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The procedures used to isolate and analyze the parent and daughter nuclides must be precise and accurate.This normally involves isotope-ratio mass spectrometry. The precision of a dating method depends in part on the half-life of the radioactive isotope involved.The temperature at which this happens is known as the closure temperature or blocking temperature and is specific to a particular material and isotopic system.These temperatures are experimentally determined in the lab by artificially resetting sample minerals using a high-temperature furnace.Radiometric dating or radioactive dating is a technique used to date materials such as rocks or carbon, in which trace radioactive impurities were selectively incorporated when they were formed.The method compares the abundance of a naturally occurring radioactive isotope within the material to the abundance of its decay products, which form at a known constant rate of decay.
By allowing the establishment of geological timescales, it provides a significant source of information about the ages of fossils and the deduced rates of evolutionary change.This predictability allows the relative abundances of related nuclides to be used as a clock to measure the time from the incorporation of the original nuclides into a material to the present.The basic equation of radiometric dating requires that neither the parent nuclide nor the daughter product can enter or leave the material after its formation.For instance, carbon-14 has a half-life of 5,730 years.After an organism has been dead for 60,000 years, so little carbon-14 is left that accurate dating can not be established.
Finally, correlation between different isotopic dating methods may be required to confirm the age of a sample.