Geomorphometric features and tectonic activities in sub-Himalayan thrust belt, Pakistan, from satellite data

The sub-Himalayan thrust belt is an active thrust wedge which progresses southward over the north-dipping Indian plate. The north–south compression resulted in severe deformation of sedimentary rocks in this belt. Distinct thrust geometries and topography have evolved under the interaction between tectonic and erosional environments. To better understand the relationship between tectonics and topography, A Digital Elevation Model (DEM) derived from Shuttle Radar Topography Mission (SRTM) data was used to extract the geomorphic and drainage features. Based on comprehensive analyses of topographic relief, drainage density, and drainage patterns, nine topographic units were identified. The thrust wedge was divided into three physiographic assemblages with apparent lateral variations. These units match up with the interpreted main structures from the Landsat Enhanced Thematic Mapper Plus (ETM+) images and published geological maps. The relationship between geomorphometric features and tectonics indicates that structural activities primarily control the topography in the sub-Himalayan thrust belt. Topographic features are indicative of tectonics in the young tectonic regions with low elevation.