(ix) The seas not mingling with one another
“He has set free the two seas meeting together. There is a barrier between them. They do not transgress.” (The Quran, 55:19-20)
Modern science has discovered that at places where two different seas meet, there is a barrier between them. This barrier divides the two seas so that each has its own temperature, salinity and density.
But when the Quran speaks about the divider between the fresh and salt water, it mentions the existence of a “forbidding partition” with the barrier. Allah says in the Quran:
“He is the one who set free the two kinds of water, one sweet and palatable, and the other salty and bitter. And He has made between them a barrier and a forbidding partition.” (25:53)
One may ask, why did the Quran mention the partition when speaking about the divider between sweet and salt water, but did not mention it when speaking about the divider between the two seas??
Modern science has discovered that in estuaries [where fresh (sweet) and salt water meet] the situation is somewhat different from what is found in places where two seas meet. Scientists have discovered that what distinguishes fresh water from salt water in estuaries is a “pycnocline zone with a marked density discontinuity separating the two layers.”[1] This partition (zone of separation) has a different salinity from the fresh water and from the salt water. This information has been discovered only recently, using advanced equipment to measure temperature, salinity, density, oxygen dissolubility, etc. The human eye cannot see the difference between the two seas that meet. Likewise, the human eye cannot see the division of water in estuaries[2] into three kinds: fresh water, salt water, and the partition (zone of separation).
The interesting side to this is that during a period when people had no knowledge of physics or oceanography, this fact was revealed in the Quran.
