"..the two seas that meet but do not transgress.."

This blog post contains a short recording of the North Sea and the Baltic sea at their meeting point. It is clear that they do not transgress as they crash into each other forming big waves, just as mentioned in the Holy Quran, 55:19-20;

Normally we see recordings of different colours but here we really can see the two different forces of the two different seas that meet the barrier that is between them, just as mentioned in the Holy Quran.