According to the Theory of Plate Tectonics, the Earth has seven major or primary plates: the North American, South American, African, Antarctic, Indo-Australian, Eurasian and Pacific. There are also several secondary plates including the Arabian, Caribbean, Indian and Philippine Sea plates, and tertiary plates which make up sub-sections of the major plates of the Earth.
The Theory of Plate Tectonics or Plate Tectonic Theory is a key body of knowledge for geologists trying to figure out "how the Earth works." It basically explains how and why formations such as volcanoes and mountains came about, as well as why earthquakes and tidal waves happen. The movement of the Earth's major plates throughout the planet's history is also responsible for the formation of the seven continents.
Although the seven major plates of the Earth comprise most of the continental surface and the Pacific Ocean, the secondary plates cover the rest of the Earth's surface. There are eight total secondary plates. They are:
- Arabian Plate
- Indian Plate
- Caribbean Plate
- Cocos Plate
- Juan de Fuca Plate
- Nazca Plate
- Philippine Sea Plate
- Scotia Plate
In addition, tertiary plates constitute micro plates within the larger primary and secondary plates. There are 65 of these tertiary plates.