Bendy rocks?

I’ve been really busy the last couple of weeks, putting together some sessions on how to identify rocks for 1st year engineering students.

One of the most fun parts of it is looking at bendy rocks. ‘Bendy rocks’ I hear you say ‘that can’t be right’! Well, when rocks are heated and pressured deep within the Earth during mountain building, they do indeed bend.

Schist - the minerals have formed bendy layers

The process is called metamorphism and happens when heat and pressure aligns minerals into layers and causes them to re-crystalise. The more heat and pressure, the more this happens, until the rock eventually melts and is reabsorbed back into the mantle beneath the Earth’s crust.

Gneiss - the minerals now form wavey folds and destinct layers

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