• 14C Dating of the Early Natufian at el-Wad Terrace, Mount Carmel, Israel: Methodology and Materials Characterization

      Eckmeier, Eileen; Yeshurun, Reuven; Weinstein-Evron, Mina; Mintz, Eugenia; Boaretto, Elisabetta (Department of Geosciences, The University of Arizona, 2012-10-15)
      The Natufian (15–11.5 kyr BP) sites in the southern Levant are characterized by a lack of macrobotanical remains, including charcoal, and poor preservation of bone collagen. As a result, only about 30 reliable radiocarbon dates are available for building a chronology of the Natufian period. Here, we present new 14C data from the Natufian site of el-Wad terrace that fall in the range of the Early Natufian period. Using Fourier transform infrared (FTIR) analysis, we investigated the environmental factors that influenced the preservation of material for 14C dating of the site, and we tested a modified pretreatment method for poorly preserved charcoal samples. The normal pretreatment protocol for 14C samples (W-ABA) removed more charcoal material than the modified method, which omits the first acid treatment (W-BA). This first acid step seems to enhance the extraction of humic substances during the subsequent base step. We found that the poor preservation of charcoal could be attributed to the presence of calcite, and therefore an alkaline pH of sediments. The most important factor determining bone collagen preservation may have been the hydrological setting, i.e. fluctuating water levels due to oversatu-ration of the dense sediments after rainfall.
    • Characterization of Contexts for Radiocarbon Dating: Results from the Early Iron Age at Tell es-Safi/Gath, Israel

      Toffolo, Michael; Maeir, Aren M.; Chadwick, Jeffrey R.; Boaretto, Elisabetta (Department of Geosciences, The University of Arizona, 2012-10-15)
      The reliability of a radiocarbon date depends in part on the degree of precision and accuracy of the measurement. While analytical precision and accuracy can be improved by careful sample cleaning procedures and high laboratory standards, accuracy also depends upon the certainty to which the sample can be attributed to a specific material culture or event in the past. This might be questionable when based only on partial archaeological information. As a consequence, it is very difficult to date clear-cut chronological transitions within specific periods. This issue is particularly apparent in the case of Mediterranean Iron Age chronology, where 2 somewhat different perspectives are proposed, the “High Chronology” and the “Low Chronology,” which differ by ~50 yr. Here, we present the preliminary results of an ongoing project that aims to characterize Iron Age archaeological contexts from the eastern Mediterranean, and to identify those contexts that are suitable for dating, in order to improve the accuracy of 14C dates. This study involves the analysis of sediments by means of FTIR spectrometry, soil micromorphology, phytolith and phosphate extraction, all of which provide insights into the site-formation and postdepositional processes at the different sites under investigation. These techniques, applied at Tell es-Safi/Gath (Israel), enabled us to better identify a secure context for dating.
    • Chronology of the Early Bronze Age in the Southern Levant: New Analysis for a High Chronology

      Regev, Johanna; de Miroschedji, Pierre; Greenberg, Raphael; Braun, Eliot; Greenhut, Zvi; Boaretto, Elisabetta (Department of Geosciences, The University of Arizona, 2012-10-15)
      The chronology of the Early Bronze Age (EBA) in the southern Levant and the synchronization between the sites, considering seriation and radiocarbon dates, have shown large inconsistencies and disagreement. We have assembled 420 14C dates, most of them previously published and a few provided directly by the excavators. The dates have been re-evaluated on the basis of their archaeological context and using analytical criteria. Bayesian modeling has been applied to the selected dates in relation to the given seriation of the EBA subperiods (EB I, II III, IV). Sites with 2 or more sequential subphases were individually modeled in order to define the transitions between the subperiods. The new chronology indicates that the EB I–II transition occurred site-dependently between 3200–2900 BC, with EB II–III around 2900 BC, and EB III–IV ~2500 BC.
    • Early Bronze Age Chronology: Radiocarbon Dates and Chronological Models from Tel Yarmuth (Israel)

