Abstract

The Suối Thầu Deposit is located in the northeast part of the Phan Si Pan Subterrane. The copper mineralization is associated with a unknown in age tonalitic intrusion. Intense K-silicate alteration associated with quartz stockworks occurs in the center of the intrusion and is surrounded and overprinted by propylite alteration. Ore minerals include chalcopyrite, pyrrhotite and pyrite disseminated in alterated rocks or occurs within sulphide quartz veins. Structural geology and ore deposit geology investigations suggest that the Suối Thầu Deposit belongs to the copper porphyry deposit. The deformation characteristics of the host rocks and the field observations suggest that the copper mineralization in the deposit were formed prior to the initiation of left-lateral shearing along the Ailao Shan - Red River Shear Zone.