<Tr> <Td_colspan="2"> Relative to the African Plate </Td> </Tr> <P> The South American Plate is a tectonic plate which includes the continent of South America and also a sizeable region of the Atlantic Ocean seabed extending eastward to the African Plate creating the Mid-Atlantic Ridge </P> <P> The easterly side is a divergent boundary with the African Plate forming the southern part of the Mid-Atlantic Ridge . The southerly side is a complex boundary with the Antarctic Plate and the Scotia Plate . The westerly side is a convergent boundary with the subducting Nazca Plate . The northerly side is a boundary with the Caribbean Plate and the oceanic crust of the North American Plate . At the Chile Triple Junction in Taitato - Tres Montes Peninsula, an oceanic ridge--the Chile Rise--is subducting under the South American plate . </P> <P> The South American Plate is in motion . "Parts of the plate boundaries consisting of alternations of relatively short transform fault and spreading ridge segments are represented by a boundary following the general trend ." Moving westward away from the Mid-Atlantic Ridge . The eastward - moving and more dense Nazca Plate is subducting under the western edge of the South American Plate along the Pacific coast of the continent at a rate of 77 mm (3.0 in) per year . This collision of plates is responsible for lifting the massive Andes Mountains and causing the volcanoes which are strewn throughout them . </P>

The west coast of south america is what plate boundary