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1

Investigating the filling state of OSL detector traps with the optical sampling method

Mandowska Ewa, Smyka Robert, Mandowski Arkadiusz

Metrology and Measurement Systems

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2022

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Vol. 29, nr 2

361--371

EN

Optically stimulated luminescence (OSL) and thermoluminescence (TL) methods are commonly used in dosimetry of ionizing radiation and dating of archaeological and geological objects. A typical disadvantage of OSL detectors is signal loss over a longer time scale. In this article, we present a method of studying this phenomenon as well as monitoring the state of the detector by means of optical sampling. The method was used to determine the OSL signal loss (fading) characteristics of selected potassium feldspars.

2

Datowanie luminescencyjne. Konstrukcja napromieniacza do weryfikacji efektu mocy dawki

Mandowski Arakdiusz, Mandowska Ewa, Smyka Robert, Majgier Renata, Szufa Katarzyna, Maternicki Krzysztof

Przegląd Elektrotechniczny

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2021

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R. 97, nr 2

24--27

PL

Znając wartość naturalnego tła promieniowania można sposób datować materiały archeologiczne i geologiczne metodami luminescencyjnymi. Szacujemy wiek porównując dawkę naturalną z dawką laboratoryjną. Moce tych dawek różnią się o wiele rzędów wielkości. Nie wiadomo, czy takie porównanie jest uzasadnione. W artykule przedstawiono wyniki teoretyczne i doświadczalne dotyczące efektu mocy dawki oraz koncepcję kontrolowanego elektronicznie napromieniacza do testowania tego efektu.

EN

Knowing the value of the natural radiation background, it is possible to estimate the age of archaeological and geological materials using luminescence methods. We estimate the age by comparing the natural dose with the laboratory one. The dose rates for these two cases doses may fiffer by many orders of magnitude. It is not known whether such a comparison is justified. The article presents theoretical and experimental results concerning the dose rate effect as well as the concept of an electronically controlled irradiator to test this effect.

3

Luminescence dating procedures at the Gliwice Luminescence Dating Laboratory

Moska Piotr, Bluszcz Andrzej, Poręba Grzegorz, Tudyka Konrad, Adamiec Grzegorz, Szymak Agnieszka, Przybyła Aleksandra

Geochronometria

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2021

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Vol. 48, no.1

1--15

EN

The Gliwice Luminescence Laboratory (GLL) is a part of the Institute of Physics – Centre for Science and Education at the Silesian University of Technology, which has gradually evolved since the 1980s. To date, nearly 3500 samples have been dated using luminescence from materials such as ceramics, bricks, and sediments from archaeological and geological sites. Currently, the laboratory is equipped with four luminescence readers and three gamma spectrometers, allowing luminescence dating of approximately 300 samples annually for the needs of research projects. This article focuses on the laboratory procedures used in GLL to obtain luminescence ages. Recent improvements of the GLL's facilities and new equipment, as well as the performance spanning the Laboratory's 30 years of activity, are discussed in terms of obtained results and the involvement in national and international projects.

4

Luminescence characteristics of intraplate-derived olivines

Clark-Balzan Laine, May Venera R., Preusser Frank

Geochronometria

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2021

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Vol. 48, no.1

73--94

EN

Olivine has so far attracted limited attention as a potential luminescence dosimeter. In particular, there is a dearth of information concerning the luminescence properties of geochemically characterised, pure olivine samples. Six well-characterised olivine samples from four intraplate settings are investigated in this study, including emission wavelengths and intensities, growth of signal with absorbed dose, signal stability and recovery of a given dose with a single aliquot regeneration (SAR) protocol. All tested olivines share a low-temperature (90–100°C) UV/blue thermoluminescence (TL) peak, and five of six samples also produce a low-temperature red/yellow emission. Higher temperature TL peaks, which would be thermally stable over geological timescales and could be used for dating, are rarely observed at low doses (c. 46 Gy), but detectable though dim at significantly higher doses (c. 460 Gy). Photostimulated luminescence (PSL) emissions are very dim, but reliably detected emissions are stimulated by blue, yellow and infrared (IR) light. PSL yielded generally successful dose recovery results; however, all tested signals are prone to significant anomalous fading and complex thermal transfer between unbleachable and bleachable traps. These characteristics must be addressed if olivine is to be used as a natural dosimeter for luminescence dating. Given the variety of luminescence responses, it appears that olivine samples in future dating work may need to be individually characterised prior to measurement.

