This has been discussed on FR as little as a few months ago. (The subject comes and goes constantly, the FR for and against is pretty spirited, do a simple search)The more in it than on it line comes from one of those articles posted.
Geology is a Science, as such it evolves with time as more is learned.
In the matter of the Biblical flood one must first understand what is actually said in the Bible and then try to piece together a possible scenario. In ancient times this wasn’t a problem: God. Magic. There. Done. But as mankind uncovered and uncovers more of “God’s august secrets” the logical understanding is that any God who was real would not NEED to use magic as He would be in control of the forces that act upon or within His own creation.
There are two sources of water according to the Biblical account “The fountains of the great deep” a term which is used only once in the Bible and “The windows of Heaven” Lets call the ‘windows of heaven’ “rain” or all atmospheric water. Atmospheric water doesn’t even REMOTELY involve enough water to flood the earth for at least two reasons: 1.) Getting it to rain on ALL of the earth (as the Bible describes)and 2.)The rate of flow from the skies, even if you scaled down the final height of the water to well below the Biblical account, would be something like 6 inches per minute for forty days (Where was the evaporating power of the sun during all of this?).
The Bible however describes the “Fountain” source as being in operation BEFORE the rain(some 7 days?) Geologically there are two sources of water to accommodate a destroying flood: Water in the earth and water on the earth (oceans). Necessarily plate movement,opening of seams etc would come into play at this point since no global flood is possible with out it. At this point the ocean floor shifting (creating massive destroying wave action) and doming prepatory to releasing sub floor water would go a long way toward flooding the land
As a possibility, what exactly is the problem with there being more water in the earth than on it. If you say that that is, on the face of it, ridiculous then you exhibit ignorance of the sheer scale of the earth.
For instance: Look at how much fresh water humans have daily access to and then look at how much of the fresh water that is upon the earth in total is locked up in ice; respectively about 3% and 97% (or something near that).
Now, getting to the “interior” of the earth, the part of the earth that is described in that word is, in thickness with respect to scale of the planet, not even a piece of looseleaf paper. NOT EVEN A PIECE OF LOOSE LEAF PAPER! The most impressive efforts of our miners doesn’t do much more than SCRATCH that thickness of loose leaf yet WATER is in fact one of their most pressing and expensive problems. In fact some of the most impressive monuments to capitalism and human grit and ingenuity remain the MASSIVE pumps created during the Gold Rush of the last half of the 19th century to deal with the flood of first cold then hot water as they descended. Add to that the fact that in a volcanic eruption as much as 75% of the the outflow has been measured to be steam then even in this portion of the earth’s solid layer that is well above the ‘fountains of the great deep’ there is no shortage of water.
Geologically the ‘fountains’ would have to be below the oceans and in terms of simple physics would use the oceans as portals since water is a lot lighter than solid earth. If such water is present it would require a release mechanism as well as a path to subsiding, neither of which is geologically off the scale or even difficult. Indeed in one such place(sub oceanic point between plates) the mantel is not there. It either never formed or was blown away by something. In terms of where 'fountains' would be and how they would release there ain't a hell of a lot of candidates . That narrows down the search considerably.
Any idea why the Gilgamesh epic in Babylonian mythology predates the Noah tale?
1) Have you calculated how many millions of cubic miles of water you are talking about? All of which leaped to the earths surface, then obligingly disappeared by some unknown mechanism?
2) Do you understand capillary action, and how hard it is to squeeze water out of sedimentary rocks?
2) This volume of water flooded the land, yet the vast majority of the Earth's surface shows no trace of this flooding?
3) This volume of water somehow caused so little chemical disruption that the saltwater and freshwater fish were not killed in the process.
(Why do I even bother...?)