Image from Pearson 2012
Pearson text - See Chapter 10.2
page 324
There are two (2) types of crust:
1- Continental crust: is the crusts forming the continents; has a lot more silicon and aluminium
2- Oceanic crust: is found on the ocean floor; is denser than Continental crust because it has less silicon and heavier elements such as iron and magnesium
2- Oceanic crust: is found on the ocean floor; is denser than Continental crust because it has less silicon and heavier elements such as iron and magnesium
See Minute Science video (below) (http://www.sciencealert.com/watch-here-s-how-plate-tectonics-actually-work)