Structural Controlled Metallic Mineralization in Lower Swat, NW Pakistan

The study presents the results of structural, hydrothermal, magmatic, and metamorphic control on metallic mineralization across the Kashala syncline, Loe Sar Dome, Kotah Dome, and the Main Mantle thrust melange zone in Lower Swat, NW Pakistan. Lower Swat rocks preserved three well defined D-1, D-2 and D-3 deformation and metamorphic events. S, foliations related to D-1 preserved in garnet are truncated by the main S, crenulation cleavage. D-2 related S(2)and L-2(2) that dominates the Swat valley predated the Kotah and Loe Sar domes/metamorphic core complexes culmination because the latter controls the dip pattern of the D, related structures. D-3 and L-2(3) intersection lineation microscopically and mesoscopically overprint D-2. These multiple structures are constrained to gain insight into the structural traps in the form of shear zones, faults, boudinage necks, fold limbs, saddle reefs, contacts and veins to drop fluids laden Au, Ag, Cd, Co, Cr, Ni, Zn, Ph and Cu metallic ores. These ores are noticed along four zones of concentration. The Marghazar Concentration Zone lies at the Nawagai Overturned Anticline saddle reef, the Marghazar Concentration Zone 2, lies at the Ilam Overtw-ned Syncline, Similarly, Intrusive contacts of the Tertiary Swat Tourmaline Granite (STG) with the Marghazar Formation and Swat Granitic Gneisses (SGG) contain high concentration of Cr, Ni, Zn, and Cu with moderate Ag, Cd, Ph and Co. A quartz vein at the 'lam Overturned Syncline and a mineralized zone south of the Loe Sar Dome (LSD) at the Ghundai anticline contain the highest concentration of gold. Metals data collected from the shear zone within the Marghazar Formation is markedly depleted in Co, Zn, Cr, Ni, Cu and Pb as compared to the average concentration of these metals in the remaining Marghazar Formation.