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1

Origin, weathering and paleoclimatic significance of Middle-Late Pleistocene slope covers, Mt. Kenya, Kenya

Mahaney William C., Hancock Ronald G. V.

Studia Quaternaria

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2022

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Vol. 39, Nr 2

51--81

EN

Stacks of the Pleistocene tills and associated airfall/slopewash/colluvial sediment abound on East African Mountains but few localities exist where thick deposits of middle to Late Pleistocene age can be studied to bedrock with topography the main soil-forming agent over <0.8 Ma. Two tills form the main structure of the catena, the oldest buried in the crest, backslope and footslope of the deposit, the youngest forming the crest and upper backslope, with massive colluvial infill forming a still younger sediment mass superposed on older sediment in the lower backslope, footslope and toeslope, the latter all radiocarbon dated to within the last glaciation (Liki on Mt. Kenya; Weichselian in Europe, Wisconsin in North America). The moraine stack, first identified by J.W. Gregory in the late 19th century, as belonging to the 'Older Glaciation' (Illinoian in North America; Teleki on Mt. Kenya), is much older than originally thought with tills and other paraglacial sediment extending to saprolitic bedrock, paleomagnetic assessment and relative weathering indices placing the mass in the Brunhes Chron. These results demonstrate that despite erosion and weathering, paleosols in toposequences near the margins of successive glaciations retain properties allowing reconstruction of environmental changes over long periods of time.

2

A Tree-Ring chronology from Allerød–YD transition from Koźmin (Central Poland)

Krąpiec Marek, Szychowska-Krąpiec Elżbieta, Barniak Joanna, Goslar Tomasz, Kittel Piotr, Michczyńska Danuta J., Michczyński Adam, Piotrowska Natalia, Rakowski Andrzej, Wiktorowski Damian

Geochronometria

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2020

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Vol. 47, no.1

101--111

EN

Subfossil trunks of pine (Pinus sylvestris L.) from the Late Weichselian were discovered in the site Koźmin in the Koło Basin, central Poland (Dzieduszyńska et al., 2014a). Another part of organic sediments with trunks was excavated in the frame of the research project. Altogether 224 samples from Koźmin were analysed dendrochronologically; they represented generally young trees, 40 to 70 years old. Based on the most convergent sequences, the chronology 2KOL_A1 was produced, 210 years in length. With the wiggle-matching method, it was dated to ca. 13065–12855 cal BP. Dendrochronological dating of trunks buried in organic sediments, most of which occurred in situ, revealed that tree deaths occurred successively, over more than 100 years. That could have been due to unfavourable climatic conditions, as well as extreme events, e.g. strong winds.

3

Reconstruction of atmospheric lead and heavy metal pollution in the Otrębowskie Brzegi peatland (S Poland)

Pawełczyk Fatima, Bloom Karolina, Jucha Witold, Michczyński Adam, Okupny Daniel, Sikorski Jarosław, Tomkowiak Julita, Zając Ewelina, Fagel Nathalie

Geological Quarterly

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2019

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Vol. 63, No. 3

568--585

EN

We reconstruct palaeoenvironmental changes since the Late Holocene in the Orava-Nowy Targ Basin, with an emphasis on anthropogenic influence (Walker et al., 2018). This reconstruction employs multiproxy analyses of the Otrębowskie Brzegi poor fen. We combined radiocarbon and 210Pb dating with elemental geochemistry, stable lead isotopes, and palaeobotanical analyses. The core we investigated covers a period from 4200 ± 100 BC to the present, with a peat accumulation rate varying between 0.001 and 0.243 cm y-1. Heavy metal concentrations, Pb isotopic ratios, and a palynological analysis revealed a significant impact of human activities in the past. The highest concentration and accumulation rate of Pb, were found around 1950 AD. The 206Pb/207Pb quotient ranged between 1.168 and 1.223, with average value around 1.198. Most of the interpretation was based on Pb and its stable isotopes; however, other elements were also important indicators of natural and anthropogenic environmental changes. Our results revealed similarities between the geochemical composition of the peatland studied and other peatlands from the Orava-Nowy Targ Basin.

4

Radiocarbon and lead-210 age-depth model and trace elements concentration in the Wolbrom fen (S Poland)

Pawełczyk F., Chróst L., Magiera T., Michczyński A., Sikorski J., Tudyka K., Zając E.

