Radiometric dating on sedimentary rocks avid dating life
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.
Potassium 40 (K40) decays to argon 40, which is an inert gas, and to calcium.
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.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.For potassium 40, the half-life is about 1.3 billion years.In general, in one half-life, half of the parent will have decayed.
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We can assume that the Precambrian rocks already existed when life began, and so the ages of the Precambrian rocks are not necessarily related to the question of how long life has existed on earth.