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1

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%).

2

Early Holocene alluvia in the lower Wisłok River valley and their chronostratigraphy in the light of radiocarbon datings and palynological analysis

Superson S., Gębica P., Michczyński A., Kołaczek P., Szczepanek K.

Geochronometria

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2017

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Vol. 44, no. 1

216--225

EN

The paper presents the results of the latest radiocarbon dating and the palynological analyses of organic sediments found in the alluvia of the Wisłok River valley between the towns of Łańcut and Przeworsk. The study conducted in the gravel pit made possible the dating of several alluvial fills of the 7–8 m high Holocene terrace and the 5–6 m high floodplain. The oldest channel alluvia and palaeochannel sediments of the 7–8 m high terrace were dated at 10 100–9300 BP (11 960–10 500 cal BP). According to the anthracological analysis the top cover of clay overbank alluvia, which bears charcoal fragments, was deposited in the Subboreal and/or the Subatlantic Phases. In the sequence of the 5–6 m high floodplain, the bottom fills of palaeochannels, dated at 10 195–9885 cal BP (probability level: 68.2%; GdS-3233: 8900 ± 95 BP ) and 11 095–10 755 cal BP (probability level: 68.2%; GdS-3228: 9575 ± 95 BP), were truncated by erosion and covered by alluvia of palaeomeanders, which were active in the 19th century. Preservation of the erosional bench of the Early Holocene organic sediments indicates the predomination of lateral migration of the river channel during the last 200 years and the formation of wide erosional floodplain that has been aggraded with recent flood alluvia. In the 20th century the floodplain aggradation was simultaneous with the deepening of the Wisłok riverbed.

3

Record of the meso- and neoholocene palaeoenvironmental changes in the Jesionowa landslide peat bog (Beskid Sądecki MTS. Polish Outer Carpathians)

Margielewski W., Kołaczek P., Michczyński A., Obidowicz A., Pazdur A.

Geochronometria

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2011

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Vol. 38, no. 2

138-154

EN

The paper presents an analysis of depositional sequences of landslide peat bog situated in the depressions developed within the landslide landforms Jesionowa in the Beskid Sądecki Mts. (Outer Carpathians). The peat bog, with depositional sequence 2.80 m long, started to form at the begin-ning of the Atlantic Phase ca. 6390-5910 cal BC. Palynological and lithological analyses as well as several (14) radiocarbon age determinations of different horizons in the sediments enabled the recon-struction of palaeoenvironmental changes during the Meso-and Neoholocene. The increase in climate humidity at the beginning of the Subboreal and Subatlantic Phases was observed as delivery of minerogenic material to the peat bog basin and formation of a mineral horizon and an illuvial level within the peat. The particularly intensive delivery of allochthonous material to the peat bog took place at the beginning of the Subboreal Phase and was the result of both significant humid climate and increased human impact (colonization of the Funnel Beaker Culture) in the landslide area. Similar influence of younger colonisations of landslide area (Przeworsk Culture and, later, Valachian coloni-sation) was also recorded within the deposits of peat bog (illuvial and mineral horizons) in the early Subatlantic Phase. Rejuvenation of the landslide zone and formation of the younger landslide were connected with the increase in climate humidity at the beginning of the Subboreal Phase. The peat bog deposits situated within this younger landslide, which are ca. 1.8 m thick, are significantly con-taminated with mineral material.

4

Records of the Middle - and Late Holocene palaeoenvironmental changes in the Pcim-Sucha landslide peat bogs (Beskid Makowski Mts., Polish Outer Carpathians)

Margielewski W., Michczyński A., Obidowicz A.

Geochronometria

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2010

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Vol. 35

11-23

EN

The paper presents analysis of depositional sequences of two peat bogs situated in the depressions developed within the landslide landforms Pcim Sucha in the Beskid Makowski Mts. (Outer Carpathians). The older peat bog, with depositional sequence 3.75 m long, started to form at the decline of the Boreal Phase ca 7570-7330 cal BC. Palynological and lithological analyses as well as numerous (18) radiocarbon datings of different horizons in the sediment enabled reconstruction of palaeoenvironmental changes of the Middle and Late Holocene. Increase in climate humidity at the beginning of the Atlantic, Subboreal and Subatlantic Phases were observed as deliveries of minerogenic material to the peat bog basin and formation of illuvial and mineral layers within peat. The particularly intensive delivery of allochtonous material to the peat bog took place at the beginning of the Subatlantic Phase and was the result of both significant humid climate and increased human impact (colonization of the Przeworsk Culture) in the landslide area. Rejuvenation of the landslide zone and formation of the second landslide were connected with this period and processes. Deposits of peat bog situated within this younger landslide, which are ca 1.3 m thick, are significantly contaminated with mineral material.

5

Możliwości rekonstrukcji zdarzeń ekstremalnych na podstawie dużych zbiorów dat 14C

Michczyńska D. J., Michczyński A., Pazdur A., Starkel L.

Landform Analysis

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2008

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Vol. 8

53--55

6

The Effect of PDF peaks' height increase during calibration of radiocarbon date sets

Michczyński A., Michczyńska D. J.