5

Erosion and accumulation phases during the last glacial-interglacial cycle : a case study of the terrace system of the Odra and Osobłoga rivers (southern Poland)

Wójcicki Krzysztof Jan, Pawelec Halina, Malik Ireneusz, Woskowicz-Ślęzak Beata, Moska Piotr

Geological Quarterly

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2020

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Vol. 64, No. 1

104--119

EN

In the Odra and Osobłoga River valleys in the vicinity of the town of Krapkowice, a system of morphological levels is present which is exceptionally extensive compared to other such systems in southern Poland. The extent, origins and chronology of these levels have been the subject of many controversies. In the light of current research, the terraces, which are situated on average 14.5-13, 12-10, 8-6, 6-4 and 3-1 metres above the river level, were formed in the post-Wartanian interval. The main factor driving their development was erosion, which compensated for the effects of large-scale aggradation that had occurred during the anaglacial phase of the Odranian Glaciation (MIS 8) dated to 261 ±15 ka. The impact of climatic conditions on the trends towards fluvial erosion or accumulation was only of secondary importance. According to OSL dating, successive phases of vertical stabilisation of the valley floor occurred ~118.8 ±8.3, 87.7 ±5.7 and 42.0 ±2.0 ka. In the meantime, erosion intensified, which resulted in the formation of lower terrace levels. During the climatic minimum of the Upper Plenivistulian (21.5 ±1.5 ka), under conditions of the delivery of sheet-wash-generated sediment, the aggradation of distal reaches of the Odra River valley was locally marked. During the Late Vistulian and Holocene, erosive tendencies continued, which were reflected by the fact that the surfaces of subsequent inset alluvial fills were situated ever lower. In the light of dating results, it can be concluded that during the colder periods correlated with the Rederstall Stadial (MIS 5b) and with the Hasselo Stadial (MIS 3), a braided river was present in the river valleys examined, which was most probably accompanied by permafrost. During the Eemian Interglacial (MIS 5e), during the Late Vistulian Interstadials and in the Holocene, it was a meandering river.

6

Czytnik OSL z nieliniową funkcją stymulacji optycznej

Mandowska E., Smyka R., Mandowski A., Kieszkowski R., Majgier R.

Elektronika : konstrukcje, technologie, zastosowania

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2018

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Vol. 59, nr 9

12--15

PL

Optycznie stymulowana luminescencja (OSL) jest jedną z podstawowych metod pomiaru dawki promieniowania jonizującego. Mierzona luminescencja jest proporcjonalna do dawki pochłoniętej przez detektor. Czytniki OSL wykorzystują do stymulacji zazwyczaj światło monochromatyczne o stałej intensywności (CW-OSL) lub zmieniające się liniowo (LM-OSL). Nowy czytnik luminescencyjny Helios X1 oferuje szersze możliwości. Stymulacja detektora może być dokonywana za pomocą dwóch długości fali, które mogą być modulowane nieliniowo niezależnie od siebie. Ten sposób stymulacji umożliwia uzyskanie dodatkowych informacji o właściwościach detektora.

EN

Optically stimulated luminescence (OSL) is one of the basic methods for the measurement of the dose of ionizing radiation. The measured luminescence is proportional to the dose absorbed by the detector. Typically, OSL readers use monochrome light with constant intensity (CW-OSL) or linearly modulated light (LM-OSL) for stimulation. The new Helios X1 luminescence reader offers greater possibilities. The detector stimulation can be performed using two wavelengths that can be independently and non-linearly modulated. This method of stimulation provides additional information relating to detector properties.

7

Baltic Sea Holocene evolution based on OSL and radiocarbon dating : evidence from a sediment core from the Arkona Basin (the southwestern Baltic Sea)

Kostecki R., Moskal P.

