The formation of faults in Earth's crust is an effect. What causes faults to form in the crust? Global Positioning System sensors beds shaking across New York City the movement of tectonic plates landslides across the Midwest

The movement of tectonic plates

Explanation:

Tectonic plates are the part of the earth's crust that both the ocean and land rest on. These plates are constantly moving as a result of currents in the mantle.

These movements cause stress on the surface which has the effect of fracturing rocks and thereby creating/ forming faults in the earth's crust. Sometimes faults form when these plates move away from each other and sometimes they are formed when they push into each other.