Radiocarbon Dating Research Articles

The Future of Periodization. Dissecting the Legacy of Culture History

This paper discusses the future role of periodization in the wake of recent critiques of culture-historical chronologies concurrent with the rise of high-definition radiocarbon dating. It is argued that periodization has two distinct facets, a narrative function and a dating function, which should be separated. Archaeology may eventually be able to abandon the latter, but not the former. However, the two aspects are closely intertwined and the goal of this paper is to disentangle them and, through a case study of archaeological periodization in Iceland, demonstrate the need to re-engage with culture-historical taxonomies by reverse engineering their construction. Only in this way will the utility or poverty of such culture-historical periods be exposed to proper scrutiny and the ground cleared for building new, narrative periodizations.

Modelling diffusion of innovation curves using radiocarbon data

Archaeological data provide a potential to investigate the diffusion of technological and cultural traits. However, much of this research agenda currently needs more formal quantitative methods to address small sample sizes and chronological uncertainty. This paper introduces a novel Bayesian framework for inferring the shape of diffusion curves using radiocarbon data associated with the presence/absence of a particular innovation. We developed two distinct approaches: 1) a hierarchical model that enables the fitting of an s-shaped diffusion curve whilst accounting for inter-site variations in the probability of sampling the innovation itself, and 2) a non-parametric model that can estimate the changing proportion of the innovation across user-defined time-blocks. The robustness of the two approaches was first tested against simulated datasets and then applied to investigate three case studies, the first pair on the diffusion of farming in prehistoric Japan and Britain and the third on cycles of changes in the burial practices of later prehistoric Britain.

Combined optically stimulated luminescence and radiocarbon dating of aeolian dunes in Arctic Sweden

AbstractMultiple parabolic sand dune fields formed in Arctic Sweden after the last deglaciation, facilitated by an abundance of loose glaciofluvial sediment, limited vegetation cover and strong winds. Following initial stabilisation, these dunes underwent repeated reworking after fire events, as evidenced by the presence of buried soils, charcoal layers and redeposited sands in the dune stratigraphy. These reworking events may be driven by wider climate forcing; however, to date, no chronological framework exists for this activity in Sweden. As such, here, we apply quartz optically stimulated luminescence (OSL) dating of Arctic Swedish sand dunes using two dunes at the sites of Vastakielinen and Jorggástat. Resultant double‐SAR (single aliquot regenerative dose) quartz OSL ages are in good agreement with independent ages provided by 14C dating of charcoal fragments recovered from charcoal layers within the dunes, and we conclude that the chosen protocol is generally well suited for dating aeolian reworking of dune sediments in Arctic Sweden. While feldspar contamination limits precise age assignment for initial dune movement, our results nonetheless suggest repeated and long‐lasting aeolian activity in Arctic Sweden throughout the Holocene and, although there are differences in detail, further suggest some general trends in terms of dune stability and reworking over Arctic Fennoscandia.

Dynamic Funerary Monuments of North-western Europe: Chronological Modelling of a Late Neolithic–Pre-Roman Iron Age Cemetery Complex at Mang de Bargen, Northern Germany

This study presents the first extensive radiocarbon dating programme of Bronze Age material from northern Germany, and it combines radiocarbon dates, relative typo-chronological date ranges, and stratigraphic data within a Bayesian chronological framework. We estimate the cemetery complex at Mang de Bargen (Bornhöved, distr. Segeberg, Schleswig-Holstein) to be in use for more than two millennia, which is exceptionally long in northern Germany and in a wider European context. The site provides a unique insight into the dynamic nature of burial monuments and associated burial practices, from the Late Neolithic and into the Pre-Roman Iron Age (c. 2500–50 bc). The barrow building tradition lasted around a millennium (c. 2350 –1300 bc), with several barrows in concurrent use. The barrows were persistently re-used as burial ground, both within ‘living memory’ of the primary graves, but also long after. The burial intensity varied over the cemetery’s use-life, with distinct peaks in the Late Neolithic, when the first barrows were erected; in the Older Bronze Age when more barrows were erected; in the Younger Bronze Age, when secondary cremation graves were added to existing barrows; and finally in the Pre-Roman Iron Age, with the addition of an urnfield. The funerary rituals vary considerably over the period: from inhumation to cremation, and from primary and secondary graves in barrows to flat graves. Cremation was introduced in the 14th century bc but inhumation and cremation were used in parallel for around a century before the former ritual was abandoned c. 1300 bc. The study provides absolute chronological distributions of the grave types present at Mang de Bargen and shows them to be comparable to other sites at a regional and over-regional scale, successfully demonstrating how new types were quickly adopted across large parts of north-western Europe.

