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EN
The results of grain-size analysis of silt deposits from the Kolodiiv site are presented. The seven profiles examined are situated on the terrace of the Sivka River, along a ca. 1 km stretch of its right bank. They comprise Wartanian alluvial sands and gravels over lain by Eemian deposits and Vistulian loess. The average results of aggregate and elementary analyses of selected stratigraphic units, standard grain-size in dices, and some aggregation indices are shown. The results obtained indicate that initial loess material deposited in Kolodiiv was generally not differentiated. Only the youngest palaeosols and the younger loess deposits are enriched in silt, which may suggest lower velocities of wind transporting the material or a change in source material (e.g. from sandy-silty flood sediments to clayey lacustrine sediments). Some changes in source material, transportation force or redeposition of material (e.g. by slope processes) may be deduced from the variable skew ness and flat ness of the grain-size distribution, both aggregate and dispersion.
EN
Twenty-five samples were selected from the Kolodiiv site (7 profiles) for total-bleach thermoluminescence dating. Only about 50% of the TL ages corresponded well to the age expected on the basis of geological interpretation. The rest of the TL dates are over estimates. The discrepancies between the TL age and the geological age of the deposits probably resulted from the presence of an admixture of poorly bleached material, of local origin, transported over a very short distance.
EN
In the Kolodiiv site, occur ring in the valley of the Sivka River (tributary of the Dniester River, Ukraine), Vistulian loess forms a subaerial cover over the Pleistocene terrace II. This terrace consists also of Eemian deposits (palaeosol or organic sediments) under lain by an alluvial succession of Wartanian age. The Kolodiiv 2 profile was studied in detail in order to reconstruct the conditions of loess accumulation, and consequently the climatic-environmental changes, that took place in this region. Eight lithogenetic units were distinguished in the profile: five trans formed by pedogenesis, and three loess beds. The main purpose of this study was to conduct a thorough examination of the units lithology, in particular the grain-size distribution, in order to investigate those loess-forming factors that are influenced by environmental changes (i.e. nature of source material, distance and dynamics of transport, type of deposition and redeposition, and hypergenetic processes). To achieve this, 174 samples were taken at 10 cm spacings along the profile, and the grain-size distributions of the deposits were determined using a laser method with 21 grain-size intervals examined in each sample and statistically analyses. Statistical analysis included: calculation of the main grain-size parameters (according to Folk and Ward's method), grain-size index (Ding etal., 1994) and also two statistical tests (Kolmogorov-Smirnov and Spearman rank correlation) applied in order to find differences or similarities between the grain-size distributions of the lithogenetic units distinguished. Stratigraphic variations in grain-size distribution reflect the division of the deposits into stratigraphic units previously arrived at. Mean values of grain-size index (Igs1) indicate that loess units 2, 4 and 6, differ from the palaeosol units 3, 5 and 7. The grain-size distribution of loess deposits in the Kolodiiv 2 profile varies, with marked dominance of the silt fraction, which indicates that these deposits were trans ported by winds of similar velocities carrying material a short distance from source. As the Aeolian conditions that formed loess deposits in the Kolodiiv 2 profile were generally stable, differences in the grain-size distribution of unit 2 representing the Upper Pleniglacial, suggest three cycles of loess deposition during that interval (with the middle cycle characterized by the most distinct, short-term oscillations in environmental dynamics). The variability in grain-size distribution in units 3-5, which to get her represent the Interplenivistulian (Middle Pleniglacial), reflects the climatic heterogeneity of this period. The palaeosol layers are diamictic. Higher values of grain-size indices show that all Upper Pleistocene palaeosol units of high (interglacial) and low (interstadial) rank are characterized by higher content of fine relative to coarse fraction the lowest mean values of grain-size index occur the soil unit 1, of Holocene age, suggests that this unit is probably a product of very recent, Neoholocene pedogenesis and does not represent the en tire Holocene epoch. The statistical tests results show, great similarity between loess units 2 and 4 (from the middle and upper part of the Pleniglacial), and also between palaeosol units 7 and 8 forming the Horohiv slpalaeosol unit (an Eemian palaeosol and interstadial palaeosols from the Early Vistulian). Further more, the individual nature of loess unit 6, deposited during the Lower Pleniglacial, seems to be associated with the climatic characteristics of this interval.
