Sulfur Isotope Studies in the Zinc-Lead Mine San Vicente, Central Peru

The stratabound Zn-Pb deposit of San Vicente, presently the largest zinc producer of Peru, is located about 300 km east of Lima in the tropical rain forest of Central Peru (Schulz 1971; Levin and Amstutz 1973; Fontboté and Gorzawski 1990). The San Vicente deposit appears to be associated with certain dolomitic facies within a transgressive carbonate sequence (up to 2000 m thick) in the eastern part of the Upper Triassic-Liassic Pucará Group. The ore-bearing dolomites belong to a peritidal facies belt that forms a transition between detrital-evaporitic sediments at the margin of the Brazilian Shield to the east, and open marine carbonates of the central Pucará to the west. Along this facies belt, that is recognized over a distance of at least 200 km from north to south, are a number of nonexploited ore deposits and occurrences. These collectively belong to a Mississippi Valley-type province in the eastern Pucará, whose economic significance at present is not well known (Fontboté this Vol.).