Interactions between local glaciers and adjacent grounded Ross Sea ice in the Royal Society Range, Antarctica

The Antarctic Ice Sheet (AIS) has the potential to exert a major control on future global sea level. Here, we gain insight into the response of the Antarctic Ice Sheet (AIS) to changing climate through assessment of ice-sheet behavior during and since the Last Glacial Maximum (LGM) along the western coast of McMurdo Sound. We examine whether expansion of grounded ice in this sector of the Ross Embayment during the last glaciation was caused by increased flux from East Antarctic outlets and local glaciers or was produced by marine influences, such as lowered sea level or reduced melting of submarine grounded ice. During the LGM, grounded ice derived from the Ross Sea deposited a well-defined drift sheet along the Royal Society headlands on the western coast of McMurdo Sound. Twenty-six new radiocarbon dates of subfossil algae within this drift sheet suggest that the ice sheet was at its maximum extent by at least ∼18.4 ka and maintained this position for about five thousand years. Cross-cutting relationships show that local alpine glaciers did not contribute to the grounded ice but rather fluctuated asynchronously. This same relationship held true during the penultimate glaciation, dated to roughly 137–191 ka with 10Be exposure ages. An explanation for this out-of-phase relationship is that different mechanisms controlled their respective extents. Because they lack significant surface melting ablation zones, the local alpine glaciers, which largely terminate on land, were driven by changes in accumulation. These glaciers likely expanded during warmer times when accumulation was higher. In contrast, marine factors, such as global sea-level change and/or subglacial melting, controlled ice fluctuations in the Ross Embayment, including McMurdo Sound, leading to advance during the LGM.

A Chronological Model for Inca Provincial Expansion: The Case of the Copiapo Valley

Abstract This article examines a new dataset of radiocarbon dates that provides insights into the progressive installation of Inca infrastructure in the Copiapo Valley, situated at the southern edge of the Atacama Desert in northern Chile. It shows that the Inca imperial expansion in this region was not a linear process and was likely shaped by local negotiations and conflicts. The findings describe three main stages of Inca expansion. The first is the construction of the North–South Inca Road and the establishment of high-altitude mountain shrines. The next stage consisted of a physical intervention in a local village located in the upper valley, including the construction of administrative buildings and public spaces. The last stage involved indirect intervention in local villages, characterized by the presence of isolated administrative buildings that were potentially used for diplomacy and negotiation. I argue that the Inca imperial expansion, characterized by evolving strategies across regions and time periods, not only demonstrates the state's capacity for learning but also suggests the pivotal role of local actors in positions of power who wielded agency to shape these developments.

Tracking Mississippian Migrations from the Central Mississippi Valley to the Ridge and Valley with a Unified Absolute Chronology

AbstractAs regional chronologies become better defined, we are better able to track large-scale population movements and related cultural change. A dataset of 156 radiocarbon dates from the Middle Cumberland Region (MCR), evaluated with 199 more dates from the Ridge and Valley portions of northern Georgia and East Tennessee, enable modeling of population movements from the Central Mississippi Valley into the MCR, as well as subsequent movements and effects in the Ridge and Valley between AD 1200 and 1450. The dissolution of Cahokia is of particular interest, because the MCR falls geographically between the American Bottom and the Ridge and Valley province. This large-scale chronological perspective places key events in this part of the Southeast and Midwest into a unified historical framework that increases our understanding of the timing of cultural events. A related goal is to sort out possible external events and influences that may have affected this large region. This study makes apparent the relationships between cultural events and natural events, such as the drought sequences reported for the Central Mississippi Valley and beyond.

