The main difference between the alluvial soils of northern plains and of coastal plains is that the former mainly due to silt deposited by Indo-Gangetic-Brahmaputra rivers where as the latter is formed due to wave action.The former occur along the Indo-Gangetic-Brahmaputra plains where as the latterr occur at in deltas of the Mahanadi, the Godavari, the Krishna and the Cauvery,