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.
By measuring the amount of radioactive decay of a radioactive isotope with a known half-life, geologists can establish the absolute age of the parent material. A number of radioactive isotopes are used for this purpose, and depending on the rate of decay, are used for dating different geological periods.eochronology is the science of determining the age of rocks, fossils, and sediments using signatures inherent in the rocks themselves. Absolute geochronology can be accomplished through radioactive isotopes, whereas relative geochronology is provided by tools such as palaeomagnetism and stable isotope ratios.