Lithological features of Lake Bannoe sediments (Southern Urals) as an indicator of environmental and climate changes in the Holocene

Research subject. Bottom sediments of Lake Bannoe (Southern Urals). Aim. Identification of lithologic features of Lake Bannoe sediments, which could reflect sedimentation conditions in the Holocene. Materials and methods. The detailed complex analysis included radiocarbon dating, grain-size analysis, X-ray diffraction analysis, electron microscopy, X-ray fluorescence and isotope analysis, coercive spectrometry and pollen analysis. Results. Radiocarbon dating showed that sedimentation in Lake Bannoe began no later than ~13 thousand years ago. Combination of data from various laboratory studies unraveled four lithological zones and the corresponding stages in the sedimentation history. The grain size, allothigenic particles, carbonate minerals, organic matter and isotopic composition of carbon and oxygen are the most informative indicators. Grain size variations and the ratio between allothigenic and carbonate components reflect changes in the Lake’s depth and clastic material supply, which, in turn, is associated with humidity. Organic matter parameters (TOC, δ13Corg, C/N ratio) can be considered as indicators of climate-sensitive changes in bioproductivity of the sedimentation basin. They also reflect the ratio of exogenous and endogenous organic matter in the sedimentary environment. The isotopic composition of carbon and oxygen (δ13Ccarb, δ18Ocarb) in sedimentary carbonates is an informative indicator of lithological zones and climatic events of the Holocene due to its sensitivity to changes in biomass, temperature fluctuations, and fresh water inflow. The paramagnetic component k_para was used as an indicator of the allothigenic material input into the lake basin for the first time in this region. Conclusions. The granulometric, mineral, and chemical composition, as well as the magnetic properties of Lake Bannoe sediments reflect the history of Lake sedimentation in the Southern Urals, which agrees mainly with the climate stages of the Holocene.

Evidence of Middle Holocene landslide-generated tsunamis recorded in lake sediments from Saqqaq, West Greenland

Abstract. The Vaigat strait (Sullorsuaq) in West Greenland is well known for its susceptibility to landslides and historical landslide-generated tsunamis. Recent mapping of the seabed in the Vaigat strait has revealed several prehistoric giga-scale (volumes of 109 m3) tsunamigenic landslides. However, the timing of these giga-scale tsunamis is largely unconstrained, but they are assumed to have occurred after the last deglaciation. Here, we report on lake sediment core records from four coastal lakes located between 19 and 91 m above sea level (a.s.l.) on the Saqqaq foreland at the eastern end of the Vaigat strait. We use a multiproxy approach including X-ray fluorescence (XRF) and magnetic susceptibility core scanning along with a screening for marine diatoms to identify at least two tsunami deposits in two of the four sediment cores. Radiocarbon dating of aquatic macrofossils and bulk samples suggest that the tsunami events occurred at ca. 7.6 and 7.3 ka cal BP. Using a previously published relative sea level curve from Vaskebugt, Arveprinsen Ejland (Alluttoq), located 40 km southeast of Saqqaq, we infer wave runup heights of ca. 41–66 and 45–70 m, respectively, for the two tsunami events. These runup heights from prehistoric tsunamis are 1 to 2 orders of magnitude higher than the historic landslide-tsunami runup heights at Saqqaq which only reached an elevation of ca. 3 m in November 2000. While we found deposits from two tsunami events in the lake sediments, landforms from at least nine giga-scale landslides are present on the seafloor of Vaigat. We infer that these deposits probably represent the two most recent tsunamis identified in the Vaigat strait and that the older tsunamis must have happened between the last deglaciation and the oldest sediment in the lakes, i.e., between ca. 10.0 and 8.5 ka cal BP.

