Quranic Miracle; the function of mountains

The Qur'an draws attention to a very important geological function of mountains:

We placed firmly embedded mountains on the earth, so it would not move under them… (Qur'an, 21:31)

The verse states that mountains perform the function of preventing shocks in the Earth. This fact was not known by anyone at the time the Qur'an was revealed. It was, in fact, brought to light only recently, as a result of the findings of modern geological research. 

Formerly, it was thought that mountains were merely protrusions rising above the surface of the Earth. However, scientists realised that this was not actually the case, and that those parts known as the mountain root extended down as far as 10-15 times their own height. With these features, mountains play a similar role to a nail or peg firmly holding down a tent. For example, Mount Everest, the summit of which stands approximately 9 km above the surface of the Earth, has a root deeper than 125 km.

Mountains emerge as a result of the movements and collisions of massive plates forming the Earth's crust. When two plates collide, the stronger one slides under the other, the one on the top bends and forms heights and mountains. The layer beneath proceeds under the ground and makes a deep extension downward. Consequently, as stated earlier, mountains have a portion stretching downwards, as large as their visible parts on the Earth.

Furthermore, a book titled Earth, by Dr. Frank Press, former president of the U.S. National Academy of Sciences, which is still used as a text book in a great many universities, states that mountains are like stakes, and are buried deep under the surface of the Earth.27

In other verses, this role of the mountains is pointed out by a comparison with "pegs":

Have We not made the earth as a bed and the mountains its pegs? (Qur'an, 78:6-7)

In another verse it is revealed that Allah (swt) "made the mountains firm." (Qur'an, 79:32) The word "arsaha" in this verse means "was made rooted, was fixed, was nailed to the earth." Similarly, mountains extend to the surface layer joining lines on and below the surface, and nail these together. By fixing the Earth's crust they prevent any sliding over the magma layer or amongst the layers themselves. In short, mountains can be compared to nails holding strips of wood together. 

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