In archaeological dating, the greatest confidence is usually placed upon radiocarbon results of material that can be directly related to a defined archaeological event. Human bone should fulfill this requirement, but bone dates obtained from Pacific sites are often perceived as problematic due to the incorporation of 14C from a range of different reservoirs into the collagen via diet. In this paper, we present new human bone gelatin results for 2 burials from the SAC archaeological site on Watom Island, Papua New Guinea, and investigate the success of calibrating these determinations using dietary corrections obtained from δ34S, δ15N, and δ13C isotopes.

Radiocarbon dating of early Pre-Pottery Neolithic B (PPNB) deposits at the site of Motza, Israel, was achieved by first prescreening many charcoal and bone samples in order to identify those that are in the most suitable state of preservation for dating. For assessing bone preservation, we determined the collagen contents, and by infrared spectroscopy the collagen purity. The collagen samples of the best preserved bones were then further characterized by their C/N ratios and amino acid compositions. Prescreening of the charcoal samples involved monitoring the changes in infrared and Raman spectra during the acid-alkali-acid treatments. In some samples, we noted that the clay content increased with additional alkali treatments. These samples were rejected, as this could result in erroneous dates. No differences were observed in the 14C dates between charcoal and bone collagen samples. The dates range from 10,600–10,100 cal BP, which is consistent with dates for the early PPNB from other sites. This is of much interest in terms of better understanding where and when domestication of animals began in this period, and how agriculture spread throughout the Levant.

Bone and charcoal samples from the Neolithic site of Serra Cicora in the Salento Peninsula (southern Italy) have been dated by accelerator mass spectrometry (AMS). Measurements appear to support other archaeological evidence and have shown that 2 distinct phases of human occupation of the site can be identified: the first occupation in the Early Neolithic and a second occupation in the Middle-Late Neolithic. The results provide new information and are a fundamental contribution to the definition of the absolute chronology of the Middle-Late Neolithic in this part of Europe.

Radioactive nuclides such as radiocarbon can be good tracers for investigating the circulation of underground carbon and water. Volcanic gas can be sampled reliably for 14C analysis and prepared for analysis by accelerator mass spectrometry (AMS). In this paper, we establish a method for the measurement of 14C in volcanic gas, and measure the amounts of 14C in various volcanic gases. Samples of fumarolic gas from some Japanese volcanoes were found to contain 0.5 to 4.2 pMC, while those from White Island in New Zealand contained 2.6 pMC. Dissolved gas from Lake Nyos, Cameroon, contained 0.4 to 4.8 pMC. The data indicate a mixing process between surface carbon and deep carbon.

The Fengxi site is near the Feng River in Shaanxi Province, China. Feng City was the capital of the vassal state of Zhou, and the Zhou people lived in this area until the end of the Western Zhou. Serial samples of charcoal, bone, and charred millet were collected from the site and dated by accelerator mass spectrometry (AMS). A sequence model with 6 phases of the Western Zhou dynasty was constructed and the 14C ages were calibrated with OxCal v 3.9. The results showed that the site was used from 1170–1070 BC until 825–755 BC, and the Conquest of Shang by King Wu most probably occurred during 1060–1000 BC.

After benzene synthesis, radiocarbon dating samples are usually stored for 3–4 weeks before counting to allow an eventual radon contamination to decay to a negligible level. This paper presents a technique that can minimize, and often eliminate, this delay by using a simple single-phototube liquid scintillation counting system, specifically designed for 14C dating. Radon contamination is assessed by pulses of 214Po (a 222Rn decay product, half-life 0.16 μs), identified through pulse-time analysis. For each 214Po pulse, 0.49 beta particle pulses of 214Pb and 214Bi fall in the 14C counting window, and the 214Po pulses are used to correct the 14C count rate. A 14C sample (count rate 11.6 cpm) was measured continuously for 16 days. It was then doped with radon, which increased the first 24-hr count rate in the 14C channel by 3.8 cpm, and the sample was measured for 27 more days. Radon did not measurably affect the 14C-corrected count rate. Counting a sample for 2 min reveals whether it needs storing. If the radon concentration is low, the sample can be measured immediately without degrading accuracy.

