Abstract

Lulak Abad iron occurrence is located in northwestern part of the Central Iran, 70 km west of Zanjan. Iron mineralization at Lulak Abad occurs as veins, veinlets and lens-shaped bodies. The host rocks are deformed schist units, mylonitized metavolvanites and mylonitized granite. In addition, parts of iron mineralization occur as disseminated in microdioritic rocks. Two deformation events are recognized in the area, ductile and brittle; the main one is ductile. Based on mineralography, oligiste is the main ore which is accompanied with minor magnetite and pyrite. Goethite is a supergene mineral. Quartz and calcite are present as gangue minerals. The ore minerals show vein-veinlet, breccia and open space filling textures. Alteration is restricted to oligist (hematite), silica and calcite alteration parts of the ore zones. Iron mineralization at Lulak Abad is introduced in three stages: 1) The first stage is coeval with the deposition of the volcano-sedimentary units in the area. This stage occurs as stratiform and startabound lens and disseminated magnetite. 2) Stage 2 occurs as oligist- pyrite- calcite veins and veinlets that have discordant relation with respect to the main mylonitic foliation. 3) Stage 3 is distinct mineralization stage and has genetic link with microdioritic rocks. This stage is post metamorphic and deformation events. Field and microscopic studies indicate that iron mineralization in the Lulak Abad occurrence seems to be hydrothermal vein mineralization. Iron mineralization in Lulak Abad occurrence could be used as a model for prospecting and reconnaissance of same iron mineralization in the Central Iran and similar districts of Iran that have similar geological features.