sedimentary basins
Sediment influx into continental margins is particularly important. However, there is a strong contrast between passive and active margins. Indeed the large accumulation of sediments along the eastern largely passive margin of the American continent contrasts with that on the western margin largely active.
The thickness of the sedimentary pile in the Bengal Gulf and the Gulf of Mexico is up to 20km. The close proximity of large topography (the Himalaya) combined with major river systems in the first and the large drainage basin of the Mississipi of the latter explain the large accumulation of sediments.