Question

how were the northern plains formed​

Answer 1

Answer:

Northern Plains were formed by the sediments brought in by three major Himalayan rivers (Ganga, Indus and Brahamaputra) and their tributaries. When these rivers flowed through the Himalayas, they eroded rocks, transported and deposited the smaller fragments of rocks in the foothills of the Himalayas.

Answer 2

Answer:

Formation of Northern Plains:

That basin was filled with sediments from the rivers which came from the mountains in the north and from the peninsula in the south. These extensive alluvial deposits led to the formation of the northern plains of India.