PALAEOECOLOGICAL SITUATION IN PRE-DELTA AREA OF THE NORTH CASPIAN SEA DURING THE HOLOCENE

Palaeoecoligical reconstructions of predelta area of the North Caspian Sea were based on the multidisciplinary study of the core from the Rybachya borehole containing the Holocene deposits. Geochemical, grain size, mollusk fauna, diatom and ostracod analyses were performed, and the radiocarbon dating was carried out. The structure of deposits reflects palaeogeographic events of different scales including the inception of a palaeoincision in the Lower Khvalynian deposits, accompanied by erosion of the Upper Khvalynian deposits; its development during the Mangyshlak regression and gradual filling during the multistage Holocene Neocaspian transgression. The Holocene age of the deposits filling the palaeodepression is confirmed by radiocarbon dates - 8070 ± 110 and 7020 ± 140 cal. BP. The paleontological data indicate the interchange of tranquil and dynamic water regimes and the quasicyclical change in the conditions of the water basin, from brackish to freshwater and to marine during the stage of sedimentation, corresponding to the presentday conditions on the North Caspian shelf.

Iron Age Activity beside the River Dee, Cairngorms

In June 2019, a charcoal-rich pit was identified in an eroding riverbank during a walk-over survey along the River Dee, in the Mar Lodge Estate, Cairngorm Mountains, as part of a wider Mesolithic research project in the area led by researchers from University College Dublin. Subsequent radiocarbon dating of pine charcoal revealed that the pit was used in the earlier first millennium AD, providing the first archaeological evidence for Iron Age activity in this area of the Cairngorm mountains. No artefacts were uncovered, but the archaeobotanical assemblage from the pit provides evidence for the nature of fuel procurement strategies in this area in the Iron Age. The results highlight the difficulty of identifying early prehistoric archaeological activity in mountain environments and the potential for the survival of further later prehistoric evidence in this area of Mar Lodge.

Surface Rupturing Earthquakes of the Greater Caucasus Frontal Thrusts, Azerbaijan

AbstractHere we present the results of the first paleoseismic study of the Kura fold‐thrust belt in Azerbaijan based on field mapping, fault trenching, and Quaternary dating. Convergence at rates of ∼10 mm/yr between the Arabian and Eurasian Plates is largely accommodated by the Kura fold‐thrust belt which stretches between central Azerbaijan and Georgia along the southern front of the Greater Caucasus (45–48°E). Although destructive historic earthquakes are known here, little is known about the active faults responsible for these earthquakes. A paleoseismic trench was excavated across a 2‐m‐high fault scarp near Agsu revealing evidence of two surface rupturing earthquakes. Radiocarbon dating of the faulted sediments limits the earthquake timing to AD 1713–1895 and AD 1872–2003. Allowing for uncertainties in dating, the two events likely correspond to historical destructive M ∼ 7 earthquakes near Shamakhi, Azerbaijan in AD 1668 and 1902. A second trench 60 km west of Agsu was excavated near Goychay also revealing evidence of at least one event that occurred 334–118 BC. Holocene shortening and dip‐slip rates for the Kura fold‐thrust belt are ∼8.0 and 8.5 mm/yr, respectively, based on an uplifted strath terrace west of Agsu. The only known historical devastating (M > ∼7) earthquakes in the Kura region, west of Shamakhi, occurred in 1139 and possibly 1668. The lack of reported historical ruptures from the past 4–8 centuries in the Kura, in contrast with the numerous recorded destructive earthquakes in Shamakhi, suggests that the Kura fold‐thrust belt may have accumulated sufficient strain to produce a M > 7.7 earthquake.

Prehistoric and Early Medieval Settlement Features at Ravelrig Road and Newmills Road, Balerno, City of Edinburgh

Evaluation and excavation works in advance of housing development at two sites on Ravelrig Road and Newmills Road, Balerno, City of Edinburgh, revealed significant archaeological features evidencing multi-phase settlement. At Ravelrig Road, two groups of pits were dated to the Early and Middle to Late Neolithic periods with a cluster of Copper Age and Early Bronze Age features that included two possible storage features. At Newmills Road, alongside limited evidence for late prehistoric occupation in the form of pits dating to the last centuries BC and the first centuries AD, the most significant remains were of early medieval date, including a ring-groove representing a putative roundhouse and other features, including a hearth and linear boundary features, generally placed between the 7th and 9th centuries AD according to radiocarbon dating.

