I discuss here a series of radiocarbon dates from sites of the earliest phase of the Linearbandkeramik (LBK) culture. The samples were collected during excavations directed by Prof. Jens Lüning (Frankfurt am Main) between 1979 and 1987. The samples were mainly charcoal, including cereals and food remains, but bones and potsherds containing organic temper were also included in the study. Although the results on cereal, bone and food remains were consistent, almost all differed from those measured on charred wood. From a series of dates measured by accelerator mass spectrometry (AMS) on organic temper in potsherds, variable amounts of sample contamination were observed, probably deriving from the natural organic components of the clay used in the ceramic production. By critically evaluating 14C dates, individual activities on the sites were dated as accurately as possible. A chronological framework could then be established for the earliest phase of the LBK culture. The dating results provided information on taphonomic processes.

The chief objective of this paper is to improve our understanding of the Neolithic in Eastern Hungary using absolute chronological data. To accomplish this we calibrated new measurements as well as previously published dates. The up-to-date, standardized evaluation of 261 calibrated measurements showed temporal overlaps between archaeological cultures defined on the basis of ceramic styles. The increasing number of dates suggest that the Neolithic period began at the turn of the 6th and 7th millennia bc and lasted for ca. 1500 yr in the present area of the Great Hungarian Plain (Alföld). Further research should be aimed at complementing the current data set with dates from western Hungary and establishing additional correlations among stratigraphic, typological and radiocarbon dates.

To study the transition from the Paleolithic to the Neolithic period and its duration, samples of charcoal, bone, flowstone and shells excavated from Bailiandong and Miaoyan caves, Guangxi Zhuang autonomous region, South China were dated using the Peking University AMS facility and liquid scintillation counter. The remains excavated from these sites show typical characteristics of the transition from the Paleolithic to the Neolithic. Radiocarbon dating results show a rapid transition from ca. 20 to 10 ka bp.

We show how 14C dating may be combined with palynological and paleogeographical research to correlate human occupation history with environmental change, focusing on archaeological sites in the Dvina–Lovat River region of Russia. Cultures in this region range from Early Neolithic to the Middle Ages, ca. 5500 bc–ad 100, based on calibrated 14C ages. The dynamics of water basins in the region, related to climatic change, are one cause of population migration.

During the 1989–1994 renovation of the Zagreb Town Museum, it became obvious that the area was inhabited in prehistoric times. We 14C dated 40 samples to determine various settlement periods. The ages of the samples span a much longer time than expected, from the Early Iron Age (Hallstatt period) to the 19th century ad. 14C dates on charcoal samples placed the remains of dwelling pits in the Hallstatt period, 8th to 4th century bc. A late La Tène settlement dated between the 4th century bc and the 2nd century ad. Medieval fortifications were identified in the western part of the complex, consisting of a well-preserved wooden structure used for construction of the royal castrum. 14C measurements on wooden planks and posts date the construction of the fortification between the 13th and 15th centuries ad and branches, beams, and tools found below the basement of the Convent of St. Clare span the 16th to the 19th century ad.

Biblical and secular data seem to tell entirely different stories about Near Eastern history prior to the first millennium bc. Most modern critical scholars in Bible-related fields regard this as proof of the nonhistoricity of the premonarchical biblical narrative. However, the incongruity between biblical and secular data seems also to be explainable by the postulate that exactly 1000 yr were accidentally dropped from traditional biblical chronology just prior to the first millennium bc. I evaluate this postulate relative to extra-biblical data for the exodus, Joseph's famine and Lot's observation that the Jordan valley was “well watered” in his day. The repeated success of this postulate in integrating much archaeological, historical and geophysical data with the biblical narrative offers support for the historicity of the premonarchical biblical narrative. Biblical chronology, when corrected by the restoration of the lost 1000 yr, promises to reduce present uncertainties in secular historical chronologies in the 3rd and 4th millennia bc by at least an order of magnitude.

I attempted to separate smoke-derived carbon from carbon derived from clay by variable-temperature burning. First, using liquid scintillation counting (LSC) and accelerator mass spectrometry (AMS), I dated experimental potsherds containing these two sources of carbon. I used the same techniques to date archaeological samples. The results on archaeological sherds confirm the difficulty of establishing a standard procedure for pottery dating. Nevertheless, reliable dates on smoke-blackened potsherds are potentially obtainable with AMS dating of thin lamellas in the sherd surface following adequate NaOH treatment.

We present the results of 18 radiocarbon determinations on the carbonate fraction of tooth enamel prepared from nine separate teeth. The known ages of the teeth vary from 11 to >200 ka bp, and are from three sites. The sample preparation procedures varied somewhat, but were broadly based on procedures found to give satisfactory results on carbon stable isotope measurements. All the 14C dates obtained are too young, by an equivalent contamination of ca. 6% Modern (pMC). This value is fairly consistent despite variations in sample preparation. We discuss the implications for using enamel as a possible alternative to bone when insufficient collagen is available.