Geochronometria

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2017

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Vol. 44, no. 1

40--48

EN

A one-meter long peat core was taken from the peatland in Wolbrom (Silesian-Cracovian Upland, southern Poland). The analysis of the botanical composition showed that Wolbrom is a fen. Vegetation species such as Carex rostrata and Phragmites australis have been found. An age-depth model was constructed using 12 conventional radiocarbon dates and 13 lead-210 dates from the upper part of the deposit. In this work, the results of radiocarbon dating are presented. According to the model, we can estimate the age of the fen. The oldest part comes from a depth of 1.05 meter and its conventional age is 5940 ± 95 BP (modelled date 5000–4790 BC, 68.2% probability interval). The accumulation rate varies between approximately 0.53 mm·yr–1 and 6.48 mm·yr–1 . The core has been also tested for the presence of trace elements (Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn) using ICP-OES. There are considerable variations in the concentrations of the tested metals – in many cases the concentration starts to rise at about 40 cm and may be connected with the human activity. This depth corresponds to the modelled age intervals 355–300 BC (17.4%) and 205–45 BC (50.7%).

5

Polgár-Bosnyákdomb, a Late Neolithic tell-like settlement on Polgár Island (NE Hungary). Preliminary results of the investigations

Raczky P., Anders A.

Folia Quaternaria

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2016

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nr 84

99--122

EN

In this study, we summarise the preliminary results of thirty years of investigations at the Polgár-Bosnyákdomb site. The significance of the site located on the one-time bank of the Tisza River is that it lies no more than 5 km away from the well-known Polgár-Csőszhalom settlement complex. One of our goals was to investigate the relation between the settlements in the Polgár Island micro-region and to identify the similarities and differences between them. It is quite obvious that with its estimated 70 hectares large extent, Polgár-Csőszhalom was a dominant settlement complex in this landscape during the earlier fifth millennium, while the Bosnyákdomb settlement, represented an entirely different scale with its 8 hectares and had a different role during this period. The AMS dates provide convincing evidence that the two settlements had been occupied simultaneously during one period of their lives. Despite their spatial proximity and chronological contemporaneity, the two settlements had a differing structural layout. Although both had a prominent stratified settlement mound that was separated from the single-layer settlement part by a ditch, the system of the ditches, their structure and, presumably, their social use differed substantially. This would suggest that each community constructed its settlement and architectural structures according to different spatial rules in the different locations of Polgár Island. Despite the spatial differences, we could identify traces of similar community events on the settlement mounds at Bosnyákdomb and Csőszhalom such as the recurring practice of house burning. Despite the smaller excavated areas, we identified wholly different mortuary practices at Bosnyákdomb, diverging fundamentally from the funerary rites practiced at Csőszhalom. The bones of the deceased were secondarily deposited into the ditch of the central mound. The various cultural features discussed in the above indicate that the community responses of the groups settling and living in the Polgár area during the Late Neolithic to the environmental challenges of the land around them were embodied by a set of distinctive cultural behaviours. Nevertheless, certain elements in the colourful diversity of material features and their different levels outline the structure of a micro-regional network with Csőszhalom in its centre in the Upper Tisza region.

6

Comparative 230Th/U and 14C Dating of a Buried Stump Layer (Western Siberia)

Maksimov F., Kuznetsov V., Laukhin V., Kuksa K., Levchenko S., Grigoriev V.

Geochronometria

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2015

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Vol. 42, no.1

139--147

EN

Dating of late Pleistocene sediments remains a challenge in Quaternary chronology, due to the inherent limitations of the 14C and OSL methods. The 230Th/U radioisotope method is theoretically applicable to wood remnants contained within Pleistocene sediments, but few results have been published to date and in some cases, the age data are ambiguous. This paper tests the use of 230Th/U dating of fossil wood remnants dated earlier by radiocarbon method. We analyzed a buried larch trunk from a well-known stump layer in the Lipovka outcrop, located on the Tobol River bank in Western Siberia. The stump layer is preserved in situ. We determined the specific activities of U and Th isotopes in samples of both modern pine and fossil larch and proposed a model for the incorporation and distribution of U and Th in the buried wood during aging. Complications related with the recognition of geochemical closed systems with respect to U did not allow obtaining completely reliable 230Th/U age. Despite this the 230Th/U age obtained for the uppermost heartwood sample and 14C ages of the same larch trunk and other wood and vegetation remnants gave consistent results. These age data in combination with previously obtained pollen data testify the stump layer formation during the late cooling stage of the Karganian time (MIS-3, Middle Valdai).

7

Age constraints and denudation rate of a multistage fault line scarp: an example from Southern Italy

Giano S. I., Schiattarella M.

