Two floating tree-ring chronologies were developed from oak timbers recovered during salvage excavations of a pre-Roman wharf in Este, a prominent center of the Veneti people, who lived in northeastern Italy during the Iron Age. Wiggle-match radiocarbon dating shows that one chronology spans the 10th and 9th centuries cal BC, and that the waterfront was probably built ∼800 cal BC. The second chronology apparently spans most of the 7th century cal BC, and is associated with a phase of construction about 2 centuries after the first. One of the samples gave what appeared to be anomalous 14C results that may best be explained as evidence of a short-term fluctuation in atmospheric 14C level, which can be seen in short-lived samples but is not apparent in the decadal or bidecadal calibration data. Both chronologies cover periods for which there are no other tree-ring chronologies in this region, and could become key to refining the local Iron Age chronology.

During the 1st millennium AD, a fundamental set of changes in ship design, building methods, and sequence of construction took place in the Mediterranean. This process is known as the “Transition in Construction.” Before the Transition, ship hull design was based longitudinally on the ship's strakes (“shell-first”). By about the mid-1st millennium AD, the concept and construction of ship hulls had changed and were based on the ship's frames (“frame-based”). The Transition was a complex, nonlinear evolution. High-precision dating of the construction and service period of ships built during the 1st millennium is essential for elucidating the Transition process. Such dating precision is possible using radiocarbon wiggle-matching and Bayesian analysis techniques. The following study uses these techniques to determine the construction, launch, and final voyage (wrecking) dates of Dor 2001/1, a Byzantine shipwreck from northern Israel that was built based on frames. The results indicate that Dor 2001/1 was likely constructed and launched in the first third of the 6th century AD and was wrecked no later than AD 540. This is one of the earliest frame-based ships found in the Mediterranean so far. Dor 2001/1 is therefore an important shipwreck in understanding the Transition, since it provides evidence that frame-based hulls were already being built by the mid-1st millennium AD, about 500 yr earlier than has been commonly accepted.

Charred plant materials found in archaeological contexts are usually considered the most reliable remains for radiocarbon dating. Usually, seeds and fruits are preferred to wood fragments because their short lifecycle reduces the range of uncertainty of the 14C measurement. A selection of short-lived samples, mainly from barley and wheat, from the Late Roman site of Faragola (SE Italy) were 14C dated; however, the 14C dates obtained were not always consistent with the chronology provided by other archaeological evidence. A careful analysis of all the macrobotanical remains found in each of the dated contexts provides insight into the origin of the plant material, helping to distinguish between in situ and non-in situ material. The 14C dates are reconsidered in the context of findings and the kind of material selected for dating. Using the archaeological context, a Bayesian model was employed to reduce the range of the calibrated date and thereby refine the chronology of the site on an absolute basis.

The radiocarbon dating method was applied to the study of Japanese traditional wooden buildings. The traditional Japanese architecture studied includes the Main Hall of Banna-ji Temple (Buddhist building), Sekisui-in of Kozan-ji Temple (noble house), Hakogi-ke house (farmhouse), and Kawai-ke house (townhouse). 14C dating proved useful as a research method to better understand the history of these buildings and Japanese architecture as a whole.

This study presents accelerator mass spectrometry (AMS) radiocarbon dates and pollen assemblages of 400-cm core sediments collected from the Karekare Swamp in Rarotonga, Southern Cook Islands, to investigate vegetation changes on the island, in particular those induced by human impacts. Eight 14C dates of charcoal and higher plant fragment samples indicate that the sediments accumulated since ∼6.0 cal kBP, with an apparent interruption of deposition (hiatus) from 130 to 132 cm in depth, corresponding to ∼2.8 to 0.7 cal kBP. The appearance of Chenopodiaceae pollen from upland weeds, and Cucurbitaceae and Vigna pollen grains from cultivated plants suggest that human influence existed in core sediments above 130 cm in depth. The increased abundance of Pandanus pollen and monolate-type fern spores also implies the existence of human activity.

