After a couple of months of this work, they would be further south than where they started. This would leave evidence of itself in the form of marine sediments covering Turkey, yet except along river valleys, Turkey is covered by sediments which are Miocene and older. Miocene and older sediments are prior to the advent of man on earth. Lack of sediment from a widespread Mesopotamian Flood. A syllogism can be constructed.
All floods leave sediments covering what they flooded.
Noah's Deluge was a flood. Therefore Noah's deluge must have left sediment. All uneroded flood sediments can be detected by geology. To completely erode flood sediments takes more than 20,000 years. There are no widespread sediments dating from less than 20,000 years ago.