Geology, Petrographical Features and Ore Mineralization of Volcanic Hosted Iron Ore Deposit in the Mashki Chah Area Chagai District, Balochistan, Pakistan

Abstract

The Mashki Chah iron ore deposits are located in the western Chagai magmatic belt and hosted within andesitic rock units in the Late Cretaceous Sinjrani Volcanic Group. Geometry, morphology, and structure of iron ore have massive, thin to thick-bedded and veins type of iron. The major ore type including magnetite as primary mineralization of iron ore and hematite, siderite, goethite, and limonite are secondary mineralization of iron ore. Petrographically, the iron ore is hosted within the basic to the intermediate type of units (Basaltic Andesite, Andesite, and Dacite) within the Late Cretaceous Sinjrani Volcanic Group. Major constituents of basaltic andesitic units are composed of clinopyroxene and amphibole with minor constituents of quartz. Andesitic units consist of plagioclase, hornblende, k-feldspar, quartz and biotite. The dacitic unit is comprised of quartz, albite, k-feldspar, biotite, and muscovite. SEM-EDX and BSE analysis of ore mineralization of iron ore to identify the mineral crystal structure, texture, and elemental composition of iron ore. BSE images indicate the crystal morphology of magnetite and hematite have well-developed cubic and octahedron crystal shapes with a coarse grain texture. Elemental composition is identified by the EDX graph that is indicated the high peaks of Fe and O elements associated with the high peak rock-forming minerals elements Si and O with sub-peaks of Al, Na, K, and Ca and as well as have sub-peaks of ore-forming mineral elements are include a Cu, Ag, Ti, and Sn. The total iron reserve in the deposit area is approximately about 45 to 50 million tons and an average percentage of magnetite is 86.16% and hematite is about 69.40 %. These ore deposit has significant value for economic purpose and as well as economically the Mashki Chah iron ore deposit is viable for iron ore mining.