Exploration of abandoned Pb-Zn mines in Mianeh, Azarbaijan-e Sharqi Province
Executive: Eng. Talebi-Rad
Zarkuh Exploration Consulting Engineers
By: Reza Esfahani, Reza Nozaem, Kazem Qolizadeh, Somayeh Bokharaie, Mina Saen, Ahmad Same, Karim Rezaian, Hojat Kamvar, Farhad Rezaie, Hamid Rahmani, Keyhane Kosari,
The study area is located in the 1:100000 sheet of Hashtjin that has a long history of lead-zinc mining. The available abandoned mines include Senjedeh, Shahali Beiglu, and Khalaf. The alterations in the area and these mines propose the possibility of a porphyry structure in the area. The aim of project is to assess the lead-zinc mineralization is these mines in relation to metallogeny and geology. 1:25000 geology map was prepared for 100 Km2. The project started after a contract between the Zarkuh Exploration Consulting Engineers and IMARCO at 2008.
To prepare the 1:25000 map, at first aerial photographs (1:40000) of the region was studied. After drawing the contacts, faults and features, field tracks were determined. To obtain a better distinction among units, saterlite data were used for central and eastern portion, between Senjedeh and Shahali Beiglu mines. The base map was 1:25000 topography map of NCC.
The prepared geology map is 105 Km2 wide. During filed works, 60 samples were taken from rock units for detail study and petrology. Most of them studied macroscopically. Most of the study area consists of Eocene sedimentary-volcanic rocks that show intensive alterations especially around Mandejin and Senjedeh villages. The flanks of the Qezal Ozan and Ozun Darreh rivers are covered by alluvial deposits of Holocene. There are small exposures of intrusive rocks in the study area.
Reverse faults are between 5 to 30 Km long and strike NW-SE that propose the Paloegene-Neogene compressional regime in the area. Strike slip fault and dykes along NNE-SSW especially in the Shahali Beiglu mine are associated with mineralization.
Mineralization in the Senjedeh mine occurred along the fault zones as malachite and azurite. Due to intensive alteration in the Mendejin area, measurable fault structures are rare, but they are significant in the satellite images and geophysical data. Comparison of these lineaments with alteration and mineralization displays the influence of Paleogene-Neogene faults and sub-volcanic bodies in the areal mineralization. Visit from Shahali Beiglu showed the importance of lithologic control in mineralization. So the controlling factors of mineralization include faults, fractures, and lithology. Fractures in the basalt prisms and dykes contain galena, pyrite, chalcopyrite, malachite and azurite. Tunnels in the Shahali Beiglu also follow this trend. The control of mineralization by lithology is observable in the western end of Shahali Beiglu mine, where the basalt prisms exist.