The type of stress that causes fault-block mountains is tension.
- Fault-block mountains form where the Earth’s crust is being pulled apart, which is tensional (extensional) stress.
- This pulling apart creates normal faults, and blocks of crust drop down or tilt, producing alternating mountains and valleys.
- Compression, shearing, and subduction are involved in other tectonic settings, but the correct choice from your list is tension.