The chronology of the Bronze Age in the Carpathian basin is largely based on relative chronologies, i.e. stylistic analysis of ceramic (and other) materials. While the number of radiocarbon dates is generally increasing, certain important sites are still poorly dated. One of the largest necropolises from this period, i.e. Mokrin necropolis, which traditionally belongs to Maros culture, is dated only with 6 radiocarbon dates. Here we synthesize the previous 6 radiocarbon dates with 13 new radiocarbon dates, with two goals in mind: 1) to explore the absolute chronology of the site, specifically to determine its chronological limits; and 2) to test hypotheses about the spatio-temporal organization of the site. Our data show that the chronological limits of the necropolis were most probably between 2073 and 1822 BC. Concerning traditional relative chronologies, none of the previous hypotheses about the internal chronological development of the necropolis is supported by data. Our results suggest that all parts of the necropolis were used relatively simultaneously.

Marine aerosols can enter the terrestrial environment via sea spray which is known to affect the stable isotope fingerprint of coastal samples (plants, animals/humans), including δ13C. However, the impact of sea spray on 14C dating of terrestrial organisms at coastal sites has not been investigated so far. Besides a direct effect, sea spray is accompanied by physiological effects, e.g., due to salinity. In an artificial sea spray experiment in the greenhouse, the effect of sea spray on 14C in plant tissue was investigated. Beach grass was sprayed with mineral salt solutions containing only traces of NaCl or with brackish water from the Schlei inlet or the Baltic Sea. These plants should give a 14C signal close to the modern atmospheric 14CO2 composition. However, three treatment groups showed variable radiocarbon concentrations. Plants sprayed with water from the Schlei inlet, Baltic Sea water, or with a mineral salt solution with very high HCO3– concentration are depleted in 14C content relative to contemporary atmospheric composition. While δ13C reflects physiological effects in the plants, caused either by salinity (NaCl) or HCO3– stress, resulting in decreased discrimination against 13C, the uptake of high amounts of 14C (ca. 53–67%) from DIC (dissolved inorganic carbon) partly masks the underlying physiological reactions, as is visible in the radiocarbon signature of the plant tissues. This preliminary study indicates that sea spray effects on plant tissue could potentially influence faunal tissue 14C composition at coastal sites. Further research is required to better understand the observed reservoir effect.

The Manych Depression is a relatively narrow elongated depression of tectonic origin, connecting the Caspian and Azov-Black Sea basins. The Caspian Sea repeatedly discharged its waters through this depression into the Black Sea and further into the Mediterranean Sea during the Quaternary period. The last discharge occurred in MIS 2 when the Khvalynian transgression waters exceeded the drainage divide between those two basins. The geochronology of the last flow of Caspian waters into the Black Sea was established recently based on 14C dating of Khvalynian shells, carried out mainly by liquid scintillation counting, and the end of this event was dated to 12.5–12.8 ka cal BP. Recently obtained OSL dates for one of the most complete sections of the Khvalynian deposits of the Manych Depression indicate an older time for the end of the flow. This study aimed to clarify the timing of the Khvalynian transgression discharge by examining two sections containing the Khvalynian mollusk fauna in layers that, according to their stratigraphic and geomorphological position, belong to the final phase of the flow of the Caspian waters. Four 14C AMS dates were obtained from single shells of Didacna ebersini and Hypanis plicata, which agree with the OSL dating results. The results indicate that the last overflow of Caspian waters through the Manych Depression had ceased at around 14.5 ka cal BP.

