A worldwide meta-analysis (1977–2020) of sediment core dating using fallout radionuclides including 137 Cs and 210 Pb xs

Abstract. Dating recent sediment archives ( https://doi.pangaea.de/10.1594/PANGAEA.931493 ). This review was conducted in order to map the locations where 137Cs fallout events were detected. These included the thermonuclear bomb testing peak in 1963, the Chernobyl accident in 1986, the Fukushima accident in 2011, and 24 additional events identified in 112 sites that led to local radioactive releases (e.g. Sellafield accidents, Chinese nuclear tests). When 210Pbxs records were used along with 137Cs data, detailed information on the 210Pbxs age depth models were also synthesized. Multiple information including the core collection method, sediment properties, radionuclide analysis techniques and catchment characteristics were also compiled. With the current growing number of studies analyzing sediment cores and the increasing interest in the deployment of sediment fingerprinting techniques including radionuclides as potential discriminant properties, this spatialized synthesis provides a unique worldwide compilation for characterizing fallout radionuclide sources and levels at the global scale. This synthesis provides in particular a referential of 137Cs peak attribution for improving the sediment core dating and it outlines the main questions that deserve attention in future research as well as the regions where additional 137Cs fallout investigations should be conducted in priority.