Which plain is formed by the river Ganga Brahmaputra and Indus?

The northern plains are formed by the alluvial deposits brought by the Indus, the Ganga and the Brahmaputra rivers. These plains extend approximately 3,200 km from the east to the west. The average width of these plains varies between 150-300 km. The maximum depth of alluvium deposits varies between 1,000-2,000 m. 

Further Reading:

• Physiographic Division of Great Plains of India
• NCERT Notes: Geography – OUR COUNTRY – INDIA

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