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31.
The sedimentary succession exposed in the Gorzów Wielkopolski area includes Eemian Interglacial (MIS 5e) or Early Weichselian (MIS 5d–e) deposits. The sedimentary sequence has been the object of intense interdisciplinary study, which has resulted in the identification of at least two palaeolake horizons. Both yielded fossil remains of large mammals, alongside pollen and plant macrofossils. All these proxies have been used to reconstruct the environmental conditions prevailing at the time of deposition, as well as to define the geological context and the biochronological position of the fauna. Optically stimulated luminescence dating of the glaciofluvial layers of the GS3 succession to 123.6 ± 10.1 (below the lower palaeolake) and 72.0 ± 5.2 ka (above the upper palaeolake) indicate that the site formed during the Middle–Late Pleistocene (MIS 6 – MIS 5). Radiocarbon-dating of the lacustrine organic matter revealed a tight cluster of Middle Pleniglacial Period (MIS 3) ages in the range of ~41–32 ka cal bp (Hengelo – Denekamp Interstadials). Holocene organic layers have also been found, with 14C ages within a range of 4330–4280 cal bp (Neolithic). Pollen and plant macrofossil records, together with sedimentological and geochemical data, confirm the dating to the Eemian Interglacial.  相似文献   
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 An evaluation of the influence of channel processes (erosion, accumulation, processing of channel sediments) on the dispersal of heavy metals in bottom sediments was carried out in the channels of the Sztoła and Biała Przemsza rivers in Upper Silesia, Poland. These rivers receive waters from a Zn and Pb mine. Mine waters transport a large amount of fine-grained sediments contaminated with heavy metals. The polluted material is accumulated in these stream courses and mixed with nearly homogeneous sandy sediment derived from erosion of the river banks and bed. Because these alluvia are easily set in motion, the distribution of heavy metal concentration in the channel in fraction <1 mm reflects differences in physical processes of sedimentation in its cross-section. The minimal values in active channel and maximal in the near-bank zone are typical for those channel sections where heavy metals, present in a solid state, are transported as a suspended load (normally the largest part of a polluted river course). In short sections heavy metals associated with the grains of a large mass which has accumulated in the active channel are transported as a bed load and the typical distribution pattern is reversed (in fractions both <1 mm and <0.063 mm). Such regularities can be disturbed in localities where strong, turbulent flow or frequent eddying occur and Mn oxides and hydrooxides and associated elements precipitate. The smallest variation in heavy metal concentration in the homogenous, fine-grained bank sediments which are trapped by plants below water level is a feature which recommends these localities as being the most suitable for monitoring of river pollution. Received: 11 November 1997 · Accepted: 12 March 1998  相似文献   
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Hydrogeological research was performed to establish the origin of organic-rich water in a Quaternary aquifer (Wielkopolska Buried Valley aquifer, Poland). The spatial distribution of such water was determined by means of multilevel sampling with a packer. The nature, spatial distribution and chemistry of the organic-rich water suggest hydraulic connection between the Quaternary aquifer and the underlying Neogene aquifer. This connection may be enabled by an old abandoned, improperly plugged well, and must therefore be considered as an artificial hydraulic connection between hydrogeologically separated aquifers. For the verification of this hypothesis, a groundwater contaminant transport model was constructed. The results of contaminant transport modeling allow the contaminant transport parameters (transverse and longitudinal dispersivity) to be identified in the field. The numerical groundwater model was used for the prognosis of organic-rich water remediation, and for specification of water-resource management principles in the region where organic-rich water occurs. The results of this research enable the verification of assumptions regarding complex groundwater flow conditions in the boundary zone of a buried valley.  相似文献   
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We revise the conceptual model of calcite varves and present, for the first time, a dual lake monitoring study in two alkaline lakes providing new insights into the seasonal sedimentation processes forming these varves. The study lakes, Tiefer See in NE Germany and Czechowskie in N Poland, have distinct morphology and bathymetry, and therefore, they are ideal to decipher local effects on seasonal deposition. The monitoring setup in both lakes is largely identical and includes instrumental observation of (i) meteorological parameters, (ii) chemical profiling of the lake water column including water sampling, and (iii) sediment trapping at both bi-weekly and monthly intervals. We then compare our monitoring data with varve micro-facies in the sediment record. One main finding is that calcite varves form complex laminae triplets rather than simple couplets as commonly thought. Sedimentation of varve sub-layers in both lakes is largely dependent on the lake mixing dynamics and results from the same seasonality, commencing with diatom blooms in spring turning into a pulse of calcite precipitation in summer and terminating with a re-suspension layer in autumn and winter, composed of calcite patches, plant fragments and benthic diatoms. Despite the common seasonal cycle, the share of each of these depositional phases in the total annual sediment yield is different between the lakes. In Lake Tiefer See calcite sedimentation has the highest yields, whereas in Lake Czechowskie, the so far underestimated re-suspension sub-layer dominates the sediment accumulation. Even in undisturbed varved sediments, re-suspended material becomes integrated in the sediment fabric and makes up an important share of calcite varves. Thus, while the biogeochemical lake cycle defines the varves’ autochthonous components and micro-facies, the physical setting plays an important role in determining the varve sub-layers’ proportion.  相似文献   
36.
The importance of long‐term storage of heavy metals in groyne fields, functioning over 150 years, is investigated for the River Odra (Oder), western Poland. Construction of groynes along the Odra preceded rapid development of heavy industrialization in the largest coal mine districts in Poland and the Czech Republic that resulted in persistent riverine pollution. The 187 km long Middle Odra reach was repeatedly channelized from the first half of the eighteenth century to the turn of the twentieth century, during which time partially filled groyne fields were dissected by new bank lines and groyne systems, with older groyne fields partially keyed into the floodplain. Consequently, concentrations of zinc, lead, cadmium, and copper within historically deposited groyne field sediments exceed local geochemical background levels by more than 60, 40, 15 and 10 times, respectively. Sediments contaminated with heavy metals occur within three distinctive geomorphic zones: zone I is up to 250 m wide and furthest from the present channel, comprising decimeter‐thick polluted sediments, overlying eighteenth century sand and gravel bars; zone II represents the former nineteenth century groyne fields, with widths between 10 and 100 m, filled with as much as 3 m of polluted sediments; zone III represents the twentieth century groyne fields, which are several to a dozen metres wide and filled with polluted sediments averaging depths of more than 2 m. This investigation indicates that large and extensive sediment quantities of moderately polluted sediments are stored immediately along the banks of the River Odra. These sediments could be a significant secondary pollution source and therefore careful maintenance of contemporary bank protection structures is required. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
37.
The paper deals with the problem of SH harmonic wave propagation in an elastic layer with temperature dependent properties. The shear modulus and mass density are linearly dependent on temperature. The layer is rested on a rigid foundation and the upper boundary is free of loadings. The boundary planes are kept at different constant temperatures. The wave velocity and amplitude of stresses are analysed.  相似文献   
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This paper analyses the possibility of using integrated GPS (Global Positioning System) surveys and ground penetrating radar surveys to precisely locate damages to levees, particularly due to the activity of small fossorial mammals. The technology of intercommunication between ground penetrating radar (GPR) and an RTK (Real-Time Kinematic) survey unit, and the method of data combination, are presented. The errors which may appear during the survey work are also characterized. The procedure for processing the data so that the final results have a spatial character and are ready to be implemented in digital maps and geographic information systems (GIS) is also described.  相似文献   
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