This article presents the pretreatment protocols for wood samples processed at the Oxford Radiocarbon Accelerator Unit (ORAU), including recent implementation of a purification method to α-cellulose for non-routine samples. We examine the long-term reproducibility of measurement on wood samples at ORAU through the >1000 14C determinations made on known-age tree-ring standards processed in each AMS wheel since our present High Voltage Engineering Europa (HVEE) AMS system came on-line in September 2002. A discussion of background measurements is also provided.

The updated chronology of the earliest pottery-containing complexes in Siberia and the Russian Far East is presented herein. The appearance of pottery (i.e. the process of Neolithization) in this vast region of Eurasia is discussed based on a model that represents a simple approximation of calendar ages between key sites as isolines. No clear spatiotemporal patterns for the origin and spread of pottery in northern Asia can be observed because pottery-making (unlike agriculture) could have emerged in different parts of the Old World at various times. Before modeling of pottery dispersal is conducted, careful evaluation of typology and technology of ceramics and stone artifacts should be done, in order to avoid the confusing situation when the results of modeling contradict the basic archaeological information.

This article introduces a method of exploratory analysis of the geographical factors influencing large-scale innovation diffusion, and illustrates its application to the case of early pottery dispersal in the Old World. Regression techniques are used to identify broad-scale spatiotemporal trends in the innovation's first occurrence, and regression residuals are then analyzed to identify geographical variation (climate, biomes) that may have influenced local rates of diffusion. The boundaries between the modeled diffusion zones segregate the western half of the map into a Eurasian hunter-gatherer pottery-using zone affiliated by cultural descent to the Siberian center of innovation, and a lower-latitude farming and pastoralist zone affiliated by cultural descent to the north African center of innovation. However, the correlation coefficients suggest that this baseline model has limited explanatory power, with geographical patterning in the residuals indicating that habitat also greatly affected rates of spread of the new technology. Earlier-than-predicted ages for early pottery tend to occur in locations with mean annual temperature in the range approximately 0–15°. This favorable temperature range typically includes Mediterranean, grassland, and temperate forest biome types, but of these, the Mediterranean and the temperate deciduous forest biomes are the only ones on which regression residuals indicate earlier-than-predicted first observed pottery dates.

A case study of the Neolithic comb ceramic site Pezmog 4 of the Kama culture presents a situation when results of radiocarbon dating change long-existing concepts concerning the development of archaeological events. Until the early 2000s, the chronology of the Kama culture, distributed mainly in the Kama and Vychegda River basins, has been based on comparative-typological analysis. Estimates of the age of this culture changed from the 3rd millennium BC in the 1950s to the 1st half of the 4th millennium BC by the 1990s. Research concerning the Pezmog 4 site in the central Vychegda River basin in 1999–2002 has abruptly changed this chronological understanding. The data obtained put the age of the early stage of Kama culture within the time range 5750–5620 cal BC and allowed us to propose the existence of another way of early pottery distribution in the forest zone of eastern Europe at the beginning of the 6th millennium BC. This innovation probably penetrated from the trans-Ural region.

The dolmen known as Shepsi was accidentally discovered on the Black Sea coast (Tuapse region, Russia). Radiocarbon dates show that the classic trapezoidal construction of the Caucasian dolmens with a port-hole appeared in the region as early as 3250 BC. The distinctive structural characteristic for dolmens of that time was a floor slab laid between the side slabs, which were embedded in the ground. The material complex and 14C dates show that this type of dolmen coexisted with the Novosvobodnaya-type of the Maikop culture, located on the northern slope of the main Caucasus ridge. This leads to a new hypothesis concerning the regional origin and further development of the megalithic structures in the western Caucasus.

The corpus of radiocarbon dates run directly on Pleistocene-age human remains in Eurasia (∼120 values, with ∼80 of them found to be reliable) is analyzed and interpreted. The latest Neanderthals are dated to ∼34,000–30,500 BP (∼38,800–35,400 cal BP). They probably coexisted with the first modern humans at ∼36,200–30,200 BP (∼42,500–32,800 cal BP) in the western and central parts of Europe. The earliest direct 14C dates on modern humans in Eurasia are ∼34,950–33,300 BP (∼40,400–37,800 cal BP). A paucity of 14C dates corresponding to the LGM is evident for Europe, but Asia perhaps had larger populations during this timespan. The main criteria for the selection of bone/tooth material for direct 14C dating as now widely accepted are (1) the collagen yield (generally, 1% or more) and (2) the C:N ratio (within the 2.9–3.4 range).