Oceanological and Hydrobiological Studies

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2017

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Vol. 46, No. 3

294--306

EN

The paper presents the chronology of the Holocene evolution of the Baltic Sea based on the optically stimulated luminescence (OSL) and radiocarbon dating methods applied to a core taken from the Arkona Basin. The dating results were supplemented by grain size and geochemical analysis. The obtained results of OSL and radiocarbon dating enabled the construction of an age-depth model and confirmed the continuous sedimentation since 9900 cal yrs BP. One of the most interesting findings of this study is a clear relationship between the rate of sedimentation and fluctuations in the energy of depositional environment. The analyzed sediment core revealed two sections of different accumulation rates. The bottom section was deposited until 2700 cal yrs BP when the Ancylus Lake and the Littorina Sea were present, characterized by the accumulation rate estimated at around 0.46 mm year-1 and the dynamic sedimentation environment confirmed by grain size parameters. The accumulation rate at the top section deposited during the Post-Littorina Sea stage was estimated at around 1 mm year-1. This stage, characterized by more stable deposition and lower-energy environment conditions, was confirmed by small grain size, symmetric skewness and increasing content of organic matter.

8

Variation of OSL residual doses in terms of coarse and fine grain modern sediments along the Hungarian section of the Danube

Tóth O., Sipos G., Kiss T., Bartyik T.

Geochronometria

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2017

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Vol. 44, no. 1

319--330

EN

Reliable OSL dating of fluvial sediments requires an assessment of incomplete bleaching and consequent residual dose in samples. A well-established way of this is determining the equivalent dose of modern samples from similar sedimentary environments as in the case of palaeo-samples. Meanwhile, relatively low, or close to zero doses are also greatly affected by the thermal transfer phenomenon, which can also lead to a palaeodose overestimation. The present study attempts to quantify both factors in coarse and fine grain modern sediments along the Hungarian section of the Danube River, with the aim of determining their significance when dating both young and palaeo-sediments. Investigations were performed at 30 sites along a 417 km long river section with varying morphological and erosive character. The studied samples were deposited during the record flood of 2013, mobilising and relocating a vast amount of sediment in the system. Tests have shown that thermal transfer can be minimized successfully by choosing preheat temperatures below 200°C, however it remains a significant factor when dating young or modern sediments. Based on equivalent dose measurements, coarse grain samples proved to be relatively well bleached, and residual doses showed only a minor spatial variation. Although in terms of fine grain samples residual doses were obviously much higher, results can enhance the reliability of dates retrieved later from fine grain palaeo-samples. In the meantime, the higher spatial variability of fine grain residual doses may also allow the assessment of the erosive character of different river reaches.

9

Testing the suitability of dim sedimentary quartz from northern Switzerland for OSL burial dose estimation

Trauerstein M., Lowick S. E., Preusser F., Veit H.

Geochronometria

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2017

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Vol. 44, no. 1

66--76

EN

We investigate the suitability of sedimentary quartz associated with former glacial advances in northern Switzerland to provide reliable burial dose estimates using Optically Stimulated Luminescence (OSL). Previous studies on northern alpine quartz show that its signal characteristics can be poor and potentially problematic. We analyse quartz signals of small aliquots, which reveal the presence of a prominent medium or slow component in the initial part of some signals. Nonetheless, rejection of aliquots with unfavourable signal composition does not alter the burial dose estimates, but significantly reduces the data set for De determination. Signal lifetimes from isothermal decay measurements cover a wide range of values, yet the lowest lifetimes are high enough to guarantee a reliable burial dose estimate for samples of < 400 ka. Comparison of small aliquot and single grain burial dose distributions reveals that signal averaging masks partial bleaching in some of the samples. We therefore strongly recommend single grain measurements for samples from this setting and area, in order to exclude age overestimation due to partial bleaching.

10

Some novel features of post-500°C heating blue stimulated OSL emission of fired natural quartz

Koul D. K., Soni A., Datta D.

Geochronometria

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2017

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Vol. 44, no. 1

287--298

EN

In this study, some novel features of the post 500°C blue stimulated optically stimulated luminescence (OSL) of fired geological quartz are reported. Different observations (i) pulse annealing and (ii) impact of bleaching on high temperature TL glow peak suggested 510°C (heating rate of 2°C/s) TL peak trap to be responsible for the observed emission. The dosimetric properties of this emission were seen to make its applicability for dose assessment till kGy range. The signal was seen to be easily bleachable, reaching background value within 100 s with blue light at 125°C. The signal qualified all the tests (i) reproducibility, (ii) negligible recuperation and (iii) accuracy of dose recovery needed for reliable assessment of the radiation dose with modified Single aliquot regenerative (SAR) protocol. Considering the bleachability and high dynamic dose range of this signal, it has the potential to stretch the upper dose limit of dating by one order of magnitude than possible with conventional OSL, corresponding to 325°C TL trap. So, combining all the results, the signal reported here could be very useful for dosimetric applications involving measurement of high radiation dose, like dating.

