Radiocarbon Dating of Marine Samples: Methodological Aspects, Applications and Case Studies

Radiocarbon dating by AMS (Accelerator Mass Spectrometry) is a well-established absolute dating technique widely used in different areas of research for the analysis of a wide range of organic materials. Precision levels of the order of 0.2–0.3% in the measured age are nowadays achieved while several international intercomparison exercises have shown the high degree of reproducibility of the results. This paper discusses the applications of 14C dating related to the analysis of samples up-taking carbon from marine carbon pools such as the sea and the oceans. For this kind of samples relevant methodological issues have to be properly addressed in order to correctly interpret 14C data and then obtain reliable chronological frameworks. These issues are mainly related to the so-called “marine reservoirs effects” which make radiocarbon ages obtained on marine organisms apparently older than coeval organisms fixing carbon directly from the atmosphere. We present the strategies used to correct for these effects also referring to the last internationally accepted and recently released calibration curve. Applications will be also reviewed discussing case studies such as the analysis of marine biogenic speleothems and for applications in sea level studies.