An international consortium of radiocarbon laboratories has established the origin of the Church of St. Margaret of Antioch in Kopčany (Slovakia), because its age was not well known from previous investigations. In total, 13 samples of charcoal, wood, mortar, and plaster were analyzed. The 14C results obtained from the different laboratories, as well as between the different sample types, were in good agreement. Resulting the final 14C calibrated age of the Church, based on dating a single piece of a wooden levelling rod is 774–884 AD (95.4% confidence level), which is in very good agreement with Bayesian modeling result based on dating of wood, charcoal and mortar samples (788–884 AD, 95.4% confidence level). The probability distribution from OxCal calibration shows that 79% of the probability distribution lies in the period before 863 AD, implying that the Church could have been constructed before the arrival of Constantine (St. Cyril) and St. Methodius to Great Moravia. If we take as the terminus post quem the documented date of consecration of the church in Nitrava (828 AD), the Bayesian modeling suggests the age of the Church in the range of 837–884 AD (95.4% confidence level). Although the 14C results have very good precision, the specific plateau shape of the calibration curve in this period caused a wide range of the calibrated age. The Church represents, together with the St. George’s Rotunda in Nitrianska Blatnica, probably the oldest standing purpose-built Christian church in the eastern part of Central Europe.

This study aims to discuss the chronology of the Egyptian 5th dynasty of the Old Kingdom and the tentative date of accession of king Djedkare based on material from his royal necropolis at South Saqqara and non-royal cemetery of Abusir South, Egypt. A series of radiocarbon (14C) dates were established through analysis of archaeological material from several monuments at the necropolis, including the king’s pyramid complex, pyramid complex of his queen, and two elite tombs (Isesiankh and Khuwy). In addition, two samples from non-royal tombs in the Abusir South cemetery, were taken into consideration for further precision during the modeling, associated with king Huni (end 3rd dynasty) and king Niuserre (5th dynasty). The contextualized 14C dates together with re-evaluation of historical evidence on Djedkare’s rule, results in a new model of temporal probability density which can be further refined with any new data from archaeological research. It shows that Djedkare’s reign can be currently modelled between 2503 and 2449 BCE (95.4%), thus slightly older than expected by literature. This presented model provides a more precise chronological frame for the late 5th dynasty period of Egyptian history, which was period of a significant socio-economic transformation.

Radiocarbon (14C) measurements play important roles in dating and tracing applications where the isotopic concentration can differ from 0.1 to 106 pMC (percent modern carbon). A liquid scintillation counter cannot provide enough sensitivity when dealing with low-concentration samples of limited amounts over a reasonable time period. Accelerator mass spectroscopy (AMS) measures low-concentrations well but must first do dilution for high-concentration samples, and suffers from high instrument and maintenance costs. Saturated absorption CAvity Ring-down spectroscopy (SCAR) has now been developed into a practical technique with performances close to AMS but at much lower costs. The dynamic range covers 1–105 pMC, and the measurement uncertainties in the range of 0.4–1 pMC can be achieved within 0.5–2.5 hr of operation time. SCAR measures CO2 gases directly without graphitization in sample preparation. The typical sample consumption is ∼1 mg of carbon mass and the time for sample preparation can be as short as 15 min. Applications of SCAR to Suess-effect evaluation, biogenic-component analysis, ancient- and modern-sample dating, food-fraud detection and medicine-metabolism study have all been demonstrated by employing a close-to-automatic sample preparation system.

Despite the continuous reporting of radiometric chronology of lithic assemblages in the Korean peninsula, systematic evaluation of reliable radiocarbon (14C) dates and discussion on the lithic technological variability have not been adequately presented. This paper attempts to address the issue reviewing the available data on the Early Upper Paleolithic (EUP) of Korea, with a focus on 14C chronology and lithic technology. Also, these recent advances in Paleolithic studies in Korea provide interesting aspects of the transition to Upper Paleolithic (UP) technology in East Asia. The transition to the UP is characterized by two key developments: the emergence of blade technology and tanged points, and the use of quality raw material that had been previously disregarded. Reliable 14C dates published recently indicate that this transition began around 43,000–40,000 cal BP. We propose that the emergence of the UP tradition on the Korean peninsula can be explained by focusing on the mobility, regional exchange networks and population dynamics of hunter-gatherers rather than the continuing resort to the simple unidirectional dispersal.

