In Atlantic and Mediterania
In Al-Qur’an Surah Ar-Rahman/ 55(The Beneficent): ayah 19-20
19: “He hath loosed the two seas. They meet. “
20: “There is a barrier between them. They encroach not (one upon the other).”
And Al-Furqan/ 25 (The Criterion, of Right and Wrong): ayah 53
53: “An He it is Who hath given indevendence to the two seas  (though they meet); one palatable, sweet, and the other saltish, bitter; and hath set a bar and a forbidding ban between them”.
. i.e. the salt water and the sweet
. i.e. the two kinds of water in earth