Fault-block mountains are formed through tectonic processes, specifically by the movement of the Earth's crust along faults. These mountains arise when large blocks of the Earth's crust are lifted or tilted due to tectonic forces, creating steep, rugged landscapes. The movement can result in a series of parallel ridges and valleys. Examples of fault-block mountains include the Sierra Nevada in California and the Wasatch Range in Utah. These mountains often feature sharp peaks and steep slopes, making them distinct from other mountain types. The geological activity that creates them can also lead to earthquakes in the surrounding areas.