DOI: 10.1594/pangaea.925059
title: Radiocarbon data determined on sediments from loess paleosol sequence BAK

description: This dataset contains radiocarbon (14C) ages analysed on the loess-paleosol sequences (LPS) Balta Albă Kurgan (Romania). The data was obtained to test the robustness of different dating methods (14C analysis, luminescence dating, magnetic stratigraphy, tephrochronology) on this type of sediment archive. The data set includes 14C ages obtained on bulk organic carbon (OC) and on specific n-alkanes and n-alkanoic acids (Compound-specific 14C analysis).Sample preparation for bulk OC 14C analysis included removal of root remains and a standard acid-alkali-acid (AAA) protocol chemical treatment. Bulk OC was converted to graphite and analysed for 14C at the CologneAMS facility at the University of Cologne (Rethemeyer et al., 2019). The background of this specific suite of samples was determined to 42,700±590 14C years (F14C=0.0049±0.0004, fraction modern, Reimer et al., 2004) with size matched standards.For compound-specific 14C analysis n-alkanes and n-alkanoic acids were purified from sediment samples by using standard wet-chemical methods (see Scheidt et al. in press). Isolation of individual compounds was achieved by using a gas chromatograph coupled to a preparative fraction collector (PCGC). 14C analysis was done with an elemental analyser coupled to a gas injection system (EA-GIS) periphery at CologneAMS (Stolz et al., 2019). F14C values of lipid biomarker compounds were corrected for a constant contamination of 1.0±0.1 µg C with an F14C value of 0.44±0.05 introduced during EA-GIS sample preparation and analysis, and for the PCGC processing blank (F14C=0.25±0.017 and 0.6±0.3 µg C). n-Alkanoic acids were corrected for the addition of one methyl group added during transesterification using mass balance.Calibration of 14C ages was done using the IntCal20 dataset (Reimer et al., 2020) and are given as 95% (2σ) confidence intervals.A detailed description of the analyses and discussion of the 14C ages can be found in the publication “Chronological assessment of the Balta Alba Kurgan loess-paleosol section (Romania) – a comparative study on different dating methods for a robust and precise age model” by Scheidt et al. in press.Reimer, P.J., Austin, W.E.N., Bard, E., Bayliss, A., Blackwell, P.G., Bronk Ramsey, C., et al. (2020). The INTCAL20 Northern Hemisphere Radiocarbon Age Calibration Curve (0–55 CAL kBP). Radiocarbon, 1-33. doi: 10.1017/RDC.2020.41.Reimer, P.J., Brown, T.A., and Reimer, R.W. (2004). Discussion: reporting and calibration of post-bomb 14C data. Radiocarbon 46(3), 1299-1304.Rethemeyer, J., Gierga, M., Heinze, S., Stolz, A., Wotte, A., Wischhöfer, P., et al. (2019). Current Sample Preparation and Analytical Capabilities of the Radiocarbon Laboratory at CologneAMS. Radiocarbon 61(5), 1449-1460. doi: 10.1017/RDC.2019.16.Scheidt, S., Berg, S., Hambach, U., Klasen, N., Pötter, S., Stolz, A., Veres, D., Zeeden, C., Brill, D., Brückner, H., Kusch, S., Laag, C., Lehmkuhl, F., Melles, M., Monnens, F., Oppermann, L., Rethemeyer, J., Nett, J. (in press) Chronological assessment of the Balta Alba Kurgan loess-paleosol section (Romania) – a comparative study on different dating methods for a robust and precise age model. Frontiers in Earth Science, section Sedimentology, Stratigraphy and DiagenesisStolz, A., Dewald, A., Heinze, S., Altenkirch, R., Hackenberg, G., Herb, S., et al. (2019). Improvements in the measurement of small 14CO2 samples at CologneAMS. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 439, 70-75. doi: https://doi.org/10.1016/j.nimb.2018.12.008.