Radioactive carbon dating and radiometric dating
The object's approximate age can then be figured out using the known rate of decay of the isotope.For organic materials, the comparison is between the current ratio of a radioactive isotope to a stable isotope of the same element and the known ratio of the two isotopes in living organisms.
To see how we actually use this information to date rocks, consider the following: Usually, we know the amount, N, of an isotope present today, and the amount of a daughter element produced by decay, D*.Other corrections must be made to account for the proportion of throughout the biosphere (reservoir effects).Additional complications come from the burning of fossil fuels such as coal and oil, and from the above-ground nuclear tests done in the 1950s and 1960s. The method was developed by Willard Libby in the late 1940s and soon became a standard tool for archaeologists.Libby received the Nobel Prize in Chemistry for his work in 1960.There are over forty such techniques, each using a different radioactive element or a different way of measuring them.
It has become increasingly clear that these radiometric dating techniques agree with each other and as a whole, present a coherent picture in which the Earth was created a very long time ago.
Further evidence comes from the complete agreement between radiometric dates and other dating methods such as counting tree rings or glacier ice core layers.
Many Christians have been led to distrust radiometric dating and are completely unaware of the great number of laboratory measurements that have shown these methods to be consistent.
The radiocarbon dating method is based on the fact that radiocarbon is constantly being created in the atmosphere by the interaction of cosmic rays with atmospheric nitrogen.
The resulting radiocarbon combines with atmospheric oxygen to form radioactive carbon dioxide, which is incorporated into plants by photosynthesis; animals then acquire in a sample from a dead plant or animal such as a piece of wood or a fragment of bone provides information that can be used to calculate when the animal or plant died.
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.