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How do thrust faults contribute to mountain building?

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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.

Thrust faults are a primary mechanism for mountain building, as they facilitate the horizontal shortening and vertical thickening of the Earth's crust. When tectonic plates collide, horizontal compressional forces cause the crust to fracture and shorten.123

Thrust faults—specifically those with a low angle of dip—allow one block of crust (the hanging wall) to be pushed up and over another (the footwall). This process contributes to mountain building in several ways:3

Crustal Thickening: By stacking slices of crust on top of one another, thrusting increases the vertical thickness of the crust, which results in surface uplift.42
Uplift of Deep Rocks: Large-scale movements, such as those along ramp overthrusts, can displace crystalline rocks from deep within the crust, pushing them onto the surface to create high-elevation ranges.4
Folding: As these slices are thrust forward, they often compress and deform sedimentary layers into anticlines and synclines, forming fold and thrust belts that characterize many mountain chains.42

These processes are fundamental to the formation of major mountain belts, such as the Himalayas and the Alps.43