Archaeological sites on sandy soils often suffer from dislocation of artifacts and datable materials. Because stratigraphy and context lose their meaning in such cases, all 14C dates in this study were put in a dispersion diagram regardless of the sample origin. We drew conclusions about the chronology of the site by comparing this diagram with archaeological analysis of the artifacts and the evolution of the landscape. The dating series, as well as the archaeological analysis, suggest several occupation phases. In general, the archaeological chronology agrees with the 14C dates, although the two can be equated only with caution.

We report here progress on our technique for 14C dating pictographs. We use low-temperature oxygen plasmas coupled with high-vacuum techniques to selectively remove carbon-containing material in the paints without contamination from rock substrates or accretions. We dated >16 pictograph samples that generally agree with ages expected on the basis of archaeological inference. We have shown that carbonate and calcium oxalate decomposition does not occur during our procedure; little mass fractionation is produced. We also used the technique on samples of known 14C activity. In each case our results agree with previously determined ages of archaeological charcoal samples. Two samples of the standard Third International Radiocarbon Intercomparison wood yielded ages in near accord with the accepted value. We used 14C-free samples to establish that the method and apparatus do not have a significant live carbon background. Each of these determinations supports our conclusion that the technique has the potential of producing accurate and reliable ages. However, background organic material in the basal rocks and accretions can be troublesome, often completely negating the dates obtained.

The chemical composition of wood from archaeological sites differs from that of modern wood. The chemical changes depend on the microenvironment of the surrounding matrix more than the time of preservation. Chemical treatment of decomposed wood results in a great loss of initial material. The degree of wood decomposition should be taken into account in the preparation of samples for 14C dating. The main fraction of archaeological decomposed wood is a degraded lignin, with most cellulose totally decomposed. Nevertheless, decomposed wood can be a reliable material for 14C dating archaeological sites. Loss of material through sample preparation can be reduced by using fairly weak concentrations of chemical reagents without influencing the reliability of the dates.

A series of 14C determinations have been obtained on hair samples principally from Holocene contexts that have been variously pretreated to examine different means of removing potential contamination. SEM photomicrographs have documented hair surfaces before and after different pretreatments. Amino-acid composition, C/N ratios and δ13C values have been obtained to biochemically characterize these samples and provide baseline data for future comparisons with less well-preserved samples. Our data support the view that appropriately pretreated hair samples can provide accurate 14C age determinations.

With the advent of AMS radiocarbon dating of very small samples, a much greater opportunity now exists for research into specialized materials. Investigations of the proteins of bone and teeth for archaeological purposes suggest that much more information might be obtained by appropriate study of individual proteins in these tissues. Although present research seems limited to 14C dating, racemization and dietary selection, conditions of the environment during preservation and some of the physiological events during life are likely to be discernible through further studies.

We established a database of 14C dates from archaeological sites of the Central Andes region of Peru, Ecuador and Bolivia on an IBM PC-compatible microcomputer running on an MS-DOS operating system using software package dBASE IV, version 1.1. Relevant data are stored in three DBF-type database files. The file ANDY.DBF contains information on dates and samples; REFERENC.DBF contains references to relevant publications and CALAND.DBF contains calibrated dates. The total number of records of the ANDY database slightly exceeds 2650.

The Swedish Time Scale (STS) is a ca. 13,300-yr-long varve chronology that has been established for the Swedish east coast from >1000 overlapping clay-varve diagrams. We describe the present state of the STS and illustrate the application of this worldwide unique varve chronology for AMS radiocarbon measurements. The results are compared to other 14C-dated calendar-year chronologies: dendrochronology, laminated lake sediments and U/Th. Our data set agrees with the oldest part of the dendrochronological calibration curve, and with AMS 14C-dated lake lamination data and U/Th on corals down to ca. 12 ka calendar years bp. Further back in time, the AMS-dated part of the STS partly compares well with lake lamination chronologies and shows that the difference between 14C and calendar years decreases rapidly between 12,600 and 12,800 calendar years bp. Such a development seems to contrast with U/Th measurements on corals. We suggest that the cause for the divergence among three supposed calendar-year chronologies lies in the fact that the data points on the marine 14C-U/Th curve are more widely spaced in time than the tightly grouped set of terrestrial AMS 14C dates, and thus are not able to reflect short-term changes in atmospheric 14C. Therefore, we argue that the use of the pre-Holocene part of the calibration program is premature and inadvisable.