Human and animal bone collagen from different Steppe Bronze Age cultures, including the Yamnaya, East Manych Catacomb, and Lola cultures, show large variations in δ13C and δ15N values. More positive values of δ13C and δ15N are caused by change in diet and/or a more arid climate. Human bones show reservoir effects caused by aquatic diet components. These effects can be quantified by paired dating of human bone and associated terrestrial samples. Previous research showed reservoir corrections for several cultures of the Eurasian steppes Bronze Age, leading to a revision of the local chronologies. Additional investigations showed that some paired dates do not reveal reservoir effects. Recently, our database was extended significantly with new 13C, l5N, and 14C analyses of the Lola, Krivaya, and Babino cultures. The size of the reservoir offset for the studied cultures is discussed.

An overview will be presented of stable isotope data (δ13C and δ15N) available from animal and human bones from Roman to post-Medieval Belgian sites. The data will be used to assess trends in the human diet and evaluate the possible impact of reservoir effects originating from the consumption of fish derived from marine or freshwater environments. Historical and archaeozoological data demonstrate drastic changes in fish consumption throughout the last 2 millennia and thus suggest that fluctuations through time of the impact of the reservoir effects can be expected. However, the present stable isotope data set does not support this suggestion.

Dietary offsets in radiocarbon dates are becoming increasingly interesting to researchers, not only because of their impact on the reliability of chronologies but also because of the possibilities for extracting further dietary information from the 14C data itself. This is the case with the cemeteries of the Cis-Baikal region being studied as part of the international Baikal-Hokkaido Archaeology Project set up to examine hunter-gatherer cultural dynamics in eastern Asia. Fortunately, to control for a freshwater reservoir offset, we were able to obtain a number of paired terrestrial herbivore and human material for 14C dating. This article tests the correspondence between stable isotope evidence and the offsets seen in 14C values and the implications for the analysis of the 14C measurements as “chronometric dates.” This is an unusually well-documented example of freshwater reservoir offsets, providing an ideal case study to test different approaches to analyzing such offset information. Here, a purely Bayesian approach is compared with the more frequently applied linear regression analysis.

Archaeologists interested in radiocarbon dating shell midden sites express concern regarding the accuracy of shell dates and how such determinations should be interpreted. This article discusses the problem of dating shells from sites in the southeastern United States. New results are presented comparing shell, bone, and soil-charcoal age determinations from the Crystal River site, located along the west-central Gulf Coast of Florida. Crystal River is a large multimound site whose occupants engaged in long-distance exchange throughout eastern North America during the Woodland period (∼1000 BC to AD 1050). In the summer of 2012, test units were excavated in several contexts at the site, including both mounds and occupation areas. Samples were collected for 14C dating, which were then processed at the University of Georgia Center for Applied Isotope Studies. This article focuses on samples from the stratified shell midden, from which it was hoped to construct a local correction for marine shell that could be used to date other contexts. The soil-charcoal and bone collagen from these samples have very similar ages (bone samples ranging from about 100 cal BC to cal AD 530 and soil-charcoal from cal AD 345 to 560); however, the shell samples collected from the same stratigraphic units are significantly older than the terrestrial dates (ranging from 1300 to 390 cal BC). The difference in calibrated ages between organic materials and the shells ranges between 560 to 1140 yr. This phenomenon cannot be explained solely by the marine reservoir effect. It appears that all the shell samples formed in mixed marine (∼50–60%) contexts, as indicated by the stable isotope ratios and the amount of atmospheric carbon remaining in the samples. The age of the shell samples cannot be used to date archaeological events as they are influenced not only by the marine reservoir effect, but also the local hardwater effect, which makes them significantly older.

