Palaeolithic radiocarbon chronology: quantifying our confidence beyond two half-lives

It is now three decades since Waterbolk introduced evaluation criteria to ¹⁴C chronology. Despite this, and other subsequent attempts to introduce quality control in the use of ¹⁴C data, no systematic procedure has been adopted by the archaeological community. As a result, our databases may be significantly weakened by questionable dates and/or questionable associations between dated samples and the archaeological phenomena they are intended to represent. As the use of chronometric data in general becomes more ambitious, we must pause and assess how reliable these data are. Here, we forward a set of evaluation criteria which take into account archaeological (e.g. associational, stratigraphic) and chronometric (e.g. pre-treatment and measurement) criteria. We intend to use such criteria to evaluate a large ¹⁴C dataset we have assembled to investigate Late Glacial settlement in Europe, the Near East and North Africa, supported by the Leverhulme Trust. We suggest that the procedure presented here may at least form the basis of the development of more rigorous, scientific use of ¹⁴C dates.     

A radiocarbon chronology for the complete Middle to Upper Palaeolithic transitional sequence of Les Cottés (France)

The Middle to Upper Palaeolithic transition is the key period for our understanding of Neanderthal and modern human interactions in Europe. The site of Les Cottés in south-west France is one of the rare sites with a complete and well defined sequence covering this transition period. We undertook an extensive radiocarbon dating program on mammal bone which allows us to propose a chronological framework of five distinct phases dating from the Mousterian to the Early Aurignacian at this site. We found that the Mousterian and Châtelperronian industries are separated from the overlying Protoaurignacian by a gap of approximately 1000 calendar years. Based on a comparison with Upper Paleolithic sites in Europe we see an overlap in the ages of Châtelperronian industries and Aurignacian lithic assemblages, which are usually associated with Anatomical Modern Humans, which is consistent with an acculturation at distance model for these late Neanderthals. The Proto and Early Aurignacian appear contemporaneous indicating that this transition was rapid in this region. Anatomically Modern Humans are present at the site of Les Cottés at least at 39,500 cal BP roughly coincident with the onset of the cold phase Heinrich 4.     

Bayesian modelling of an absolute chronology for Egypt's 18th Dynasty by astrophysical and radiocarbon methods

Only a few astrophysical points and synchronisms listed in texts provide anchor points for the absolute chronology of Ancient Egypt. At first we will show how we can re-calculate some of these anchor points by using Sothic dating based on the arcus visionis method, and modelling lunar dates using a Bayesian approach. Then, we will discuss two radiocarbon studies carried out on short-lived Egyptian materials held at the Louvre Museum that could be attributed to particular reigns or other precise periods. Using a Bayesian approach, these dates were combined with the known order of succession and the lengths of reigns. Sothic and lunar dates were integrated as priors in the model. This approach has led to a new proposal for the absolute chronology of Egypt's 18th Dynasty.     

Holocene marine ingressions in the coastal zone of the pomeranian bay based on radiocarbon assays

In recent years, a team at the Geology and Paleogeography Unit, Marine Sciences Institute, University of Szczecin, has been performing geological, geochronological and paleogeographic surveys in (i) the Szczecin Lagoon and Świna Gate Sandbar and (ii) the estuary section of the Rega river valley near Mrzeżyno. These studies have helped to examine and identify not only the distribution of fossil marine sediments but also their lithological and sedimentological characteristics. The age of marine ingressions and regressions in the coastal zone of the Pomeranian Bay were determined using approximately 170 radiocarbon assays.     

U-series and radiocarbon dates on mollusc shells from the uppermost layer of the archaeological site of KHB-1, Ra's al Khabbah,Oman

The archaeological site of KHB-1, Oman, has been investigated in order to improve the chronological knowledge of the site, which is dated to the beginning of the fourth millennium B.C. on the basis of the archaeological context. Mollusc shells of the genus Anadara, coming from the uppermost layers of the site, have been dated using two different methods, radiocarbon and U-series technique. The results of the two techniques date the last occupational phase of the site from the end of the fourth millennium B.C. to the beginning of the third millennium B.C.     

