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1
Content available remote Luminescence dating of bricks from the gothic Saint James Church in Toruń
Chruścińska A., Cicha A., Kijek N., Palczewski P., Przegiętka K. R., Sulkowska-Tuszyńska K.
Geochronometria
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2014
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Vol. 41, no. 4
352--360
EN
Saint James Church in Toruń is one of the most important gothic monuments in Poland. The date of the beginning of its construction is known from historical reports but the earlier history of the site remains undiscovered. During the archaeological excavations in years 2010 and 2011 five brick samples were collected for luminescence dating as well as four additional samples from the brick surroundings for the dose rate estimation. The equivalent dose was determined by TL and OSL methods. The TL results differ significantly from the OSL results but the last ones are verified by historical knowledge and radiocarbon dating. Establishing the dose rate from gamma rays needs a special attention because of the complex course of the foundations of the church. The details of the applied approach are presented in the current work. The results obtained indicate that a solid brick construction existed at the site of the presbytery of the Saint James Church before it was build.
2
Content available remote Chronostratigraphy of the Vistulian glaciation on the Kujawy Moraine Plateau (Central Poland) based on lithostratigraphic research and OSL dating
Przegiętka K. R., Chruścińska A., Oczkowski H. L., Molewski P.
Geochronometria
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2008
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Vol. 32
69-77
EN
The subject of the investigations presented here is fixing dilemmatic character (transgressive or recessive) of the Poznań phase of the Vistulian (Weichselian) Glaciation and answering the question about the possibility of lithostratigraphic separation of this phase from the Leszno phase in the region of so called Vistula lob. Here we present the outcomes of the research project carried out on a few tills exposures, which constitute the sedimentological record of the last ice sheet advance on the Kujawy Moraine Plateau. The absolute ages of 17 samples (collected from fluvial deposits uncovered in the geological logs) have been determined by means of the OSL method applying the single aliquots regenerative (SAR) dose protocol. The OSL data are analysed with regard to supposed bleaching conditions at the moment of the last transport and deposition of the material. In conclusion, some remarks on suitability of fluvial sands for OSL dating are made. In most of the investigated sites, there appears to exist only a single till level associated with the main stage of the Vistulian Glaciation. This fact and the results of OSL dating support the hypothesis, that the Poznań phase in Kujawy Moraine Plateau is not a distinct lithostratigraphic unit, but it is a recessive phase of the last glaciation.
3
Content available remote Quartz TL decay due to optical bleaching
Chruścińska A., Przegiętka K. R.
Geochronometria
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2005
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Vol. 24
1-6
EN
In spite of many years of research our knowledge of the traps responsible for the OSL in quartz is not complete. Many papers report the complexity of this signal, determine its components and discuss their usefulness for dating procedures. However the experiments carried out so far do not clearly show the source of carriers which recombine on the luminescence centres emitting the OSL. The trap connected with TL peak around 325 C degrees commonly accepted as easily bleachable, can not be the only one responsible for the many observed OSL components. There should exist TL peaks corresponding to these various OSL components, although it is possible that they are related to very deep traps (that is having large energy of thermal ionisation) which are not detected in the conventional TL measurements carried out up to 500 C degrees. With this in mind detailed analysis was made, using sedimentary quartz, of TL curves measured after successively increased time of bleaching performed during the OSL measurement. TL components were determined using fitting procedures and the effect of bleaching on each of these components is demonstrated.
4
Content available remote Evolution of St. Laurent Mountain near Chełmno based on luminescence dating
Chruścińska A., Lankauf K. R., Luc M., Oczkowski H. L., Przegiętka K. R., Szmańda J. B.
Geochronometria
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2004
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Vol. 23
27-34
EN
Luminescence dating was applied in the studies on the evolution of the St. Laurent Mountain in Kałdus (Lower Vistula Valley, Poland), where archaeological excavation revealed a settlement sequence. The core of the hill is constituted by eolian sands which formed the dune. Above them there is a sequence of deposits consisting of three levels of the silty sand anthropogenic deposits separated by top eolian cover and a layer of the burnt material. Three samples from the eolian base and one from the eolian cover were taken for luminescence analysis. The absolute age was established by a comparison of TL and OSL results. The basement of the St. Laurent Mountain (till and ablation sands) was created by a receding glacier during or short after the last glacial period. It suggests the age limit for the dune not older than 18,000 years. Luminescence dating indicates, that the dune formation was initiated in Pleniglacial just after deglaciation, ca. 16,500 years ago and the top eolian cover was established in Neolithic Age, between 6000 and 8000 years ago. Numerous archaeological findings from the upper part of the mountain and C-14 dates of the burnt material provided data for reconstruction of the last phase of this formation.
