## 2 Geotectonic Setting of the Study Area  
The study area comprises the Manzai Ranges, the westernmost extension of the Trans Indus Ranges surrounded by the densely populated towns of Tank, Bannu, and Jandola in the south, northeast, and northwest, respectively. This represents the youngest mountain segment of the active frontal thrust in the western Himalayas and constitutes the Tertiary Siwalik sediments all along its map trace [18; 27]. The major structural elements of this fold-thrust belt are the Khirgi Thrust, Jandola Thrust, Manzai anticline, Jandola anticline, Khirgi anticline, Kundi anticline, and Jandola syncline (Figure 2a). The Khirgi Thrust has truncated the doubly plunging Kundi and Khirgi anticlines in the core, while the Jandola anticline is disrupted by the Jandola Thrust along its map trace [28]. The MFT, locally known as the Khirgi Thrust, places the older Chinji and Nagri Formations over the younger Chaudhwan Formation in the Tank recess. Younger alluvial surfaces concealed the fault trace, and the frontal thrust is recognizable only in a few sections. The northwest-southeast oriented compression initiates the formation and development of east-verging and northwest-dipping thrusts, showing an eastward advance of the tectonic deformation [29]. Laterally, it merges with the transpressional Pezu transfer fault system along the Tank recess in the east. The western boundary is represented by an obducted Waziristan Ophiolitic Belt (WOB) or Melange zone. In contrast, the northern and southern boundaries are marked by the transpressional Kurram Thrust (KT) and Suleiman Fold-and-Thrust belt (SFTB), respectively [27; 28]. The hanging wall of the thrust sheet has a hectometric scale anticlinal and synclinal structures, showing gentle dips of \(\sim\)20\({}^{\circ}\)-45\({}^{\circ}\). Structural complexity increases towards the Melange zone to the west, where the Manzai Ranges merges with the SFTB. The surface geology implicates a thin-skinned deformation style representative of compressional tectonics (Figure 2b). These thrusts join a basal detachment at a depth of 8.5 km [28]. The drainage network flows perpendicular to the major structural lineaments, eroding the quaternary alluvial deposits. The study area has low topographic ridges of sandstone interbedded with claystone and conglomerate beds of the Siwalik Group (Pliocene) [27]. Most of the quaternary deformation associated with the frontal thrusts has modified alluvial fans' geometry, terraces, and boulder deposits. The seismicity pattern is uniformly distributed along the range front thrust with tens of events \(<\)5 Mw (Figure 2a). However, a few shallow earthquakes with magnitudes of 6.3 (16.3 km deep) and 5.8 (10 km deep) that occurred in the Kohat Fold-Thrust belt (1992) and eastern Salt Range (Jhelum Fault) (2019) were more destructive, claiming the lives of dozens of people [30; 31]. Figure 2: **(a)** Shuttle Radar Topography Mission (SRTM, 30 m) digital elevation model (DEM) showing the geotectonic setting of the western Himalayas Fold–Thrust Belt in the TIR. Earthquake data were acquired from the Pakistan Meteorological Department (PMD) and the United States Geological Services (USGS). Structures are modified after [PERSON] and [PERSON] [32]. The focal mechanism solution (FMS) of earthquakes are from Khwaja and Monalsia [33]; (**b**) and 2D seismic interpretation of profile XX\({}^{\prime}\) modified after [PERSON] [28]. The northwest–southeast oriented seismic line cuts across almost all the perpendicular to the major structural elements. This shows the cross-sectional geometry of the Jandola syncline, Jandola Fault, Khrigi anticline, Khrigi Thrust, Manzai anticline and Blind Manzai Fault. These structural elements are dipping northwest and show southeast presence. Stratigraphic units identified on seismic lines are Pleistocene and younger, while Eocene and older age rocks are undifferentiated and are shown as a single unit.