Radiocarbon dates from Curaçao’s oldest Archaic site extend earliest island settlement to ca. 5700 cal BP

Due to its proximity to coastal South America and settlement during the early phase of insular Caribbean occupation, Curaçao’s archaeological record offers potential evidence for early overwater exploration and regional interaction. Here, we report new accelerator mass spectrometry (AMS) dates on charcoal from C-1426 at Saliña Sint Marie, an Archaic rockshelter site that extends Curaçao’s occupation back to 5735–5600 cal BP, some 290–850 years earlier than the established settlement chronology. This finding makes the C-1426 rockshelter Curaçao’s earliest known archaeological site and among the oldest in the insular Caribbean. We describe the site and the archaeological context of dating and conclude by considering the implications of Curaçao’s revised occupation chronology for initial Caribbean settlement.

New Evidence of Neolithic Funerary Monuments from the Eastern Margins of the Long Barrows Territory in Central Europe

Late Neolithic long barrows are commonly found throughout Central and Northwestern Europe, within the Funnel Beaker Culture territory. The sites of this Culture are known from Bohemia covering a period between 3900 and 3400 BC. However, long barrows have not been detected in Bohemia for a long time. The main reason is that they are located in areas where they were affected by modern ploughing. A significant contribution to their recognition was the remote sensing of modern fields, especially aerial archaeology. Current research in Bohemia provided new evidence of dozens of long barrows of several types, significantly expanding our knowledge of this phenomenon in the southeastern margins of its distribution. A new type of long barrow has been identified in Bohemia using remote sensing and current excavation data. The characteristic parameters of the long barrows in Bohemia are an east-west orientation with the ceremonial place in the eastern front and the delineation of the perimeter by a palisade trough or a ditch. The mounds can be divided into at least two structural and chronological forms. The first is the narrow and sometimes extremely long mound with perimeter defined by a palisade trough dating to the 3900–3800 BC. The second type of barrow is enclosed by a trapezoidal ditch. Based on radiocarbon dating, these structures were constructed during the 3700–3600 BC. This type of monument is currently known exclusively from Bohemia.

First record of insects from the oldest and older Dryas of Altai (Russia). Coleoptera assemblages from Lebed River

Subfossil remains of insects found in the Lebed site (52.25220°N, 87.15692°E) located on the Lebed River, Altai Republic are recorded. The calibrated radiocarbon dates for two layers of these deposits were 16,461–17,056 cal BP, and 13,520–14,077 cal BP, which correspond to the oldest and older Dryas (Late Pleistocene). Insect assemblages of these deposits are mainly represented by Coleoptera, which are noteworthy there for high taxonomic and ecological diversity and include several endemic and relic species. At least 120 beetle species from 17 families have been found altogether, of them, 37 species are recorded for the Pleistocene deposits of Western Siberia for the first time. Three families, Carabidae, Staphylinidae and Curculionidae are most abundantly represented in the examined Lebed site. Ecologically, this beetle assemblage is dominated by species that are currently confined to the taiga belt and alpine meadows of the Altai Mountains; aquatic and near-water species are also well represented. The studied assemblages are rather different from the previously studied Pleistocene insect fauna in the south of the West Siberian Plain. The taxonomic and ecological compositions of the beetle fauna of Lebed site suggest its existence under humid palaeoclimate that was significantly colder than modern climate in this area.

Mediterranean Early Iron Age chronology: assessing radiocarbon dates from a stratified Geometric period deposit at Zagora (Andros), Greece

In this article, the authors present an analysis of radiocarbon dates from a stratified deposit at the Greek Geometric period settlement of Zagora on the island of Andros, which are among the few absolute dates measured from the period in Greece. The dates assigned to Greek Geometric ceramics are based on historical and literary evidence and are found to contradict absolute dates from the central Mediterranean which suggest that the traditional dates are too young. The results indicate the final period at Zagora, the Late Geometric, should be seen as starting at least a century earlier than the traditional date of 760 BC.

