Genesis 7:11 [ESV] In the six hundredth year of Noah’s life, in the second month, on the seventeenth day of the month, on that day all the fountains of the great deep burst forth, and the windows of the heavens were opened.
Noah's flood is typically thought of as being caused by torrential rainfall. That is only partially true. Probably the largest portion of the waters of the flood came from under the earth in great artesian springs that burst forth in amazing power and volume at God's command.
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