Quick radiometric dating question- misused techniques

Not an expert, and I am talking off the topic of my head.I think that K/Ar dating is suitable for dating the Earth's oldest rocks. At least those that had high enough K content to begin with. Dating low K rocks is a another mater.The catch it, K/Ar is particularly subject to reseting by more recent thermal events - Metamorphism. As such, the date you would get would be the date of metamorphism, not the origin date of the igneous rock. It's possible to date the same rock using different methodology, and to then get different dates. But they may well be different because you are dating different events in the rocks history.Enough from me. Better listen to the real experts around here.Moose

LindaLou, in message 9, was considering datings using such methods as K/Ar, Rb/Sr, and U/Pb. For such long lived isotopes there is or can be a minimum possible datable age.You responded to her and jumped to C14 dating, where there is a maximum possible datable age.You were not responding to the subtheme that LindaLou was discussing.Minnemooseus (w/ Adminnemooseus looking over shoulder)