action - something that you do protective - (being) something that protects protective action - things you do, to protect yourself or other people (from something) recomâ¦mendations - someone has done some research; this is a list of what they think is good protective action recommendations - a list of things someone thinks you should do to protect ...
Stable isotope analysis gives an independent measure of fractionation such that if, for instance, a sample is 1.5% heavier in 13C than modern standard carbon through the effects of fractionation, then it will be 3% heavier in 14C than it would have been had fractionation not taken place.
With the exception of Carbon-14, radiometric dating is used to date either igneous or metamorphic rocks that contain radioactive elements such as uranium. And even though various radioactive elements have been used to date these rocks, for the most part, the methods are basically the same. They consist of measuring the amount of radioactive (mother) element and comparing it to the amount of stable (daughter) element. A discussion of the Uranium/Lead method follows. Uranium is radioactive, which means it is in the process of changing from an unstable element into a stable one.