I don't have much time to write this so if I don't get to every thing I will later. Could you repeat your question about radioactive isotope decay. I would be much obliged.
"We know for a fact that the movement of the continents does not happen quickly, but rather very slowly." Unless a a major event occurs I agree.
"The Mid-Atlantic ridge is only diverging at roughly a few centimeters a year." Yes currently it is.
"That is including major and minor seismic activity. Do you have an answer for that?" You bet. This might get long so hang on. Currently the best theory aobut how the flood occurd is as follows:
About 4400 years ago a comet, yes that would be a gaint ball of ice, came thru the solar system. No weither God "nudged" it or let it be is said, but oh well. This comet entered the earth's atmosphere near the earth's northern pole. As it entered the atmosphere it cause a major shift in the top layer of the Atmosphere, which was basically water vapor, this dramatic shift caused it to rain. Actually it had never rained before or at lest not enough to ever mention it. This was because the earth's axis was at 0 and this allows for basically late spring conditions over nearly the whole earth. There was also double the earth's current air preasure avalible at the time. (With out double air preasure insects of enormuse size could have never existed. This is due to that fact that as one incresses volume one decres the surface area to volume. While not a problem if you have lungs it is a major problem if you breath thru your skin like insects do. So just from insect fossils we know that this atmosphere must have existed at one time.) Any way since a comet's temperature is about -300 deg F. as it ripped thru the atmosphere it would cause a major L front this frount mixed with the H, that was basicaly the entire earths atmosphere, and caused huge storms that we probably can't even imagine. The entire upper atmoshpere, miles of water vapor, may have rained down upon the earth.
While the rain alone may have been enough to kill the earth's whole population of man an land animals, but God is very thougheroh.
I'll have to finish latter bye.