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St Martin's church, Angers, is emblematic of the problems raised in pre-12 century history of architecture. In view of the importance of this building, it was necessary to attempt to define its dating and this study particularly focuses on its bell-tower. In addition to the conclusion resulting from the interpretation of written sources and typological criteria positioning the construction of the site at the beginning of the 11 century, not only a significant number of C dates were carried out on charcoals from the masonry structures, but also independent dating by archaeomagnetism and thermoluminescence were performed on bricks from the bell-tower. The whole results from these three different methods agree and indicate the lower level of the bell-tower was likely built in the 9 century, disputing evidence to the theory of construction in the 11 century of the church. Presented here are the detailed results obtained from the thermoluminescence (TL) dating analysis. [ABSTRACT FROM AUTHOR]

One sample from a fluvial terrace of Loir river (France) deposited during isotopic stages 7-8 and two samples from isotopic stage 5 marine sediments of Echizen Coast (Japan) were dated by ESR of quartz grains. Both additive and regenerative techniques were used on Ti-Li and Ti-H centers of quartz. No change of sensitivity of the centers was observed during regeneration which significantly reduced the errors on the equivalent doses. Bleaching experiments indicated that the Ti-Li center is less sensitive to UV(ultra-violet)-A (365-412 nm) than to the full sun spectrum whereas UVA alone is sufficient to reset the bleachable component of the Al-center. This effect could be the origin of the strong overestimation of the ages determined using the Ti-Li center in this study. The comparison of the equivalent doses determined by the two Ti-centers indicated that bleaching before deposition of the fluvial sediment was apparently better than for the marine sample. [ABSTRACT FROM AUTHOR]

The Teutonic Order Castle in Malbork is one of the precious medieval monuments in Europe. Because of the lack of natural rock resources in Pomerania, its walls are built almost exclusively of bricks. The huge volume and rich historical knowledge about the Malbork Castle makes it a marvellous object for TL dating. The parts of well known age can serve for the verification and improvement of dating method. Subsequently, gained in such way knowledge and experience can be applied for discovering the history of the rest of the castle. Here, the preliminary results of investigations which are still in progress, are presented for 5 brick samples. The applied TL dating procedure is described in detail. The very good accuracy of equivalent dose is achieved by the TL single-aliquot regenerative-dose protocol. The effect of wall inhomogeneity connected with the difference between the activity of the brick and mortar is discussed. [ABSTRACT FROM AUTHOR]

For the purpose of both luminescence dosimetry and dating, a new portable mini automated luminescence-measuring system has been developed. The main parts of the new system consist of the stimulation unit, an irradiation unit and the photon detector. The size of the main measuring box is approximately 300×300×300 mm. In particular, to keep the electric power as low as possible, a miniature X-ray (Oxford, Eclipse II reflection target) generator and a metal-packaged photomultiplier tube (PMT) (Hamamatsu photonics, H7421-40) were adopted here. 16 blue LEDs were employed for the stimulation of quartz OSL. The same LED holder can be used for pulsed-OSL (P-OSL) measurements. The weight of the main part of this system was about 15 kg. In order to check the usefulness of the new system, red thermoluminescence (RTL) glow curves were measured to estimate the signal-to-noise ratio (S/N ratio) using a volcanic quartz sample. These results show that the new system improves the S/N ratio in comparison with an existing handmade system. The estimated RTL equivalent (or paleo) dose using quartz extracted from an archaeological roof tile of Shin-Yakushiji temple by means of the SAR protocol was in good agreement with previous measurements. This proves that the new system is suitable for practical use for RTL-measurements either for dosimetry or for dating with a high S/N ratio. [ABSTRACT FROM AUTHOR]

