Galápagos Rise

[2] The rise is made up of a series of inactive ridge and transform segments, currently within the northwestern part of the Nazca plate, between about 8° and 17° South latitude.

[2] The northern part of the ridge between 9.4° and 11.2° South is orientated north–south and contains in its most northerly portion a rift that descends to depths of 4,700 m (15,400 ft), which is a feature suggestive of previous slow spreading.

[4] Beyond 10.2° South is a ridge that reaches within 500 m (1,600 ft) of the sea surface and is associated with multiple volcanic cones which must have erupted after spreading had ceased.

Eventually these two ridges isolated a piece of older oceanic lithosphere, forming the Bauer microplate by between 18.5 and 18 Ma (chron 5D and 5E),[4][5] that began to rotate anti-clockwise.

[4] The presence of a shallow rise between the East Pacific Raise and South America was suspected from studies reported in 1956 by Maurice Ewing and Bruce C.