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KRZYSZTOF BIK JERZY NITYCHORUK 《Boreas: An International Journal of Quaternary Research》2001,30(4):307-316
Taking a palynological study from Dziewule in eastern Poland as an example, we discuss the problem of distinguishing the so-called 'Zeifen-Kattegat oscillation' in some European pollen profiles. In the light of pollen analysis, this is questionable, and therefore requires careful consideration. In Poland, the palynological succession from this period indicates a gradual evolution from open plant communities to a closed forest in which no record of a 'Younger Dryas' type cool event exists. 相似文献
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Oxygen consumption by rotifers Macrotrachela musculosa and Trichotria truncata from Spitsbergen tundra (77°N) was measured using the method of Cartesian divers. The metabolic rate of M. musculosa was: 0.205 10−3 mm3 02 per g 10−6 per hour at 2°C, 0.201 10−6 mm3 at 6°C and 0.616 10−3 mm3 02 per g 10−6 per hour at 10°C. The metabolic rate of Trichotria truncata at 6° was 0.103 10−3 mm3 per g 10−6 per hour. The relation between body weight and oxygen consumption by M. musculosa at 2°C is expressed with the equation R = 0.18W0.67 , with R – oxygen consumption in mm3 10−3 per individual per hour and W – wet weight of an animal in g 10−6 . 相似文献
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A piston core from the basinal part (depth of 5188 m) of the South Shetland Trench (West Antarctica) yielded a terrigenous mud section 11 m long, which can be subdivided with great precision into turbidite and hemipelagite layers. Mud turbidites (mean bed thickness = 44 cm) alternate regularly with, and are best distinguishable from, their hemipelagite host (mean bed thickness = 17 cm) by the following features: (i) sharp basal contacts; (ii) terrigenous sand-free textures (except basal, well-sorted silt laminae) and the absence of outsized (ice-rafted) components; (iii) a laminated, little to non-bioturbated internal structure; (iv) distinct textural and compositional grading; and (v) marked steps on water-content and sediment-density logs. Mud turbidites recovered from the South Shetland Trench differ from an earlier model mud-turbidite sequence by their: (i) excessive (about six times larger) bed thickness; (ii) complex internal organization, manifested in multiple repetitions (up to four) of the same structural interval(s) in sequential or nonsequential order; (iii) distinctive very fine-grained cap of highly porous clay, rich in fragments of siliceous biogenics; (iv) widespread zones of penesyndepositional deformation; and (v) evidence of flow reversals. These features are interpreted to record deposition from large, muddy turbidity currents subjected to flow transformations, including soliton- and/or seiche-related reversals, induced by ponding and interactions of the flow with the topographical confinements of the trench. It is concluded that‘contained’muddy turbidites cannot be adequately modelled using published sequences. Differentiation of single-model and‘contained’mud turbidites offers obvious advantages in basin analysis and in understanding the plethora of turbidity current-related depositional mechanisms of deep-sea mud. 相似文献
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Abstract The flood that occurred in summer 1997 in Poland, affecting the drainage basins of the Odra and the Vistula, caused 54 fatalities and material losses of the order of billions of US$. The flood struck a large part of the country and caused inundation of 665 000 ha of land. The number of evacuees was 162 thousand. The rhetoric commonly used in Poland refers to the Great Flood of 1997 as an event whose scale exceeded all imagination about the possible size of the disaster. Indeed, historic maxima of river stage and flow rate were considerably exceeded. From the hydrological point of view, this flood was a very rare event, with a return period in some river cross-sections of the order of a thousand years and more. As this natural disaster, striking a dynamically developing country-in-transition, attracted much international interest, a holistic view of it is presented. Attempts to answer the questions: “Could the disaster have been avoided?” and “What lessons can be learnt from the flood?” are also made. 相似文献
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MARCIN SZYMANEK JERZY NITYCHORUK JERZY TRAMMER KRZYSZTOF BI&#;KA 《Boreas: An International Journal of Quaternary Research》2005,34(3):335-344
Sediments of palaeolakes located in eastern Poland represent the Holsteinian (Mazovian) Interglacial, which corresponds to the Marine Isotope Stage 11 (MIS 11). Some of these sediments are characterized by an extremely rich occurrence of mollusc shells. A total of 1795 specimens of the snail Viviparus diluvianus were measured from 5 samples collected from a succession of lake deposits at Ortel Krolewski. The sample from the lowermost part of the succession (2.5 m) represents the Picea-Alnus pollen zone of the Holsteinian Interglacial. Samples from 2.0, 1.5, 1.0m are related to the Taxus Zone. Samples collected from the uppermost part of the succession (0.5 m) correspond to the Pinus Zone representing the so-called intra-interglacial cooling. The population of V. diluvianus displays variability correlated with climatic changes. The population from the Taxus Zone is characterized by a higher content of mature forms compared to the earlier population from the Picea-Alnus Zone. Because the mature individuals are slimmer than the juvenile forms, their last whorl is relatively lower and the aperture relatively smaller. In populations from the Taxus Zone the mean slimness of the shell therefore increases, followed by a decrease in the mean relative height of the last whorl and the mean relative aperture height. 相似文献
