PETROGENETIC STUDY OF SULPHIDE MINERALIZATION AND ASSOCIATED MINERALS IN MUHAMMAD KHEL AREA DISTRICT NORTH WAZIRISTAN, KP, PAKISTAN

Abstract

Muhammad Khel area lies in North Waziristan district of Kyber Pakhtunkhwa province of Pakistan and falls in the Survey of Pakistan Top sheet No. 38 H/13. The Muhammad Khel and the surrounding areas comprise mainly ophiolites, known as the Waziristan ophiolite complex. A complete ophiolite sequence is exposed in the area. The area contains chromite, iron, manganese and copper deposits. Pillow and the brecciated basalts of the complex contain chalcopyrite, bornite, malachite and pyrite which occur mainly along fractures, veins and stockwork deposits. The presence of gossans in the area indicates that these deposits are formed due supergene enrichment activity. In thin section study, intensive chloritization and at places silicification are noticed along fractures and veins due to hydrothermal activity. The groundmass also shows chloritization after alteration of pyroxenes and plagioclase in basalts. The XRD analysis confirm copper sulphides ores as chalcopyrite and pyrite and goethite, jarosite and hematite in gossans ore samples. The presence of copper sulphide in brecciated and fractured oceanic crust basalt indicates that Muhammad Khel sulphide deposits formed due to deep circulation of oxygenated sea water along fractures passing through submarine pillow lavas, therefore, termed hereby as the volcanogenic massive sulphide deposits (VMS). These deposits are formed during ocean floor spreading activity. The VMS deposits of the investigated area can be correlated with Cyprus type sulphide deposits of the Troodos ophiolite complex, which shows similarity in lithology, tectonic setting and mode of mineralization of the sulphide ores and related minerals.