Steven Dutch, Professor Emeritus, Natural and Applied Sciences, Universityof Wisconsin - Green Bay
Scale: 1 pixel = 10 km. 10-degree grid; Lambert Azimuthal Equal Area Projection, Center 90S 0EW
Before Pangaea broke up, the Pacific margins of North America, South America and Antarctica were continuous and bordered by a continuous subduction zone. As the three continents rifted away from the rest of Pangaea, they also rifted apart from one another. Spreading centers formed in the gaps and bouyant, hot oceanic crust pushed eastward over the older and colder Atlantic crust. The gaps are now filled by narrow tongue-shaped plates, the Caribbean and Scotia Plates. The Antarctic Peninsula is a former continuation of the southern Andes.
Alao note the eastward protruding tongue of South America, extending beyond the Falkland Islands and connected by a megashear to South Africa. The southern Tip of Africa once fit into the re-entrant north of the Falkland Islands.
Created 11 April 2014, Last Update 19 January 2020