Morphotectonic Studies of Ghaggar Basin in the Northwestern Frontal Part of the Himalaya Based on Remote Sensing and GIS Techniques

The sub-Himalayan zone of the Himalaya is bounded by the Main Boundary Thrust (MBT) in the northern side and by the Himalayan Frontal Thrust (HFT) in the southern side. HFT is the youngest major tectonic boundary of the Himalaya, separating the Siwalik Hills from the Indo-Gangetic plains. The HFT and Piedmont fault make the densely populated foothill region vulnerable to seismicity. A morphotectonic study of active faults and frontal anticlines was carried out near the Ghaggar basin along the NW part of the Himalaya. To investigate morphotectonic setup during tectonic deformation, spatial imagery and morphometric parameters extracted from DEM were used along with field investigation. The analysis divulges an important active tectonic setting of the Siwalik foothills, which governs the morphology of the Ghaggar basin and fluvial processes in the area. Variations in the topographic pattern and the interaction of the river drainage system with faults and folds were measured to describe the evolution of tectonic landforms. Drainage pattern development, drainage basin asymmetry young stage of hypsometric curve, active mountain fronts and vigorous down cutting of river indicate active anticline growth. This active fold growth is advanced by the movements along the blind thrust system of the HFT. Morphotectonic evidence such as fracture, fault scarp, river terraces, and active anticlines during field investigation further confirms the recent tectonic activity due to fault-propagated fold growth.