
Abstract
The Garab manganese deposit is located in the 36o 11' northern latitude and 51o 08' eastern longitude, 2.5 Km away from northeast of Garab village of the Taleqan area. The deposit has occurred in the sandy limestone and tuffic sandstone of Oligo-Miocene. The deposit is stratiform sedimentary type. The aim of projects is to explore the Oligo-Miocene layers of Taleqan area in the Marzanabad sheet for this type of manganese deposits.
The area belongs to the Alborz Mountains with Cenozoic rock units including the Karaj volcano-sedimentary formation. The Oligo-Miocene rocks are the second important unit is the area. The manganese bearing rocks have occurred in the area as stratiform deposit within sandy tuff, lenticular ore body in the tuffic limestone and disseminated ore in sandstone with laminar texture. The ore textures are laminar, disseminated, nodular, and colloform.
The ore bearing layer in the Garab deposit is between 30 and 100 Cm thick that mostly is averagely 50 Cm. The layer is continuing for 500 m. 500 m toward south, another manganese-bearing layer that is 5 to 25 Cm thick parallels the Garab deposit and extends for 2 Km. 68 samples were taken for various analyses. Ore minerals include pyrolusite, psilomelane, brownite, hausmannite, cryptomelane, hauerite, manganite, coronadite, magnetite, and goethite. The geochemical data shows that the MnO grade ranges between 30 to 83%. B and Ag have also high grades and can be exploited as byproducts. Other parts of this unit may contain similar type deposits.