An island-wide assessment of the chronology of settlement and land use on Rapa Nui (Easter Island) based on radiocarbon data

The archaeological landscape on Rapa Nui (Easter Island) contains a palimpsest of surface archaeological features reflecting a long history of settlement and land use. The popular narrative of societal collapse prior to European contact relies on chronometric data from the late pre-European contact period and also cites major settlement shifts as evidence for societal collapse and socio-political reorganization. This paper explores the archaeological evidence for proposed changes in settlement by assessing the spatial and temporal distribution of radiocarbon determinations collected from archaeological and landscape contexts. A corpus of over 300 determinations is placed into an island-wide GIS database and analysed. The results of this study suggest that Rapa Nui settlement and land use exhibit continuity rather than punctuated, detrimental change during the late pre-European contact period.     

A third millennium kiln from the Oman Peninsula

In 1970–71 a pottery kiln was excavated by a Danish expedition led by K. Frifelt at Hili in what is now part of Al Ain in the United Arab Emirates. The kiln and its contents, which date from the second half of the third millennium BC, are important additions to our knowledge of prehistoric ceramic production in the Oman Peninsula.     

Sample preparation for accelerator-based radiocarbon dating

Although several efficient sample preparation methods have been devised for conventional radiocarbon dating, the advent of the accelerator mass spectrometer (AMS) dating technique with its much smaller sample requirement and different counting method has meant that new preparation routes have had to be developed. Techniques used for the Oxford AMS system are described in this paper.     

A comparison of the treatment of errors in radiocarbon dating calibration methods

The application of radiocarbon dating to archaeological samples generally requires calibration of ¹⁴C dates to calendar ages and interpretation of dating errors. In this paper, four recent methods of age calibration are assessed, particularly with regard to their quality of error treatment. Recent experimental research has suggested that commonly quoted errors on “raw” ¹⁴C dates may require enlargement to more realistic levels, which, when incorporated in the calibration schemes, produce a considerable increase in the size of the typical calibrated interval. A general decrease in the sensitivity of ¹⁴C dating using single, “normal precision” dates is implied. Thus typical calibrated age intervals range from 300 to 1300 years (approximate 95% confidence level), with little improvement resulting if “high precision” calibration systems are used to correct “normal precision” dates. Of the four methods considered here, that proposed by Neftel is found to provide the most objective, flexible, comprehensive and “easy to use” scheme. This method is particularly recommended for its treatment of errors both on the dates to be calibrated and on the calibration curve itself.     

Luminescence and radiocarbon dating as tools for the recognition of extraterrestrial impacts

Extraterrestrial events and the extraterrestrial origin of both material and impact forms were recognized in the Morasko, Kaali and Przełazy shallow geological profiles by means of luminescence and radiocarbon dating as well as the frequency of magnetic spherules. The obtained results provide a promising tool for proving theat extraterrestrial events affected characteristic lithological and morphological environmental features.     

“The Good,the Bad,and the Ugly”: evaluating the radiocarbon chronology of the middle and late Upper Paleolithic in the Enisei River valley,south-central Siberia

The ¹⁴C record for the Upper Paleolithic in Siberia has remained largely unevaluated and includes good, bad, and ugly dates. Too often researchers accept either all published dates or only those dates that tend to support proposed chronological hypotheses, regardless of sample quality and association. This article systematically evaluates all published ¹⁴C dates (including several newly obtained AMS dates) from middle and late Upper Paleolithic sites in the Enisei River valley of south-central Siberia to establish a reliable chronology for the region and address the tempo of modern human dispersals in Siberia during late Pleistocene times. The revised chronology indicates humans were present before and after the Last Glacial Maximum, but absent during this climatic event. Results also suggest that human population in the region may have increased during the Oldest Dryas.     

