Tectonic imprints of the Hazara Kashmir Syntaxis on the Northwest Himalayan fold and thrust belt, North Pakistan

Abstract

Constraints from microscopic to mesoscopic structures and their relationship with the map scale macroscopic structures indicate a succession of two dominant deformation events for the rocks exposed in the western limb of the Hazara Kashmir Syntaxis. Regional scale NNE–SSW trending macro to meso scale fold axes and faults are distinctly deflected top to the NW with sinistral shear sense in the apex region of the Hazara Kashmir Syntaxis. Detailed analyses of micro, meso, to macro scale folds axes, stretching lineations and intersection planes indicate dominate NNE–SSW trending structures. The comprehensive study of en-echelon gash veins and NW verging asymmetrical to overturned folds with SE dipping axial planes show top to the NW sinistral shear sense. The gash veins overprint SE and SW plunging lineations and bedding across the region. The en-echelon gash veins and asymmetric to overturned limbs of the NNE–SSW trending folds that dominate the area developed during the last stage intense tectonism associated with the Hazara Kashmir Syntaxis within the Indian Plate. The Hazara Kashmir Syntaxis did not rotate the dominate NNE–SSW trending structures in the study area, due to shearing and rotation along the same axis.