Dendrochronological studies are being carried out on two conifer species in the Stanley River area of western Tasmania. The chronology for Huon pine (Lagarostrobos franklinii), with living trees up to 1400 yr old, extends back to 571 bc. Living celery-top pine (Phyllocladus aspleniifolius) trees are up to 500 yr old. Apart from living or recently felled trees, sections have been taken from 350 subfossil logs preserved in floodplain sediments. They range in age from >38 ka to modern, with good coverage for the periods 9–3.5 ka and from 2.5 ka to the present. We report here on 14C measurements of decadal samples from three early Holocene logs, between 10 and 9 ka bp, providing short (ca. 300-yr) records of atmospheric 14C variations when plotted against ring numbers. The southern hemisphere data from Tasmania can be compared and wiggle-matched with published 14C calibration curves from German oak and pine. One set of measurements covers the period, ca. 9280–8990 cal bp, overlapping the link between the Hohenheim “Main 9” and middle Holocene master oak chronologies. The other sets of measurements from Tasmania coincide; they span the period, ca. 9840–9480 cal bp, overlapping the end of the German Preboreal pine and the beginning of the oak chronologies. Our measurements confirm that this part of the calibration curve is a gently sloping 14C-age plateau (ca. 8900–8700 bp, between 10,000 and 9500 cal bp), and suggest interhemispheric 14C differences close to zero.

We made accelerator mass spectrometry (AMS) 14C measurements on terrestrial macrofossils from the Late Pleistocene/Holocene of the annually laminated sediments of Lake Suigetsu (central Japan). The AMS 14C dates of terrestrial macrofossils showed agreement between varve counting years and calibrated ages (tree rings and U/Th on coral) in the interval of 10.5 and ca. 11.5 ka cal bp. Beyond 11.5 ka cal bp, the age difference between 14C and varve counting years gradually diminish, contradicting published data on corals dated by U/Th and 14C.

Layers of volcanic ash, or tephra form widespread chronostratigraphic marker horizons which are important because of their distinctive characteristics and rapid deposition over large areas. Absolute dating of prehistoric layers effectively depends upon 14C analysis. We focus here on Icelandic tephra layers at both proximal and distal sites and consider three strategies to obtain age estimates: 1) the conventional dating of individual profiles; 2) high-precision multisample techniques or “wiggle-matching” using stratigraphic sequences of peat; and 3) a combination of routine analyses from multiple sites. The first approach is illustrated by the dating of a peat profile in Scotland containing tephra from the ad 1510 eruption of Hekla. This produced a 14C age compatible with ad 1510, independently derived by geochemical correlation with historically dated Icelandic deposits. In addition, the ca. 2100 bp date for the Glen Garry tephra in Scotland, determined by a series of dates on a peat profile in Caithness, is supported by its stratigraphic position within 14C dated profiles in Sutherland, and may be applied over a very large area of Scotland. More precise dates for individual tephras may be produced by “wiggle-matching”, although this approach could be biased by changes in peat-bog stratigraphy close to the position of the tephra fall. As appropriate sites for “wiggle-match” exercises may be found only for a few Icelandic tephras, we also consider the results of a spatial approach to 14C dating tephra layers. We combined dates on peat underlying the same layer at several sites to estimate the age of the tephra: 3826 ± 12 bp for the Hekla-4 tephra and 2879 ± 34 bp for the Hekla-3 tephra. This approach is effective in terms of cost, the need for widespread applicability to Icelandic tephra stratigraphy and the production of ages of a useful resolution. We stress the need for accurate identification of tephra deposits without which the conclusions drawn from subsequent 14C dating will be fundamentally flawed.

The calibration of radiocarbon dates on marine materials involves a global marine calibration with regional corrections. Data from well-associated marine and terrestrial materials in archaeological artifacts from northern Chile indicated that the calibration is valid for the period ad 200–900 and suggest that coastal upwelling intensities during that period were similar to those of the early 20th century.

The long 14C chronologies currently used as calibration curves combine results from wood that grew in the western United States, the British Isles and Germany. Although these results show few significant differences in the 14C content of contemporaneous wood when averaged over the length of the chronology (i.e., the means of overlapping sections of chronology are the same), closer examination shows considerable variability. Separating the sections of chronology according to the provenance of the wood used for calibration reveals patterns that suggest small but finite differences in the 14C content of wood from different locations. We conclude that there is some evidence that German and American wood give dates older by between 20 and 40 yr from those of Irish oak for some periods. Additionally we suggest that the shift of the Belfast 1986 calibration data by ca. 18 yr toward older dates may not be valid and that the resultant offset between the Belfast 1986 and Seattle 1993 data shows a small but real difference in the 14C content of contemporaneous American, German and Irish wood. Intralaboratory measurements made in Belfast on contemporaneous German and Irish oak, and bristlecone pine and Irish oak, give offsets of 39 and 41 yr, respectively, with the Irish oak dating younger. Previous studies, in which sample pairs of American and English and French wood were processed in the same laboratory, also showed American wood to be slightly depleted in 14C. None of the findings of this study would significantly alter calibrated 14C dates.