Accelerator mass spectrometry (AMS) is a worldwide recognized method for radiocarbon (14C) dating. The advantageous aspects of this method include the variety of materials and the small sample size (1 mg of carbon) that can be measured. However, these pose several challenges in the laboratory, such as developing appropriate chemical pretreatment methods. In the summer of 2022, the Radiocarbon and Mass Spectrometry Laboratory in Gliwice, Poland, launched the MICADAS accelerator spectrometer. The report on background and reference materials measurement results for the period from September 2022 to July 2024 is presented in this publication. Quality assurance and quality control processes are extremely important to guarantee the high quality of the results obtained in the laboratory. Hence, our Radiocarbon and Mass Spectrometry Laboratory in Gliwice took part in the Glasgow International Radiocarbon Inter-Comparison (GIRI) program. The radiocarbon ages for wood, bone, humic acid, and barley mash samples were determined and compared with reported values. The resulting data confirmed that our Laboratory is capable of dating samples across a spectrum of materials and ages ranging from contemporary to the limits of the radiocarbon method, achieving precision on par with that of other laboratories.

A limitation in fine-tuned tree-ring radiocarbon (14C) data is normally associated with overall data uncertainty. Tree-ring 14C data variance as a result of sample heterogeneity can be reduced by adopting best practices at the time of sample collection and subsequent preparation and analysis. Variance-reduction of 14C data was achieved by meticulous sample handling during increment core or cross-sectional cuttings, in-laboratory wood reductions, and cellulose fiber homogenization of whole rings. To demonstrate the performance of those procedures to final 14C results, we took advantage of the replicated data from assigned calendar years of two Pantropical post-1950 AD tree-ring 14C reconstructions. Two Cedrela fissilis Vell. trees spaced 22.5 km apart, and two trees of this species together with one Peltogyne paniculata Benth tree spaced 0.2 to 5 km apart were sampled in a tropical dry and moist forest, respectively. Replicate 14C data were then obtained from grouped tree-ring samples from each site. A total of 88% of the replicated 14C results fell into a remarkably consistent precision/accuracy range of 0.3% or less, even though multiple tree species were used as pairs/sets. This finding illustrates how adopting a few simple strategies, in tandem with already established chemical extraction procedures and high-precision 14C analysis, can improve 14C data results of tropical trees.

The application of a tube combustion system (pyrolyzer) for the batch combustion of low carbon content environmental matrices, such as soil and sediment, for determining 14C specific activity is examined. The samples were combusted at 600°C, and the CO2 species produced were trapped in 3N NaOH, precipitated as BaCO3 by adding BaCl2, and subjected to acid-hydrolysis to transfer the CO2 species to the absorber-scintillator mixture for liquid scintillation counting (LSC). The method was validated by analyzing the samples by accelerator mass spectrometry (AMS) method. The minimum detectable activity (MDA) for the method, at 2σ confidence level, was 10 Bq kg–1C (4 pMC) for a counting time of 500 min and 7 Bq kg–1C (3 pMC) for 1000 min. The capability of the method to quantify a small excess of 14C specific activity (a few Bq kg–1C or pMC) in the environment of a nuclear facility, when compared to the ambient natural background level, was demonstrated by analyzing a total of 23 soil and 7 sediment samples from the vicinity of a pressurized heavy water reactor (PHWR) nuclear power plant (NPP) at Kaiga, India. The maximum excess 14C specific activity values recorded for soil and sediment matrices were 37 ± 7 Bq kg–1C and 11 ± 7 Bq kg–1C, respectively, confirming minimal radioecological impact of the operation of the NPP on the environment. The 14C specific activity ratio for the recently fallen leaf litter and the soil underneath at most of the sampling points in the vicinity of the NPP had a mean value of 1.03 with an associated standard deviation of 0.07. Statistical tests confirm that the mean values of the data set of 14C specific activity of leaf litter and underlying soil are not significantly different.

