The date of the Thera eruption has been a subject of intense debate since the mid-20th century. In recent years, the disagreements have escalated with the introduction of IntCal20. The increased number of annual measurements around the time period of the eruption has highlighted potential fluctuations in the atmospheric radiocarbon record, shedding new light on the date of the disastrous event. The Centre for Isotope Research in Groningen has already contributed data from this time period to IntCal20, and here, we report a new set of annual data of approximately 90 radiocarbon measurements between 1660 and 1507 BCE. We investigate the potential anomalies in the calibration curve and compare our dataset with those from other leading laboratories. Although we do not find compelling evidence of any rapid increases in radiocarbon production during this period, the results do point to the presence of minor differences between datasets which could be species, region or laboratory pretreatment related. By quantifying such offsets, we assess their impact on chronological models related to the eruption of Thera.

Welwitschia mirabilis, a unique gymnosperm native to Namibia and Angola, is a keystone plant species in the Namib Desert. It represents the only extremely long-lived non-clonal plant species occurring under hyperarid desert conditions, yet limited attempts have been made to accurately determine its age. Here, we present radiocarbon dates from a dead, sectioned Welwitschia of moderate size. We find the outer caudex tissue growth to progressively increase in age from the leaf base towards the ground level in this dwarf tree, while the inner cortex tissue becomes younger. Our sampling strategy revealed that the oldest tissue from this Welwitschia, found at the base of the caudex in the middle of the lobe, was dated to 531 ± 20 14C years, suggesting a vertical growth rate of approximately 0.47 to 0.67 mm/year. These findings can serve as a basis for future dating of larger, living individuals.

La Viña rock shelter is a relevant archaeological site for understanding the late Middle and Upper Palaeolithic cultural development in northern Iberia as evidenced by the Mousterian, Aurignacian, Gravettian, Solutrean and Magdalenian bone and lithic industries, parietal engravings and human subsistence remains recovered during the 1980s excavations by J. Fortea in the western and central excavation areas. This paper aims to present 16 new radiocarbon dates, which are added to the previous radiocarbon dates obtained, using different analytical methods on bone and charcoal. These are now 57 dates in total. Bayesian models have been applied to assess and discern the chronology of the archaeological sequence in each sector of the rock shelter. The results provide details on the chronostratigraphy of each excavation area, documenting the duration of the different technocultural phases and confirming in-site postdepositional events.

Iraya Volcano, situated at the northern tip of Batan Island in the Batanes group, marks the northernmost extent of the Philippine archipelago. Aside from the presence of accessible tephra deposits, the numerous archaeological sites on the island provide key insight into tephrochronology and volcanic hazard assessment. This paper presents stratigraphy and 21 radiocarbon ages of Holocene tephra layers distributed on the island. The eruption ages of the Holocene tephra are approximately 12.4 cal ka BP for Rolling Hills at the bottom, 4.5–4.9 cal ka BP for San Antonio, 2.1–2.5 cal ka BP for Mahatao, 1.6 cal ka BP for Basco, and 1.2–1.6 cal ka BP for Boulder Beach, with most of the tephra concentrated in the latter half of the Holocene. Artifacts excavated from Reydante Cabizon Property Site, San Antonio, Basco can be thought to date to around 4 to 2 cal ka BP, which is consistent with tephrochronology.

Archaeological investigations in the Prut-Dniester region during the Roman Imperial Period have yielded numerous Sarmatian culture necropolises and isolated graves. Establishing a precise chronology for these remains has long been a challenge due to the limitations of typological dating alone. This study integrates radiocarbon (14C) analysis of 11 human bone samples from selected funerary contexts with traditional typological methods, refining the chronological framework of the Sarmatian culture in this region. The radiocarbon analyses were subjected to Bayesian modeling, which allowed for the delineation of these samples into distinct phases, thereby adjusting and improving the periodization established through traditional methods. The results not only confirm but also refine previously established chronologies, offering deeper insights into the cultural, social, and economic dynamics of Sarmatian communities in the Prut-Dniester Barbaricum. These findings represent a significant contribution to the broader understanding of the Roman Imperial Period beyond the Eastern Limes.