EN
Many studies conducted in the last few years in Poland indicate that the results of thermo-luminescence dating of loess are reliable and correspond well to their geological ages. They can form the basis for determination of the chronology of changes of palaeoenvironmental conditions. In this paper we report dating results from the Halych IIC profile (Halych Prydnistrov'ja region, Ukraine). Thermoluminescence dating of this profile gives new information about the influence of local condi-tions on the results of TL analysis. As much as 75% of the obtained results are distinctly overestimat-ed, even by several hundred per cent, that is untypical of regional loess profiles. However, in the Halych Prydnistrov'ja region it is the second loess site in which such incompatibility of the expected age and thermoluminescence age is found. This fact indicates how this region is unique among the lo-ess areas of SE Poland and NW Ukraine in respect of the conditions of mineral material transport and deposition. Further investigations are necessary to identify the reasons for regular overestimating of the TL results obtained for loess deposits of the Halych Prydnistrov'ja region.
EN
Samples for the study were collected from, known from the literature, outcrop profiles in Zarzecze, Radymno, Dybawka, Tarnawce and Pikulice-Nehrybka, situated at the Carpathian border, in the vicinity of the Przemyśl town, close to the San River valley (SE Poland). They represent the Vistulian loess-palaeosol sequences. Carbonates occur mainly in the loesses representing OIS 2 and 3. Pollen analysis, carried out for two profiles (Tarnawce, Radymno), throws light on palaeoecological conditions of loess cover formation and transformation.Isotopic analysis of authigenic carbonates was carried out on carbonate cemented bodies dispersed throughout the loess in forms of nodule, rhizolith and rhizocretion and on bioclasts, mainly snail shells, ostracod valves, and sparse globules (probably the internal shells of the naked snails).In the successions studied, the upper Vistulian loess deposited in environment with poor vegetation, contains rhizo- liths and rhizocretions mainly, while in the middle and lower Vistulian loess with well developed soils, gley horizons, and intercalations of subaqueous sediments, remains of snail shells and ostracod valves prevail. The two main forms of carbonates differ markedly in isotopic composition from one another. These differences seem to be more important than those between samples of one form of carbonates along particular sections. That is the result of numerous factors affecting the fractionation of carbon and, in particular, oxygen stable isotopes in the environment of precipitation of authigenic calcite. The isotopic composition of carbonates cementing sediments is controlled mainly by biominerali- zation of organic matter and local climatic parameters which were rather slightly differentiated during the formation of the studied sediments. The d13C values for bioclasts vary in a broader range than for calcitic cements. Usually the snail shell carbonate is more enriched with heavier carbon isotope than that from ostracod valves, resulting from the isotopic equilibrium with precipitation and with surface waters, respectively. Basing on our study we can conclude that fluctuations of isotope composition of authigenic carbonates make it hard to apply as a paleoclimatic indicator. However, the general trend of d18O variation in analysed carbonate fractions from leoss-palaeosol sequences displays some connections with climatic fluctuations.
EN
Yezupil is the first Middle Palaeolithic site discovered in upper part of the Dnister River valley. It is situated in a set of sediments composed of loess and fossil soils lying on alluvia. The results of geological and palaeopedological investigations are presented. They contain lithological and geochemical analyses (main components and trace elements), as well as micromorphological study. Palaeo- and petromagnetic record is presented too. Horohiv pedocomplex developed from the older, Wartanian loess. It is composed of luvisol originated during the Eemian interglacial and chernozem soil - during the Early Vistulian interstadials. An subarctic brown Dubno soil dated to the Interplenivistulian (Middle Vistulian interstadials) separates two parts of the younger loess. Older assemblage of Middle Palaeolithic - Mousterian culture with Levalloisian technique was found in the E horizon of the luvisol and therefore it could be dated to the Eemian interglacial. Younger Middle Palaeolithic - Micoquian-type materials were situated in partially redeposited by solifluction, Early Vistulian chernozem. Scanty and uncharacteristic Upper Palaeolithic assemblage was found in interstadial Dubno palaeosol.