A new model for the interpretation of radiocarbon (14C) dates of Holocene marine shells is presented. For the Netherlands, the size of reservoir effect is difficult to assess, as these shells often lived in an environment of mixed marine- and river waters. Both stable isotopes 13C and 18O of the shell carbonate give insight in the environmental conditions the shells lived in. River water occurs in two main categories, distinguished by 18O: the Rhine which is dominant, and other rivers. This leads to two estuary mixing lines between the North Sea and rivers. The stable isotopes of the shell carbonate are also indicative for additional processes, such as uptake of secondary carbonate from the soil by shells, and exchange of C isotopes between atmosphere and water. Extensions of the main model deal with special cases such as pools of stagnant water and lakes. The model leads to an assessment of the recent 14C activities of the system the shells lived in, called 14aSYS. The measured 14C activities relative to these 14aSYS values determine the 14C age of the shells and include the reservoir effect. This way we circumvent normalizing to δ13C = –25‰, i.e. the terrestrial timescale and the subsequent correction for reservoir effects. The model is applied to a large legacy dataset of marine shells from the Netherlands, obtained during the last 7 decades. It contains 1116 14C dated shells; for the majority of these, the 3 isotopes 13C, 14C and 18O are measured.

We present reservoir effects on shells of species Terebralia palustris and Marcia spp. that were recovered during archaeological excavations at the multi-period site of Tell Abraq, Sharjah Emirate, UAE (This paper was presented at the combined 24th Radiocarbon and 10th Radiocarbon & Archaeology International Conference, Zurich, Switzerland, Sept. 2022.). The site was inhabited during the mid to late Holocene. It is situated in a lagoonal environment with former mangrove forests at the Arabian Gulf coast of southeast Arabia. Due to availability in the immediate proximity, shellfish played an important role for the local subsistence throughout the site’s occupation. Tell Abraq provides a well-defined and stratigraphically controlled archaeological context for investigations on the reservoir effect of the two species chosen. Crucial for the determination of the marine reservoir effect is comparison with contemporaneous terrestrial carbon samples. We discuss the data in a wider context with respect to results obtained at other sites.

AMS radiocarbon ages of organic matter from ice wedges and enclosing peat were determined for the polygonal peatland at the Lorino site on the eastern coast of the Chukchi Peninsula. The study’s goal was to fill a knowledge gap about the dynamics of polygonal peatlands with ice wedges and winter climate conditions during the Holocene in this easternmost region of the Russian Arctic. It has been found that peatland accumulated during the Younger Dryas and early Holocene, mostly between 14 and 9.9 cal ka BP, while ice wedges were dated from 7.7 to 6.6 cal ka BP. Since ice wedges have features of syngenetic growth, the discrepancy in the age of ice wedges and enclosing peatland may result from the significant presence of early and pre-Holocene peat. It is assumed that the older polygonal peatland deeply thawed during the Holocene optimum, and subsequently, when the permafrost aggraded, a new generation of ice wedges was formed. The AMS 14C age (18.1 cal ka BP) of the ice wedge exposed below the peat indicates the presence of a Late Pleistocene generation of ice wedges at the study site. Paleotemperature reconstructions based on the stable isotope composition of ice wedges show that the mean January air temperature during the Northgrippian stage of the Holocene varied from –27 to –23°C, and at the end of the Late Pleistocene, from –32 to –26°C.

This paper presents new radiocarbon dates for two Aboriginal archaeological complexes situated on the cliff-lines of the Murray River in South Australia (SA); at Pooginook Flat and Tanamee. These dates represent the first age estimates for archaeological sites within the Upper Gorge section of the Murray River. The dates ranged from ca. 11 cal ka to the Late Holocene. The research supports previous evidence which has indicated that sites located along the Murray cliffs preserve much of the oldest evidence of Aboriginal peopling along the Murray River corridor in SA. The new dates also allow us to contribute to discussions concerning broader chronological trends in Aboriginal lifeways within the Murray-Darling Basin (MDB). Specifically, the new ages add some insight into the nature and timing of early Aboriginal occupation along the Murray River corridor in SA and further evidence that the LGM acted as a significant inhibitive factor for intensive occupation of this riverscape. The conservation of these significant and informative cliff-top sites remains precarious, however, and there is an imperative to continue to record and sample the extant sites.