This study presents a comparative analysis of the radiocarbon dates obtained on paired samples of various organic materials extracted from a lake sediment core. AMS radiocarbon dating of bulk sediment, chironomid capsules, and Trapa seeds was conducted to assess whether systematic offsets exist in the dates obtained on material that are commonly used to develop chronological frameworks for lake-based paleoenvironmental research. The findings reveal significant discrepancies between 14C dates obtained on bulk sediment, chironomid capsules, and on the Trapa seeds used to develop a previously published age-depth model for a sediment core recovered from Deoria Tal, Garhwal Himalaya, India. The systematic offset between the bulk sediment, and to a lesser extent chironomid remains, and the Trapa seeds is attributed to the integration of allochthonous carbon in the bulk sediment, leading to older apparent ages. The 3.6‰ shift in the δ13C value of the bulk sediment at 252 cm is inferred to reflect an increase in the contribution of C4 plant matter to the lake. The increase in enriched δ13C organic matter, coincident with the increasing offset between the dates obtained on bulk sediment and chironomids, and those obtained on the Trapa seeds, between 800 and 400 cal BP, was likely driven by anthropogenic land use changes, as evidenced by the four-fold increase in Cerealia-type pollen during this interval. This study underscores the necessity of selecting appropriate materials for radiocarbon dating to ensure accurate chronological reconstruction and highlights the potential of using chironomids remains to develop robust radiocarbon chronologies for lake sediment records.

The Kura-Araxes culture spread over a large area of South-west Asia, participating in the transformational dynamics of Early Bronze Age societies in the region. Yet, the absence of a robust chronological framework for this cultural horizon hinders its integration into wider regional and interregional models. Drawing on a substantial new radiocarbon dataset, collating novel Bayesian chronological models for eight sites and existing data from the wider region, this article identifies settlement patterns that coincide with broader reconfigurations of the Kura-Araxes cultural landscape, which in turn track socioeconomic, and possibly political, shifts observed in eastern Anatolia and the greater Near East.

The programme of radiocarbon dating undertaken at Stanwick, Northamptonshire, demonstrates the value of scientific dating of Romano-British sites, including those with good pottery sequences and large numbers of datable coins and other finds. It has refined and clarified the chronology and phasing of the site, particularly in its final phase of occupation. It confirmed some of our original dating of the human burials, and showed other dates were significantly wrong. It also addresses issues relating to the calibration of radiocarbon dates and dietary isotopes in the period. This has enabled us to identify activities, material culture and burial practices current at Stanwick and elsewhere in the immediate post-Roman period.

McEuen Cave (AZ W:13:6 (ASM)) is a large bedrock rockshelter located within an andesitic rocky ash flow tuff/ignimbrite within the Bureau of Land Management’s Fishhooks Wilderness Area near Fort Thomas, Arizona. Exceptional preservation at the site has produced an extensive assemblage of perishable artifacts, including a tremendous quantity of cultigen remains radiocarbon dated between 3600 BP and 1250 BP. In this paper, we provide the results of a new radiocarbon dating effort aimed at identifying additional early Silverbell Interval cultigens and clarifying the intensity and persistence of Early Agricultural Period occupation. Our goal is to better understand the age and extent of early cultivation activities within this high-elevation wilderness and contextualize the remains from this site with the more thoroughly understood co-eval Early Agricultural Period villages evidenced along major riverways such as the San Pedro and Santa Cruz in southern Arizona. [Spanish language abstract: La cueva McEuen (AZ W:13:6 (ASM)) es un gran refugio rocoso de lecho rocoso ubicado dentro de una toba/ignimbrita de flujo de cenizas rocosas andesíticas dentro del área silvestre Fishhooks de la Oficina de Administración de Tierras cerca de Fort Thomas, Arizona. La preservación excepcional en el sitio ha producido un extenso conjunto de artefactos perecederos, incluyendo una tremenda cantidad de restos de cultígenos fechados por radiocarbono entre 3600 BP y 1250 BP. En este documento, proporcionamos los resultados de un nuevo esfuerzo de datación por radiocarbono destinado a identificar cultígenos adicionales del Arcaico tardío-medio y aclarar la intensidad y persistencia de la ocupación del Período Agrícola Temprano. Nuestro objetivo es comprender mejor la edad y el alcance de las actividades de cultivo tempranas dentro de este desierto de gran altitud y contextualizar los restos de este sitio con las aldeas coeval del Período Agrícola Temprano mejor entendidas evidenciadas a lo largo de las principales vías fluviales como el San Pedro y el Santa Cruz en el sur de Arizona.]

