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Cova Bonica has yielded one of the few assemblages of Cardial Neolithic records of directly dated human remains (c. 5470 and 5220 years cal. BC – unmodelled) in the Iberian Peninsula and has provided the first complete genome of an Iberian farmer. A minimum of seven individuals and six age clusters have been ascribed on the basis of the disarticulated human bones. A large number of archaeological artifacts have likewise been identified in the same layer, preserved in a small number of remnants in different areas of the cave. This study presents the results of a multi-proxy archaeological analysis of the spatial distribution, human remains, small and large mammals, palaeobotanical remains, lithics, ceramics and radiocarbon dating, with the aim of reconstructing the cave's history and the context of the layer containing the human remains. The results suggest the cave was used for at least two distinct purposes: one related to its use for funerary practices, as documented by a small group of artifacts (ornamental objects, ceramics, tools), charcoal and small mammals; the other related to its use as a sheep pen as indicated by reworked fumier, the results of a zooarchaeological study and an ovicaprine palaeodemographic profile. The paper concludes that the funerary and ritualistic practices of the Cardial Neolithic in SW Europe are difficult to reconstruct because human remains are often scattered in archaeological layers where other human activities may also have been conducted. For this reason, artifacts associated with human remains do not constitute a solid foundation on which to reconstruct funerary practices. Indeed, only a multi-proxy analysis of the archaeological material is capable of evaluating different geological and/or archaeological processes and their associated activities., The results presented here represent the research outcomes of the following projects: El Plistocè superior a la costa central catalana: paleoambients i ocupacions neandertals (2014/100639- Servei d'Arqueologia i Paleontologia) and Els canvis climàtics durant el plistocè superior a la costa central catalana i l'impacte en les poblacions neandertals i humans anatòmicament moderns, supported by projects 2017SGR-00011, HAR2017-86509, HAR2016-75201-P and CGL2015-65387-C3-2-P (MINECO/FEDER). J. Daura was supported by a Ramon y Cajal contract (RYC-2015-17667) and M. Sanz by a Juan de la Cierva contract (IJCI-2017-33908). Fieldwork was also sponsored by the Ajuntament de Vallirana. We thank the Museu de Gavà (Spain) for permission to date the human remains number 19a/b (Gavà-1 Mandible 1982) and 20a/b (Gavà-2 Mandible 1978).

Radiocarbon (14C) measurements of foraminifera are often challenging as their reliability and accuracy can be biased by several complicating factors. In this work, at the Centro Nacional de Aceleradores (CNA) in Seville, an automated setup with a Carbonate Handling System coupled with an automated graphitization system has been tested to investigate the potential for running samples of foraminiferal carbonate for AMS 14C dating of marine archives. The reproducibility of 14C ages for blanks and standard materials indicates that reliable 14C analyses are possible for carbonate samples with a 14C age up to 50,000 yr BP. With this automated procedure we were able to date monospecific planktonic foraminifera younger than 1000 yr BP. Biological mixing and high sedimentation are potentially complicating mechanisms resulting in anomalous young 14C ages in planktonic foraminifera from the deep Mediterranean Sea., The research leading to these results was supported by the European Science Foundation (ESF) Exchange Visit Grant 5103 ‘Dating and TIming of fluxes into and out of the MarinE CArbon Reservoir of the MeDiterranean Sea (TIMECARD)’ under the Research Networking Programme Earthtime – The European Contribution (EARTHTIME-EU). We are deeply indebted to Leonardo Langone from the CNR-ISMAR for providing the planktonic foraminifera samples along with numerous geochemical proxies used to interpret data from this study.

This paper evaluates the complexities of radiocarbon (14C) dates from soil organic matter (SOM) in archaeological scenarios. The aqueous NaOH-insoluble residual SOM from Neolithic to medieval sites in NW Spain produced consistently older calibrated 14C ages than NaOH-extractable SOM. Using pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) and thermally assisted hydrolysis and methylation (THM-GC-MS), we analyzed the molecular composition of these SOM fractions, aiming to understand the differences in 14C ages and to gain insight on SOM dynamics in relation to age fractionation. The molecular composition of the NaOH-extractable SOM, which accounts for roughly two-thirds of total SOM, has a larger proportion of microbial detritus than the NaOH-insoluble SOM. This might suggest that the discrepancies between the two fractions is due to microbial rejuvenation in the extractable fraction, leading to 14C results that are younger than the activity that is to be dated. However, archaeological evidence presented here unambiguously shows that the 14C age of the extractable SOM provides the more accurate age for the targeted activity, and that the insoluble fraction contains inherited old carbon. After statistical data evaluation using Partial Least Squares-Regression (PLS-R), it is concluded that this inherited SOM is a mixture of Black Carbon from wild and/or domestic fires and recalcitrant aliphatic SOM., Cruz Ferro-Vázquez has been funded by the People Programme (Marie Curie Actions) of the European Union’s Horizon 2020 Programme (tRRACES-H2020-MSCA-IF-2014-657355). Radiocarbon analyses have been funded by the Institute of Heritage Sciences from the Spanish National Research Council (Incipit-CSIC) and the Consolider Programme CSD2007-0058 (MINECO, Spain).