5
Content available remote Age of the Vistula River overbank deposits in Toruń
Szmańda J. B., Oczkowski H. L., Przegiętka K. R.
Geochronometria
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2004
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Vol. 23
35-38
EN
The paper presents luminescence dates of the overbank deposits accumulated on the Bazarowa Holm in Toruń. From these results we conclude that the flood deposits accumulation was started in this part of the Vistula river valley between 1000 and 2000 years ago. Deforestation and following increase of the floods. events intensity, which occurred in early Middle Ages, may be the possible reasons for the aggradation phase on the flood plane.
6
Content available remote Chronology of the Vistulian (Weichselian) glacial events in the Lower Vistula region, middle-north Poland
Wysota W., Lankauf K. R., Szmańda J., Chruścińska A., Oczkowski H. L., Przegiętka K. R.
Geochronometria
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2002
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Vol. 21
137-142
EN
Stratigraphy of the Vistulian glacial events in the southern part of the Lower Vistula region in the north Poland is presented. Lithostratigraphic units and TL dating of Vistulian deposits exposing along the Vistula valley between Toruń and the Chełmno Lakeland are described in detail. The obtained results indicate that the Vistulian sequences in the Lower Vistula region were deposited during five palaeogeographical episodes. Three glacial events were distinguished: the first at the beginning of the Middle Vistulian (~65O70 ka) and two younger ones during the Late Vistulian. The Middle and Late Vistulian glacial events were separated by a long ice-free period, between 65 and 30 ka.
7
Content available remote The parameters of traps in K-feldspars and the TL bleaching efficiency
Chruścińska A., Oczkowski H. L., Przegiętka K. R.
Geochronometria
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2001
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Vol. 20
15-20
EN
The fractional glow technique (FGT) applied to the investigation of optically bleached samples of K-feldspars extracted from sediments reveals the coexistence of various groups of traps which are active in the same temperature region over 300 °C. Significant differences between the trap parameters seem to explain the diversity of TL bleaching efficiency for different trap groups.
8
Content available remote Gamma spectrometry in thermoluminescence dating
Oczkowski H. L., Przegiętka K. R., Lankauf K. R., Szmańda J. B.
Geochronometria
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2000
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Vol. 18
57-62
EN
The aim of this paper is to present in detail a method, adopted in our laboratory, for the determination of annual dose. In particular, an analysis is focused on the thermoluminescence dating of eolian sediments from Kępa Kujawska. The advantage of the presented method is that partial matrix doses for alfa, beta and gamma radiation are determined simultaneously from the high resolution gamma spectrometry measurements.
9
Content available remote Dating of the dune in Kępa Kujawska
Oczkowski H. L., Przegiętka K. R., Lankauf K. R., Szmańda J.
Geochronometria
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2000
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Vol. 18
63-68
EN
A dune in Kępa Kujawska is located on the edge of the Toruń Basin. Preliminary studies on the natural thermoluminescence (TL) revealed relative chronology of the dune. The TL profile exposed three stages of the dune formation, which are correlated with three eolian members of dune deposits indicated by sedimentological investigations. The experiments on optical bleaching show that light (sunlight as well as laboratory light) only partially resets natural TL in that material. The high level of residual TL was taken into account in absolute dating of the dune. The TL ages obtained for quartz sand from the upper member are confirmed by radiocarbon dating of soil and burn horizon in proximal part of hte dune. Archaeological remains found in the dune give another evidence for truthfulness of TL dating results. The TL age of the middle member is consistent with conclusions from pollen analysis in the dune and its environments. The formation of this dune was started in the Late Glacial, probably in the Younger Dryas. In this period eolian deposition was stimulated by variable climate conditions. The upper member of the dune is connected with Neolithic and Iron Cultures when anthropogenic activity initiated eolian processes again. During the Atlantic and the Subatlantic periods the dune was rebuilt.
10
Content available remote Beta source calibration for thermoluminescence dating
Oczkowski H. L., Przegiętka K. R.
Geochronometria
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2000
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Vol. 18
53-56
EN
The results of calibration of the dose rate from the beta source, incorporated in the RISO TL/OSL SYSTEM TL-DA-12, are presented. The quartz grains, separated from sediments by a typical procedure applied for thermoluminescence (TL) dating were used as a dosymetric material. The stability of thermoluminescence sensitivity of the material was achieved by the sequence of irradiating and the subsequent annealing of the grains. The calibrated 60Co and 137Cs sources were applied for irradiation with reference gamma doses. The calibration performed in January 1998 confirms the result obtained in 1996 with respect to the decay of activity of the beta source in the meantime.
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