Post by Afirstname.lastname@example.org Post by TheRealMccoy
I do not know how old the earth is
but this is predicated on that the ratio starting of lead and uranium isotopes is identical to that of meteorites
It's fuddy duddy reasoning to say that you can give the dates of the earth in the millions based on the decay rate of uranium.
.> "The dating method is usually performed on the mineral zircon. The mineral incorporates uranium and thorium atoms into its crystal structure, but strongly rejects lead. Therefore, one can ASSUME that the entire lead content of the zircon is radiogenic, i.e. it is produced solely by a process of radioactive decay after the formation of the mineral. Thus the current ratio of lead to uranium in the mineral can be used to determine its age."
Post by Aemail@example.com
"The method relies on two separate decay chains, the uranium series from 238U to 206Pb, with a half-life of 4.47 billion years and the actinium series from 235U to 207Pb, with a half-life of 710 million years."
So, we assume that the lead was in the rock from the get-go - never mind the formation of the zircon from the get-go, that perhaps the lead just happened to be in it, we are so bold to say that we know that nothing has changed over millions or billions of years. In other words the dating system cannot be tested over a vast period of time.
That's pseudo science. you can't prove the earth is millions or billions of years old.
The assumption is based on known mineralogy; it's not just something
someone arbitrarily decided after six beers. If you're going to attack
the argument, you're going to have to show that the crystallography is incorrect.
But beyond that, there are a whole host of techniques that show the age of
the Earth to be a million years or more.
To name just a few: cosmogenic nuclide buildup, iron-
manganese nodule growth, Milankovitch cycles, amino acid
racemization, Naica megacrystals, sedimentary varves, the
Great Barrier Reef, seabed plankton layering, nitrogen
impurities in diamonds.
Note that none of them depend on rates of radioactive decay.
Each of them is independant of all the others. All give
dates over one million years.
I've got some more if you'd like.