SINGLE-PARTICLE CHARACTERIZATION OF INORGANIC SUSPENSION IN LAKE BAIKAL, SIBERIA

Automated and manual electron probe X-ray microanalyses were used to c haracterize the chemical composition and morphology of individual susp ended particles, collected at different tributaries of Lake Baikal and in the central part of southern Lake Baikal. The data sets were reduc ed using hierarchical clustering, and the results were compared by mea ns of selection rules. All the samples are dominated by natural alumin osilicates and Si-rich particles. But small amounts of anthropogenic a luminosilicates (i.e., fly ash); Fe-rich, Al-rich, Cr-rich, and Zn-ric h particles; and Cl-coated fibers were also detected. The contaminatio n is especially severe in the southern basin, which can easily be reac hed by atmospheric pollution from the industrial centers near Irkutsk and Ulan-Ude and which is also influenced by the large Baikalsk cellul ose factory. At the northern basin, pollution is only detected at the inflow of the Tiya River, where the dumping of debris from the constru ction of the Baikal-Amour railroad results in high concentrations of F e-rich particles.