NEW ISOTOPIC DATING INFORMATION IN IRAN AND ITS GEOLOGICAL INTERPRETATION

The ages of 3 main ophiolites in Iran are separately 1 406±13Ma, 1 034±6Ma and 1 032±3 6Ma, 912±6Ma, which are all older than their wall rock and represent the ages of original areas. It means they are cold intrusions. The age of Qareh Darreh ophiolite in Takab is 33 9Ma, which may be the intrusion time of the last plate convergence. The Zircon age of Doran alkali feldspar granite near Zanjan is 960±15Ma, which is the age of the oldest basement in Iran until now. The age of Gasht Rudkhan granite in Rasht is 417Ma, which represents the age of the crust movement of Alborz Mountains in a long time lifting and denudation. In Iran, the main Fe deposits are formed in 476—461Ma and the main Pb Zn deposits are formed in 198 53—233 42Ma.