The RTL-phenomena in quartz grains were initially reported and their properties and applications were developed by our group. Although RTL-measurements had the difficulty of overcoming high background counts due to blackbody radiation, the excellent dose linearity and hard-to-bleaching nature of quartz RTL are suitable for accurate retrospective dosimetry and dating of burnt archaeological materials. In his paper, the discovery of RTL-phenomena is described. Subsequently, the construction and features of an automatic luminescence measuring system are mentioned together with innovative methods of decreasing the background level for the RTL measurement. Practical applications to dosimetry and dating are then described from the viewpoints of the preferable nature of RTL in comparison to other luminescence observations. Finally, some recent advances in RTL research are presented based on their emission mechanism correlated with impurity contents. [ABSTRACT FROM AUTHOR]

In this paper, a lithological study taking into account trace metals of the profundal sediments from Slupiañska Bay in Wigry Lake is presented. A profile 5.26 m long has sandy muds at the bottom and moving upwards layers of calcareous gyttja, lacustrine chalk, and again calcareous gyttja are present. The profile is continuous, typical for the sediments of NE Poland formed from Aller&3x00F8;de to recent time. The results of the lithological analysis were correlated with results of high-resolution seismic survey. The results together with radiocarbon dating are part of interdisciplinary complex re- search comprising paleobiological study of pollen, Cladocera, diatom successions and human activity, which will be published in successive papers. [ABSTRACT FROM AUTHOR]

Distinctly diverse results of TL dating are obtained for the deposits with similar lithofacial features but filling morphologically differentiated karst palaeoforms (dolines, pipes, pockets). The infillings of dolines and pipes are mostly of the Saalian age. Based on sedimentological analysis, their formation conditions are related to sub- or/and terminoglacial environment. The age obtained for all infillings of pockets is underestimated in comparison with lithostratigraphic data. A close genetic relationship between these forms and periglacial conditions seems to indicate that the reduction of TL signal is mostly influenced by the disintegration of grains resulted from the repeated freezing and thawing of glaciogenic deposits. A considerable influence of frost weathering on the decrease of thermoluminescence intensity of mineral grains is indirectly confirmed by the results of experimental investigations consisting in the repeated TL measurements of pockets' infillings after successive freeze-thaw cycles. [ABSTRACT FROM AUTHOR]

A newly acquired mass spectrometer MI 1201 by the Mass Spectrometry Laboratory will be adapted to determine rhenium and osmium isotope concentrations using negative thermal ionization mass spectrometry (NTIMS). We describe the principle of the Re-Os dating technique and the thermal ionization phenomena which lead to high precision isotope analysis on NTIMS. [ABSTRACT FROM AUTHOR]

Loesses cover a large area in SE Poland so their exploration is an important part of the palaeogeographical studies on Pleistocene. The research involves stratigraphic problems. At present, luminescence dating provides the greatest number of chronostratigraphic data concerning loesses. In this work we report TL ages of loesses from the last two glacial cycles in SE Poland, obtained in the TL Laboratory of the Department of Physical Geography and Palaeogeography, Maria Curie-Sklodowska University in Lublin after 1993. Samples for TL dating were collected in 11 bess profiles (2-9 samples in each site) in order to obtain additional information for stratigraphic interpretations deduced from paleopedobogical, lithological, structural, and other data. Basing on the comparison of 54 TL ages, we can determine age intervals, in which the dating results of similar values assemble, and then get general information about the periods of intensified Aeolian accumulation related to defined stratigraphic units. The TL ages of all samples were obtained using the total-bleach method (TB) for the determination of the equivalent dose. [ABSTRACT FROM AUTHOR]

This study presents the results of radiometric K-Ar measurements on separated amphiboles from the andesite of the Dubie complex dyke. The data obtained cover the period of (291.3 ± 6.4) Ma, which corresponds to Carboniferous-Permian transition. The age is contemporaneous to the rhyodacitic and basaltoid volcanism of the Krakow region. [ABSTRACT FROM AUTHOR]

