Define relative age dating
However, from a biblical perspective the earth was created by God on Day 1 of the Creation Week before the sun and the rest of the solar system were created on Day 4, all only about 6000 or so years ago.
Yet the earth would still have had an initial (created) Pb isotopic endowment.
There is also primordial Pb that the earth acquired when it formed, its isotopic composition determined as that of troilite in the Canyon Diablo iron meteorite.
Then catastrophic plate tectonics during the Flood stirred the mantle and via partial melting added new rocks to the crust.
One crucial area the RATE project did not touch on was the issue of how reliable are the determinations of the radioisotope decay rates, which are so crucial for calibrating these dating “clocks.” However, in a recent series of papers, Snelling (2014a, b, 2015a, b, 2016, 2017) reviewed how the half-lives of the parent radioisotopes used in long-age geological dating have been determined and collated all the determinations of them reported in the literature to discuss the accuracy of their currently accepted values.
He documented the methodology behind and history of determining the decay constants and half-lives of the parent radioisotopes U which are used as the basis for the Rb-Sr, Lu-Hf, Re-Os, Sm-Nd, K-Ar, Ar-Ar, U-Pb, and Pb-Pb long-age dating methods respectively.
These new rocks rapidly accumulated more Pb isotopes due to the concurrent accelerated radioactive decay of U and Th in them during the Flood.
Thus, without being able to unequivocally distinguish the daughter Pb atoms produced by in situ U and Th decay from the initial Pb atoms in a mineral or rock, it is impossible to determine their absolute U-Pb ages.
The decay of Pb, respectively, forms the basis for one of the oldest methods of geochronology (Dickin 2005; Faure and Mensing 2005).