Sedimentation Rate in Cheko Lake (Evenkia, Siberia): New Evidence on the Problem of the 1908 Tunguska Event

摘要

We estimated the age and sedimentation rate of bottom sediments in Cheko Lake located in southern Evenkia, in the territory of Tunguska Nature Reserve, near the supposed epicenter of the so-called 1908 Tunguska Event. The vertical distributions of Cs-137 and Pb-210 activity and visually counted varves in the core of lake bottom sediments indicate that Cheko Lake is significantly older than the 1908 Tunguska Event; therefore, the lake basin cannot be a crater or a trace of the explosion as was supposed earlier by some researchers.