached 50 metres.  相似文献   
64.
Periglacial slope covers in the southern part of the Cracow Upland, S Poland can be grouped in five genetic categories: slope loess, washed loess, weathered debris, scree deposits, low-density flow deposits, and solifluctites or high-density flow deposits. They differ from each other with respect to their morphological position in relation to the slope, and in lithological characteristics. It was found that successive generations of slope deposits can be distinguished according to their degree of chemical weathering, which can be estimated on the basis of the presence and morphology of limestone clasts, on the content and colour of the colloid clay, and on the Fe2O3 and CaCO3 content of the clay particles.This paper contributes to a discussion on the possibility of palaeoclimate reconstruction based on slope deposits analyses.  相似文献   
65.
The paper analyses a list of thirty-four Poles, listeners to the mineralogy lectures given by R.-J. Haüy at MNHN in Paris. These students played an important role in the history of Polish Earth Sciences (S. Staszic and F. Drzewiński), but also in other scientific fields (J. Markowski, I. Ab?amowicz, F. Drzewiński, M.A. Paw?owicz, J.K. Skrodzki, E.K. Nowicki), and even in political and cultural life of Poland (A. Downarowicz, J. Weyssenhoff, S. Plater, J. Bieliński, F. Potocki). This paper presents later relations between R.-J. Haüy and his Polish students. A possibility of the Poles' attendance to mineralogy lectures given at other Parisian scientific institutions, like the ‘École des mines’ and the ‘College de France’, is also discussed. To cite this article: R. Tarkowski, P. Daszkiewicz, C. R. Geoscience 338 (2006).  相似文献   
66.
The Silesian Upland is one of the most degraded areas in Poland owing to the long‐lasting influence of mining and metallurgy. Mining influences every component of the environment in significant and diverse ways. But even in such a devastated terrain there is evidence of the proper management of post‐mining areas and natural self‐restoration, which paradoxically, owing to mining, appear in the most intensively used economic areas. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
67.
This article presents the results of a geochemical investigation of sediments from Lake Druzno (northern Poland), a reservoir fed by freshwater from the catchment, with periodic input of brackish water from Vistula Lagoon. This study analyzed the spatial variation in heavy metal content in surface sediments as well as the temporal changes in metal content in two sediment cores dated using the 210Pb method. In the surface sediments, the highest metal concentrations were recorded in the northern part of the lake, with lower concentrations in the central and southern parts. Absolute values of metal concentrations in the cores were low, but normalization with respect to Al showed an increase during the second half of the 20th century. Mean enrichment factors (EF) in sediments from the second half of the 20th century ranged from insignificant (1–1.2) for Fe to (1.55–3.3) for Cu, Cd, Pb and Zn. The sediments deposited before 1950 had lower EF values (>1.5) and had low variability. Results from both the surface sediments and the cores indicate that the main source of lake pollution is brackish water intrusion from the Vistula Lagoon via the contaminated River Elbląg.  相似文献   
68.
69.
The implementation of the Belt and Road Initiative and the increasing frequency of the China-Europe Railway Express(CER Express)have brought new improvement to the production system of enterprises along the Belt and Road regions.On the basis of summa-rizing the evolution of production system of enterprises,this paper takes TCL Poland Plant as an example to conduct an in-depth study on the characteristics of the plant's current produc-tion system and its differences from the original production system,and analyzes the impact of the CER Express on its current production system.Some conclusions can be drawn as follows.(1)CER Express had a great impact on the production system of TCL Poland Plant,which is mainly manifested in the following aspects.First,the transport of raw materials by CER Express improves the time efficiency and shortens the whole supply chain.Second,CER Express acts as a"moving inventory",which realizes the flexibility of raw material in-ventory and"zero inventory"effect based on the punctual transport.Third,the time and in-ventory effects brought by CER Express speed up the response to European market.The comprehensive benefits brought by CER Express lead to a more punctual and lean produc-tion system,meet the diversified needs of consumers on account of product quality and di-versification,and improve ability to expand European market.(2)On the basis of abandoning the original"Rigid Mass Production"system,we argue that TCL Poland Plant formed a unique production system—"Global Fluid Just-in-Time"which absorbed the essence of Toyota Pro-duction System based on the punctual transnational transportation of CER Express.(3)The differences between the current and the original production systems of TCL Poland Plant are mainly focused on the following aspects:the difference of transport and storage mode of raw materials,and the changes of production line,production mode and quality inspection or-ganization,etc.  相似文献   
70.
Tuna Tasan 《GeoJournal》1999,49(1):91-103
The aim of this paper is to show how and in what sense the post-socialist transformation process has influenced the urban spatial structure of Warsaw with the help of empirical evidence dealing with housing. Therefore, the main focus of the study is the transformation of the housing market in the 1990s under social and economic restructuring process. The article comprises two parts: the first part involves the geographical development of the urban spatial structure within the context of housing market changes. In order to explain today's transformation, the system of socialist time is also discussed. In the second part emphasis is placed on the evidence of the transformation in urban space, dealing with new tendencies and challenging mechanisms in the housing market. The last period of transformation is also investigated in terms of changes in the urban space since housing is seen as an important factor of urban transformation. Hence, following the brief outline of historical development of the urban space housing market changes including the privatization of urban land is going to be the concern of the paper. The problems of the transformation and practical implementation of the privatization process are also discussed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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