      Regev, Johanna; de Miroschedji, Pierre; Boaretto, Elisabetta (Department of Geosciences, The University of Arizona, 2012-10-15)
      Over the years, 40 radiocarbon samples (charcoal and seeds) have been measured from the site of Tel Yarmuth. These samples originate from 3 major archaeological periods: Final Early Bronze Age (henceforth EB) I, EB II, and EB IIIB-C. The samples are further on divided into 8 separate archaeological phases. Bayesian modeling analyses were performed on the data. Separate models were run with seeds and charcoals to detect a possible old-wood effect. Outliers were detected, and finally models with gaps were run to account for the lack of samples from 2 archaeological layers. The results suggest that at Tel Yarmuth the end of the EB II occurred ~2950–2880 BC, and that the EB III ended at the latest ~2450 BC, perhaps before 2500 BC. Although these dates are somewhat earlier than traditionally assumed, they are in close accordance with the new analysis of other 14C dates for the Early Bronze Age in the southern Levant (Regev et al., these proceedings).
    • New 14C Dates for the Early Natufian of el-Wad Terrace, Mount Carmel, Israel

      Weinstein-Evron, Mina; Yeshurun, Reuven; Kaufman, Daniel; Eckmeier, Eileen; Boaretto, Elisabetta (Department of Geosciences, The University of Arizona, 2012-10-15)
      The Natufian culture of the southern Levant played an integral role in the transition from simple hunter-gatherers to food-producing societies of the Neolithic, but the major Natufian hamlets are currently poorly dated. Moreover, none of these complex, continuously occupied base camps have delivered an adequate number of dates to enable an in-depth delineation of intra-Natufian developments. This paper presents the first results of our dating program at el-Wad terrace, Mount Carmel (Israel), one of the major Natufian hamlets of the “core area” of this culture. Thirteen accelerator mass spectrometry (AMS) radiocarbon age determinations were obtained from 46 bone (both ungulate and human) and charcoal samples, originating in Early Natufian living surfaces, dwellings, and burials. The obtained dates are largely in agreement with the cultural affiliation of the samples (13–15 kyr cal BP). Two series of dates from different locations show good agreement with the stratigraphy. The ages of the burials clearly point to their being younger than the living surfaces seemingly associated with them. Presently, no burials may be linked with the major architectural phase of Early Natufian el-Wad. Our ongoing dating program and the processing of additional samples from refined contexts will help shed important light on the initial phases of the Natufian culture, habitation duration, intensity, and continuity, as well as the relationships between site features and stratigraphy.
    • Plaster Characterization at the PPNB Site of Yiftahel (Israel) Including the Use of 14C: Implications for Plaster Production, Preservation, and Dating

      Poduska, Kristin M.; Regev, Lior; Berna, Francesco; Mintz, Eugenia; Milevski, Ianir; Khalaily, Hamudi; Weiner, Steve; Boaretto, Elisabetta (Department of Geosciences, The University of Arizona, 2012-10-15)
      The Pre-Pottery Neolithic B (PPNB) site of Yiftahel, Israel, contains abundant plaster floors. We surveyed the states of preservation of the plasters using an infrared spectroscopic assay that characterizes the extent of disorder of the atoms in the calcite crystal lattice. We identified the 3 best-preserved plaster samples that had disorder signatures most similar to modern plaster. We then studied the surface layers, fine-grained matrices, and large aggregates of these samples using micromorphology, Fourier transform infrared (FTIR) microscopy, stable carbon and radiocarbon concentrations. Even though some of the plaster components have a geogenic appearance in micromorphology slides and in FTIR spectra, the 14C analyses show that all components were exposed to high temperatures and as a result were equilibrated with the 14C content of the atmosphere ~10,000 yr ago. This implies that the plasters at Yiftahel were produced entirely from heat-altered calcite. We also show that these plasters have undergone significant diagenesis. The plaster component with the most disordered atomic signature, and hence the most similar in this respect to modern plaster, did indeed produce a 14C date close to the expected age.
    • Preface from the Guest Editors

      Boaretto, Elisabetta; Rebollo Franco, Noemi (Department of Geosciences, The University of Arizona, 2012-10-15)