EN
The history of the interlaboratory comparison of TL dating results in Poland started in the 1980s. At that time the Lublin, Warsaw and Silesian laboratories made the first attempts at TL dating of the same loess samples from the Odonów profile. However, the cooperation ceased for many years due to great differences in the obtained TL age estimates. The next interlaboratory comparisons were made in the years 2000-2009 for the loess samples from several Polish (Dybawka, Tarnawce, Dankowice, Biały Kościół) and Ukrainian (Boyanychi, Halych, Velykyj Hlybochok, Yezupil) pro-files. Most of the compared dates, obtained for the loess deposits from the Upper Pleistocene and younger part of the Middle Pleistocene, were consistent. This encouraged us to undertake the Gdańsk-Lublin interlaboratory cooperation in dating of 200-700 ka old loess deposits. Nine samples were tak-en from the Ukrainian profile Mamalyha 2 in 2009 for this purpose. The TL dating results indicate that comparable dates are obtained in two laboratories for loess deposits younger than 300 ka BP. The TL signal obtained in the Gdańsk laboratory for the samples older than 300 ka BP was saturated so such samples should not be dated by the multi-aliquot regeneration method. The results obtained in the Lublin laboratory for these deposits (489-682 ka) confirm that it is possible to date loess deposits older than 500 ka. It probably results from the use of total-bleach method with preheating at 160°C for the equivalent dose determination.
EN
Closed depressions (CDs) are landforms typical for loess areas. 1761 CDs have been inventoried within the Nałęczów Plateau. Large concentrations of CDs: 30–40 forms per km2 occur in areas where thick (more than 10 m) complex of glacigenic sediments (mainly glacial tills) or clay (limniglacial) deposits underlying loess cover. Areas with a low concentration of CDs (fewer than 10 forms per km2) correspond to areas where the loess cover lies on a bedrock (opokas) or on thin sandy-gravelly deposits. The distributions of CDs depends on the conditions of Pleistocene permafrost development and melting, linked with lithological properties of the sediments under loess cover.
EN
Although radiocarbon (14C) dating, uranium-series dating, and optically stimulated lumi-nescence (OSL) dating have been conducted for Upper Palaeolithic sites in the Nihewan Basin, north-ern China, there is room for constructing a detailed chronological framework. In this study, loess sed-iments collected from two Upper Palaeolithic sites, Youfang site and Hutouliang site, were dated us-ing the single-aliquot regenerative-dose (SAR) OSL protocol. OSL measurements for palaeodoses es-timation used fine-grained quartz samples extracted from loess. OSL dating results were obtained as 10-17 ka. These OSL ages were consistent with the related stratigraphy of Palaeolithic sites, archaeo-logical evidence and independent 14C ages.
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EN
Large part of slope sediments (pediment) which are the effect of water induced soil erosion in the loess areas of Polish Uplands, has a close relationship with pre-historical, historical and "present" agricultural activity. The sediments accumulated in different periods are often separated by fossil soils. These soils are correlated with the periods of relinquishment of agricultural land use in a given area. A precise dating of the cycles of fossil soil formation is practically impossible. Therefore it is important to gain a possibility to establish the age of sediments between old fossil soils corresponding with the phases of soil erosion. The organic material in the floor or roof of deposits permitting a 14C dating is very seldom. This is why attempts were made to use the OSL method to date mineral parts of slope sediments. In connection with pedological and sedimentological methods, the OSL method makes it possible to give some information about the age of pre-historical and historical phases of intensive soil erosion. In order to date sediments accumulated during the last 50 years, the method based on measurement of 137Cs isotope in products of soil erosion is used. This paper shows some examples of the application of 14C, OSL and 137Cs methods in some selected research sites. In each case there is a discussion of limitations of the methods used.
EN
This paper focuses on problems connected with equivalent dose (ED) estimation. The ED results obtained by using two methods: regeneration (R) and total-bleach (TB) were compared. To this end, ten loess samples were taken from about 20 m thick Zahvizdja profile (western Ukraine). The obtained results show that the ED values are strongly dependent on the applied technique. When using the regeneration method, the maximum ED value observed is 1051š158 Gy. The total-bleach procedure gives considerably different results, because the gradual increase of ED values is recorded up to 2833š896 Gy. TL ages obtained by the TB method were confirmed by palaeomagnetic investigations.
