Geology and mineralization of the Candelaria-Punta del Cobre Fe oxide Cu-Au deposits, Chile

There is a 5km wide and 20km long belt of Fe oxide Cu-Au deposits along the eastern margin of the coastal batholith near Copiapó, Chile. It includes the Candelaria deposit and a group of middle and small sized deposits in the Punta del Cobre district, which is located about 3km northeast of the Candelaria mine. It is estimated that the amount of copper ore resources in the belt is 700-800 million tons at 1.0 percent Cu. The ore minerals are mainly chalcopyrite, pyrite, magnetite, hematite. The ores occur in veins, breccia and stringer bodies. The orebodies are hosted mainly by volcanic and volcaniclastic rocks of the Punta del Cobre Formation. Most of the larger orebodies in the belt are situated along NW to NNW trending high-angle brittle faults which intersect the contact between massive volcanic and volcaniclastic rocks. The ores occur mainly in zones with biotite-K feldspar±calcic amphibole±epidote alteration at Candelaria. In the Punta del Cobre district, alteration associated with ores in the deeper parts of the deposits is similar to that at Candelaria, whereas at their shallow levels ores occur in biotite-K-feldspar or albite-chlorite±calcite alteration zones.