Mountains play an important geological role in stabilizing the Earth's crust. The Qur'an attested to this fact, although it was not known by anyone at the time it was revealed. It was discovered only recently, through modern geological research. Mountains have deep "roots" that extend downwards, sometimes as far as 10-15 times their own height.

They emerge from the movements and collisions of the Earth's crust plates, and act similarly to nails or pegs holding a tent down. The density of the crust beneath mountains is different than beneath plains, which helps to balance the force of gravity and the force of the mantle. This balancing is known as isostasy. The role of mountains in maintaining the stability of the Earth's crust is essential to life on Earth. Mountains act like nails, holding the plates of the Earth's rocky surface together and preventing them from shifting.

This fixing effect of mountains is revealed in the Qur'an and is further confirmed by modern geological and seismic research, which reveals the necessity of mountains in maintaining the density of the Earth's crust.

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