RELATIONS BETWEEN DIFFERENT TYPES OF TIN MINERALIZATION IN SOUTHERN SIKHOTE-ALIN (RUSSIA)

Two cycles of tin mineralization, Late Cretaceous and Eocene, were est ablished in southern Sikhote Alin. The tin mineralization of the Late Cretaceous cycle was subdivided into two series that developed simulta neously but were related to different magmatic complexes. The first se ries is associated with leucocratic granitoids, whereas the second is related to granitoids of an elevated basicity. The deposits of both se ries are generally closely confined to contacts of granitoids and occu r within the halos of contact hornfels Late Cretaceous. The mineraliza tion processes of both Late Cretaceous series started with the formati on of two complex multimetal ore deposits: (1) greisen-polymetallic an d (2) tourmaline-massive sulfide with manganese minerals. The later de posits of these series are represented by various deposits and are occ urrences of Sn, Pb-Zn, W,Ag-Pb-Zn, and other metals. The Eocene deposi ts occur at some distance from the contacts between granitoids and hor nfels. They are often associated with basic dikes and represented by v eins containing abundant tourmaline or chlorite and subordinate sulfid es. Both Late Cretaceous and Eocene deposits are localized at several depth levels and reveal zonality relative to the contacts of granitoid s and biotization halos.