Question

What are faults

Answer 1

If so, a fault is a crack in the Earth's crust. Typically, faults are associated with, or form, the boundaries between Earth's tectonic plates. In an active fault, the pieces of the Earth's crust along a fault move over time. The moving rocks can cause earthquakes.

Answer 2

as in fault lines?

Answer 3

Rock formation that results from the action of plate tectonics.