Fig. 4: Two scenarios proposed for the Indo–Eurasian convergence.

a, Model A: the Great Indian continent model⁵⁵ where the long-term large-scale erosion of the passive margin produced large amounts of sediments whose subduction led to the acceleration of India–Eurasia convergence at 65 Ma. b, Model B: the Great Indian Basin model^14,55; same as in model A, except that a pull-apart basin may have developed within the Indian continent before the subduction of the northern passive margin. Schematic showing three phases during the convergence between India and Eurasia. c, The first phase of convergence that was accompanied by limited shortening due to normal plate coupling. This had been operating since Late Cretaceous following the initial subduction of the Neo-Tethys Oceanic plate that was covered by limited pelagic sediments. d, The second phase of convergence that was accompanied by strong extension of the overriding plate and rapid plate convergence due to the lubricating effect of the subducted sediments. This occurred during the Late Cretaceous to Early Cenozoic and was caused by subduction of thick terrigenous sediments derived from the northern Indian passive margin. e, The third phase due to the initial collision between India and Eurasia followed by slab breakoff. The velocity of the subducting plate would have decreased significantly due to the loss of slab pull. This phase of convergence was accompanied by strong shortening due to enhanced plate coupling. CC, continental crust; SCLM, subcontinental lithospheric mantle. a,b, Figures adapted with permission from ref. ⁶⁰, The American Journal of Science.