Thermohaline circulation is the principal driving force of deepwater bottom-currents. The term refers to the movement of water over large distances as a consequence of global oceanic density gradients. This circulation commonly travels at velocities between 2 – 20 cm/s. Note that at this velocity range, considering the general shape of the Shields diagram still holds in these conditions, a flow will only be able to continue transporting finer sediment that is already in suspension but will not be able to erode the same sized sediment once it is deposited. However, flow velocity may be intensified as a consequence of the Coriolis force driving currents west against continental margins or as current squeezes between two ridges.