Geochronometria

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2014

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Vol. 41, no. 3

245--255

EN

The morphological evolution of a carbonate fault line scarp from southern Italy, generated by transpressional faulting and evolved by slope replacement, has been reconstructed. 14C dating of faulted slope deposits (ages included between 18 ka and ∼8 ka BP) have been performed to constrain the Late Pleistocene — Holocene evolution of that scarp. Long-to short-term denudation rates have been also evaluated for the understanding of the mountain front origin. The slope shows well-defined triangular facets combined with the presence of N-S-striking mountainward-dipping fault planes. The envelope of the slope foot appears slightly curved in a planimetric view and shows an E-W-trending offset in its southern part, making such a feature quite different from the recurrent rectilinear fault scarps, often related to normal faulting. Morphostructural analysis showed that: i) the oldest displacement was generated by a fault with a reverse component of movement; ii) the slope represents an inherited feature, only recently exhumed, and developed starting from a high-angle curved surface; iii) the upper Pleistocene — Holocene extensional faulting has only affected the slope foot and associated waste deposits, causing a series of collateral morphological effects, as fluvial cut of preexisting valleys and the genesis of conspicuous mass movements.

8

The first dating of Cave Ice from the Tatra Mountains, Poland and its implication to palaeoclimate reconstructions

Hercman H., Gąsiorowski M., Gradziński M., Kicińska D.

Geochronometria

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2010

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Vol. 36

31-38

EN

Lodowa Cave in Ciemniak, which belongs to the dynamic ice cave type, contains the biggest perennial block of cave-ice in the Tatra Mountains. The ice represents congelation type, since it originates from freezing of water which infiltrates the cave. Two generations of ice have been recognized in this cave. They are divided by the distinct unconformity. The ice building both generations is layered. Two moths which were found in the younger generations were sampled and dated by 14C method yielding 195 ± 30 and 125 ± 30 years. Bearing in mind the position in the section and the fact that the cave ice has waned since the 20s of the last century, the age is 1720-1820 AD and 1660-1790 AD respectively. It proves that the ice was formed during the Little Ice Age. Hence, the erosion boundary which underlies this generation records the degradation of ice before the Little Ice Age most probably during the Medieval Warm Period. The ice volume in the cave was substantially smaller before the Little Ice Age than it is today, despite the clear tendency to melting, which has been recognized since 20s of the last century. The older generation of ice is supposed to have its origins in a cold stage between the Atlantic period and the Medieval Warm Period.

9

Radiocarbon dating of peat profile with metallurgy industry evidence

Tudyka K., Pazdur A.

Geochronometria

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2010

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Vol. 35

3-9

EN

In this work an age model for a peat core from the site near Żyglin, based on 14C is presented. The investigated profile is marked with some possible evidence of early human activity in this region. The earliest metallurgy industry is expected to correspond with charcoal production and the recent increase of metal content in this profile. In this work the Quantulus 1220TM recently purchased was used for 14C dating with liquid scintillation counting (LSC) technique. Therefore results of calibration, tests and verification with use of samples from inter-comparison programs (VIRI, FIRI) are also presented.

10

Chronology of aeolian events recorded in the Karczmiska Dune (Lublin Upland) in the light of lithofacial analysis, 14C and TL dating

Fedorowicz S., Zieliński P.

Geochronometria

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2009

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Vol. 33

9-17

EN

The article studies an average-size parabolic dune located in the northern part of the Chodel Basin, Lublin Upland, Poland within the extensive dune field which covers the contact area of the loess patch slope and the high sandy terrace. Its complex structure and the presence of terrace sand and loess in the floor inspired the authors to conduct detailed lithological studies, as well as TL and 14C dating. As a result, it was possible to determine the mechanism and age of aeolian accumulation cycles in the dune, which contains very good representative evidence of aeolian events in the Lublin Upland.

11

The basis of the study of the age of the Holocene diluvium on loess areas of Polish Highlands

Bluszcz A., Poręba G. J., Śnieszko Z.

Geochronometria

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2007

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Vol. 28

61-66

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.

12

Middle and Upper Weichselian Pleniglacial fluvial erosion and sedimenta- tion phases in Southwestern Poland, and their relationship to Scandinavian ice sheet build-up and retreat

Krzyszkowski D., Kuszell T.

