Figure 2. SeaBeam box survey. The shift in the bathymetry on the southern edge of the valley is real, and not an artifact. The tracer was released over this valley at 21.7 S, 18.4 W. The current meter mooring was in the valley to the east of this point at 21.6 S, 17.8 W. The abyssal hills, elongated in the meridional direction and steep in the zonal direction are believed to be responsible for the generation of internal waves, which in turn lead to mixing.