prize9-5, Exercise 2: Faults and plate boundaries

Model answer (check the details):

Normal faults: divergent boundaries (rifts), where tension stretches the crust. The crust becomes wider and thinner, and blocks drop down to form rift valleys.

Reverse and thrust faults: convergent boundaries, where compression squeezes the crust. It becomes narrower and thicker, forming mountain belts.

Strike-slip faults: transform boundaries, where shear moves blocks sideways. The width of the crust is roughly unchanged, although local bends can create small basins or ridges.

Care: all three can also occur away from plate edges, inside plates, and a single zone can combine types.