Here's why:

* Strike-slip faults are characterized by horizontal movement of the rock masses on either side of the fault. The movement is parallel to the strike of the fault (the direction of the fault line).

* Minimal vertical movement: Strike-slip faults primarily involve horizontal displacement, meaning there's not much upward or downward movement, like you described.

Examples of strike-slip faults:

* The San Andreas Fault in California is a major strike-slip fault, responsible for many earthquakes in the region.

* The North Anatolian Fault in Turkey is another example, known for its significant horizontal displacement.

Let me know if you'd like more information on strike-slip faults or other types of faults!