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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.

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.