<P> Parts of Afghanistan are sometimes included in Indian subcontinent as, states Ira M. Lapidus--a professor of History, it is a boundary territory with parts in Central Asia and in Indian subcontinent . The socio - religious history of Afghanistan are related to the Turkish - influenced Central Asia and northwestern parts of the Indian subcontinent, now known as Pakistan . Others state Afghanistan being a part of Central Asia is not an accepted practice, and it is "clearly not part of the Indian subcontinent". </P> <P> The term Indian subcontinent also has a geological significance . It was, like the various continents, a part of the supercontinent of Gondwana . A series of tectonic splits caused formation of various basins, each drifting in various directions . The geological region called "Greater India" once included Madagascar, Seychelles, Antarctica and Austrolasia along with the Indian subcontinent basin . As a geological term, Indian subcontinent has meant that region formed from the collision of the Indian basin with Eurasia nearly 55 million years ago, towards the end of Paleocene . </P> <P> Geologically, the Indian subcontinent was originally a part of a "Greater India", a region of Gondwana that drifted away from East Africa about 160 million years ago, around the Middle Jurassic period . The region experienced high volcanic activity and plate subdivisions, creating Madagascar, Seychelles, Antarctica, Austrolasia and the Indian subcontinent basin . The Indian subcontinent drifted northeastwards, colliding with the Eurasian plate nearly 55 million years ago, towards the end of Paleocene . This geological region largely includes Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan and Sri Lanka . The zone where the Eurasian and Indian subcontinent plates meet remains one of the geologically active areas, prone to major earthquakes . </P> <P> Physiographically, it is a peninsular region in south - central Asia delineated by the Himalayas in the north, the Hindu Kush in the west, and the Arakanese in the east . It extends southward into the Indian Ocean with the Arabian Sea to the southwest and the Bay of Bengal to the southeast . Most of this region rests on the Indian Plate and is isolated from the rest of Asia by large mountain barriers . </P>

What is delta name some deltas of indian subcontinent