A comprehensive numerical chronology for the pre-Columbian cultures of the Palpa valleys,south coast of Peru

Before the arrival of the Spaniards in Peru in 1532, many different societies flourished in the coastal desert of southern Peru. Of these, one of the best known is the Nasca culture (living in the area between about 260 cal BC and 640 cal BC.), which created the famous geoglyphs on the desert floor. In this paper we present a numerical chronology for the cultural development in the valleys of Palpa, in the northern part of the Nazca region, which spans the time from the Archaic Period (starting there around 3760 cal BC) to the Late Intermediate Period (terminating with the arrival of the Spaniards in 1532 AD). The chronology is based on more than 150 ¹⁴C samples collected by our project from well-documented archaeological excavations of 17 different sites in and around Palpa. Thanks to the advanced AMS-¹⁴C dating technique, demanding only few milligrams of organic material, we could focus on samples of plants, like beans, corn, or reed, representing single years of growth or use, and also on delicate materials like straw from clay bricks (adobe) and textiles. All single ¹⁴C dates were combined to cultural phases using a Bayesian statistical model, implementing the a priori information of the archaeological contexts, and adopting the relative ceramic chronologies available for this area.     

Gazetteer of small‐scale monuments in prehistoric Hadramawt,Yemen: a radiocarbon chronology from the RASA‐AHSD Project research 1996–2008

This paper provides a new, interpretive gazetteer and chronology of Hadramawt’s highland monuments based on results from archaeological survey and test excavations by the RASA‐AHSD (Roots of Agriculture in southern Arabia‐Arabian Human Social Dynamics) Project. With the exception of a few incidental sightings and an unpublished pipeline survey, the prehistoric record of southern Yemen’s highland plateau has been largely unknown. There are few settlements, so that understanding human landscape history must begin with the numerous small‐scale stone monuments left by mobile people. With examples representing monuments from the fifth, fourth, third and first millennia BC, the corpus of small excavations and radiocarbon dates reported here provides the first guide to the monument types of South Arabian highlands. Monument building began under more moist conditions and appears to have commemorated animal sacrifices long before commemorating mortuary rites and interment. There appears to be a temporal break of 1000 years before the widespread and varied practices of Bronze Age tomb construction, which lasted through the third millennium BC. After another break in monument construction, tombs were reused in the first millennium BC, sometimes with successive ritual visits. The data presented offer new material for the interpretation of the lives and activities of prehistoric pastoralists throughout the Holocene.     

Investigating the likelihood of a reservoir offset in the radiocarbon record for ancient Egypt

Some radiocarbon dates for ancient Egypt have been significantly offset from the established historical chronology (see Bonani et al., 2001). In this paper, short-lived plant species collected in Egypt between 1700 and 1900 AD were used to investigate the possibility that the radiocarbon record had been influenced by reservoir effects. AMS radiocarbon measurements were made on 66 known-age samples, resulting in an average offset from expected values of 19 years. The implications of this minor discrepancy on the likelihood of a reservoir process are discussed, and the agreement of the data with recent models of radiocarbon seasonality is also considered.     

The archaeology of radiocarbon accelerator dating

Accelerator mass spectrometry (AMS) allows radiocarbon dating to be carried out by direct counting of¹⁴C atoms, rather than the conventional counting of radioactive disintegrations. The result is that samples up to 1000 times smaller can be handled. The approach was tested in principle by 1977 and for archaeological operation by 1983. More than 2000 samples per year are now being dated worldwide. The machines can now operate to about ± 80 years or better. Dates older than 40,000 years have not yet been achieved, but the ability to use small samples has already had considerable impact on dating the period 10,000–30,000 years ago. Bone is an ideal material for the new technique, since amino acids can normally be isolated and purified from gram-size samples. Studies of the origins of domestication are aided by the dating of individual grains and seeds. Because small samples can be mobile in the soil, careful sample selection strategies and procedures are required. The full impact of the technique can be assessed only through the rapid and comprehensive publication of archaeological results.     

On some remains of dog (Canis familiaris) from the Mesolithic shell-middens of Muge,Portugal

The dog has a unique relationship with humans. This is demonstrated by the number of breeds that exist today and the important role that dogs play in human society. The archaeological record also shows that this relationship began long ago when groups of hunter–gatherers domesticated the wolf probably in several parts of the globe.