A body of water with a high concentration of suspended sediment which occurs near the deep ocean bottom, close to the base of the continental slope. Nepheloid layers are usually 1–300 m thick, and carry sediment up to 12 μ‎m in size, in concentrations of 0.3–0.01 mg/l. The sediment is suspended and transported by the movement of the oceanic thermohaline bottom currents. See contour current.