Geosat alti � eter d � ta taken during a I-year period over the oceans around South Africa have been proc � ssed .. Th � s area IS well known for its many interesting current systems and bathymetric features T�e .m .v es!lgatlon h � s focused on the elimination of the radial orbit errors by means of the crossove; minimizatIOn techmque an� o. n .the computation of mean sea surfaces and the determination of meso � cale sea surface .vana�lhty . . For three tracks over this area the collinear tracks analysis tec�nlque has been apphed to mve � tlga � e in detail both the mesoscale ocean surface variability and the honzo � tal component c: f the gravity dl � t � rbance vector . Various interesting geophysical and ocean ographic features are dlsc � sse .d. J!1 addition, the recovered Geosat radial orbit error over this area is analyzed, and the global dlstnbutlOn of the radial orbit errors is estimated .