TUNGUSKA99 Expedition

Radiometric analysis of the 1999 peat sample allowed to determine the levels of natural and fallout radionuclides: a Cs-137 inventory of 4.6 kBq m-2 has been found and a mean annual flux of 200 Bq m-2 of Pb-210 has been estimated at this site. The Pb-210 geochronology of this core placed the 1908 horizon at - 42 cm. At this level an intense peak of tree total pollens and Sphagnum spores was found. Elemental analysis by PIXE of the 2002 peat sample did not reveal so far TCB microtraces thus suggesting further analytical efforts (see figure, article, 1.15 Mb and abstract, 6 kb).

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