Timing of mineralization and exhumation processes at the Sar Cheshmeh and Meiduk porphyry Cu deposits, Kerman belt, Iran

摘要

This study utilizes zircon U-Pb, zircon (U-Th)/He and apatite (U-Th)/He geochronology to constrain the thermal histories of the Sar Cheshmeh and Meiduk porphyry Cu deposits in the Kerman belt, Iran. Hydrothermal Cu deposition at Sar Cheshmeh occurred within a 160,000 year period following magma emplacement at 13.6 Ma. The deposit was emplaced at 3-4 km depth and exhumed to shallow crustal levels about 7 million years ago. The Meiduk deposit was emplaced in a shallower, subvolcanic environment at 12.5 Ma and experienced relatively rapid cooling such that the zircon U-Pb and (U-Th)/He ages are identical. A similar observation was made at the Abdar Cu-Au prospect in the Kuh-e-Masahim volcano indicating that zircon (U-Th)/He can be used as a geochronometer for rapidly cooled volcanic rocks.