11

Investigation of the role of the production process on the luminescence of sea salt products

Hunter P. G., Spooner N. A.

Geochronometria

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2017

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Vol. 44, no. 1

121--128

EN

Luminescence dosimetry assumes samples of a given material with diverse provenances behave in a predictable manner, allowing a standardised testing protocol, such as SAR for quartz, to be employed. This article demonstrates that distinct salt products derived from a single manufacturer’s feedstock retain comparable luminescence behaviour. This is the basis of a standardised test protocol: uniting testing procedures which have been shown to be individually applicable. Generalization across samples from different manufacturers and processes is currently under investigation.Luminescent evaluation of five samples produced by Cheetham & Co. gave useful intensities for all emission bands (590 nm, 420 nm and 360 nm TL and blue stimulated OSL), with the spectral and intensity balance of emissions generally similar for each sample. 590 nm emission sensitization was noted after preheating samples to 135°C and 300°C for five minutes. But, the 360 nm TL emission from feedstock salt was a factor of five greater than the same signal from the other processed samples despite the OSL intensity being similar to the other samples.Spectrum variation between aliquots as measured by the 3D TL spectrometer was also investigated and found to be minimal for both the first and second TL glow cycles.

12

Application of different protocols and age-models in OSL dating of earthen mortars

Panzeri L., Cantù M., Martini M., Sibilia E.

Geochronometria

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2017

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Vol. 44, no. 1

341--351

EN

In this study, OSL dating was applied to earthen mortars, consisting in a quartz-rich aggregate dispersed in silty-clayey matrix. The samples were taken from two independently dated structures in Cremona, Northern Italy (Palazzo Raimondi, 1495–1499 AD and Palazzo Soldi, 1770–1790 AD). The evaluation of the equivalent dose (De) was attempted with both the multigrain and the single grain protocols using the 150–250 μm quartz fraction. The reliability and effectiveness of the various statistical methods in identifying the well-bleached samples were tested. The use of the multi-grain technique gave unreliable results, due to the high amount of poorly bleached grains. With the single-grain technique, more promising results were obtained: in particular, the un-log MAM3 and IEU models allowed an accurate evaluation of the mortar expected age in most cases, even if the precision is still relatively low.

13

Influence of in Situ Temperature on the Sensitization of Quartz: a Simulation Study

Koul D. K., Patil P. G.

Geochronometria

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2015

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Vol. 42, no.1

28--40

EN

The influence of ambient geological and burial temperatures, prevailing in nature, on the charge population of the defect centers and, eventually, the sensitivity of the luminescence emission of quartz was simulated using empirical model. Various permutation and combination of these temperatures were incorporated so as to observe, both, the collective and independent impact of these two temperatures on the charge kinetics. The results of seem to demonstrate the role of the ambient temperature in the sensitization of quartz mineral.

14

Determination of Slip-Rate by Optical Dating of Lake Bed Sediments from the Dasht-E-Bayaz Fault, Ne Iran

Fattahi M., Walker R., Khatib M. M., Zarrinkoub M., Talebian M.

Geochronometria

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2015

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Vol. 42, no.1

148--157

EN

The Dasht-e-Bayaz left-lateral strike-slip fault in northeastern Iran ruptured in two destructive earthquakes in 1968 and 1979. The western half of the Dasht-e-Bayaz fault cuts across the dry lake-bed in the Nimbluk valley and has no measurable relief except for at a few localised jogs in the fault trace. We provide the first quantitative constraint on the slip-rate of the Dasht-e-Bayaz fault averaged over the Holocene. The western part of the fault cuts across the Nimbluk valley; the flat surface of which is composed of lake-bed sediments. Small streams cut into the surface of the lake-beds are displaced across the fault by 26 ± 2 m. Two OSL samples of the lake-bed sediments are successfully dated at 8.6 ± 0.6 and 8.5 ± 1.0 ka, from which we calculate a minimum slip-rate of 2.6 mm/yr. This minimum slip rate remains constant with the previously proposed Holocene slip rate of 2.5 mm/yr and within the range of the Holocene slip rate of 2.4 ± 0.3 mm/yr estimated before on the central section of the Doruneh fault.

