How can a earthquake with a moderate magnitude have a high intensity

Earthquake magnitude is a measure of the total energy released by the movement (the energy released at the source of the event). This is not directly related to wave intensity at a location away from the origin. It is related, but only partially so. Having low intensity shaking from a moderate earthquake can happen as can high intensity shaking elsewhere, from the same earthquake and even at locations not separated by great distances. 
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