Geochronometria

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2006

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Vol. 25

1-4

EN

Large sets of dates are often used to construct frequency distributions to investigate variability of some events, which can follow an environmental change (eg. crystallization of speleothems depends on climatic conditions). Examples of such distributions are probability density functions (PDF) created for radiocarbon dates. In order to reach reliable conclusions concerning environmental changes, we should know how to interpret these distributions. In this study, the authors discuss the problem of a possible correlation between the presence of some high, narrow peaks in the probability density function and the shape of the calibration curve.

7

Statistical analysis of radiocarbon dates as a tool for reconstruction of the environmental changes

Michczyńska D. J., Michczyński A., Pazdur A., Rotnicki K.

Polish Geological Institute Special Papers

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2004

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Vol. 11

109-112

EN

Statistical analysis of large sets of 14C dates may be a source of information on global or regional environmental changes. Since the nineteen seventies, an analysis of the frequency distribution on a time scale of 14C-dated samples has been carried out for several selected geographic regions. This paper presents basics of the applied method and examples of cumulative probability density functions constructed for 14C dates of peat from territory of Poland. It is emphasised that preferential sampling plays an important role in such a type of analysis. The problem of absolute age determination has been discussed, too.

8

The method of combining radiocarbon dates and other information in application to study the chronologies of archaeological sites

Michczyński A., Pazdur A.

Geochronometria

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2003

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Vol. 22

41-46

EN

The Bayesian theorem provides mathematical base for probabilistic calibration of radiocarbon dates, but it is also a base for more sophisticated analysis - combining of probability distribution of calibrated radiocarbon dates with information from other sources – for example stratigraphic information or dates obtained by a method differ than radiocarbon dating. This paper presents three examples of using the method of combining radiocarbon and other information to study the chronologies of archaeological sites. The first example concerns the Inca State chronology and is an attempt to define the time intervals of Inca Imperial Phase and Inca Preimperial Phase accurately. The second refers to the settlement in Wolin and allows to assign the chronology to cultural layers excavated in Trench 6, Site 1 located in central part of settlement and to precise obtained results. The last example concerns South American site - Maucallcta and is a case, when application of the method does not give results because of ambiguity of stratigraphic information.

9

Precision of 14C dating in Gliwice Radiocarbon Laboratory. FIRI programme

Pazdur A., Fogtman M., Michczyński A., Pawlyta J.

Geochronometria

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2003

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Vol. 22

27-40

EN

In this paper the precision and accuracy of radiocarbon dating in Gliwice Radiocarbon Laboratory on the background of intercomparision programs is discussed. Here are briefly presented results of individual comparisons between laboratories from eight countries and three international intercomparison programmes: ISC Programme (1986), TIRI Programme (1994) and FIRI Programme (1999). Moreover the short description of Gliwice Radiocarbon Laboratory is presented. The main stress is laid on the description of FIRI Programme – types of samples included in Programme and methods of calculation of consensus values, but first of all the participation of our Laboratory in the programme is presented: pretreatment procedures of samples, results obtained in Gliwice and statistical analysis of these results. The most important conclusion, which may be drawn from this paper, is that Gliwice Radiocarbon Laboratory dating results are not biased by systematic error.

10

14C Dates of peat for reconstruction of environmental changes in the past

Michczyńska D. J., Michczyński A., Pazdur A., Żurek S.

Geochronometria

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2003

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Vol. 22

47-54

EN

Cumulative Probability Density Functions (CPDF) for sets of 14C dates of peat were constructed for different geographic regions of Poland. On the preliminary stage of our study, CPDF for Southern Poland region seemed to be in good correlation with appropriate distribution for Lowlands and Lake Districts region, but rather in anticorrelation with Baltic Coast region. Similarly, CPDF for Baltic Coast region and Lowlands and Lake Districts region seemed to be in anticorrelation. Authors made Monte Carlo experiment to estimate significance of correlation coefficient value. The amount of dates in analysed sets is too low to draw unequivocal conclusions.

11

Comparison of the radiocarbon dating methods used in the Gliwice Radiocarbon Laboratory

Pazdur A., Michczyński A., Pawlyta J., Spahiu P.

Geochronometria

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2000

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Vol. 18

9-14

EN

In the Gliwice Radiocarbon Laboratory the technique of gas proportional counters (GPC) filled with CO2 has been used since the beginning of the 70ties. In 1994 the Gliwice Radiocarbon Laboratory started the operation of a liquid scintillation spectrometry system (LSC technique) which consists of a Quantulus 1220 spectrometer and two vacuum rigs for benzene production. The work on the calibration of the Quantulus 1220 for the purpose of radiocarbon dating in three different geometries was undertaken. This paper presents characteristic parameters (background and standard counting rates) of facilities working on the basis of the methods above (GPC and LSC), and a comparison of results of radiocarbon dating obtained using other GPC and LSC facilities. Assessment of the analytical accuracy and precision achieved in routine liquid scintillation counting was based on the results of 14C measurements for TIRI intercalibration samples (and other samples), and on the comparison with the results obtained with well established gas proportional counting method performed in the Gliwice Laboratory.