This article examines the radiocarbon chronology of Tes’ and Tashtyk burial sites in the Minusinsk Basin of Southern Siberia. This region is known for its remarkable diversity of burial constructions and highly complex mortuary practices in the post-Scythian period (2nd century BC to 6th century AD). Based on 168 radiocarbon dates, we traced the chronology and variability of burial practices throughout this period. For the first time, a representative series of radiocarbon dates for Tashtyk crypts has been obtained, demonstrating that crypts were constructed synchronously with various types of Tashtyk burials in late 1st–6th centuries AD. Unique mortuary practices, involving the posthumous preservation of corpses and the creation of anthropomorphic effigies and dolls, often featuring clay-plaster “masks,” remained in practice for at least 700 years, spanning both the Tes’ and Tashtyk periods. Bayesian modeling reveals the coexistence of the Tes’ and Tashtyk sites during the 1st–3rd centuries AD, which allows us to suggest a smooth and gradual transition from one culture to another.

The Salapunku archaeological site is located within the Historic Sanctuary – National Archaeological Park of Machu Picchu (HS-NAPM) in the Cusco area of Peru. Although Salapunku is related to the Inca settlements of the HS-NAPM, during archaeological excavations, we distinguished different moments of cultural occupation from the earliest human presence to complex pre-Hispanic societies such as the Inca and finally to the colonial period. Previous research on the site’s chronology was based on typological analyses of pottery and other artifacts found during archaeological research. This radiocarbon analysis, the first of its kind in this area, establishes a chronology of the cultural history of this significant settlement, considered the gateway to the Cordillera of Vilcabamba.

Estimates of marine reservoir corrections (ΔR) in the southeastern Arabian Sea region are limited. To better constrain the region’s marine reservoir corrections, additional pre-bomb radiocarbon records are needed. In this context, a coral core from the Lakshadweep archipelago in the southeastern Arabian Sea has been analyzed to measure its radiocarbon content. Pre-bomb radiocarbon values from the coral record are used to estimate the marine reservoir correction value of the region. The mean ΔR value of the Lakshadweep region is calculated to be –128 ± 130 yr. The comparison of available ΔR values from the Arabian Sea region shows that the mean ΔR value of the eastern Arabian Sea is significantly lower than that of the northern and western Arabian Sea. The low ΔR values from the eastern Arabian Sea likely indicate the influence of relatively 14C-enriched Bay of Bengal water in the region.

The southwestern Atlantic margin plays a crucial role in understanding ocean circulation, with the Brazil Current (BC) driving surface flow and various water masses (TW, SACW, AAIW, UCDW, NADW, LCDW) influencing different depths. The Santos Basin, a marginal basin formed following the breakup of Gondwana, remains understudied with respect to late Quaternary sedimentary processes, and the recent literature offers conflicting interpretations of sediment sources and depositional processes. Additionally, radiocarbon data for this region are scarce, and calibration uncertainties and regional reservoir effects have limited previous studies. This study compiles a comprehensive radiocarbon dataset (264 datings from 70 sediment cores) for the upper to middle slope of the Santos Basin (120–2000 mbsl), combining published and unpublished data (69 new ages). Previously published ages were recalibrated using Marine20 and SHCal20 curves, applying a regional ΔR correction. The dataset, showing minimal age inversions, provides a robust foundation for future research on late Quaternary sedimentary and paleoenvironmental dynamics in the southwestern Atlantic.

We present a short database of the mole fraction of CO2 and 14CO2 in atmospheric air samples from an urban area in Gliwice, Silesia, Poland. The research covered a period from August 2023 to July 2024. A new laboratory air sampler stand was established to monitor carbon dioxide levels in Gliwice, giving the possibility to determine CO2 levels in the air using appropriate instruments to collect the air samples, extract CO2 from them, and thus measure carbon isotopes ratio 14C/12C. The analysis of the mole fraction of CO2 was determined using a low-cost system (CARBOCAP GMP343), while the carbon isotopes concentration was measured using MICADAS. The 14C in the air samples varied randomly from –55 to –24‰, while the monthly mole fraction of CO2 varied from 428 to 470 ppm. It has been also observed also that CO2 concentration is linked with the planetary boundary layer. The fraction of fossil of total CO2 has been estimated at the level of 2.5% during the investigated period of time. Another aim of this study was to investigate pine needles as 14C archives in a contemporary environment. The examination of the needles was based on the analysis of the similarities and differences in radiocarbon concentrations in pine needles of various ages collected in the middle of consecutive seasons, with 3 months resolution in Gliwice. The concentration of 14C in the needles was determined using a liquid scintillation counter. The mean F14C from all the samples was 99.80(70) pMC.

