Additionally, what evidence do you use to justify imposing the data of a decay rate able to be observed over, at best, a millennium or two to a time span of 10 million years.
The "evidence" of quantum mechanics. That's why I brought it up. Half-lives, like spectral lines, are an inherent property of their nuclei. The rate of decay does not change any more over a period of a billion years than it does over a period of a million or a thousand years, or a single year.
either way, ask yourself a quick question...given the amount of nuclear explosions that have occurred on the earth, what impact will they have on the reliability of radiometric dating in the distant future?
Since radiocarbon dating is ineffective over timespans longer than a few thousands of years, and radiometric dating for geologic processes does not use Carbon-14 but much longer-lived isotopes, current nuclear tests won't affect future measurements at all (assuming "distant future" means >10,000 years from now).
let me footnote that i have no particular disagreement with plate tectonics
Happy to hear it!
however, it is clear to the most cursory of scientific understanding that continental drift has little to confirm/deny with regards to a "flood"
That's true on the surface, but obviously false if the "flood" in question is asserted to have occurred on a single continental landmass that still existed as a single continental landmass as of ca. 2300 BCE. In that case, existing radiometric and geologic evidence utterly discounts the possibility of such a flood.
As a side note, there is good anthropological and geological evidence that the Mesopotamian region experienced periodic catastrophic flooding, including particularly devastating regional floods sometime around 3000 BCE.
