South American Plate

The South American Plate is a central or primary tectonic plate. Although it is the smallest major plate, it underlies much of the continent of South America and includes a sizable region of the Atlantic Ocean seabed.

The theory of plate tectonics states that the Earth's solid outer crust is separated into plates that move over the molten upper portion of the mantle. Convergence occurs when two plates are pushing into each other. Divergence occurs when plates pull away from each other.

The northern edge of the South American Plate forms a boundary with the Caribbean Plate and the oceanic crust of the North American Plate.

_{Map of South American plate boundaries}

The southern edge of the South American Plate is a complex boundary with the Antarctic Plate, the Scotia Plate, and the Sandwich Plate

The South American Plate extends eastward to the African Plate. As a result, the two plates are pulled apart from each other. Divergence occurs when plates pull away from each other.

This diverging plate boundary forms the southern part of the Mid-Atlantic Ridge, some of the youngest oceanic crust on the planet. The ridge is located on the floor of the Atlantic Ocean and forms the most extended "mountain range" in the world.

The westward-moving South American Plate is moving away from the Mid-Atlantic Ridge, and on its western edge, it forms a convergent boundary with the subducting Nazca Plate. Convergence occurs when two plates are pushing into each other.

The eastward-moving and denser Nazca Plate is subducting under the western edge of the South American Plate along the continent's Pacific coast, resulting in the most extended convergent boundary on Earth.

At the Chile Triple Junction, near the west coast of the Taitao-Tres Montes Peninsula, an oceanic ridge known as the Chile Rise is also actively subducting under the South American Plate.

This subduction zone generates frequent large earthquakes. The collision of these plates is also responsible for lifting the massive Andes Mountains, home to more than 200 potentially active volcanoes, along four Andean Volcanic Belts:

• the Northern Volcanic Zone

• the Central Volcanic Zone

• the Southern Volcanic Zone

• the Austral Volcanic Zone

_{Map depicting the major tectonic plates of the world}