Mazar and Bronk Ramsey (2008) recently proposed that the Iron I/IIA transition in the Levant took place during the first half of the 10th century. In the first part of this article, we challenge their method and conclusions. We argue against the inclusion of charcoal in their model, which could lead to an 'old wood effect.' We also argue that in dealing with a transition date, all available data must be taken into consideration. In the second part of the article, we propose Bayesian Model I for the Iron I/IIA transition, which is based on 2 sets of data--for the periods immediately before and after this transition. Our model, along with the other 11 published Bayesian models for this transition that used only short-lived samples, agrees with the Low Chronology system for the Iron Age strata in the Levant and negates all other proposals, including Mazar's Modified Conventional Chronology. The Iron I/IIA transition occurred during the second half of the 10th century. In the third part of the article, we present a new insight on the Iron I/IIA transition. We propose that the late Iron I cities came to an end in a gradual process and interpret this proposal with Bayesian Model II. Mazar and Bronk Ramsey (2008) recently challenged Sharon et al. (2007; also Boaretto et al. 2005) and us (e.g. Finkelstein and Piasetzky 2003, 2007a,b) regarding the date of transition from the Iron I to the Iron IIA in the Levant. While we and Sharon et al. placed this transition in the second half of the 10th century BCE, Mazar and Bronk Ramsey positioned it 'during the first half of the 10th century BCE' and argued that 'the second half of the 10th century BCE should be included in the Iron IIA' (Mazar and Bronk Ramsey 2008:178). We discuss some problems in the methodology of Mazar and Bronk Ramsey that may have influenced their results. In particular, we discuss 1) the exclusion of data; 2) the inclusion of data (charcoal samples); and 3) show that even according to Mazar and Bronk Ramsey, excluding these samples position the late Iron I/IIA transition in the late 10th century. Finally, we present our own 2 Bayesian models for the Iron I/IIA transition.

14C and 13C values of C-containing species in cave drip waters are mainly controlled by the C isotope composition of karst rock and soil air, as well as by soil carbon dynamics, in particular the amount of soil CO2 in the unsaturated soil zone and the process of calcite dissolution. Here, we investigate soil carbon dynamics by analyzing the 14C activity and 13C values of C dissolved in cave drip water. Monthly over a 2-yr period, we collected drip water from 2 drip sites, one fast and one relatively slow, within the shallow Grotta di Ernesto Cave (NE Italy). The 14C data reveal a pronounced annual cycle. In contrast, the 13C values do not show an annual pattern and only small interannual variability compared to the 13C values of soil waters. The annual 14C drip-water cycle is a function of drip-rate variability, soil moisture, and ultimately hydrology.

Construction of a new science complex in Osong, Cheongwon-gun, Korea, has allowed the investigation of 14 different Paleolithic localities, excavated during 2005-2007. Here, we investigated localities 1 and 12 of the Mansuri Paleolithic site to obtain chronological information using radiocarbon dating. The soil deposition rates varied from 0.09 to 0.15 mm/yr over the period ranging from 33 to 31 kyr BP for locality 1. Locality 12 samples were more recent, 10 ka, and have similar accumulation rates, averaging 0.11 mm/yr. The soil ages of locality 12 were found to be younger than 10 kyr BP. Results for both soil and organic materials at this locality gave much younger ages at shallower depths than the ages expected by the Korean Paleolithic cultural history for this region. Therefore, these more recent deposits may not be associated with the cultural layers and are interpreted to have been hydrologically modified following emplacement. 14C dates of the soil and organic materials at locality 12 confirm that there is evidence for multiple human occupations throughout the last 9 kyr BP.

We measured the radiocarbon ages of 165 single-year tree rings from a Japanese Choukai Jindai cedar using accelerator mass spectrometry (AMS). By wiggle-matching the Choukai_AMS data set to the IntCal04 calibration data using OxCal v 3.10 and using the variation of the correlation coefficients between the Choukai_AMS and IntCal04 data sets, we precisely re-estimated that the 321 Choukai Jindai cedar tree rings range from 780 to 460 cal BC with an accuracy of 8 yr. The Choukai_AMS data set is older than the 3 raw data sets of European tree rings that comprise IntCal04. The Belfast and Seattle data sets are younger by -21.3 +/- 5.5 and -22.7 +/- 5.6 14C yr, respectively. The Choukai Jindai cedar is ~22 14C yr older than the European tree rings, which is equivalent to an offset of -2.8‰ in 14C. In addition, the Choukai_AMS data set correlates well with the Belfast and Seattle data sets, with correlation coefficients of 0.89 and 0.68, respectively, between the temporal profiles. Hence, the temporal profile of the Choukai 14C ages shows a global variation.

