The deep and the great deep are both translated from the same Hebrew word, tehom. The difference signifies a transition from the deep where Earth was created to when the great deep is in the interior of the Earth.
The Great Deep
Absolute Frame of Reference
The idea that the presence of God dwells in a specific place, as a theme, doesn't get picked up until King David wanted to build a temple. Up until that time the Lord used a tabernacle as the center of worship.
The Broad Narrative of Scripture
The Bible is consistent throughout because it combines spiritual concepts, like good and evil, with their physical expression in space and time as light and darkness. It describes their permanent physical separation.
Highest part: וְ֝רֹ֗אשׁ – rosh
IF Eden was at the top of a mountain that filled the whole Earth, and a river from Eden watered the surface of the whole land, THEN the concept of elevation will be found in the scriptural context.
A Mountain Filled the Whole Earth
By adding Daniel to Isaiah and Zechariah we, that's me and the Holy spirit, are starting to build a deep bench of prophets who foresaw the changes which take place at the beginning of the Millennial Kingdom.
November 1st
In November we consider unfulfilled prophecy in the context of the spherical hollow Earth model that we deduced in March. How does 3D modeling affect our understanding of the plagues of the tribulation?