The studied area is located in northwest of Iran, in central Iran zone, western Alborz sub-zone in south of metallogenic zone of Tarom-Hashtjin. Exposed rock units of this area generally include Eocene volcanic rocks (the lava flows and pyroclasts belonging to Karaj formation) and Oligomiocene granitoid intrusive bodies. Intrusive bodies of the area petrographically have a composition of granite, syenite and monzonite and are mostly metaluminous. Dual characteristics of these intrusives (for example, behaviour of elements like Rb, P and Ga/Al, Y/Nb, K/Na, FeO/Fe2O3, Rb/Nb ratios and A/CNK molar ratios and also ACF and A/CNK-Fe2O3+FeO diagrams) some of which are consistent with I nature and some with S and even A ones, show that they are among hybrid granitoids and in terms of tectonic setting lie in range of WPG ones. According to Rb/Sr, Zr/Hf, K/Rb ratios, the granite melts forming the mentioned bodies, are not extremely evolved and have not undergone the post magmatic activities to lead to mineralization. Sm/Eu, Rb/Ba ratios and also behaviour of Rb, Ba and Sr elements of the mentioned granitoids show that they are similar to the average granitoids irrelevant with Li, Be, Sn, W and Ta deposites and they are set in range of barren granitoids but regarding Cu are partially fertile. |