Significance of Syndepositional Tectonics in Facies Development, Gangetic, Alluvium near Kanpur, Uttar Pradesh

Abstract

Gangetic Plain, an active foreland basin shows N to NE flowing rivers in the southern part, controlled by the basement lineaments; while in the central part most of the rivers flow SE to E, following partly the lineaments developed in response to the Himalayan tectonics. Analysis of the subsurface data in Hamirpur-Kanpur-Unnao region shows that just south of present-day Ganga River, along an E-W trending lineament major change in the alluvial thickness and facies has taken place. It is suggested that earlier (probably Middle Pleistocene) rivers from Peninsular India flowing upto Kanpur, shifted their course southwards, and onlapped by Himalayan rivers and their deposits. It is argued that in 'an active foreland basin, lineaments parallel to orogen may develop, some of them even as gravity faults affecting the basement. These lineaments have a strong control on drainage, and thickness of the alluvial fill.