Andrew: My argument, if you want to call it that, is: Could the natural
creation of heavier elements leave a trail that could be misinterpreted
isochrone data?>>
Theoretically perhaps, practically it would require mechanisms, observations etc. Furthermore this should happen to all the different isochron methods at the same rate.
> For example, isochron methods are the most reliable radiometric
> dating methods. This is because they have a built-in indication
> that lets you know when the dating assumptions have been
> violated, which would make the date meaningless. The following
> methods were applied to a single sample of the Greenland Amsitoq
> Gneiss: [12]
>
> Rb-Sr isochron 3.70 +- 0.14 billion years
> Pb-Pb isochron 3.80 +- 0.12 billion years
> U-Pb discordia 3.65 +- 0.05 billion years
> Th-Pb discordia 3.65 +- 0.08 billion years
> Lu-Hf isochron 3.55 +- 0.22 billion years
Andrew: Wast the testing blind?
I don't know. The data are easily accessible in their original papers. Do you have any evidence that there are problems with these data ?