New data on the age of ore formation in the unique Katugin rare-metal deposit (Aldan Shield)

The Katugin composite rare metal (Ta, Nb, Zr, Y, and REE) deposit is one of the largest Precambrian rare metal deposits associated with alkalic granite in the world [ 1]. It is located at the southern margin of the Chara- Olyokma block of the Aldan Shield in the immediate vicinity of the southern boundary of the Stanovoi Structural Suture, which separates this block from the Selenga- Stanovoi superterrane of the Cen tral Asian Fold Belt (Fig. 1). The deposit is associated with two small (3 and 18 km2) bodies of alkalic granites of the Katugin Complex, which are confined within the limits of the sublatitudinal Kalakan Tectonic Zone stretching along the southern marginal part of the Palaeoproterozoic Kodar- Udokan depression. The latter is composed mainly of metasiliciclastics of the Udokan Group. The geological structure of the Katugin deposit has been described earlier [3, 4, and others].