theory of the polate tectonics~~ 6 key points

1. > earth's crust is divided into plate tectonics, the largest piece is called the pacific plate.
2. > the 2 crusts that earth's crust is broken up into is called oceanic crust and continental crust.
3. > we live on the continental crust.
4. > the study of how plates move is called plate kinematics.
5. > subduction is one plate being forced under anothe plate.
6. > slow spreading ridges make rift valleys while fast spreading ridges usually don't have rift valleys.