Abstract Aliabad-Morvarid iron-apatite prospecting area is located in southeast of Zanjan, Tarom mountain range, northwest Iran. The exposed rocks are Eocene andesite, trachyandesite and basalt (both lava and pyroclastic). Oligo-Miocene quartz-syenite, quartz-monzonite, monzonite and monzogranite intrude the volcanic rocks. Trace and REE chemical composition of the intrusive rocks indicate that they were emplaced in a volcanic arc setting. Mineralization is found mainly as vein, stockwork and hydrothermal breccias. The geometry of the faults controls the shape of the mineralization. Most of the veins are parallel. Paragenesis involves magnetite, apatite, pyrite, chalcopyrite and secondary ones are hematite, malachite, azurite and goethite. The size of apatite crystals is variable of some mm to more than 20 cm. Important alteration types are: argillic (illite, kaolinite and montmorillonite), sericitic, silicification, potassic, tourmalinization, epidotization, actinolitization and carbonate. The REE distribution patterns of apatite and magnetite samples from the area are similar to those of subvolcanic rocks. Spatial distribution of intrusive rock; type and geometry of alteration; and style, location and mineral paragenesis all indicate that the intrusive rocks are the source of mineralization. The REE patterns of Aliabad-Morvarid mineralization show similarities with Kiruna type magnetite deposits; therefore, it can be classified as a magnetite-apatite Kiruna-type deposit.

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