Sulfur isotope variations of sulfide minerals in porphyry systems of the Meiduk cluster, Kerman Cenozoic magmatic arc, southeastern Iran

Sulfur isotope data on pyrite, chalcopyrite and molybdenite in the A, B and D type veinlets in porphyry systems of the Meiduk cluster, located in northwestern part of the Kerman copper belt, show that these systems have near zero δ34S values. Sulfur isotope composition for the Chah-Firouzeh and Iju deposits and Serenu, God-e-Kolvari and Kader prospects is from -1.4 to .5 (average .31), -1.3 to .1 (average .07), .1 to .4 (average .87), -1.5 to .2 (average -0.1) and -4.1 to (average -1.04), respectively. These results suggest a magmatic source for sulfur. Also, limited range of isotopic variations and analogous isotopic composition for the three types of veinlets reveals that with evolution of the hydrothermal system, no significant changes occurred in the primary and relatively homogenous source of sulfur. Comparison between the data for the Meiduk cluster with available data from other deposits in middle and southern parts of the Kerman belt suggested that in porphyry systems of the northwestern, and to some extent southern parts, of the Kerman Cenozoic magmatic arc, sulfur was provided by a mafic magma originated from metasomatized subcontinental lithospheric mantle (SCLM) which was affected by assimilation with continental crust; while in the southern parts, processes related to subduction and fluids from seawater and associated sediments had a major role in their sulfur isotope composition.