Naomi
The earth is made up of the inner core, the outer core, the mantle and the crust. The crust is the thinnest part, it is about 25 miles thick.
When two surface plates rub against each other, energy builds up in the plates.
This energy may build up for years.
The rocks on the plates shift suddenly and free their energy, which makes an earthquake.
Psalm 60:2
Thou hast make the earth tremble; thou hast broken it:
heal the breaches thereof; for it shaketh.
Naomi's Learning 
Well done indeed, Naomi. I have no suggested edits or corrections! You are concise, accurate, and informative. 🙂
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