Annales Societatis Geologorum Poloniae

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2007

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Vol. 77, No 1

17-38

EN

The sequence of Weichselian sediments and processes in SW Poland is almost identical to that of central Poland. Generally, three fluvial units occur, comprising silts and sands coarsening upwards to silts, sands and gravels, with aeolian deposits on top. This suggests very uniform processes throughout the palaeogeographic zone. To the south of this zone, there was extensive loess deposition and glacial deposition to the north. Climatic conditions during the Middle and Upper Weichselian Pleniglacial in SW Poland were similar to those in central Poland and northwestern Europe, though the period of 47-43 kyrs BP was slightly milder in SW Poland (shrub tundra, forest-tundra). Climatic conditions during the periods 38-27 kyrs BP and 23-18 kyrs BP were very uniform throughout central Europe, including SW Poland, though there may have been a strong north-south climatic gradient during the former period, as data from the loessic zone indicate at least patches of boreal forest or forest-tundra conditions in SW Poland at that time. It is also possible that there was a Middle Weichselian Pleniglacial interstadial with a lower age boundary at 25,900 ą 700 years BP, characterised by Pinus-Picea forest with no heliophytes. This interstadial represents the last mild period before the advance of the late Weichselian ice sheet into SW Poland. The Weichselian fluvial deposition of SW and central Poland may have been punctuated by at least three major erosional phases, characterised by similar incision depths during the cold stages. Erosion took place, with certainty, at around 75-60 kyrs BP (Lower Pleniglacial) and 27 kyrs BP, very probably at around 23/22 kyrs and possibly at around 40 kyrs BP, and valley aggradation occurred during the milder stages. The Upper Pleniglacial was characterised by valley aggradation, associated with southward ice sheet advance and restricted fluvial outflow. However, the frequent Middle Pleniglacial Weichselian climatic oscillations did not initiate sedimentation and erosion, they controlled only river discharge and type of fluvial sedimentation and aeolian activity. The occurrence of the erosional and aggradational phases were controlled by the changes in ice volume in Scandinavia, ice sheet build-up and retreat, respectively.

13

Some new 14C data to the bronze age in the Slovakia

Görsdorf J., Marková K., Furmánek V.

Geochronometria

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2004

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Vol. 23

79-91

EN

The data come from samples from the archaeological site Včelince (Slovakia). It is a settlement of a multicultural character. The stratigraphy of the layers VII .I assigns chronological sequence: the Hatvan culture, Hatvan-Otomani Horizon of the Hatvan culture, Otomani/Füzesabony culture circle, the Koszider Horizon, Piliny culture. There were applied animal bones for the samples of 14C. They came from the pits as well as from the layers dated by typology, horizontal and vertical stratigraphy. The 14C data confirm the chronological order indicated by the stratigraphical observations in the site. It is the very first 14C measurement in the case of the Hatvan culture in Slovakia. Mesurment of the earliest layer of the Hatvan culture in Včelince provides the data (Bln 5560: 3710š38 BP) which is comparable with the data of the earliest Hatvan culture in Hungary. A part of the teritory of Slovakia can not be excluded from the process of its origin also in spite of the data mentioned above. As the dates are coming from tratigraphically and typologically clearly defined contexts, they are of high importance for the Bronze Age archaeology of the region.

14

Radiocarbon time scale for deposition of holocene calcareous tufa from Poland and India (Orissa)

Pazdur A., Dobrowolski R., Durakiewicz T., Mohanti M., Piotrowska N., Das S.

Geochronometria

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2002

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Vol. 21

85-96

EN

14 C concentration measurements together with carbon and oxygen stable isotope analysis in calcareous tufa give possibilities for reconstruction of time scale and palaeoclimatic conditions of sedimentary processes. Results of isotope examinations of 2 profiles with organic and tufa sediments from Eastern Poland and 8 calcareous tufa sites from Eastern India (Orissa) are given. A systematic error of 14 C conventional age of carbonate fraction of tufa samples as reservoir age (T R ) was estimated. The T R values of different type of tufa sediment are determined by stream water energy. On the basis of known experimental dependence between T R and delta 13 C for tufas deposited in high, average and low energy water, unknown values of T R and corrected 14 C ages (T CCA ) were calculated for samples from India tufa sites. Continuous deposition of organic and carbonate sediments in Polish profiles give the possibility to calculate the approximated T CCA ages on the basis of dependence between T CCA and a sample depth in a profile, and time scale reconstruction of delta 13 C and delta 18 O changes in carbonate fraction of tufa samples during the whole Holocene.

15

14C and TL dating as a method of establishing the origin of kettle-like hollows

Stankowski W.