The author collected 26 samples from six loess profiles located in Poland and Ukraine and 16 samples from three galcigenic profiles in Lithuania. TL and OSL dates were obtained for the samples. The TL dates were calculated in the Gdañsk University laboratory and the OSL dates were obtained by the Institute of Physics Laboratory at the Silesian Technical University. The dating results were referred to the OSL = f(TL) chart. In respect of luminescent dating results, the Upper Vistulian bess shows a high similarity of IL and OSL dates. It means that loess formation took place in conditions conductive to ensure that solar radiation the grains were exposed to reduce the energy accumulated in them. The TL dates of Middle and Upper Vistulian bess are slightly older than the OSL dates. The largest discrepancies were found in soil sample dates. The analysis of glacigenic profile dates is not unambiguous. The fact that the TL dates are older than the OSL dates may mean that during deposition the conditions were not sufficiently conductive to reduce the energy stored earlier in the grains examined with the IL method. This time could have been sufficient to reduce the energy examined with the OSL method. [ABSTRACT FROM AUTHOR]

In the Outer Carpathians in Bamasiówka radiolarian shale formation, there is an intercalation underlied by bentonite. There were found very rare elements and minerals in this intercalation. It was recognized that this horizon has been filled with products of a big object collision with Earth. The age of the manganese-iron intercalation was determined by potassium-argon (K-Ar) dating of illites to be (89.3±1.2) Ma. Similar age, (85.2±0.6) Ma, was found for the post-impact glass from the Boltysh crater in Ukraine. It was concluded that the formation of this intercalation was synchronous with the Boltysh crater formation at the Cenomanian/Turonian boundary. The research for the K-Ar age of the crater creation in Logoisk (Belarus) established its formation to (124.2±1.2) Ma ago. [ABSTRACT FROM AUTHOR]

The Strzegom-Sobótka Variscan Massif (Fore-Sudetic Block, NE Bohemian Massif) consists of various post-kinematic Variscan granitoids emplaced into Palaeozoic low grade metamorphic rocks. Biotite from five samples representing the homblende-biotite monzogranite, biotite monzogranite and biotite granodiorite has been dated using the K-Ar method for two size-fractions (0.25–0.35 and 0.35–0.5 mm). Finer fractions show more intense chloritization and therefore the results for them were rejected in further discussion. Coarser fractions with higher potassium content were accepted as yielding a maximum estimate approaching the true K-Ar biotite cooling ages. The results are clustered in two groups. The older age group (308.8±4.6 Ma and 305.5±4.3 Ma) comprises results obtained from the biotite granodiorites. They are generally consistent with the zircon crystallization age of 308.4±1.7 Ma reported by Tumiak el al. (2005) and imply rapid cooling of the biotite granodiorite from magmatic temperatures down to the closure temperature of K-Ar isotopic system in biotite. The younger group is defined by 29 1.0±4.4 Ma and 298.7±5.2 Ma ages for the hornblende-biotite monzogranite and 294.2±4.3 Ma age for the biotite monzogranite. In the absence of precise U-Pb or Pb-Pb zircon data further geochronological studies are needed to decipher precisely the cooling history of the monzogranites. [ABSTRACT FROM AUTHOR]

Topmost sediments in two oligotrophic lakes of the High Tatra Mountains were studied in terms of sedimentological characteristics and 210Pb dating. An alpine lake sediments are important source of information on geomorphic process activity in glacial catchments. Two different sediment transfer models are represented. In Morskie Oko lake basin majority of extreme, short lasting geomorphic events triggered on the surrounding slopes are registred in lake sediments (minerogenic laminae), while in Zelene Pleso lake only an effect of prolonged flooding periods are to be seen. The sedimentation rates in both lakes are similar. [ABSTRACT FROM AUTHOR]

