If the material is not concordant, the isotopic characteristics of this material may be examined in some detail.
Here, models similar to those used to describe the U-Pb system are evaluated for use in U-Th-Pa studies, for the case in which initial Pa gain or loss are considered for the case in which initial U concentration is significant (for example, in many carbonate deposits).
In some instances, the parent substance may decay directly into the end product.
Sometimes, the radioactive chain may begin with an element partway down the decay chain.
These factors can change or vary with a change in certain conditions.
Rates are really statistical averages, not deterministic constants.
It is based on the formation of radioactive elements of carbon, in the atmosphere by cosmic radiation, and their subsequent decay to the stable carbon isotope.If these assumptions are correct, this dating technique can produce accurate results.Th.)The radioactive element uranium-238 is soluble in water.Several methods for dating ancient materials have been developed.This is an important topic; for evolutionists want the history of earth to span long ages, in the hope that this will make the origin and evolution of life more likely.