Geochronologists do not claim that radiometric dating is foolproof (no scientific method is), but it does work reliably for most samples.
It is these highly consistent and reliable samples, rather than the tricky ones, that have to be falsified for "young Earth" theories to have any scientific plausibility, not to mention the need to falsify huge amounts of evidence from other techniques.
This document is partly based on a prior posting composed in reply to Ted Holden.
As an example of how they are used, radiometric dates from geologically simple, fossiliferous Cretaceous rocks in western North America are compared to the geological time scale.
To get to that point, there is also a historical discussion and description of non-radiometric dating methods.
The results from Heaman's team show that the sauropod in question was alive 64.8 million years ago, 700,000 years after the mass extinction, bringing into question the fate of the dinosaurs after the KT extinction.
There could be several reasons why the New Mexico dinosaur and its ancestors survived the KT extinction.
It is widely assumed that the extinction was caused by debris from a giant meteorite which struck Earth, blocking out the sun, causing extreme climate conditions and killing vegetation around the world.