Geomorphic evolution of the Piedmont Zone of the Ganga Plain, India: a study based on remote sensing, GIS and field investigation

Abstract

The geomorphic evolution of the Piedmont Zone of the Ganga Plain is not well understood, since the identification of various morpho-tectonic features in the field is very difficult because of the thick forest cover, extensive anthropogenic modifications in the landscape and easily reworkable gravels. Interpretation of satellite imagery, Digital Terrain Models (DTMs) and field data has helped in identification and mapping of various morpho-tectonic features in a hitherto unstudied part of the Piedmont Zone and the adjoining areas in north-western Ganga Plain, India. The Piedmont Zone has formed as a result of laterally coalescing alluvial fans of variable dimensions and talus deposits, and is traversed by active faults and thrusts. The variable subsidence rates along the basin margin (i.e. the Himalayan Frontal Thrust) and climatic events have controlled the accommodation space and basinward progradation of alluvial fans. The landscape of the Piedmont Zone is presently being continuously modified by the ongoing tectonic movements and seasonal climatic variations.