We report a new relative sea level curve from Inglefield Land, northwest Greenland, to investigate the transition from maximum to minimum loading across Nares Strait. We sampled marine bivalves and terrestrial macrofossils for radiocarbon dating from raised marine terraces in Rensselaer Valley, Inglefield Land (78.58°N, 70.71°W) to constrain relative sea level through the Holocene. The oldest terrestrial macrofossil of 9010–8650 cal yr BP provides a minimum-limiting constraint for the deglaciation. Sea level fell rapidly from the marine limit at 85 ± 4 m to 37.5 ± 4 m above sea level (m asl) between 9010–8650 and 7970–7790 cal yr BP at a rate of 49 m/ka. The rate of sea -level fall decreased to 11 m/ka between 7970–7790 and 5320–5060 cal yr BP, when it fell from 37.5 ± 4 to 9 ± 4 m asl. After 5,320–5,060 cal yr BP, we estimate sea level fell at a lower rate of 2 m/ka to modern sea level. The period of fastest emergence in Inglefield Land is earlier in time than in Hall Land, reflecting earlier deglaciation, and is steeper than in Hall Land and Washington Land. This sea-level history captures the transition from the style of emergence from Pituffik to Hall Land.

We investigated radiocarbon dates of human bone samples from several medieval sites in Trondheim, central Norway. Stable isotope data was used to estimate marine correction for the radiocarbon dates, which is necessary to correct the radiocarbon ages and establish age models for the archaeological layers. We observed that a marine correction without ΔR does not lead to a well-defined model for all sites. Allowing a variable ΔR improves the model, which indicates that food sources and trade routes have changed over time, influencing the mobility of food resources as well as of people. However, this does not work for all sites, indicating that variation of reservoir ages could also be the result of individual preferences for the food and that fish with different ΔR, and thus different geographical origin, was consumed during the same periods. Many radiocarbon and stable isotope (δ13C, δ15N) measurements have been carried out for the project. We calculated %marine consumption from the isotope values and found that it varies greatly, between 7% and 51%, and apparently independent of period, social status, churchyard location or other factors. Based on these data, we determined average reservoir ages for the marine food consumed in Trondheim during different phases, varying between ΔR = –150 and 280 years.

The use of ultrafiltration remains a subject of ongoing debate among pretreatment methods employed in radiocarbon dating of mammalian archaeological bone. However, such discourse had not previously extended to the archaeology of the Canary Islands (Spain), where detailed descriptions of laboratory processing methods for collagen purification often remain absent. Our study presents a case study involving a new set of radiocarbon dates obtained from the remains of ancient natives of Tenerife Island. For the first time in this region, we compared the results of ultrafiltered with non-ultrafiltered collagen from the same individuals, focusing on the method’s implications for dating accuracy in the Canaries. Through an examination of the cleaning protocols of ultrafilters and an assessment of the reliability of radiocarbon dating outcomes, we have found that ultrafiltration may influence the accuracy of results. However, given the additional handling required and the potential risk of contaminating the samples, its application should be carefully considered. In the context of the Canary Islands, ultrafiltration may be most relevant for samples associated with early human occupation, though further research is needed to assess its necessity across different biogeographical contexts. This communication further contributes to a broader understanding of preparation methods for radiocarbon dating bone from various environmental contexts, emphasizing the uniqueness of each case. Furthermore, we discuss the implications of our findings for archaeological research in the Canary Islands, highlighting the methodological gaps that persist in the region and underscoring the importance of ensuring the accuracy and reliability of chronological interpretations in archaeological investigations.

