Scotia Tectonic Plate: South Sandwich Tectonic Plate

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Scotia Tectonic Plate: South Sandwich Tectonic Plate

Sat, 12/26/2020 - 14:59

The Scotia Plate and South Sandwich Plate are minor tectonic plates located at the southern edge of the South Atlantic Ocean and the Southern Ocean's northern edge surrounding Antarctica. The South Sandwich Islands are located here.

Scotia Plate

The Scotia Plate is a tectonic plate underlying the Scotia Sea, located at the southern edge of the South Atlantic Ocean and the northern edge of the Southern Ocean (or Antarctic Ocean) surrounding Antarctica.

The plate joins the southernmost Andes to the Antarctic Peninsula much like the Caribbean Plate joins the northernmost Andes to North America.

The Scotia Plate is approximately 800 km (500 mi) wide and 3,000 km (1,900 mi) long, and it is moving WSW at about 2.2 cm (0.87 in) per year. It is a minor plate whose movement is primarily controlled by the two major plates surrounding it.

The Scotia Plate borders the South American Plate to its north, the Antarctic Plate to its south and west, and the South Sandwich Microplate to its east.

At present, the plate is almost entirely submerged, with the only exceptions being the southern tip of South America (at Isla de los Estados just off Tierra del Fuego) and the South Georgia Islands on its northeastern edge: the exposed elements of the oceanic ridge known as the Scotia Arc.

Transform fault boundaries are present with the South American Plate in the north and the Antarctic Plate in the south. There is a spreading boundary in the east with the South Sandwich Microplate. The western boundary with the Antarctic Plate is more complex.

Tectonic setting of the Scotia Plate

Map depicting the tectonic setting of the Scotia Plate and South Sandwich Plate

South Sandwich Plate

The South Sandwich Plate (or Sandwich Plate) is a minor tectonic plate. The South Sandwich Islands are located on this plate. It is bounded by the subducting South American Plate to the east, the Antarctic Plate to the south, and the Scotia Plate to the west.

The South Sandwich Plate is separated from the Scotia Plate by the East Scotia Rise, a back-arc spreading ridge (submarine geologic basin) formed by the subduction zone on its eastern margin.