To me it has been a real eye opener to see all the processes that are taking place and their potential influence on radiometric dating.Radiometric dating is largely done on rock that has formed from solidified lava.

These long time periods are computed by measuring the ratio of daughter to parent substance in a rock and inferring an age based on this ratio.

This age is computed under the assumption that the parent substance (say, uranium) gradually decays to the daughter substance (say, lead), so the higher the ratio of lead to uranium, the older the rock must be.

Leaching of the parent element out of the rock would increase the age of a K-Ar sample.

One way to test this would be to analyze the sample before and after soaking it under pouring water.

Therefore, since sedimentary rock is the only kind of rock that bears fossils, a relative date is estimated by the position of a sedimentary rock in relation to an igneous outflow.

There is a discussion of a few examples of radiometric methods with sedimentary rocks in Creationists believe that the assumptions of radiometric dating are invalid and cannot be proven.Lava erupting earlier would come from the top of the magma chamber, and lava erupting later would come from lower down.A number of processes could cause the parent substance to be depleted at the top of the magma chamber, or the daughter product to be enriched, both of which would cause the lava erupting earlier to appear very old according to radiometric dating, and lava erupting later to appear younger.We believe that since evolutionists expect certain rocks to yield dates that agree with their theory, no laboratory will publish dates that are wildly out of whack, or they wouldn’t get paid for producing a result that would be hotly contested as experimental error.Woodmorappe shows that even the published results are enough to render the method as unreliable. John Woodmorappe’s books are advertised elsewhere on my web site.