Alluvial soil in India is most likely found in the Indo-Gangetic plains that stretches across almost all of eastern and northern India. They are named after the two rivers that drain the plain: the Indus and Ganges rivers.
Alluvial soil is particularly productive, fertile and rich in nutrients like potassium. It occurs only around rivers and riverbeds when the rivers flood and leave behind soil deposits when the waters recede. Before the silt and soil cements over time, it is called alluvium. After it solidifies into a more rocky formation, it is called an alluvial deposit. The Indo-Gangetic plains are the world's largest area of uninterrupted alluvium.