The dynamics of fishing villages along the South Atlantic Coast of North America (ca. 5000–3000 years BP)

We present new chronologies that inform the timing and tempo of shell ring and shell mound construction on the South Atlantic Bight. Our project combines recently acquired dates with legacy radiocarbon dates from over 25 rings and mounds to provide a higher-resolution chronology regarding the occupation and formation of this larger landscape of the earliest fishing villages along the East Coast of the United States. We resolve the ordering and timing of occupation of these rings and mounds through Bayesian statistical modeling. These new models historicize and contextualize these shell rings in ways previously impossible. Specifically, our new chronologies of these villages indicate that the earliest villages were established prior to the invention of pottery. The early period of village establishment evidences isolated village rings, whereas later periods seem to have more villages, but these appear to have been relocated to other areas and/or islands over time. Shell mounds are fewer in number, are spread throughout the time period, and may represent special purpose sites compared to shell-rings. Once villages spread, they quickly adopted new technologies (i.e., pottery) and created new institutions and practiced village relocation, which allowed this way of life to persist for more than a thousand years.

A discussion on carbon and oxygen isotopes of secondary carbonates in loess-paleosol sequences

Although carbon and oxygen isotopic compositions of carbonates are valuable for Quaternary climate reconstruction due to their sensitivity to paleoclimate changes, a comprehensive understanding regarding the formation, factors influencing isotopic variations, and age uncertainties of secondary carbonates in loess deposits remains elusive. This study investigates the microstructure and stable isotopes of secondary carbonates, specifically calcified root cells (CRC) and needle-fiber calcite (NFC), found within the loess deposits of the last glacial period in the northwestern region of the Chinese Loess Plateau. The average δ13C values of soil total organic matter, CRC, NFC, and total inorganic carbonates in the YuanBao sections are −22.1‰, −14.9‰, −7.0‰, −4.6‰, respectively. Radiocarbon dating results reveal that both CRC and NFC were not of synsedimentary origin. The pronounced negativity of the carbon isotopic composition and the microstructures offer insights that CRC formation is closely tied to C3 plants. The synchronous depletion of δ13CCRC and δ18OCRC values during the transition period from the last glacial to the Holocene, underscores the sensitivity of isotopic composition of CRC to local environmental changes, making it a potential candidate for paleo-climate studies. Additionally, CRC formed during the glacial period provides a close approximation to the true sedimentation age. The radiocarbon dating of NFC highlights a significant fluctuation in carbon source translocation depth, resulting in a pronounced temporal and spatial decoupling between NFC formation and the surrounding deposits. Consequently, values of δ13CNFC and δ18ONFC seem to exhibit no significant trend across the limited depth range in this research. We propose that, when using NFC for paleoclimate reconstruction, careful consideration of variations in translocation depths of carbon sources is imperative to prevent misestimations. NFC could potentially be more fitting for broader temporal-scale paleoclimate reconstructions rather than high-resolution investigations.

Patterns of glacio‐isostatic adjustment in mainland Scotland: new data from western central Scotland, proximal to the zone of maximum rebound

The results of geomorphological mapping and survey of Lateglacial and Holocene displaced shorelines in the Clyde estuary and around Loch Lomond, western central Scotland are described. On the basis of morphology, sedimentology, altitude and radiocarbon dating, four discrete shorelines are identified and are correlated with previously identified Scottish displaced shorelines. The shoreline formerly referred to as the Main Postglacial Shoreline is renamed the Menteith Shoreline. This body of data, combined with data on displaced shorelines for Scotland as a whole has been analysed using Gaussian quadratic trend surface analysis in order to determine the centre of glacio‐isostatic displacement for each shoreline. These Gaussian models of palaeo‐relative sea‐level suggest that the zone of greatest displacement lay NNW of Loch Lomond in the Lateglacial then moved SSE to the region of Loch Lomond during the Holocene and the Clyde in the Late Holocene. The factors responsible for the movement of the zone of greatest uplift are discussed, including temporal variations in the ice‐sheet thickness, variations in water load in the adjacent sea‐lochs and neotectonic processes. Comparison is made with glacial isostatic adjustment (GIA) models. A sensitivity analysis has been carried out on the use of Gaussian trend surface analysis glacio‐isostatic modelling and this is included in the research evaluation, and reported in full in the Supporting Information files, along with the raw data used throughout this study.