Ocenology...

BARRIER BETWEEN SWEET AND SALT WATERS
Modern Science has discovered that in the places where two different seas meet, there is a barrier between them. This barrier divides the two seas so that each sea has its own temperature, salinity and density. This phenomenon occurs in several places, including the divider between the Mediterranean and the Atlantic Ocean at Gibraltar. Consider the following Qur’anic verses:

"He has let free the two bodies of flowing water, meeting together: Between them is a Barrier which they do not transgress." [Al-Qur’an 55:19-20]

In the Arabic text the word ‘barzakh’ means a barrier or a partition as used in the Holy Qur’an. This scientific phenomenon mentioned in the Qur’an was also confirmed by Dr. William Hay who is a well known marine scientist and Professor of Geological Sciences at the University of Colorado, U.S.A.

But in ‘Estuaries’ where fresh (sweet) and salt-water meet, the situation is somewhat different. It has been discovered that what distinguishes fresh water from salt water in estuaries is a ‘pycnocline’ zone with a marked density discontinuity, separating the two layers. This zone has a salinity different from both the fresh & salt water. This phenomenon occurs in several places including Egypt, where Nile flows in to the Mediterranean Sea. The Qur’an mentions this phenomenon also in the following verse:

"It is He Who has let the two bodies of flowing waters: One palatable and sweet, and the other salty and bitter; yet He has made a barrier between them, and a partition that is forbidden to be passed" [Al-Qur’an 25:53]

DARKNESS IN THE DEPTH OF THE OCEAN
Humans are unable to dive unaided underwater for more than 20 to 30 metres. As one goes deeper and deeper, the darkness increases layer by layer, due to successive disappearance of visible colors starting from red to violet depending on the wavelength of the band & depth travelled under water.

The darkness under water increases manifolds on a cloudy day when the Sun’s rays are absorbed and only scattered light reaches the surface of the ocean. The Qur’an mentions this phenomenon also in the following verse:

"Or it is like the depths of darkness in a vast deep ocean, overwhelmed with a great wave (billow) topped by a great wave (billow), topped by dark clouds, darkness one after another, if a man stretches out his hand he can hardly see it. And he for whom Allah has not appointed light, for him there is no light." [Al-Qur’an 24:40]