U pb dating half life
How radiometric dating works in general Why methods in general are inaccurate Why K-Ar dating is inaccurate The branching ratio problem How Errors Can Account for the Observed Dates Why older dates would be found lower in the geologic column especially for K-Ar dating Do different methods agree with each other on the geologic column?
Even the creationist accounts that I have read do not adequately treat these issues.If these dates are correct, this calls the Biblical account of a recent creation of life into question.After study and discussion of this question, I now believe that the claimed accuracy of radiometric dating methods is a result of a great misunderstanding of the data, and that the various methods hardly ever agree with each other, and often do not agree with the assumed ages of the rocks in which they are found.Since Cambrian and later rocks are largely sedimentary and igneous (volcanic) rocks are found in Cambrian and later strata, if these rocks are really 550 million years old, then life must also be at least 550 million years old.Therefore, my main concern is with rocks of the Cambrian periods and later.In two half-lives, half of the remainder will decay, meaning 3/4 in all will have decayed.
In general, in n half-lives, only 1/(2^n) of the original parent material will be left.
Lead is the element with the heaviest stable isotope, Pb is entirely primordial, and is thus useful for estimating the fraction of the other lead isotopes in a given sample that are also primordial, since the relative fractions of the various primordial lead isotopes is constant everywhere.
As a consequence of this particularly stable configuration, its neutron capture cross section is very low(even lower than that of deuterium in the thermal spectrum), making it of interest for lead-cooled fast reactors.
Perhaps the earth was made from older pre-existing matter, or perhaps decay rates were briefly faster for some reason. Geologic time is divided up into periods, beginning with the Precambrian, followed by the Cambrian and a number of others, leading up to the present.
When one considers the power of God, one sees that any such conclusions are to some extent tentative. Some fossils are found in Precambrian rocks, but most of them are found in Cambrian and later periods.
Lead-204 is entirely a primordial nuclide and is not a radiogenic nuclide.