We describe a new compilation of radiocarbon age measurements performed by the NERC Radiocarbon Laboratory that is freely available to access over the World Wide Web. The database contains 1000 14C measurements performed using the liquid scintillation counting method between 1996 and 2005, and further results will be added as the information is compiled. Contextual information including sampling location and the nature of sample material is provided, alongside 14C age results and publications codes. Hypertext links provide access to the original 14C age report associated with the samples, providing additional details. The 14C measurements were originally performed for earth and environmental science NERC projects and are therefore likely to be most relevant to the Quaternary research community.

The relationship between temperature and time required for collagenization using modern bone samples was investigated. Gelatinized samples of bone collagen were filtered to selectively collect different molecular weight fractions. The results of this study suggest that heating to 70 degrees C for a duration of 12 hr provides the optimal conditions for gelatinization.

The national project for the measurement of radiocarbon includes different scientific partners for the accelerator named ARTEMIS (French acronym for Accélérateur pour la Recherche en sciences de la Terre, Environnement, Musologie Install Saclay), available to the scientific community since 2004 (Cottereau et al. 2007). The French Ministry of Culture uses this accelerator mass spectrometry (AMS) facility at the request of archaeologists or curators of museums or of historical monuments. For the preparation of some samples, a laboratory has been installed at the Centre of Research and Restoration of the Museums of France, located in the Louvre Palace. In this report, the first data carried out on vegetal samples from museum objects or archaeological remains, dates are presented in terms of yr BP (before AD 1950).

Determining the appropriate approach to calibrating radiocarbon dates is challenging when unknown and variable fractions of the carbon sample are derived from terrestrial and marine systems. Uncalibrated dates from a large number of human skeletons from Western Cape and Southern Cape locales, South Africa (n = 187), can be used to explore alternate approaches to the marine carbon correction. The approach that estimates theoretically expected minimum and maximum values for marine carbon ("expected") is compared to the approach that estimates observed minimum and maximum values ("observed"). Two case studies are explored, wherein skeletons interred together have non-overlapping conventional 14C ages. The case from the Western Cape is explored through carbon isotope values; the case from the Southern Cape uses nitrogen isotope values. In both cases, the approach using observed endpoints yields better date calibration results. Analysis of the large sample shows that mean values for estimated dietary % Marine, as calculated using expected and observed protocols, are significantly different. We conclude that the observed protocol is preferred, and that improved measures of the local marine reservoir (∆R) are needed for this region.

The East Mediterranean Radiocarbon (inter-)Comparison Project (EMRCP) has measured the 14C ages of a number of sets of tree rings from the Gordion Area dendrochronology from central Anatolia at the Heidelberg Radiocarbon Laboratory. In several cases, multiple measurements were made over a period from the 1980s to 2009. This paper presents the final data set from this work (128 high-precision measurements), and considers (i) the relationship of these data against the standard Northern Hemisphere 14C calibration data set (IntCal09), and (ii) the optimum calendar dating of this floating tree-ring record on the basis of the final set of high-precision 14C data. It finds good agreement between the Anatolian data and IntCal09 in some important intervals (e.g. ~1729 to 1350 cal BC) and observes one period (9th-8th centuries BC) where there appears to be some indication of a regional/growing season signal, and another period (later 14th-13th centuries BC) where IntCal09 may not best reflect the real 14C record. The scale of the typical growing-season-related regional 14C offset (Delta-R) between the Aegean/Anatolian region and IntCal09 is also assessed (for the mid-2nd millennium BC and mid-2nd millennium AD), and found to be usually minor (at times where there are no major additional forcing factors and/or issues with the IntCal09 data set): of the order of 2-4 +/- 2-4 yr.