Geochronometria

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2001

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Vol. 20

103-106

EN

Small circular hollows are very common in the glacial topography of NW Poland. Among them there are also some of meteorite origin. An important example of impact craters exists in the Morasko Meteorite Natural Reserve. The 14 C and Luminescence datings are very helpful in establishing their origin. The last ice sheet retreat and permafrost degradation created kettle-like hollows around the Morasko Hill. Organic infilling started in them between 14,000 - 10,000 BP. The Morasko meteorite shower fell between 5000 - 3500 BP. The craters origins and young hollow bottom organic infillings then started. On the Great Poland Lowland there are other potential areas with forms connected to meteorite falls, the such as Oborniki - Obrzycko area and probably in the so called KKR object fron the south-east part of Great Poland Lowland.

16

Chronology of loess-paleosol sequences at Weinan section, Central China

Jiaqi Liu, Sun Jimin, Chen Rui, Wang Wenyuan

Geologos

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2000

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Vol. 5

165--174

EN

The loess profile at Weinan (34°12’N and 109°31’E), Central China, with good stratigraphic stability and well developed paleosols, was systematically sampled and dated by AMS radiocarbon and TL methods. The preliminary high-resolution time scale of this section has been tuned. Based on this time scale and other climatic proxies such as susceptibility curve and grain-size curve, the author summarizes several for the last 150,000 years age results regarding some important stratigraphic boundaries and established a time scale. According to this time scale, the basal age of S0, located at 143 cm below the top of section, corresponding to the boundary between S0/L1 is 11,980 yr cal BP, this is the age of the beginning of Holocene. The age of the boundary between L1 and S1 is dated 74,220 years B. P. at 854 cm, which shows the ending age of the last interglacial stage is about 74,000 cal BP. Si is highly pedogenised paleosol with dark brown color and 361 cm in thickness. It can be divided into three sub-layers, corresponding to the last interglacial stage, the real S1/L2 boundary is located in 1,180 cm depth and has an age of 128,870 years B. P. It may be correlated with the deep-sea oxygen-isotopic stage 5. The Last Glacial Maximum (LGM) reflected in Weinan loess section by grain size curve and susceptibility curve is from about 20,000 cal BP to 18,000 cal BP. A rapid deposit period from 300 cm to 196 cm lasted a time span from 20,200 cal BP to 19,800 cal BP. The deposit rate of this segment is over 20 times than the average deposit rate of Chinese loess.

17

Sample preparation in the Gliwice Radiocarbon Laboratory for ams 14C dating

Goslar T., Czernik J.

Geochronometria

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2000

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Vol. 18

1-8

EN

The Accelerator Mass Spectrometry has been used in 14C dating for several years. The 14C concentration is measured in graphite target. In the Gliwice Radiocarbon Laboratory a system to produce graphite targets has been built. This system will be used for 14C dating of terrestrial plant and zooplankton macrofossils in lake sediments, and later, in routine 14C dating of small samples.

18

On problems of absolute chronology of the Early Bronze Age in Southwestern Slovakia

Bátora J.

Geochronometria

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2000

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Vol. 19

33-36

EN

This contribution treats new notion about the absolute chronology of Early Bronze Age in southwestern Slovakia. Based on the series of new 14C data from the burial place in Jelšovce, which had been done by J. Görsdorf from Radiocarbon Laboratory of German Archaeological Institute (Deutsches Archälogisches Institut) in Berlin we can date the early phase of Nitra culture to the time period 2200/2150 BC. The time period of transition between Nitra and Únětice cultures 1930-1870 BC and of the classical phase of Únětice culture 1870-1730 BC. The transition between Únětice and Mad'arovce culture was approximately in the time period around 1730 BC.

19

Correlation of 14C and OSL dating of late pleistocene deposits in Lithuania

Gaigalas A.

Geochronometria

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2000

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Vol. 19

7-12

EN

Otically stimulated luminescence (OSL) studies on the 14C dated section of the Middle Nemunas (Middle Vistulian) limno-alluvial deposits of the Jiesia river were made. The most deposits from palaeolake with broad, low-gradient floors of Middle Nemunas interstadial in Central Lithuania are inferred to be more favourable to accurate OSL dating. OSL procedures and sedimentation processes critically affected the accuracy of OSL ages.

20

Chronology of phases of various fluvial activity, of erosion and deposition in the Vistula catchment during late quaternary

Starkel L.

Geochronometria

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2000

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Vol. 19

53-58

EN

The former extensive studies in the Vistula catchment with dozens of profiles well dated by 14C, helped to recognise great diversity of phases with dominance of erosion or aggradation changing in the longitudinal profile. Among them are very distinct synchronous phases with clusterings of extreme events during the Interpleni-glacial and during the Holocene.