Using fallout radionuclides to investigate recent overbank sedimentation rates on river floodplains: an overview

Abstract. Information on rates of overbank sedimentation on river floodplains is needed for a variety of purposes. Use of ¹³⁷Cs and ²¹⁰Pbex measurements provides an effective means of estimating medium-term floodplain sedimentation rates and that approach has now been successfully used in many areas of the world. This contribution reviews the use of ¹³⁷Cs and ²¹⁰Pbex measurements in floodplain sedimentation investigations and discusses some of the important sampling requirements and key issues associated with interpreting the measurements, and subsequently deriving reliable estimates of sedimentation rates. The potential use of other radionuclides, including ²⁴¹Am, ^238,239+240Pu, and ⁷Be is considered, and the advantages of using two or more radionuclides, in combination, is highlighted.