Argon argon dating definition
For inorganic materials, such as rocks containing the radioactive isotope rubidium, the amount of the isotope in the object is compared to the amount of the isotope's decay products (in this case strontium).
The object's approximate age can then be figured out using the known rate of decay of the isotope.
and the ages of fossil hominids, molecular dating and divergence times for mammalian lineages, meteorites and the age of the solar system, and the use of color-magnitude diagrams for assessing ages of collections of stars.
His Ph D thesis was on isotope ratios in meteorites, including surface exposure dating.He was employed at Caltech's Division of Geological & Planetary Sciences at the time of writing the first edition.He is presently employed in the Space & Atmospheric Sciences Group at the Los Alamos National Laboratory.In these cases, the age of the first batch of argon released is the age of the reheating event, and the age of the last argon released is the minimum age of initial crystallization.
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. 1979, 1986 © Harper Collins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012 Cite This Source (rā'dē-ō-mět'rĭk) A method for determining the age of an object based on the concentration of a particular radioactive isotope contained within it.
Back in the 1940s, the American chemist Willard Libby used this fact to determine the ages of organisms long dead.