Sunnyside: A Vertically-Preserved Porphyry Copper System, Patagonia Mountains, Arizona

The Patagonia Mountains are located 65 miles south of Tucson, Arizona along the northwest-trendjng belt of porphyry copper deposits extending from Lhc Nacozari-La Caridad area in Sonora, Mexico to the Sacaton deposit in central Arizona (Figure 1). The areal geology is dominated by a large, differentiated, locally porphyritic, Laramide-age intrusion of quartz monzonite to granodiorite composilion (Figure 2) which has been dated at 58-64 my by K-Ar methods (Simons, 1974). Wall rocks are diverse, ranging from Precambrian granitic rocks to late Cretaceous volcanic rocks (Baker, 1961; Simons, 1972 and 1974)....