What the Bible tells, is the hypothesis, and in short it is:
1. There was single continent at the beginning that was on top of vast water storage that was called the depth.
2. When the flood came, it happened because the original continent was broken and sunk.
3. The broken parts formed the current continents. In their edges, land was compressed and moved so that for example orogenic mountains were formed.
4. Because the water before the collapse was under the earth in compression and in warm conditions, lot of it was vaporized when the water was released. That vapor caused the long rain.
5. Because of the rain and because of death, earth got colder. That resulted to ice age and vast amounts of water was collected to glaciers.
6. When the water was collected to ice, the level of water begun to decrease. Other reason for decreasing was that the sunken earth has been compressed more, causing the water to follow so that dry land has appeared in other places.
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