Radiometric dating vs carbon 14
It is assumed that we are dealing with a closed system—no loss of either parent or daughter elements has occurred since the study material formed.
No scientist can guarantee that any sample can be considered a closed system unless it was isolated from its environment when it was formed.
Evolutionists assume that the rate of cosmic bombardment of the atmosphere has always remained constant and that the rate of decay has remained constant.
Levels of carbon-14 become difficult to measure and compare after about 50,000 years (between 8 and 9 half lives; where 1% of the original carbon-14 would remain undecayed).This technique is widely used on recent artifacts, but educators and students alike should note that this technique will not work on older fossils (like those of the dinosaurs alleged to be millions of years old).This technique is not restricted to bones; it can also be used on cloth, wood and plant fibers.Carbon-14 comes from nitrogen and is independent of the carbon-12 reservoir.If even a small percentage of the limestone deposits were still in the form of living marine organisms at the time of the Flood, then the small amount of carbon-14 would have mixed with a much larger carbon-12 reservoir, thus resulting in a drastically reduced ratio.