Focal mechanism studies of Kohat and northern Potwar deformed zone (NPDZ), Pakistan
Abstract
Kohat Plateau and Northern Potwar Deformed Zone (NPDZ) are the parts of the foreland zone of NW Himalayan Fold-and-Thrust belt, which is seismically very active. Using the earthquake data of international as well local networks, seismicity maps of the area have been prepared Focal mechanism solutions of nine events, for the period of1970-1996have been carried out. The dominance of strike slip faulting over the thrust faulting (i.e. 7 are left lateral strike slips while two are thrusts) supports the conclusion of previous workers that this area of convergence is undergoing a kinematic change. P-axes i.e. the axes of maximum compresses stress orientations are both in NW-SE and NE-SW directions indicating a complex pattern of deformation, Indications are that basement is most likely involved in the deformation.
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