It's fine but for two little quibbles. Since you are writing on a scientific topic you might want to avoid the word "elements" which has a specific scientific meaning different from the meaning you intend. Instead you could use "substances in" or "constituents of" the earth's crust.
The second minor point is that you could do without the commas. Personally I would eliminate all of them, but failing that at least the first one should be eliminated.
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