Previous stable isotope studies of modern and archaeological faunal samples from sites around Lake Mývatn, within the Mývatnssveit region of northeast Iceland, revealed that an overlap existed between the δ15N ranges of terrestrial herbivores and freshwater fish, while freshwater biota displayed δ13C values that were comparable with marine resources. Therefore, within this specific ecosystem, the separation of terrestrial herbivores, freshwater fish, and marine fish as components of human diet is complicated when only δ13C and δ15N are measured. δ34S measurements carried out within a previous study on animal bones from Skútustaoir, an early Viking age settlement on the south side of Lake Mývatn, showed that a clear offset existed between animals deriving their dietary resources from terrestrial, freshwater, and marine reservoirs. The present study focuses on δ13C, δ15N, and δ34S analyses and radiocarbon dating of human bone collagen from remains excavated from a churchyard at Hofstaoir, 5 km west of Lake Mývatn. The results demonstrate that a wide range of δ34S values exist within individuals, a pattern that must be the result of consumption of varying proportions of terrestrial-, freshwater-, and marine-based resources. For that proportion of the population with 14C ages that apparently predate the well-established first human settlement of Iceland (landnám) circa AD 871 ± 2, this has enabled us to explain the reason for these anomalously old ages in terms of marine and/or freshwater 14C reservoir effects.

Riņņukalns is the only known prehistoric shell midden in the eastern Baltic, and is one of the few middens in northern Europe consisting mainly of freshwater mussel shells. Situated on the Salaca River at the outlet of Lake Burtnieks, in northeastern Latvia, the site was originally excavated in the 1870s, and reinvestigated several times over the following decades. A new excavation in 2011 showed that part of the midden remained intact. The new exposure, dated to the later 4th millennium cal BC, yielded rich fishbone and mollusk shell assemblages, herbivore, human and bird bones, and a wide range of artifacts typical of a subsistence economy based on fishing, hunting, and gathering. Human remains from burials excavated in the 1870s were also located in archives. The co-occurrence at Riņņukalns of human remains with a broad range of terrestrial and aquatic food remains provides an ideal setting to study freshwater reservoir effects and other isotopic signals of diet and mobility. The extent of 14C depletion in local freshwater resources is an essential parameter for such studies; on the basis of 14C ages of modern and paleoenvironmental samples, we estimate that the applicable reservoir age in Lake Burtnieks is in the order of 800–900 14C yr.

The Chauvet-Pont d'Arc Cave is one of the most important sites for the study of the earliest manifestations and development of prehistoric art at the beginning of the Upper Paleolithic. Different dating techniques have been performed thus far (AMS 14C, U/Th TIMS, 36Cl dating) to model the chronological framework of this decorated cave. The cave yielded several large charcoal fragments, which enabled the opportunity for obtaining multiple dates; thus, a First Radiocarbon Intercomparison Program (FIP) was initiated in 2004 using three charcoal pieces. The FIP demonstrated that those cross-dated samples belonged to a time period associated with the first human occupation. One of the statistical interests of an intercomparison program is to reduce the uncertainty on the sample age; thus, to further assess the accuracy of the chronological framework, the Second Intercomparison Program (SIP) involving 10 international 14C laboratories was carried out on two pieces of charcoal found inside two hearth structures of the Galerie des Mégacéros. Each laboratory used its own pretreatment and AMS facilities. In total, 21 and 22 measurements were performed, respectively, which yielded consistent results averaging ∼32 ka BP. Two strategies have currently been developed to identify statistical outliers and to deal with them; both lead to quasi-identical calibrated combined densities. Finally, the new results were compared with those of the FIP, leading to the important conclusion that five different samples from at least three different hearth structures give really tightened temporal densities, associated with one short human occupation in the Galerie des Mégacéros.

The chronological framework of European protohistory is mostly a relative chronology based on typology and stratigraphic data. Synchronization of different time periods suffers from a lack of absolute dates; therefore, disagreements between different chronological schemes are difficult to reconcile. An alternative approach was applied in this study to build a more precise and accurate absolute chronology. To the best of our knowledge, we have collected all the published 14C dates for the archaeological sites in the region from the Ebro River (Spain) to the Middle Danube Valley (Austria) for the period 1800–750 BC. The available archaeological information associated with the 14C dates was organized in a database that totaled more than 1600 14C dates. In order to build an accurate and precise chronology, quality selection rules have been applied to the 14C dates based on both archaeological context and analytical quality. Using the OxCal software and Bayesian analysis, several 14C time sequences were created following the archaeological data and different possible scenarios were tested in northern Italy and southern France.