The carbon isotopic compositions (δ13C and Δ14C) of dissolved inorganic carbon (DIC) in water samples are influenced by various storage conditions, but the extent and mechanisms of these changes remain unclear. In this study, we systematically evaluated the effects of storage temperature, pretreatment (filtration and addition of mercuric chloride, HgCl2), and container material (glass vs. plastic) on δ13CDIC and Δ14CDIC. The δ13CDIC values in samples preserved with HgCl2 exhibited the smallest variation (δ13CDICmax−δ13CDICmin ranging from 0.7‰ to 1.0‰), followed by those stored under refrigeration (∼4°C; variations of 1.3‰ to 1.4‰). These storage conditions also effectively constrained variations in Δ14CDIC over storage periods of up to 60 days in polyethylene terephthalate (PET) bottles. In contrast, comparisons with glass bottles, combined with analysis of PET-derived compounds and associated enzymatic activity, indicated that the degradation of PET-derived compounds provided a plausible explanation for the observed radiocarbon depletion. For long-term storage (>110 days), isotopic fractionation was primarily governed by exchange between DIC and atmospheric CO2, attributable to the permeability of PET bottles. This study provides a quantitative, mechanism-based assessment of storage-induced effects on δ13CDIC and Δ14CDIC, offering practical guidance for minimizing storage-induced uncertainty in carbon isotopic studies.

Within a collaboration between the Brazilian Federal Police and the Radiocarbon Laboratory of the Fluminense Federal University (LAC-UFF), this work studies seized art objects made from ivory. We aim to develop protocols to verify whether they are illegal according to the Convention on International Trade of Endangered Species from Wild Flora and Fauna (CITES) law by measuring the carbon-14 concentration in the modified ivory samples from different sampling spots and comparing it to the bomb peak curve. Over the course of this research, we evaluate the uncertainties related to the determination of the elephants’ death. These uncertainties are due to several factors such as the provenance of the elephants, growth pattern of the tusks and incorporation of atmospheric radiocarbon to the tissues, sampling methods of ivory objects of different sizes and shapes, and radiocarbon data analysis. This work is a pioneer study in Brazil and is likely to become a reference in the country in the field of radiocarbon analyses in forensic contexts.

This work aims to clarify the absolute chronology of the construction phases of the St. Peter and Paul Rotunda at Budeč, focusing on the erection of the rotunda and the tower. Fifteen mortar samples were taken from various structural parts, two of which also contained remnants of charcoal. The mortar samples were mechanically treated to extract a purified calcitic binder that was dated by radiocarbon analysis. The effectiveness of the sample pretreatment methodology was assessed by means of cathodoluminescence microscopy. Thin sections of mortars were characterized by polarized light microscopy. The petrographic characterization allowed for the samples to be grouped according to their binder, aggregate, and structure. This was compared with the evaluation of the calibrated dates, expected chronology known from legends, as well as with formal and stylistic analyses of the structure. The radiocarbon dating distinguished the different construction phases well, and the accuracy and reliability of the dating is discussed. The presence of silts and clays probably led to geogenic carbon contamination of the samples from the foundations, as the obtained dates are older than expected. These dating results were thus regarded as inconclusive. However, the samples from the vaulted dome of the rotunda did not show any anomalies, and the calibrated date period obtained was regarded as relevant and thus successfully dated. The dating based on the legends also fits the determined interval.

River deltas play a crucial role in the global carbon cycle, acting both as significant carbon sinks and as sources of CO₂ to the atmosphere. The Rhône River delta is a key site for studying these processes due to its high sedimentation rates and its unique radiocarbon signatures influenced by anthropogenic activities. This study compiles over 10 years of research to assess the sources and fate of organic matter (OM) in the Rhône River delta, using stable (δ13C) and radiogenic (Δ14C) carbon isotopes. New data from the MissRhoDia II campaign (2018) are compared with previous datasets (CarboRhone 2012; DICASE 2014) to analyze the interactions between terrestrial, riverine, and marine OM sources. The study examines sedimentary processes along a transect from the river mouth to the continental shelf, considering both sediment burial and porewater analyses. Results indicate that OM mineralized in proximal sediments is primarily of terrestrial origin, freshly supplied by the river, and potentially influenced by nuclear-related activity. In contrast, on the continental shelf, remineralization occurs at a slower rate due to the limited availability of organic substrate and isotopic signatures reveal a predominantly marine origin with a minimal anthropogenic influence. In the Rhône pro-delta sediments, the burial of radiocarbon-free organic carbon (aOC) underscores the role of sediment transport in long-term carbon storage, with contributions from both petrogenic and aged terrestrial organic carbon sources. The mineralization of young, labile carbon and the burial of more refractory carbon create significant differences between the 14C signatures measured in porewaters and sediments, highlighting the need to analyze both compartments. This study improves our understanding of carbon dynamics in the Rhône delta and provides valuable perspectives to better understand coastal carbon budgets, carbon sources, as well as the anthropogenic influence on marine ecosystems.

