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Figure 2. A present-day Nigeria slope channel and its geomorphological parameters. The channel thalweg depth is in red, thalweg depth in blue and the channel gradient in light green. The presumed slope depositional equilibrium profile is shown in dotted pink. The channel extends across three seafloor topographic highs (i.e., High 1, High 2 and High 3) associated with either shale-cored diapirs or thrust-generated anticlinal structures. Note the thalweg elevation for the channel segment directly across these highs is above the equilibrium profile, suggesting potential for further down cutting and headward erosion. The deepest part of the channel thalweg, as shown by the channel thalweg depth curve (blue), occurs at approximately the intersection point between the thalweg elevation and the equilibrium profile curves. Channel depth gradually decreases downdip from the intersection point as a result of deposition within the channel thalweg. Sand deposition across the channel should be expected to occur primarily on the downslope sides of the highs because of (1) a relatively greater accommodation spaces, and (2) hydraulic jumps within turbidity current flows emanating from the highs. (Modified from Pirmez, et al., 2000.)