Global 137Cs as a sediment marker in deep lakes

Global 137Cs is used as a marker for identification of a bottom sediment layer whose age corresponds to the maximal contamination of the hydrosphere with radiocesium in 1964. This method allowed determination of the current sediment accumulation rate in deep lakes. For an Arctic lake with the maximal depth of 110 m (Central Taimyr), the sediment accumulation rate is estimated to be 0.8-3.0 mm/year. The relatively long lifetime of 137Cs (30 years) is sufficient to provide long-time monitoring of the sedimentation of nonradioactive materials in deep lakes. © 2007 Pleiades Publishing, Inc.