Radioisotope dating assumptions
But what if the original melt already had some radiogenic lead?
The resulting rock would inherit a deceivingly "old" date.
Assumption Two: No parent or daughter material has been added to or taken from the specimen.
We know of many ways in which the materials can be made mobile, most particularly through ground water leaching.
The old-earth model doesn't work, and a better model must replace it.
However, as we look forward to a better alternative, it would behoove us to look back and restate the powerful tried and true arguments relating to the erroneous assumptions and contradictory results.
Furthermore, since the dynamic Flood of Noah's day covered the entire globe, what rock could have escaped its effects?
Assumption Three: No daughter material was present at the start.
Only rocks and minerals which formerly were in a hot molten condition (like lava) can be dated.
This age is computed under the assumption that the parent substance (say, uranium) gradually decays to the daughter substance (say, lead), so the higher the ratio of lead to uranium, the older the rock must be.
Of course, there are many problems with such dating methods, such as parent or daughter substances entering or leaving the rock, as well as daughter product being present at the beginning.Radiometric dating is largely done on rock that has formed from solidified lava.