1,1,1,1,1,3,1- 1Silesian University of Technology, Institute of Physics - CSE, Division of Geochronology and Environmental Isotopes, Gliwice, Poland (danuta.michczynska@polsl.pl)
- 2University of Szczecin, Institute of Marine and Environmental Sciences
- 3Silesian University of Technology, Faculty of Biomedical Engineering
Marine shells are commonly used for determination and correction of marine reservoir effect (MRE); however, their susceptibility to surface contamination makes sample treatment a critical step in obtaining reliable ¹⁴C results.
In this study, marine shells collected from living specimens of common cockle (Cerastoderma glaucum) from the Baltic Sea, were investigated as modern reference material for a ¹⁴C-based assessment of the marine reservoir effect. A series of preparation protocols was applied to evaluate the influence of different cleaning and CO2 extraction methods on radiocarbon measurements.
In the first stage, shell cleaning involved mechanical surface cleaning, ultrasonic bath treatment, and rinsing in hydrochloric acid (HCl). The aim of these procedures was to remove potential contaminants and algal material from the shell surface.
In the subsequent stage, carbon dioxide (CO2) was extracted from shell carbonate using different analytical approaches. These methods included dissolution of whole shells in orthophosphoric acid (H3PO4) under vacuum conditions, with sequential collection of CO2 fractions after 15 and 30 minutes of dissolution, as well as a final fraction obtained after complete dissolution of the material. In addition, CO2 was extracted from crushed shell material, by dissolution in orthophosphoric acid carried out in the presence of helium (He) atmosphere. Alongside the shell carbonate samples, algal material collected from the shell surfaces was also measured for radiocarbon content, to assess potential differences between coexisting carbon reservoirs.
The comparison of preparation and extraction methods provides insight into methodological factors affecting radiocarbon measurements of modern marine shells and contributes to improving the reliability of MRE determination in the Baltic Sea.
The participation of DJM, AM and NP in the EGU 2026 General Assembly was funded by the project EU funds FSD - 10.25 Development of higher education focused on the needs of the green economy European Funds for Silesia 2021-2027: The modern methods of the monitoring of the level and isotopic composition of atmospheric CO2 (project no. FESL.10.25-IZ.01-06C9/23-00).
How to cite: Michczynska, D. J., Michczyński, A., Piotrowska, N., Bolik-Głuszek, A., Kamińska, A., Borówka, R. K., Mainka, M., Wojcik, M., and Zakrzewska, Z.: ¹⁴C-based investigation of the marine reservoir effect using shells collected from living specimens of common cockle (Cerastoderma glaucum) from the Baltic Sea, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11851, https://doi.org/10.5194/egusphere-egu26-11851, 2026.
