Table 1.

Geological hypotheses for the collision between the Indian subcontinent and Asia in regard to timing and sequence of events

Hypothesis	Plate positions	Time period	Ref(s).
Traditional view	One direct collision process between India and Eurasia	Early to Middle Eocene (50 Ma)	42
Ali and Aitchison’s hypothesis
Acton’s India model	India collides with an intraoceanic island arc, allowing for terrestrial connections; NE corner of the Indian subcontinent making a glancing contact with Sumatra, and subsequently with Burma	Early Eocene (55 Ma)	10, 12
	NE India is in contact with western SE Asia and might have been subaerially exposed	Middle Eocene–Late Eocene (55-34 Ma)
	Continent–continent collision	Late Eocene–Early Oligocene (34 Ma)
Schettino and Scotese's India model	No connection; India ∼1,000 km further to the west of SE Asia	Early Eocene (55 Ma)
	No connection; NE India submerged	Middle Eocene–Late Eocene (55–34 Ma)
	Continent–continent collision	Late Eocene–Early Oligocene (34 Ma)
Van Hinsbergen’s hypothesis	Collision of a Tibetan–Himalayan microcontinent/terrane with Asia	Early Eocene (52 Ma)	16
	Subduction of the largely oceanic Greater India Basin along a subduction zone at the location of the Greater Himalaya	Middle Eocene–Late Oligocene (52–25 Ma)
	Final Indian–Asian collision	Late Oligocene–Early Miocene (25–20 Ma)