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A rich Kimmeridgian ammonite fauna is described from the Janusfjellet Subgroup at Holmgardfjellet, Agardhbukta, East Spitsbergen. The fauna collected from a narrow stratigraphic interval represents a single ammonite assemblage showing a wide but continuous range of variability, with end-forms strongly resembling Amoeboceras (Hoplocardioceras) decipiens Spath and A. (Amoebites) elegans Spath, respectively. Accepting a horizontal classification in ammonite taxonomy, the assemblage may easily be placed into a single species for which the name Amoeboceras (Amoebites) uralense Mesezhnikov, 1973, is available, as this form corresponds to the intermediate and the most common morphotype. The fauna with A. uralense is possibly directly below that with A. elegans and A. decipiens , but above that with A. kochi . Close phyletic relations are suggested between the A. elegans - A. uralense group (traditionally placed in the subgenus Amoebites) and the subgenera Hoplocardioceras (type species A. decipiens) , and Euprionoceras (type species A. kochi). 相似文献
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KRZYSZTOF BIŃKA JERZY NITYCHORUK JAN DZIERŻEK 《Boreas: An International Journal of Quaternary Research》2011,40(2):342-350
Bińka, K., Nitychoruk, J. & Dzier?ek, J. 2010: Climate stability during the Eemian – new pollen evidence from the Nidzica site, northern Poland. Boreas, 10.1111/j.1502‐3885.2010.00179.x. ISSN 0300‐9483 Interglacial sediments at Nidzica, northern Poland were investigated by means of pollen and isotope analysis. These deposits accumulated in an extensive basin through most of the Eemian and Early Weichselian, practically without stratigraphic gaps. Continuous subsidence of the basin floor has resulted in the accumulation of a great thickness of lacustrine sediments, consisting mostly of calcareous gyttja. The course of pollen and isotope curves in the interglacial interval does not indicate the abrupt climatic shifts reported from some other continental climatic archives. Particularly important has been the reconstruction of the final stages of the Eemian, a potential analogue for future climatic change in the late Holocene. At Nidzica, this period is registered as a gradual modification of forest composition, devoid of any pulsations in which temperate forest is followed by terminal, boreal pine–birch communities. 相似文献
9.
KRZYSZTOF BRODZIKOWSKI ANTONIUS J. VAN LOON 《Boreas: An International Journal of Quaternary Research》1985,14(2):175-188
Glaciated areas often show strongly deformed deposits which are difficult to correlate. It may he possible, however, to analyse the relative frequency and nature of sedimentary and glacitectonic deformations in isolated exposures. Their comparison may provide a differentiation of stratigraphic and structural units with identical properties. Such an analysis has been carried out in a small Polish area (the Jaroszów Zone) where the Quaternary and part of the Tertiary sediments show a chaotic character, due to a variety of deformational processes. Deformations took place syndepositionally, metadepositionally and postdepositionally. It appears that the deformation was more or less continuous, but nevertheless some stages with more intensive deformational activity occurred. This resulted in two levels (called structural floors) that represent intervals in which the main type of deformation changed: the lowermost sedimentary unit is characterized by glacitectonic and glacidynamic structures, the middle unit by largescale load casts and associated structures, whereas the top part shows a high frequency of smallscale syn- and metasedimentary deformations. This analysis enabled the unravelling of the sedimentary and deformational history of the area; a similar approach might be applicable to other Quaternary areas that have been strongly deformed as a result of glaciations. 相似文献
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KNUT KAISER ALEXANDRA HILGERS NORBERT SCHLAAK MICHA&#; JANKOWSKI PETER KÜHN SIXTEN BUSSEMER KRZYSZTOF PRZEGI&#;TKA 《Boreas: An International Journal of Quaternary Research》2009,38(3):591-609
Lateglacial buried soil horizons, which occur widely in sandy aeolian sequences of northern central Europe, were analysed in order to evaluate their regional pedostratigraphical and palaeoenvironmental potential. Data on stratigraphy, sedimentology, pedology, geochronology and palaeobotany from 29 palaeosol-bearing profiles at terrestrial sites are presented. Greyish Ahb and Eb horizons occur, as well as brownish Bwb and BwAhb horizons. They are 5–30 cm thick, showing similar pedological properties except colour, and they frequently bear charcoal typically from pine. Soil classification results in Albic Arenosols (Dystric) and Brunic Arenosols (Dystric) representing palaeosols of the Usselo and Finow types, respectively. Radiocarbon dating of the palaeosols reveals a dominance of Allerød ages followed by Younger Dryas and Preboreal ages. Most luminescence ages on overlying aeolian sands date into the Allerød–Younger Dryas interval. Mapping of all Usselo and Finow soil occurrences ( n =96) in northern central Europe known so far reveals a nearly closed Finow soil province between Usselo soil areas in NW Germany and central Poland, mainly situated in NE Germany. Most Usselo soils compiled contain charcoal, indicating widespread and repeated fires. Recent claims that the Usselo soil represents an event layer from rapid aeolian sedimentation caused by an extraterrestrial impact is rejected. Instead, both Usselo and Finow soils can be assumed to be pedostratigraphical marker horizons in northern central Europe and beyond. 相似文献