15

OSL and TL characteristics of fine grain quartz from Mongolian prehistoric pottery used for dating

Solongo S., Richter D., Begzjav T., Hublin J.-J.

Geochronometria

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2014

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Vol. 41, no. 1

15--23

EN

The OSL, post-IR OSL and pulsed post-IR OSL applied to polymineral grains and calcu-lated by fitting to the data the contributions from fast, medium and slow components revealed that the polymineral samples under study are dominated by the medium component. An increase in De’s with increasing integration intervals was observed, which is considered as an indication of increasing me-dium and decayed fast component; and the equivalent doses obtained using different components or minerals reflect also the shape of the dose distributions. The identified fast component in polymineral sample has photoionization cross section of 1.2±0.02 × 10-17 cm2. The present study shows the use-fulness of the application of different luminescence techniques combined with fitting procedures as a check which should be adopted in dating protocols. Based on luminescence ages obtained on poly-mineral grains from prehistoric pottery samples from the Boroo settlement, Mongolia, which are in agreement with independent age control by 14C on charcoal material, it is argued that the manufactur-ing of Xiongnu – pottery at this site lasted until ca. 130±75 AD.

16

Optical dating and sedimentary record from the terrace depositional profile of the Warta River (Central Poland)

Dzieduszyńska D., Petera-Zganiacz J., Twardy J., Kittel P., Moska P., Adamiec G.

Geochronometria

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2014

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Vol. 41, no. 4

361--368

EN

Results of OSL dating and sedimentary studies from the profile of the low alluvial terrace of the middle Warta River are presented. The samples were dated using the single-aliquot regenera-tive method. Dating was used to establish a timing of the Weichselian Late Glacial events in the river valley environment. Stable conditions on the floodplain are expressed by the deposition of organic-rich series radiocarbon dated at 12 900-12 600 cal BP and 11 600-10 770 cal BP. Samples for OSL dating were collected from the mineral material deposited during the intensification of flood events during the Weichselian decline. The results obtained for the alluvia range from 12.78 ± 0.62 ka b2k to 14.33 ± 0.74 ka b2k. Sedimentological criteria allowed to distinguish between particular flood events. Overestimation of OSL ages is probably a result of rapidity of environmental changes in that time.

17

Surface dating by luminescence: an overview

Liritzis I.

Geochronometria

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2011

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Vol. 38, no. 3

292-302

EN

Daylight radiation resets luminescence ‘clock’ to zero on rock surfaces, but transmission depends on the transparency of the rock. On burial, surfaces are no longer exposed to daylight and ac-cumulation of trapped electrons takes place till the excavation. This reduction of luminescence as a function of depth fulfils the prerequisite criterion of daylight bleaching. Thus rock artefacts and mon-uments follow similar bleaching rationale as those for sediments. In limestone and marble, daylight can reach depths of 0.5-1 mm and up to 16 mm respectively, while for other igneous rocks e.g. quartz in granites, partial bleaching occurs up to 5mm depth under several hours of daylight exposures and almost complete beaching is achieved in the first 1 mm within about 1 min daylight exposure. The ‘quartz technique’ for limestone monuments containing traces of quartz enables their dating with Op-tically Stimulated Luminescence (OSL) techniques. The surface luminescence (thermoluminescence, TL or OSL) dating has been developed and further refined on various aspects of equivalent dose de-termination, complex radiation geometry, incomplete bleaching etc. A historical review of the devel-opment including important applications, along with some methodological aspects are discussed.

18

Preliminary results towards the equivalence of transformed continuous-wave optically stimulated luminescence (CW-OSL) and linearly-modulated LM-OSL) signals in quartz

Kitis G., Polymeris G. S., Kiyak N. G., Pagonis V.

