Study of the mineralization potential of the intrusives around Valis (Tarom-Iran)

摘要

The study area is located in northwestern Iran in the central Iran zone, specifically the western Alborz sub-zone south of the Tarom-Hashtjin metallogenic zone. The exposed rock units in this area generally include Eocene volcanic rocks (lava flows and pyroclasts belonging to the Karaj formation) and Oligocene granitoid intrusive bodies. The intrusive bodies in the area have a petrographic composition of granite, syenite and monzonite and are mostly metaluminous. The dual characteristics of these intrusives (for example, the behavior of elements such as Rb, P, Ga/Al, Y/Nb, K/Na, and FeO/Fe2O3, the Rb/Nb ratios, the A/CNK molar ratios and the ACF and A/CNK-Fe2O3+FeO diagrams), some of which are consistent with the I nature and others with the S and A natures, show that the rocks are among hybrid granitoids and, in terms of the tectonic setting, lie within the WPG range. According to the Rb/Sr, Zr/Hf, K/Rb ratios, the granite melts that form the aforementioned bodies are not extremely evolved and have not undergone post magmatic activity, which would lead to mineralization. The Sm/Eu and Rb/Ba ratios and the behavior of Rb, Ba and Sr within the aforementioned granitoids show that the rocks are similar to average granitoids unrelated to Li, Be, Sn, W and Ta deposits; they fall within the range of barren granitoids but are partially fertile in Cu.