Document Type : Original Research Paper


1 Ph.D., Faculty of Earth Science, Shahid Beheshti University, Tehran, Iran

2 Ph.D., Faculty of Basic Science, Tarbiat Modarres University, Tehran, Iran

3 Professor, Faculty of Earth Science, Shahid Beheshti University, Tehran, Iran


The Fe-Pb Ahangaran deposit, hosted by tuffaceous siltstone of the Early Cretaceous sedimentary sequence in the northern part of the Malayer-Esfahan Metallogenic Belt (MEMB), Iran. Ore mineralization occurred as stratiform and a widespread veinlet zone in the upper part of Lower Cretaceous terrigenous unit (Kc). Four different ore types can be distinguished in deposit include: (1) veinlet (feeder) zone, (2) sulfide-Fe- oxide stratiform ore (3) barite ore and (4) vein ore. Ore minerals in the different ore types are pyrite, siderite, magnetite, galena, barite, chalcopyrite and tetrahedrite and rare minerals are pyrrhotite, arsenopyrite, and freibergiteCarbonatization and silicification are the main hydrothermal alterations in this deposit. The orebodies in the Ahangaran deposit have been replaced by iron oxide minerals in supergene process and have been formed a thick gossan zone. The textural and mineralogical data provide evidence of three stages of mineralization (Early, main and late stage) in Ahangaran deposit. According to evidences such as tectonic setting, type of host rock, geometry of deposit, sulfide-Fe oxide ore types, textures and structures indicate that the Ahangaran deposit is compatible with a sub-seafloor replacement mineralization that has been suggested for some Sedex deposits.


Main Subjects

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