The ubiquitous marine radiocarbon reservoir effect (MRE) constrains the construction of reliable chronologies for marine sediments and the further comparison of paleoclimate records. Different reference values were suggested from various archives. However, it remains unclear how climate and MREs interact. Here we studied two pre-bomb corals from the Hainan Island and Xisha Island in the northern South China Sea (SCS), to examine the relationship between MRE and regional climate change. We find that the MRE from east of Hainan Island is mainly modulated by the Southern Asian Summer Monsoon-induced precipitation (with 11.4% contributed to seawater), rather than wind induced upwelling. In contrast, in the relatively open seawater of Xisha Island, the MRE is dominated by the East Asian Winter Monsoon, with relatively more negative (lower) ΔR values associated with high wind speeds, implying horizontal transport of seawater. The average SCS ΔR value relative to the Marine20 curve is –161±39 14C years. Our finding highlights the essential role of monsoon in regulating the MRE in the northern SCS, in particularly the tight bond between east Asian winter monsoon and regional MRE.

Marine flooding events occasionally interrupted the everyday lives of prehistoric coastal populations. Identification of such events are important for studies of past population dynamics and adaptive strategies. However, short-term events are rarely identified in the geological record, which puts a severe limit on our archaeological interpretive framework. This paper explores the temporality of the second Holocene transgression in southwestern Norway (ca. 3500 BCE) and works under the hypothesis that it was not a slow geological process but rather one or multiple short-term events. A Bayesian approach is used to analyze multidisciplinary time series data collected from sites located in Norway and Shetland. The resulting chronological model supports the hypothesis that the second Holocene transgression in southwestern Norway was a rapid flooding event that occurred in the period 3445–3395 BCE (Early Neolithic II). It is also suggested, but not argued conclusively, that this flooding event could correspond to the Garth tsunami, a paleotsunami named after Garth Loch in Shetland. Considering the potential impact of such a flooding event on the everyday lives of local foragers who dwelled in southwestern Norway, it is anticipated that this study could form a starting point for future case studies.

In this paper we present new AMS radiocarbon dates from the Bronze Age cemetery of Tiszafüred-Majoroshalom excavated between 1961 and 1972. The cemetery provides crucial information on the cultural development and chronology of the Bronze Age Otomani-Füzesabony and the Tumulus cultures of Eastern Central Europe, in addition to the transition between the Middle and Late Bronze Age (approx. 1500 BC) in the Great Hungarian Plain.

In this paper, we examine cases where radiocarbon (14C) dates are incompatible with dates produced by other established archaeological methods. We present results from nine bones that we sampled from tombs in Phoenician sites in Sicily. These bones produced radiocarbon dates conflicting with established dates of finds in the associated tombs. These discrepancies, particularly in tomb dates, pose a serious problem, as they suggest that the finds may be disconnected from the buried individuals, challenging the fundamental premise of studying excavated tombs. To put our findings in a broader context, we also present other cases of discrepancies found in recent publications and note some common observations throughout these studies. Our questions and observations arise from the significant implications that radiocarbon dating has for our research on Phoenician ancient DNA, as these conflicts impact our understanding of the potential migration and movement of Phoenician people throughout the Mediterranean.

This date list reports the unpublished results from a multi-year radiocarbon dating program of the prehistoric Iapodes collection at the Archaeological Museum in Zagreb. Dated materials were excavated from cave, burial, and settlement contexts by various museum teams during the past century.

This paper presents an improved setup for radiocarbon analysis of water-soluble organic carbon based on wet chemical oxidation as installed at the Laboratory for the Analysis of Radiocarbon with AMS (LARA) at the University of Bern. The implementation of a non-dispersive infrared CO2 detector allows more precise and accurate quantification of carbon amounts in samples and establishes the possibility of simple monitoring of the efficacy of flushing and sampling processes. A detailed blank assessment unveiled undesired oxidation of different materials and sample temperature as critical factors regarding the level of constant contamination. Contamination arising from oxidation of septum pieces and carbon-based glues in conventional sampling needles was minimized by developing a glass-sintered needle. This new needle was also designed to be longer, reducing the minimum amount of sample solution needed to 2 mL. The oxidation time and temperature (1 hr at 75°C) were optimized to further decrease contamination during analyses of samples with carbon amounts of up to ∼50 µg. With these improvements, we now report low constant contamination levels of 0.62 ± 0.12 µg C (with F14C of 0.19 ± 0.04), whereas the cross contamination factor was determined to be 0.25 ± 0.07%.