The mountains were very likely nowhere near as high as they are today. In fact, most of the mountains were most likely created after the Flood, as the water was receding. Dr John Baumgardner, Los Alamos Labs, New Mexico, created a program called TERRA with a grant from NASA. With his computer modeling, he demonstrates the plate tectonic processes involved in the formation of terrain as we see it today. It is considered one of the four top computer models in the world today, and demonstrates this entire process of mountain formation and the formation of the continents as we know them today.
CATASTROPHIC PLATE TECTONICS: A GLOBAL FLOOD MODEL OF EARTH HISTORY
More references are available.
How could mountains be created by flood waters receding? Receding from what point? How does that push up land into mountains almost 30,000 feet high?
But regardless, there were mountains of some kind. Be they 5,000 feet high or 10,000 feet high that's still thousands of feet of water that had to come somewhere. Where did it come from and where did it go to?
And what about fresh water and salt water? The Earth's waters are 97% salt. Undrinkable. Catastrophic to farm land. If the flood covered the entire globe to a depth of hundreds or thousands or tens of thousands of feet then that means the tiny proportion of fresh water was basically swallowed up in a sea of saltwater. So without any fresh water again what did Noah drink? Without any land uncontaminated by saline how did anything grow?
So the mountains just grew like mad right up until the time we could accurately measure them, then they slowed down to a normal rate?
Is this what happened to the continents too? Separated at a rapid rate after the flood (so the poor kangaroos wouldn't have to swim all the way home), but slowed down just as we started measuring the actual separation rates?
Do you really believe this stuff?
You know the movement of tectonic plates is responsible for volcanoes and earthquakes? Earthquakes come about from plates moving very short distances, 30 feet max that we've seen (thank goodness). Any type of catastrophe causing sudden orogeny of thousands of feet would result in massive earthquakes and volcanic eruptions. The result would be a global extinction similar in magnitude to the disaster that wiped out almost all life at the end of the Permian--a global flood would look like nothing in comparison. Floating about in a boat wouldn't save you, and things wouldn't be getting better for, oh, about half a million years.