Geochronometria

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2011

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Vol. 38, no. 3

209-216

EN

The present paper presents a comparative experimental study of two commonly measured Optically Stimulated Luminescence (OSL) signals in quartz. The experimental study measures both the continuous wave OSL (CW-OSL) and the linearly modulated (LM-OSL) signals from the same quartz sample for a range of stimulation temperatures between 180 and 280°C, while the former is transformed to pseudo LM-OSL (ps LM-OSL). A computerized deconvolution curve analysis of the LM-OSL and ps LM-OSL signals was carried out, and the contributions of several OSL components to the initial OSL signal (0.1 s) were shown to be independent of the stimulation temperature used during the measurement. It was also found that the composite OSL (0.1 s) signal consists mainly of the first two OSL components present in the OSL curves. The equivalence of the ps LM-OSL (trans-formed CW-OSL) and of LM-OSL measurements was also examined by an appropriate choice of the experimental stimulation times, and of the stimulation power of the blue LEDs used during the meas-urement.

19

Investigating the resetting of OSL signals in rock surfaces

Sohbati R., Murray A. S., Jain M., Buylaert J.-P., Thomsen K. J.

Geochronometria

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2011

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Vol. 38, no. 3

249-258

EN

There are many examples of buried rock surfaces whose age is of interest to geologists and archaeologists. Luminescence dating is a potential method which can be applied to dating such surfaces; as part of a research project which aims to develop such an approach, the degree of resetting of OSL signals in grains and slices from five different cobbles/boulders collected from a modern beach is investigated. All the rock surfaces are presumed to have been exposed to daylight for a prolonged period of time (weeks to years). Feldspar was identified as the preferred dosimeter because quartz extracts were insensitive. Dose recovery tests using solar simulator and IR diodes on both K-feldspar grains and solid slices taken from the inner parts of the rocks are discussed. Preheat plateau results using surface grains and slices show that significant thermal transfer in naturally bleached samples can be avoided by keeping preheat temperatures low. Equivalent doses from surface K-feldspar grains were highly scattered and much larger than expected (0.02 Gy to >100 Gy), while solid surface slices gave more reproducible small doses (mean = 0.17š0.02 Gy, n = 32). Neither crushing nor partial bleaching were found to be responsible for the large scattered doses from grains, nor did the inevitable contribution from Na-feldspar to the signal from solid slices explain the improved reproducibility in the slices. By modelling the increase of luminescence signal with distance into the rock surface, attenuation factors were derived for two samples. These indicate that, for instance, bleaching at a depth of 2 mm into these samples occurs at about ~28% of the rate at the surface. We conclude that it should be possible to derive meaningful burial doses of >1 Gy from such cobbles; younger samples would probably require a correction for incomplete bleaching.

20

Geoarchaeological studies on Roman time harbour sediments in cologne - comparison of different OSL dating techniques

Lauer T., Bonn R., Frechen M., Fuchs M. C., Trier M., Tsukamoto S.

Geochronometria

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2011

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Vol. 38, no. 4

341-349

EN

Due to the construction of a new North-South subway in Cologne, Roman time harbour sediments were exposed and were sampled for luminescence dating. A very good independent age control was given by the precise knowledge of the chronology of Roman activity and by radiocarbon ages of charcoal samples. Hence, different methodological approaches within luminescence dating were applied for Holocene heterogeneously bleached fluvial samples and were compared to the known ages. For one sample, optically stimulated luminescence (OSL) dating was applied to coarse-grained quartz using a single aliquot regenerative-dose (SAR) protocol. After De-measurements, different statistical approaches were tested (i.e. arithmetic mean, median, minimum age model, finite mixture model, leading edge method and the Fuchs and Lang approach). It is demonstrated that the Fuchs and Lang approach along with the leading edge method yielded the best matching OSL ages with respect to the known ages. For the other sample which showed feldspar contamination within the quartz signal, the post-IR blue stimulated luminescence (double SAR protocol) was measured in three different ways to calculate the De-value: with continuous wave (CW) stimulation with an IR-bleach at 50°C and at 225°C for 100 s prior to the OSL, and pulsed OSL (POSL). It was demonstrated that the IR-stimulation at 225°C has very good potential to remove the feldspar signal contribution as well as pulsed OSL, but the former might deplete parts of the quartz OSL signal.