Isotopic evidence for distinct crustal sources of North and South Range ores, Sudbury Igneous Complex

Lead isotope ratios were measured on Fe-Cu-Ni sulphide ores and associated silicate phases from nine mines on the North and South Ranges of the Sudbury Igneous Complex (SIC). These data are compared with the lead isotope signatures of country rocks and shock-melted Sudbury Breccias around the complex. Both ore and feldspar data from the South Range fall along a 1.85 Ga reference line (the age of the igneous complex) and indicate a magmatic …