The electron spin resonance (ESR) dating was used for freshwater mollusc fossils taken from interglacial deposits at the Gaili&usline;nai and Neravai sites (Butènai/Holsteinian Interglacial), Valakampiai site (Snaigupėlė/Drente-Warthe Interglacial), Jonionys and Netiesos sites (Merkinė/Eemian Interglacial) in Lithuania. Freshwater mollusc samples from the Butėnai/Holsteinian and Merkinė/Eemian Interglacials estimated by ESR yielded different ages: Butėnai - 455.0 to 307.0 ka and Merkinė - 112.5 to 101.5 ka BE Two ESR dates determined for Snaigupėlė Interglacial deposits suggest an average age of about 113.0 ka. This is therefore younger than expected from the palynological data, and it places Snaigupėlė into the interglacial stage, possibly assigned to the MIS Sd that can likely be correlated with the Merkinė/Eemian Interglacial (s.l. Thus, further studies of the deposits and additional ESR dates are needed to make sure that the Snaigupėlė bed is really much younger than expected (about 200 ka) in all recognized sites in different parts of Lithuania. [ABSTRACT FROM AUTHOR]

This paper presents results of absolute dating of alluvial sedimentary series forming a rendzina terrace (higher floodplain) 7-8 m high above the Wislok River channel and a sandy terrace 8-10 m high in the Subcarpathian Pradolina section of the Wislok River valley. The organic mud infilling fossil depressions (palaeochannels?) in the lower part of the rendzina terrace have been dated by the radiocarbon method to more than 38,500 BE The organic series occurring within the sandy terrace yielded three ages >36,000 BE Results of palynological analyses carried out on both sites indicate tundra or forest-tundra environments with water-filled depressions at the time of organic sediments deposition. The top of the 8-10 m high sandy terrace is built of fluvial sands and eolian cover sands with dunes in the upper- most part. Their age has been established by means of the OSL method to 11.2 ±0.9 ka BP. The younger alluvial inset fill is formed of sands and silts with involutions occurring under Holocene muds. They were deposited by a braided river during the Upper Plenivistulian as indicated by two other OSL dates of 22.2±21 ka BP and 14.0± 1.5 ka BE Within the rendzina terrace the youngest series of Vistulian age is built with peats and silts, infilling the wide depression at the foots of sandy hillocks, dated to about 11,800 BP. [ABSTRACT FROM AUTHOR]

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 1051 ±158 Gy. The total-bleach procedure gives considerably different results, because the gradual increase of ED values is recorded up to 2833 ± 896 Gy. TL ages obtained by the TB method were confirmed by palaeomagnetic investigations. [ABSTRACT FROM AUTHOR]

Optically stimulated luminescence (OSL) dating is a quantitative dating method to determine the time of last exposure of sand and silt to (sun) light. However, insufficient resetting of the optically stimulated luminescence signal prior to sediment deposition can result in overestimation of the age of a sample. Therefore detection of so-called poor bleaching is of prime importance in OSL dating. Several methods proposed in the literature for detection of poor bleaching are based on the scatter in equivalent doses obtained by single- aliquot methods. In this paper numerical simulations are used to assess the validity of these methods. The simulations show that scatter in equivalent doses is largely dependent on the number of grains contributing to the luminescence signal of each aliquot, and proportion of poorly-bleached grains in the mixture under study. Thresholds for detection of poor bleaching based on inter-aliquot scatter in equivalent doses are therefore not valid. It is concluded that tight, symmetrical dose distributions obtained on small aliquots (ultimately consisting of a single grain) provide the best indication that the sample is homogeneously bleached. [ABSTRACT FROM AUTHOR]

Radiocarbon dating of mire sediments is useful tool for reconstruction of time scale of wet and dry phases during the Late Glacial and Holocene. The method is applied here to determine palaeohydrological conditions of some Polish regions. On the basis of 14C dating of sediment profiles from North Podlasie Lowland and southern piedmont of Holy Cross Mts., duration of wet (1100-1400, 2100-2600, 4700-5000, 7300-7500, 8000-8400, 8800-9200 and 10,500-10,850 BP) and dry (1700-2200, 2600-2800, 3400-3700, ca 4000 and 4500, 5 100-5700, ca 6400, 6900-7 100, 9200-93 00, ca 10,100 and 10,900 BP) periods is suggested. [ABSTRACT FROM AUTHOR]

