Age of the Solar System

Wallis

Nah, It's OK.

We all get confused. The original question was....

If everything earliest on earth is 4.5 bn years old, surely this is the age of the supernova that made the elements the earth is composed of (certainly younger than 13bn since the solar system is supposedly composed of 3rd generation matter.)

So, why are there no traces of the supernova, just its atoms it made?

The answer, which I quite now accept, is that everythig is reset to 4.5bn which I am now led to believe is the because the big meltdown in the formation of the early earth from planeticimals separated isotopes and made for a big reset in the atomic fingerprint of the elements within the chemicals we now find. That I can now understand given full information on radiometric dating and the assumptions involved. A radiometric date result in itself is ambiguous, but the wholesale support of the 4.5bn year reset is now convincing to me.

Please can we lock this thread? It is exhausting now...

D H

You appear to be assuming that the rocks were well-mixed back when they formed. That is leading you to some misconceptions.

I'll pick zircons as an example. You appear to be assuming that the clock was reset when the atoms that make up the zircon were formed. That is not the case. Scientists use zircons for dating because it is the formation of the zircon that resets the clock. Zircons readily incorporate uranium into their crystalline matrix but strongly reject lead. Uranium is chemically similar to zirconium; lead is chemically very distinct. The chemical processes (not subatomic physics!) that create zircons will selectively pluck the uranium out of a mix of uranium and lead that happens to be nearby the zirconium and silicon dioxide that form the main body of the forming zircon.