continental and oceanic plates
Continental crust- This crust forms the continents that we know today, and it's made of granite making it less dense than the oceanic crust. (can't sink, cannot be renewed or destroyed, older, 1500 million years old)
Oceanic Crust- This forms under the oceans and is made of basalt and is very dense (denser, sinks, can be renewed or destroyed, igneous rock, basalt, newer, 200 million years old)