The Yucatán Peninsula, Mexico, has many shallow coastal lagoons. The interest in the study of mangroves and other ecosystems in this area is due to their capacity to store large amounts of organic carbon (blue carbon). To understand this process, sediments can provide information about the evolution over time of the coastal zone, through changes in their physical and chemical composition.

Isotopic techniques have proven to be useful in the study of different coastal processes such as carbon sequestration rates and other events. However, coastal ecosystems are dynamic regions that change over time, representing a challenge for dating with nuclides such as 14C. Previous studies have focused on the dating of fractions of different sizes or fractions in which the carbon comes from different sources. These strategies help to find the most probable date of deposition of the sediments.

In this study we dated 14C paleosol sediment fractions obtained from mangrove-dominated areas that have undergone a transformation process. We dated different fractions such as macrofossils, total organic matter, humin, and humic acids, from sediment cores collected from two paleosol sites with different geological and hydrological characteristics: Jaina in Campeche and Ría Lagartos in Yucatán, Mexico. In both cores we observed that in the absence of macrofossils, the fractions that indicate the best age to report are total organic matter or humin.

With the development of radiocarbon dating methods in the last decade, the Andean archaeological community has successfully leaned into the problem of the chronology of the expansion of the Inca State. While this chronology was based on ethnohistorical accounts (Rowe 1945), it has been possible to verify its foundations precisely in the last decade. The results from the Maucallacta region are part of these discussions and are intended to add new data from the Inca province of Kuntisuyu, which was neglected in this debate until now. The project encompasses archaeological investigations near the snow-covered volcano Coropuna, frequently mentioned by chroniclers of the 16th and 17th centuries as an oracle worshiped since pre-Inca times. This includes a large complex known as Maucallacta-Pampacolca, located approximately 170 km northwest of Arequipa in the southern highlands of Peru, within the District of Pampacolca, Province of Castilla, Department of Arequipa (LS; 3750 m asl). Due to its location, it holds a unique relationship with the Coropuna landscape. The site is a vast administrative center featuring over three hundred stone buildings, tombs, and ceremonial structures. Among them, the most important is the large ceremonial platform with ushnu and the dumps deposited beneath it. The analysis of ceramics and animal bones, combined with stratigraphic analysis and the results of new calibrations and interpretations of radiocarbon dates, provides a comprehensive picture of the formation and use of ceremonial dumps at the site, making them one of the most thoroughly examined collections in this regard.

A 200 kV Mini Carbon Dating System (MICADAS) was installed and has been in operation since June of 2023 at Henan University (HENU-AMS). The laboratory (namely HENU-AMS Laboratory) is equipped with an Automated Graphitization Equipment (AGE3), a Carbonate Handling System (CHS2), and a Gas Ion Source Interface System (GIS). The MICADAS can measure both graphite and CO2 samples. The system was firstly tested on the international reference materials, and the test yielded a linear fit with R2> 0.9999. A series of our own samples of different ages and different targets (dating materials) that were already dated in other accelerator mass spectrometry laboratories were then analyzed in our laboratory, and our dating results were quite comparable with those from other laboratories. Specifically, the R2 of our dating results with those from other laboratories is as high as 0.9967 (n = 12). Up to the date of this report (31 July 2025), the system has completed measurements of over 2500 samples.

Antiquities in the Middle East region face various threats, including illicit trade, theft, and forgery. This research examines a leather manuscript obtained by the Palestinian Tourist Police following the arrest of an antiquities smuggler. The manuscript contains Phoenician inscriptions along with symbols such as the Menorah, Shofar, and a plant branch. Radiocarbon dating using accelerator mass spectrometry (AMS) techniques determined the manuscript’s date to be post-1950 CE. Therefore, the results indicate that the manuscript is a modern forgery, likely created for commercial purposes. Additionally, the text contains several grammatical errors, further supporting the conclusion that it is not an authentic historical artifact.

