Dating in reading
Helium is not light enough to escape the Earth's gravity (unlike hydrogen), and it will therefore accumulate over time.
The current level of helium in the atmosphere would accumulate in less than two hundred thousand years, therefore the Earth is young.
Those which appear the most frequently in talk.origins are reproduced below: Note that these aren't necessarily the "best" or most difficult to refute of young-Earth arguments.
However, they are quite popular in modern creation-"science" literature (even though they should not be!
The most direct means for calculating the Earth's age is a Pb/Pb isochron age, derived from samples of the Earth and meteorites.
This involves measurement of three isotopes of lead (Pb-206, Pb-207, and either Pb-208 or Pb-204).
The oldest rocks which have been found so far (on the Earth) date to about 3.8 to 3.9 billion years ago (by several radiometric dating methods).
he generally accepted age for the Earth and the rest of the solar system is about 4.55 billion years (plus or minus about 1%).
This value is derived from several different lines of evidence.
For example, Henry Morris says: He lead to similar results, i.e., a rate virtually identical to the estimated production flux.
Another possible escape mechanism is direct interaction of the solar wind with the upper atmosphere during the short periods of lower magnetic-field intensity while the field is reversing.