Recent osteological analyses of archaeological human skeletal remains from the Ust'-Yurt Plateau, Uzbekistan, provided the opportunity to obtain samples for radiocarbon dating. The results of 18 accelerator mass spectrometry (AMS) dates are presented in this paper and provide the first absolute dates for late prehistoric and early historic archaeological sites in Uzbekistan. The AMS dates suggest that most sites are earlier than have been traditionally thought based on relative dating using artifact typologies.

Accelerator mass spectrometry (AMS) radiocarbon dates of pollen concentrate were obtained from multistage syngenetic ice wedges of cross-sections from the Late Pleistocene Bison site, located along the Lower Kolyma River (68°34'N, 158°34'E), from ∼43,600 to ∼26,200 BP, and 3 AMS 14C dates of pollen concentrate in ice wedges from the Seyaha site cross-section, located on the east coast of the Yamal Peninsula (70°10'N, 72°34'E), from ∼22,400 to ∼25,200 BP. Pollen concentrate samples were prepared using a special pretreatment procedure. Pollen and spores from ice-wedge ice signalize a regional pollen rain. Therefore, 14C-dated extracts of pollen and spores from ice-wedge ice enable an adequate reconstruction and chronology of landscape dynamics on a regional scale. The pollen and spores were well preserved despite numerous redepositions in the penecontemporaneous structure in which they were found. Thus, a comparison with dates on other fractions from the same sample is necessary. The youngest date is the most reliable among the intersample AMS 14C dates from the ice and permafrost sediments.

Total CO2 exposure levels in a naturally enriched site (Lajatico, Italy) were reconstructed using radiocarbon analysis by accelerator mass spectrometry combined with dendrochronological analysis on wood cores extracted from trees grown in the fossil CO2 source proximity. Over 3 decades (1964–1998), the data show a mean CO2 concentration in the atmosphere of 650 ppm, about twice the current concentration in atmosphere, with a maximum around 1980.

We present a Holocene radiocarbon chronology of hunter-gatherer occupation based on contemporaneous samples of charcoal and Mytilus californianus shell recovered from 7 archaeological sites near Bodega Bay, California, USA. A series of 127 14C ages reveals a chronological sequence that spans from 8940–110 cal BP (1 σ). This sequence serves as a foundation for the interpretation of behavioral change along the northern California coast over the last 9000 yr, including the adaptive strategies used by human foragers to colonize and inhabit coastal areas of this region. These 14C ages will also permit us to explore major dimensions of temporal change in Holocene ocean conditions (via marine reservoir corrections) and their potential effect on the resources available to ancient hunter-gatherers.

Archaeological investigations in the Republic of Palau, Micronesia, have produced 409 radiocarbon age determinations from cultural contexts, indicating a range of Palauan occupation from about 3000 yr ago into the modern era. However, these dates are scattered among numerous sources (many difficult to obtain) and are presented in a number of different formats and calibrations. The goal of this paper is to compile a usable, systematic database of all of these Palauan cultural 14C assays. This database will be suitable for developing and evaluating chronological models, an effort being undertaken as a separate paper. Prior to constructing prehistoric colonization and cultural chronologies for Palau, the validity of each assay and the relative adequacy in sample size per cultural and environmental zones must be examined. After systematic recalibration, the reliability of the dates is evaluated in light of sample material, cultural context, and site formation processes. A method for dating monumental earthwork complexes through site formation analysis is presented. Sets of 237 valid and 58 potentially valid 14C dates remain to develop chronological models. The representation of Palau's environmental zones, site types, and regions within the dating pool is examined and compared to ensure meaningfulness in these chronological models. Newly obtained 14C age determinations are also provided.