Mineralogy and geochemistry of host rocks of in the Jalal Mn ore Deposit ( South of Qom)
Subject Areas :Mansore Mahdavi 1 , محمد Yazdi 2 , M.H Emami 3
1 - کارشناس ارشد زمین شناسی اقتصاد
2 - دانشیار دانشگاه شهید بهشتی
3 - دانشیار دانشگاه آزاد اسلامی واحد اسلامشهر
Keywords: Qom, Geochemistry, Mineralogy, volcano-sedimentary rocks, Jalal Mn-deposit,
Abstract :
Jalal Manganese ore is located in the southwest of the Qom. The area is located in Uromieh-Dokhtargeological zone of Iran. The base and host rock of the area include Eocene volcanic rocks such as basalt,andesite, trachyte, rhyolite, andesite-basaltic lava and spillitic lava. The lavas are more pillow types. Theyounger andesite-basaltic dykes have been intruded to these volcano-sedimentary rocks of the area.TheMn- mineralization was hosted in the volcano-sedimentary rocks of the area. Hangingwall and footwall ofore are andesite-basaltic lava and spillitic lava. The ore mineralization was hosted as vein type withinfaults, joints and fractures. The main direction of ore mineralization is NW-SE in the several parallellayers. These layers have been known as A, B, D ore layers in the Jalal area. The surface outcrop of orelayers is about 2km and have been cut by several local faults, mainly in NW of the area. The new drillingsshow that the dip and direction of the ore layers have been changed in the dipper parts mainly to the NE.The ore minerals are mainly pyrolusite, Psilomelane, with Mn oxides and non-ore minerals are mainlycalcite and quartz. Field survey, geochemical and mineralogical studies show that the mineralization isvein epithermal type.