The Sixth International Radiocarbon Intercomparison (SIRI) exercise has taken place during late 2013 and 2014. 13 samples were distributed for AMS (Accelerator Mass Spectrometry) and 5 for radiometric laboratories, including one sample exclusively for radiometric laboratories. Being the first opportunity for our laboratory to participate actively in an intercomparison exercise, we have prepared and measured the samples in the two existing AMS dedicated facilities at the Centro Nacional de Aceleradores (CNA): SARA (Spanish Accelerator for Radionuclide Analysis), a 1 MV multielemental AMS system from HVEE, and Micadas, a 200 kV radiocarbon dating system designed by ETH. Results are presented for the two systems, together with a description of both the sample preparation and measurement procedures., This work has been partially financed by the project FIS2012-31853 of the Spanish Ministerio de Economía y Competitividad.

Radiocarbon determination can be used as a tool to investigate the presence of biological elements in different bio-based products, such as biodiesel blends. These products may also be produced from fossil materials obtaining the same final molecules, so that composition is chemically indistinguishable. The amount of radiocarbon in these products can reveal how much of these biological elements have been used, usually mixed with petrol derived components, free of 14C. Some of these products are liquid and thus the handling at the laboratory is not as straightforward as with solid samples. At Centro Nacional de Aceleradores (CNA) we have tested the viability of these samples using a graphitization system coupled to an elemental analyzer used for combustion of the samples, thus avoiding any vacuum process. Samples do not follow any chemical pre-treatment procedure and are directly graphitized. Specific equipment for liquid samples related to the elemental analyzer was tested. Measurement of samples was performed by low-energy AMS at the 1 MV HVEE facility at CNA, paying special attention to background limits and reproducibility during sample preparation., This work has been partially financed by the Project FIS2012-31853 of the Spanish Ministerio de Economía y Competitividad.

Artículo presentado al "Eleventh International Conference on Accelerator Mass Spectrometry" celebrado en Roma del 14 al 19 de Septiembre del 2008.-- El pdf del artículo es la versión de autor., Eleven samples (parchment and paper) from different medieval manuscripts belonging to the cultural heritage of the University of Seville have been radiocarbon dated on the 1 MV AMS facility at the CNA in Seville (Spain). The objective of this study is double. First of all, these are the first real >unknown> samples treated in the radiocarbon laboratory and dated on our AMS facility, SARA (Spanish Accelerator for Radionuclide Analysis). Besides, some useful information about the manuscripts can be obtained, either to corroborate the dates, or in some cases, to decide between possible dates. As expected, a general agreement is found between radiocarbon results and palaeographical data. Nevertheless, some interesting facts have been learned through this study. We present in this paper the procedure to prepare the samples and the ages obtained with a brief discussion of the results. © 2009 Elsevier B.V. All rights reserved., This work has been partially financed by the project EXC/2005/RNM-419 of the Junta de Andalucía.

Trabajo presentado a la II International Conference on Radioecological Concentration Processes (50 years later), celebrada en Sevilla (España) del 6 al 9 de noviembre de 2016., Carbonate shells from foraminifera are often analyzed for radiocarbon to determine the age of deep-sea sediments or to assess radiocarbon reservoir ages. The Centro Nacional de Aceleradores (CNA) is equipped for the AMS radiocarbon analysis with a MICADAS (MIni CArbon DAting System), and a sample processing line including vial flushing, carbonate dissolution and transfer of the evolved CO2 from the septum sealed tubes to the automated graphitization equipment (AGE). In this work, we have tested a fullyautomated setup from sampling the released CO2 from small carbonate samples (i.e. foraminifera shells) for radiocarbon analysis, where the formed CO2 is later flushed by helium flow by means of a double-wall needle mounted from the tubes to the zeolite trap of the existing AGE-2. This carbonate dissociation line essentially replaces the elemental analyser normally used for the combustion of organic samples to further reduce the effort involved for sample preparation. The automated method yields in low sample blanks of about 50,000 years. Results of the processed reference materials (IAEA-C1 and IAEA-C2) are in agreement with their consensus values. Using this automated dissociation line we were able to date samples of monospecific foraminifera shells (~10 mg) of ~ 1000 radiocarbon years., This project was supported by the European Science Foundation (ESF) Exchange Visit Grant 5103 ‘Dating and TIming of fluxes into and out of the MarinE CArbon Reservoir of the MeDiterranean Sea (TIMECARD)’ awarded within the Research Networking Programme Earthtime – The European Contribution (EARTHTIME-EU).