Indian Plate
The basin overlies a series of Indian Plate depressions and ridges, that have also been used to subdivide the foreland basin. The rock units that make up the Indian plate vary dramatically along the length of the basin, changing from Proterozoic Mobile Belt rocks, to Archean Craton, and Proterozoic Vindhyan Supergroup sedimentary rocks. These Indian Plate rock units extend under the foreland basin and have been correlated to a series of depressions and ridges underneath the foreland basin. As the Indian plate has flexed (bent) under the Eurasian plate, the depressions and ridges have acted as flexible and stiff areas respectively, influencing the thickness of the foreland basin fill.