Neotectonic Study of the Sibi Re-Entrant

The Suleiman Fold-Thrust Belt represents an active deformational front at the western margin of the Indian plate. It is sub-divided into the eastern, central, and western parts. This study focuses on the western part of the Suleiman Fold-Thrust Belt that comprises two parallel NW-SE oriented faults; Harnai Fault and Karahi Fault. These faults have known thrust components; however, there remains uncertainty about the lateral components of motion. I used 2D seismic data to constrain the subsurface structural geometry and the Small Baseline Subset (SBAS)-Interferometric Synthetic Aperture Radar (InSAR) technique using Sentinel-1A datasets to decompose displacement into the vertical and horizontal components employing ascending and descending path geometries. Tectonics of this area were assessed using two geomorphic indices, i.e., Hypsometric Integral (HI) and Valley Floor Width to Height Ratio (Vf). For InSAR datasets, 45 ascending and 45 descending orbit Sentinel 1A images were processed and used to calculate the vertical and horizontal displacement components. InSAR results show that the Karahi Fault has a dextral (right-lateral) movement, with a rate of movement of ~15 mm/year for descending and ~10 mm/year for ascending path geometries. The Harnai Fault does not show any lateral movement. Seismic data support InSAR results that the Harnai Fault is a blind thrust. This suggests that the block between these two faults displays a clockwise rotation that creates the "bookshelf model". Hypsometric Integral (0.44) and Valley Floor Width to Height Ratio (0.53) indices results also indicate that the northern part of the Karahi Fault is tectonically more active than the southern part of the Harnai Fault.