| Off the Brazilian coast, the Rio Grande Rise, whose minimum depth is 600 m, acts as a barrier for deep circulation. It is crossed by a long (600 km), deep (4 600 m) and narrow (20 km wide in its central part) channel: the Vema Channel, a junction channel joining the Argentinian and Brazilian basins. Two important currents flow into the Vema Channel. The deepest, the deep Antarctic current, flows from the South to the North at a speed reaching 40 cm/s near the bottom (Le Pichon et al., 1971). Its upper limit is located at around 3 500 and 4 200 m (Le Pichon et al., 1971). Directly underneath, but flowing from the North to the South, is the deep North Atlantic current. Its estimated speed at 2 800 m deep is 15 cm/s. Its upper limit is located at around 1 000... |
