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How does block faulting form mountains?

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A car drives along the Trans-Canada Highway with Mount Sir Donald's sharp, snow-capped peak rising above forested slopes in the Selkirk Mountains, British Columbia. — mountain Mount Sir Donald in the Selkirk Mountains, British Columbia, looms above a segment of the Trans-Canada Highway.

Block faulting creates mountains when large masses of rock are elevated relative to their surroundings through tectonic activity. This process occurs primarily in two ways:1

Tensional Forces: When the Earth's crust is pulled apart, blocks of rock may subside, leaving behind elevated sections known as a horst. Conversely, the blocks that drop down form basins or rift valleys.123
Compressional Forces: Blocks can also be thrust or pushed over neighboring valleys, a process observed in ranges like the Tien Shan.1

In many cases, these blocks tilt as they move along faults, resulting in landforms characterized by a steep slope on one side and a more gentle slope on the other. While some block-fault mountains exist as isolated ranges, others coalesce to form extensive mountain belts. The Basin and Range Province in the western United States is a prominent example of this tectonic style, where alternating ranges and basins define the landscape.14