Creationists make the claim that a global flood has messed up the precision of radiocarbon dating and hence, it cannot be relied upon. But if it is consistently cross-referenced by other methods, then the claim doesn't quite work.
I wonder if there were specific studies showing that let's say a supposed prehuman species dated at X years old are found surrounded by tools and rocks dated same X years old by argon-argon method or some such.
Examples of the claim:
What role might the Genesis Flood have played in the amount of carbon? The Flood would have buried large amounts of carbon from living organisms (plant and animal) to form today’s fossil fuels (coal, oil, etc.). The amount of fossil fuels indicates there must have been a vastly larger quantity of vegetation in existence prior to the Flood than exists today. This means that the biosphere just prior to the Flood might have had 500 times more carbon in living organisms than today. This would further dilute the amount of 14C and cause the 14C/12C ratio to be much smaller than today.
When the Flood is taken into account along with the decay of the magnetic field, it is reasonable to believe that the assumption of equilibrium is a false assumption.
Because of this false assumption, any age estimates using 14C prior to the Flood will give much older dates than the true age. Pre-Flood material would be dated at perhaps ten times the true age. ...
The average 14C estimated age for all the layers from these three time periods was approximately 50,000 years. However, using a more realistic pre-Flood 14C /12C ratio reduces that age to about 5,000 years. ...
An alternative interpretation of the carbon-14 data is that the earth experienced a global flood catastrophe which laid down most of the rock strata and fossils.
Answers in Genesis
AiG, a very popular Creationist website, has many other articles that say similar things.