تعیین سن توده های نفوذی وکانه زائی مس پورفیری در منطقه علی آباد و دره زرشک یزد به روش K-Ar و ۴۰Ar/۳۹Ar

Darreh-Zerreshk and Ali-Abad are two relatively small porphyry copper deposits in Yazd Province in central Iran. They are located within the central Iranian volcano-plutonic belt. This paper discusses the K¤Ar and ^۴۰Ar/^۳۹Ar geochronology of plutons and alteration phases associated with the Darreh-Zerreshk and Ali-Abad deposits. The deposits are spatially associated with igneous complexes that consist of granites intruded by relatively more mafic intermediate granitoids, which are the carriers of mineralization. An orientation study using K/Ar dating on ۶ whole rocks suggested that the pre-ore granites are Oligocene (ca. ۳۱-۲۸ Ma) in age, whereas the intermediate plutons are Miocene (ca. ۱۳-۱۶ Ma). Nine samples of biotite and sericitized whole-rocks from drillcore within the mineralized and altered zones in both deposits were dated by multi-stage degassing ^۴۰Ar/^۳۹Ar, yielding well defined plateaus of ca. ۱۶ Ma, confirming that the age of porphyry copper mineralization in the Darreh-Zerreshk and Ali-Abad deposits is Miocene.

کلید واژه ها: یزد