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EN
This study covers the western part of Poland’s loess Nałęczów Plateau (Kazimierz Dolny, Zbędowice). Mass movements in the Lublin Upland occur during periods of increased precipitation or after a snowy and cold winter. To date, there are no comprehensive studies on active (precipitation, hydrology, vegetation, land use, anthropogenic factors) or passive factors (lithology, slope angle) causing such geohazards in this region. This area’s formations are characterised by high sensitivity to even small changes in moisture content; thus, their geotechnical parameters deteriorate as a result of precipitation or rising groundwater levels. The calculations in this study were chosen to determine the time necessary for ground response to external factors, in addition to determining the impact of these factors on decreases in the factor of safety (FS). Based on calculations in GeoStudio software, the impacts of rainfall totals and duration on slope failure, interpreted as an event where the FS falls below 1.0, were analysed. Accordingly, the threshold rainfall value was determined as the total rainfall at the time of slope failure. The study’s results indicate that loess covers are characterised by average water permeability, relatively high internal friction angles and low cohesion, which, combined with high slope inclination, favour landslide formation even when the slope is only partially saturated. The most unfavourable stability conditions occur at the beginning of spring, indicating that loess stability is significantly affected by snowmelt and precipitation at the beginning of the vegetation season, as well as the occurrence of episodic intense precipitation during the summer.
EN
Successions of loess and other deposits in the Kolodiiv profile, formed during the Eemian Inter glacial and Vistulian Glacial (OIS 5-2), are characterized using the results of heavy mineral analysis. Weathered local carbonate rocks and fluvial deposits (Wartanian Glacial, OIS 6) are used for comparison. It was found that the content of minerals derived from weathered and redeposited Carpathian Flysch increases from bottom to top of the profile. The entire loess succession accumulated under similar lithodynamic conditions and the palaeosols are of similar character.
EN
The Upper Pleistocene loess-palaeosol sequence from the Kolodiiv section (East Carpathian Fore land) has been palaeomagnetically studied. Almost all samples displayed moderate to high positive palaeomagnetic inclinations and declinations en closed between 320° and 40°. How ever, one sample from the fossil soil of the last inter glacial pedocomplex (at 16.6 m pro file depth) was reverse magnetized and there fore can be correlated with the Blake Palaeomagnetic Event. Consequently that palaeosol can be related to (Oxygen Isotope Stage) OIS 5e1. An other sample from the Dubno 1 interstadial palaeosol demonstrated southern declination and significant lowering of inclination (up to 40°). This might be a record of the Laschamp Palaeomagnetic Event or of any Late Pleistocene palaeomagnetic excursion. The magnetic susceptibility and anhysteretic remanent magnetization data reflect the presence of several soils forming during the warm conditions of OIS 5 and the complex nature of the Eemian warming. Two palaeosols that developed between ca.115 ka and 120 ka indicate at least two climatic optima during the Eemian. High values of magnetic susceptibility (up to 300 Ą 10-6 SI units) noted in the middle of the section that contains slump deposits (9.5 m to 11m of depth) suggest that this material was derived from older soils of inter glacial type.
EN
The Kolodiiv section is situated in the central part of the East Carpathian Fore land, on the right bank of the Sivka River, the Carpathian tributary of the Dniester River. This paper summarizes investigations on the loess deposit succession representing the Late Pleistocene, which is subdivided by several interstadial palaeosols and is bracketed by the last interglacial soil/organic deposits and Holocene soil. The Kolodiiv loess-palaeosol sequence provides an excellent high-resolution terrestrial archive of changing climate during OIS 5-2 in the East Carpathian Fore land and forms the basis for a regional pedo- and loess stratigraphy. The stratigraphic scheme was constructed on the basis of palaeosol occurrence, lithological variation in the deposits, and also the results of TL dating and palaeomagnetic in vestigations. The exposure at Kolodiiv contains an archaeological site with Middle Palaeolithic materials. Four types of palaeopedological taxa have been distinguished within the loess deposit at Kolodiiv: an interglacial (Eemian) soil unit, which includes one or two soil-forming episodes; interstadial palaeosols, which include two weaker soil-forming episodes; thin interstadial two-horizonpalaeosols; monogenetic incipient palaeosols. Palaeosols from the first and second group form the Horohiv soil unit correlated with OIS 5. Palaeosols from the third and fourth group occur as different soil types within the Dubno 1 and 2 units, which correspond to OIS 3.
