Because hard tissues can be radiocarbon dated, they are key to establishing the archaeological chronologies, palaeoenvironmental reconstructions and historical-biogeographical processes of the last ...50,000 years. The advent of accelerator mass spectrometers (AMS) has revolutionized the field of archaeology but routine AMS dating still requires 60-200 mg of bone, which far exceeds that of small vertebrates or remains which hold a patrimonial value (e.g. hominid remains or worked bone artefacts). Here, we present the first radiocarbon dates obtained from minute amounts of bone (3-60 mg) using a MIni CArbon DAting System (MICADAS). An optimized protocol allowed us to extract enough material to produce between 0.2 and 1.0 mg of carbon for graphite targets. Our approach was tested on known-age samples dating back to 40,000 BP, and served as proof of concept. The method was then applied to two archaeological sites where reliable dates were obtained from the single bones of small mammals. These results open the way for the routine dating of small or key bone samples.
The Grotte Cosquer (southeastern France) is a Paleolithic painted cave only accessible by a deep-water dive. The cave has yielded numerous Paleolithic engravings and drawings, which were produced ...from wood charcoal. This article presents new radiocarbon dates obtained on samples collected in 2012 directly on 17 parietal representations and at the soil surface, and discusses the 14C results obtained since the discovery of the cave in 1992. A total of 41 samples were dated with ages ranging from 33,000 to 20,000 cal BP. They show that the cave was intermittently decorated over about 10,000 yr.
In this paper, we explain our routine pretreatment of bone for radiocarbon dating by accelerator mass spectrometry (AMS), based on the specific reaction between amino acids and ninhydrin described by ...Nelson (1991). The values and uncertainties of the total system background are presented as a function of the carbon sample mass and the reliability of this method is discussed.
Abstract
Secondary carbonate deposits (similar to speleothems) in urban undergrounds, have been recently highlighted as powerful archives for reconstruction of the historical anthropogenic imprint on ...the environment. The precise chronology of these secondary carbonate deposits is a key issue for the accurate time reconstruction of environmental conditions. We present three
14
C data sets for urban speleothem-like deposits that developed in contrasted man made environments. The first one was sampled in an underground technical gallery of the Palace of Versailles (France), and the other two in a manhole (Saint-Martin spring) of a historical underground aqueduct in Paris (France). The comparison of these records with the bomb peak and relative chronology (laminae counting) allowed us to identify: i) fast carbon transfer from the atmosphere to the urban underground; ii) a high proportion of dead carbon and a high damping effect in relation to possible old carbon stored within urban soils and/or the influence of local fossil carbon burning. This study also shows that the lamination of these deposits is bi-annual in these highly urbanized sites.
Secondary carbonate deposits (similar to speleothems) in urban undergrounds, have been recently highlighted as powerful archives for reconstruction of the historical anthropogenic imprint on the ...environment. The precise chronology of these secondary carbonate deposits is a key issue for the accurate time reconstruction of environmental conditions. We present three 14C data sets for urban speleothem-like deposits that developed in contrasted man made environments. The first one was sampled in an underground technical gallery of the Palace of Versailles (France), and the other two in a manhole (Saint-Martin spring) of a historical underground aqueduct in Paris (France). The comparison of these records with the bomb peak and relative chronology (laminae counting) allowed us to identify: i) fast carbon transfer from the atmosphere to the urban underground; ii) a high proportion of dead carbon and a high damping effect in relation to possible old carbon stored within urban soils and/or the influence of local fossil carbon burning. This study also shows that the lamination of these deposits is bi-annual in these highly urbanized sites.
This paper reports on the three seasons of excavations conducted at Eynan (Ain Mallaha) from 2003 to 2005. It is also aimed at recording the laboratory work that took place since the last report ...published (Valla et al. 2004). Following the presentation of new 14C dates, the paper describes Early Natufian burials (Locus 239), one of which includes two decorated skeletons in a plastered grave. The next sections are devoted to analyses of Final Natufian findings. Because most of the sequence inside each excavated structure is now known, special interest is devoted to the succession of the phases in their occupation. This results in a dynamic vision, which suggests that some buildings (possibly houses) were used intermittently, whereas others may have been occupied on a more continuous basis. Among new features uncovered during those last seasons, a fire pit in structure 228 and a structure that includes a deep mortar in working position are worth mentioning. New graves are described as well. The most unexpected among them is a pit where at least seven individuals from newborn to adult were successively buried. Lithic analyses include an attempt at reconstructing the way both Helwan and regular Final Natufian lunates were shaped. This demonstrates that the changes in retouch techniques are probably linked to the diminished size of the desired end product. Following a more traditional approach we examine then a sample of tools from the lower part of the Final Natufian layer. The results suggest that there is no major change in the flint assemblages during the time span represented by the layer. Obsidian study confirms that this material is coming from Cappadocia, as will be the case in the Southern Levant for most of the PPN. Faunal analyses include a note on mammal carcass treatment. New research on birds confirms that Final Natufian people mainly targeted waterfowls for food but new species of raptors are identified. A preliminary analysis of fish emphasizes the diversity in species. Two studies are devoted to crabs and land and freshwater mollusks respectively. They suggest that both crabs and terrestrial mollusks were probably used as food by the inhabitants of the site. Also of importance is the presence of Palearctic mollusks, which confirm that average temperatures were probably somewhat lower by the end of the Pleistocene than to day, as already suggested by Pichon. More bone tools confirm the trends already observed previously: this workmanship is deeply rooted in the tradition initiated during the Early Natufian phase. Hooks are relatively frequent. Of interest is the finding of a new "spoon", a tool that seems to be a Natufian invention. Due to poor preservation of vegetal remains, phytoliths are the main testimony of the use Natufian people made of flora. New samples confirm that reeds and sedges may have been used for building and matting, whereas a variety of grasses, among them small quantities of barley and wheat, were probably brought to the site for consumption. Finally, preliminary presentations of shell and stone beads are offered, followed by a description of the few incised stone items recovered lately. A discussion emphasizes the many time scales involved in the findings and the possible different readings allowed thereby.
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