Radiometric dating instruments 20 year old girl dating 42 yr old man
These elements have much longer half-lives than Carbon, and in some cases can be cross-referenced if more than one of these elements is present in a volcanic tuft.
There are other methods for dating fossils, such as thermoluminescence.
The Christian Creationists have criticized it on the grounds that it is inaccurate.
If a fossil is completely replaced (permineralized), then it would be useless in a similar test - because it no longer is organic.For example, Uranium (U-235 or U-238) runs into the Thorium series then breakdowns into Radium and Radon, and finally, into Lead (the stable isotope).Volcanic tuft containing U-235 also contains (stable) Lead associated directly with it.By comparing the proportion of the two, one can work out how old the deposit is.If the sample is 75% U-235 and 15% Lead (and 10% other), then the sample is approximately 300 mya.