North American Plate | |
---|---|
Type | Major |
Approx. Area | 75,900,000 km2 (29,300,000 sq mi) |
Movement1 | west |
Speed1 | 15–25 mm (0.59–0.98 in)/year |
Features | North America, Greenland, Bering Sea, Atlantic Ocean, Arctic Ocean |
1Relative to the African Plate |
The North American Plate is a tectonic plate covering most of North America, Greenland, Cuba, the Bahamas, extreme northeastern Russia, and parts of Iceland and the Azores. It extends eastward to the Mid-Atlantic Ridge and westward to the Chersky Range in eastern Siberia. The plate includes both continental and oceanic crust. The interior of the main continental landmass includes an extensive granitic core called a craton. Along most of the edges of this craton are fragments of crustal material called terranes, accreted to the craton by tectonic actions over the long span of geologic time. It is thought that much of North America west of the Rocky Mountains is composed of such terranes.
The southerly boundary with the Cocos Plate to the west and the Caribbean Plate to the east is a transform fault, represented by the Cayman Trench under the Caribbean Sea and the Motagua Fault through Guatemala. The parallel Septentrional and Enriquillo-Plantain Garden faults, which run through the island of Hispaniola and bound the Gonâve Microplate, are also a part of the boundary. The rest of the southerly margin which extends east to the Mid Atlantic Ridge and marks the boundary between the North American Plate and the South American Plate is vague but located near the Fifteen-Twenty Fracture Zone around 16°N.