It is composed of magmatic rocks and is scientifically considered to be the volcanic track of a mantle plume impinging on the South American tectonic plate which has thrown up a series of volcanic cones over the last 140 million years since the start of the Cretaceous period.
The ridge forms a west–east-trending line of submerged mounts and banks that extends from the Brazilian eastern continental shelf around the state of Espirito Santo and stretches out into the deep-water portion of the southern Atlantic Ocean.
The Trindade Archipelago, located 1200 km away from the coastline, forms its eastern terminus.
The ridge only breaks the surface of the South Atlantic to form the Trindade and Martim Vaz archipelago where relatively recent volcanism (Holocene) has thrown up substantial cones.
[1][2][3][4][5][6] The following are major high points along the ridge from west to east, all spread along the 20o South latitude.