Using calibrated radiocarbon dates, this study investigates climate signals recorded in fluvial sedimentary archives from southern Poland, eastern Netherlands, and eastern Germany. Summed probability density functions (PDFs) were constructed and analyzed in the context of INTIMATE stratigraphy. The results indicate that fluvial sedimentation and erosion processes were closely linked to climate fluctuations, particularly during GS/GI and GI/GS transitions. The analyses indicate multi-scale relationships between regional geomorphological processes and global climate trends during the period from 50 to 15 cal kBP. This study provides a reconstruction of Late Pleistocene fluvial activity and highlights the need for more precise radiocarbon dates to refine correlations between regional and global climate events.

In recent decades, numerous excavations have been conducted at prehistoric sites in northwestern Iran, and the results of these studies have contributed to the development of a chronological framework for the region. The early Chalcolithic period in this area is referred to as the Dalma or Hasanlu X period. Various theories have been proposed regarding the chronological span of this culture, yet challenges and debates about its dating remain. The Belachak 3 site is one of the settlements attributed to this period, excavated by the first author of this article. The excavation results indicate that the site was temporarily occupied. The pottery recovered from this site closely resembles the ceramics found at well-known Dalma sites such as Dalma Tepe and Nad Ali Beig. This article aims first to explore the relative and absolute chronology of the Belachak 3 site. Subsequently, it evaluates the dating of this culture based on the absolute chronology of this and other Chalcolithic sites in western and northwestern Iran. For dating Belachak 3, five animal bones were sent to the Poznań Radiocarbon Laboratory. The results indicate that the site was occupied around 5000–4700 BCE. Additionally, based on the pottery findings and absolute dating, it can be suggested that the Dalma culture likely emerged in the late 6th millennium BCE and became widespread across large areas of western and northwestern Iran from around 5000 BCE onward.

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.

An increase in knowledge is usually beneficial but can also highlight misapprehensions of existing data. Such is the case for the Pictish-Norse transition in Northern Scotland in the later first millennium AD. New radiocarbon dates from the key ‘transitional’ settlement of Buckquoy, Orkney, reveal that traits previously published as indicative of incoming Norse influence pre-date the start of the Viking Age, suggesting a greater level of endogenous change than hitherto has been appreciated. Here, the authors underscore the need for a re-evaluation of other settlement sequences across the later Pictish and early Norse periods, reopening many questions about the transition.

The Darband Wall in southern Uzbekistan marks an important political border in the Classical world, yet the dating of its construction is largely relative and contested. Presenting 10 new radiocarbon dates from the wall, the authors argue that construction began in the early or middle third century BC, likely under Seleucid or early Greco-Bactrian rule, while later reconstruction efforts coincide with Kushan expansion around the first and second centuries AD. Early Hellenistic-style fortifications reveal a defensive, and possibly an orientational, shift during Kushan rule that underscores both the strategic significance of the wall and the need for more extensive investigation.

The emergence, on the Loess Plateau of Central China, of settlements enclosed by circular ditches has engendered lively debate about the function of these (often extensive) ditch systems. Here, the authors report on a suite of new dates and sedimentological analyses from the late Yangshao (5300–4800 BP) triple-ditch system at the Shuanghuaishu site, Henan Province. Exploitation of natural topographic variations, and evidence for ditch maintenance and varied water flows, suggests a key function in hydrological management, while temporal overlap in the use of these three ditches reveals the large scale of this endeavour to adapt to the pressures of the natural environment.

This study from the Accelerator Mass Spectrometry Laboratory at the Center for Physical Sciences and Technology (FTMC), Vilnius, Lithuania, presents a detailed description of the sample preparation methods employed in the laboratory, with a focus on two AMS systems: a single-stage accelerator mass spectrometer (SSAMS) and a low energy accelerator (LEA). A pivotal aspect of this article is our participation in the GIRI intercomparison test, demonstrating our commitment to precision and accuracy in radiocarbon dating, with the average z-score values of the GIRI test being 0.16 ± 1.66 for SSAMS and –0.04 ± 1.52 for LEA. The outcomes from this participation validate the meticulous sample preparation procedures at Vilnius Accelerator Mass Spectrometry Laboratory and offer significant insights into the efficiency and reliability of SSAMS and LEA systems, contributing to a better understanding of their capabilities in radiocarbon analysis.