Chat room sexy balck women gratuite - Chemical dating techniques
Absolute dating is the process of determining an age on a specified chronology in archaeology and geology.Some scientists prefer the terms chronometric or calendar dating, as use of the word "absolute" implies an unwarranted certainty of accuracy.One of the most widely used is potassium–argon dating (K–Ar dating).
K–Ar dating was used to calibrate the geomagnetic polarity time scale.
Thermoluminescence testing also dates items to the last time they were heated.
The development of accelerator mass spectrometry (AMS) dating, which allows a date to be obtained from a very small sample, has been very useful in this regard.
Other radiometric dating techniques are available for earlier periods.
The relatively short half-life of carbon-14, 5,730 years, makes dating reliable only up to about 50,000 years.