EN
A profile of loess several metres thick with palaeosoils, underlain by calcareous gyttja, out crops in Kolodiiv, Ukraine. Rich and diverse assemblages of molluscs have been found in these deposits. Three types of mollusc communities can be distinguished. The oldest is dominated by freshwater taxa and corresponds to calcareous gyttja of Eemian age. The next two assemblages contain only snails typical of loess. The first of these indicates a cold and dry climate and open environment of arctic steppe type, with rapid accumulation of loess; the second assemblage represents a cold and humid climate and a relatively moist, open environment of tundra type.
EN
The deepening and exploration of the loess-palaeosol section at the foot of the Kopasz Hill at Bodrogkeresztúr have been carried out to expand the existing knowledge of the Carpathian foothill palaeoenvironmental factors and their impact. The study deals with particle size analysis, organic matter and carbonate content. For the presentation of age-depth models, the OSL dates of Bodrogkeresztúr (BKT) and the 14C dates of Bodrogkeresztúr, brickyard 1 were used-, and the diagrams of the Accumulation Rates (AR) derived from them. These were compared with Mass Accumulation Rate (MAR) calculations based on OSL and 14C data from BKT and 14C data from Bodrogkeresztúr, brickyard 1. It became evident that there is a significant difference between the two sections, which may be due to the upland position, the overlap, or the wind tunnel effect. Sedimentological studies revealed coarser grain composition, however, the nearly complete absence of coarser sand fraction is also noticeable in the case of BKT. Also, the entire section is characterized by increased carbonate content due to post-sedimentation processes, recarbonization and leaching. The AR and MAR results show the difference between the suitability of different chronometric methods, indicating that the top of both sections may have been redeposited or eroded.
EN
A new investigation and palaeoenvironmental reconstruction of the loess-palaeosol sequence at Prymorske, SW Ukraine is presented using soil structures, grain size, mineral magnetics, organic carbon and calcium carbonate determinations. Six units of the established Ukraine Quaternary stratigraphical scheme have been identified and analysed above and including the Zavadivka (Holsteinian) marker horizon - Dnieper, Kaidaky, Tiasmyn, Pryluky and Udai. Precipitation and temperature are tentatively reconstructed from soil and sedimentary proxies calibrated by modern analogues. Increased temperatures and precipitation to today are inferred for the red-brown Zavadivka palaeosol. Overlying Zavadivka is the Dnieper loess containing a gley and two chernozems above, possibly representing climatic variations of the Saalian Glaciation. The calcified chernozem Kaidaky is separated by a thin loess from the brown/chestnut Pryluky palaeosol (Eemian) which has features indicating drier conditions to the present. Non-gleyed palaeosols exhibit an enhanced magnetic susceptibility (MS) signal relative to the less weathered loess and highlights the palaeoclimatic potential of the technique. The most well developed palaeosol from this study has the highest MS value (Zavadivka: 80ź10-8 SI units) but this relationship is not always found in the Black Sea region. Previous MS analyses at Prymorske (Nawrocki et al. 1999) report significantly higher values to those of this study. Consequently the MS curve at Prymorske cannot be used with confidence for palaeoenvironmental reconstruction and inter-regional correlation without further investigation and modern analogue study.
EN
The Tarnawce 1 profile, which occurs in the marginal eastern part of the Polish Western Carpathians, contains loesses representing three last glacial cycles. In this paper we report the results of pollen analysis of the Eemian -Early Glacial pedocomplex and of the Lower pleni-Vistulian loesses with an interstadial paleosol. The pollen spectra of 22 samples were determined. The pollen diagram was divided into 7 local pollen assemblage zones (L PAZ). Interglacial climatic optimum was recorded with the Eemian type of vegetation in the T-4 zone. The coldest conditions occurred during the accumulation of loess, which separates the interglacial and interstadial soils.
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