In the Lithuania, a palaeomagnetic study of Upper Pleistocene and Late Glacial sediments at five sections has been carried out. The palaeomagnetic study of the varved clays in the Maskauka, Did&zbrave;iasalis and Girininkai sections cover the time interval since 18,000 to 14,000 BP and Man&cbrave;iagirė section covers the time interval since 12,700 to 11,630 BE The palaeomagnetic research of the Merkinė (= Eemian) Interglacial sediments (Netiesos section) cover the time interval since 112.0±25 to 101.5 ± 11.5 ka BE The declination (D), inclination (I) and intensity (J) of the natural remanent magnetization of glaciolacustrine clays (Maskauka, Did&zbrave;asalis and Girininkai sections), as well as Merkinė (=Eemian) Interglacial deposits (Netiesos section) and interstadial sediments (Man&zbrave;iagirė section) were measured. The result of these studies is presented in diagrams. The study reveals that considerable palaeomagnetic information can be obtained from the varved clays. [ABSTRACT FROM AUTHOR]

We dated Holocene and Late Pleistocene mollusc shells collected from coastal sediments of the Caspian, Barents, White and Black Seas by means of both a modified 230Th/U method and the radiocarbon method. Essence of the modification is the removal of the surface (about 1/3 of the weight) of the mollusc shells by nitric acid as it may contain adsorbed detrital 232Th and 230Th. The 230Th/U dates of the inner part of the shells do not require detrital correction with the 232Th activity and well agree with the corresponding reservoir-corrected and calibrated 14C ages of mollusc shells with ages between 1300 and 13,500 BE We tested the modified 230Th/U method on thick-walled and well-preserved mollusc shells from the transgression sediments of the Barentz, White and Black Seas derived during the Mikulino Interglacial (MIS 5e) and the Early Valday Glaciation (MIS 5e). The 230Th/U ages of the inner part of the shells from the Boreal (Eem) transgression sediments of the Barentz and White Seas ranged from 86 to 114 ka and those from the Karangat (Eem) transgression in the Black Sea (Maly Kut and Eltigen sections) from 95 to 115 ka. The new 2230Th/U dates of the shells from the section Eltigen ranged from 100 to 125 ka. [ABSTRACT FROM AUTHOR]

Radiocarbon dating has confirmed the division of the period when the grave complex in Dacharzów was used into two stages, between which there was a distinct gap. In the second stage the graves appeared in cycles, after longer breaks (100 years or more). The cemetery was used from the end of the 17th to the 10th or 10th/9th centuries BC. [ABSTRACT FROM AUTHOR]

A comprehensive geochronological study of a pelagic sediment core altered by hydrothermal processes from the Mid Atlantic Ridge (14.5°N) was carried out using both the and the radiocarbon methods. Complementary foraminiferal tests and oxygen-iso- excess tope determinations were done. The main task was to check whether 230Thexcess dating of such excess diagenetically changed sediments yields reliable absolute ages. For this purpose the vertical distribution of the 238U, 234U, 232Th and 230Th activities along the core was measured. The re- sults proved that it was not disturbed during the aging of the sediment. The long-term hydro- thermal influence had been constant during at least the last 300 ka and did not change the natural 230Thexcess distribution along the core. Hence, 230Thexcess dating yields reliable ages and excess excess allows to calculate sedimentation rate. Between the uppermost and lowermost sublayers of the core we obtained 1.35 ±0.15 cm/ka which agrees with 1.47±0.03 cm/ka derived from conventional 14C ages. These numerical dates, the results of the foraminiferal tests and the δ18O values place the studied sediments to the marine isotope stage 5 (MIS 5). These dates are well correlated with the corresponding sedimentary records from pelagic sediments of the North Atlantic Ocean. [ABSTRACT FROM AUTHOR]