Gold-Bearing Placer Assemblages in the East of the Siberian Platform: Origin and Prospects Z. S. Nikiforova and A. V. Tolstov p. 1 Evaluation of the Radioecological Situation in the Elkon Uranium Ore District (Aldan Shield) by Field Radiometry Methods P. I. Sobakin, V. E. Usnitsky and Ya. R. Gerasimov p. 26