Geochemical and Isotope Anomalies in Sioma River Gorge, Western Tajikistan

For a better understanding of the previously observed increased natural radioactivity at confluence Varzob and Sioma rivers, Central Tajikistan, activity concentration radioactive 40K, Th U daughters as well anthropogenic 137Cs were determined in nine locations covering entire River. The radiometric determinations evidenced, addition to concentrations daughter radionuclides, an anomalous accumulation anthropic 210Pb middle gorge. Complementarily, mass fractions by instrumental neutron activation analysis evidenced presence U, which, some places, overpasses six-times average fraction found upper continental crust. possible influence active air transport from southern Tadjik plane during Afghani storms, actinide-rich minerals, analyzed discussed.