Oil contamination in estuarine and coastal ecosystems presents major challenges for environmental monitoring due to the complex mixture of organic matter from biogenic and petrogenic sources. This review synthesizes recent advances and limitations in the combined use of carbon isotopes δ13C and Δ14C to trace petroleum contamination in marine sediments. Sixteen empirical studies were analyzed to evaluate the effectiveness of this dual-isotope approach in identifying fossil carbon, estimating its degradation state, and assessing its environmental persistence. While δ13C provides insights into organic matter sources and transformation, Δ14C offers a sensitive tracer for detecting fossil carbon inputs, even in low concentrations or mixed matrices. The review highlights how their integration strengthens source attribution and enhances the resolution of hydrocarbon monitoring in dynamic coastal settings. An exploratory typology based on Δ14C and Fm is proposed to semi-quantitatively classify contamination severity and support cross-study comparisons. Despite its potential, the approach faces challenges such as high analytical costs, limited laboratory access, and a lack of methodological standardization. Future efforts should focus on integrating compound-specific isotope analysis, expanding applications in mangrove ecosystems, and refining interpretative models to improve the forensic utility of carbon isotopes in oil spill investigations. This review contributes to the systematization of isotopic methods in environmental forensics and reinforces their role in tracing petroleum-derived carbon in sensitive coastal environments.

The radiocarbon content of dissolved inorganic carbon (DIC: CO2(aq), HCO3–, CO32–) and gaseous CO2 can provide valuable information for the cycling and residence time of carbon in groundwaters, porewaters, hydrocarbon reservoirs, methane seeps, and hydrothermal systems. Fluids and gases from these systems often contain high concentrations of hydrogen sulfide (H2S) that interferes with critical steps of the analytical procedure, particularly the reduction of CO2 to graphite. We developed and tested a simple and effective method to remove H2S from water and gas samples prior to graphitization by passing the gas through a silver nitrate solution in dilute nitric acid. The resulting cleaned CO2 was sufficiently pure to be reduced to graphite by hydrogen on an iron catalyst. The mass of the process blank of this method is negligible (0.45 ± 0.10 µg C, with F14C of 0.30 ± 0.20) and almost identical to our process blanks without the H2S trap (0.43 ± 0.10 µg C, F14C = 0.30 ± 0.10). The method has been successfully applied to samples containing elevated H2S from multiple hydrothermal vent fluids.

In recent times, forensic science has increasingly relied on methods that use stable and radioactive isotope analysis to identify human remains. The use of 14C-AMS dating of dental enamel and dentine of an individual allows the estimation of the year of birth, while that of stable isotopes of carbon and oxygen can provide information on their geographical origin. Isotopic analysis of a tissue complements existing identification techniques, enhancing the capacity to refine, exclude, and affirm investigative approaches directed towards individual identification.

The primary aim of this exploratory study is to amalgamate diverse isotopic methodologies conducive to the prompt and accurate identification of a deceased individual. In this manuscript, we elucidate the application of a rapid processing technique for whole molars from individuals with documented ages, employed to ascertain age through 14C-AMS dating. Furthermore, an investigation was undertaken to assess the capacity of carbon and oxygen-stable isotopes in distinguishing regional disparities. To achieve this, we conducted a comparative analysis of tooth samples sourced from individuals residing in three cities within the Mexican Republic: Mexico City in the central region, Oaxaca City in the southern region, and Tepic Nayarit on the western Pacific coast. The age of dental piece formation, as estimated through 14C-AMS, exhibited a precise correlation with the actual age. By means of the stable isotope outcomes, the data disclosed substantial disparities in 13C and 18O abundances among teeth from individuals residing in the three cities.

We report the results of radiocarbon dating performed at the ETH laboratory on soft tissue of the mummified body found in September 1991 on the Hauslabjoch in the Ötztaler Alps (near the Similaun Mountain), South Tyrol. Over the past three decades, additional analyses of the sample, which had been stored frozen in a glass jar, have improved the precision of the first published radiocarbon ages. The frozen jar and the story of a mummified body found in the Alps fascinated visitors to the laboratory, mostly primary and high-school students. As part of educational projects, 11 samples were prepared and analyzed, yielding a combined radiocarbon age of 4525 ± 7 BP. This agreement with 4550 ± 27 BP, i.e., the very first results by Bonani et al. (1994), highlights the quality of the analysis performed decades ago. The combined age of all the 14C ages measured at the ETH laboratory is 4527 ± 7 BP.

Plant remains of human workmanship, preserved in ancient settlements, provide evidence for reconstructing the history of the man-plant relationship. A number of ancient habitational settlements have come to light in the alluvial plains of the Gangetic Valley. However, only a few sites from the Neolithic, Chalcolithic, and Iron Age periods have been excavated and studied for the plant-based subsistence economy in the Gangetic Valley. The information from the Early Historic times is too limited to draw conclusions about cropping patterns or agricultural strategies, or to evaluate long-term continuity or change in eastern India, compared with better-documented developments in northern and north-western India. The present study from Ajatshatru-ka-Quilla Maidan in Nalanda District, Bihar, is the first attempt to explore the agricultural economy during the Mauryan and Sunga-Kushana cultures in the light of information from preceding Neolithic and Chalcolithic sites in the region.