section_path: Modern plates
section_name: Modern plates
paragraph_text: Modern plates
  
  Depending on how they are defined, there are usually seven or eight "major" plates: African, Antarctic, Eurasian, North American, South American, Pacific, and Indo-Australian. The latter is sometimes subdivided into the Indian and Australian plates.
  
  There are dozens of smaller plates, the eight largest of which are the Arabian, Caribbean, Juan de Fuca, Cocos, Nazca, Philippine Sea, Scotia and Somali.
  
  During the 2020s, new proposals have come forward that divide the Earth's crust into many smaller plates, called terranes, which reflects the fact that Plate reconstructions show that the larger plates have been internally deformed and oceanic and continental plates have been fragmented over time. This has resulted in the definition of roughly 1200 terranes inside the oceanic plates, continental blocks and the mobile zones (mountainous belts) that separate them.
  
  The motion of the tectonic plates is determined by remote sensing satellite data sets, calibrated with ground station measurements.