J.R. Spurr 1, an eminent American geologist, designated within the Cordillera and Andes "the great silver channel" that extended from Oregon to Tierra Del Fuega. Several such ore "channels" of Cenozoic and late Mesozoic age had been revealed by the mid-19th century. The Okhotsk-Chukchi volcanic belt (OCVB) controls the "great gold-silver channel" extending for 3000 km. The OCVB is made of late Mesozoic sub-aerial volcanic rocks. With respect to the oceanic margin, it is separated into the inner, outer, and perivolcanic zones (Fig. 1). The complicated structure of basement terranes has determined a great variety of OCVB ore assemblages. Deposits of copper-molybdenum-porphyry formation comprising gold, silver, and platinoids are mostly concentrated in the inner zone of the belt.
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