Postcollisional kinematics in the northwestern Himalayan foreland: Insights from the Kohat Plateau, Pakistan

Abstract Understanding the deformation pattern in the Kohat fold-and-thrust belt (KFTB), Pakistan, is essential for unveiling the postcollisional kinematics of India-Asia interactions, with implications for seismic hazards, drainage reorganization, and edge-driven tectonics. This research provides detailed analysis of Neogene Siwalik Group rocks in the KFTB through rock magnetism and paleomagnetism techniques. The paleomagnetic results of the KFTB exhibit distinct vertical-axis rotations (VARs) for the Siwalik strata representing counterclockwise rotation of 45° ± 2° in its eastern domain (aligning in direction with the compiled paleo-declinations of the adjacent Potwar fold-and-thrust belt) and clockwise rotation of 53° ± 3° in its western domain. The VARs dataset of the northwestern Himalayan foreland suggests that strike-slip deformation is a fundamental factor in reshaping the tectono-stratigraphic framework of this region in Miocene–Pliocene times. Comparing the ongoing interplay of lateral propagation of this region with Riedel shear experiments suggests that the distinct VARs are separated by the principal deformation zone within the KFTB, along which a seismicity profile and drainage divide occur. Additionally, the correlation between geothermal gradient and seismicity in the KFTB indicates decoupling and crustal fragmentation, highlighting mechanical instability and “ball-bearing” tectonics in the northwestern Himalayan foreland.