Qur'an 24:40 "Or like utter darkness in the deep sea: there covers it a wave above which is another wave, above which is a cloud, (layers of) utter darkness one above another; when he holds out his hand, he is almost unable to see it; and to whomsoever Allah does not give light, he has no light.
Internal wave | Oceanic, Oceanography & Dynamics
Internal wave, a type of gravity wave that occurs on internal “surfaces” within ocean waters. These surfaces represent strata of rapidly changing water density with increasing depth, and the associated waves are called internal waves. Internal waves manifest themselves by a regular rising and
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