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The C14 technique has been and continues to be applied and used in many, many different fields including hydrology, atmospheric science, oceanography, geology, palaeoclimatology, archaeology and biomedicine.There are three principal isotopes of carbon which occur naturally - C12, C13 (both stable) and C14 (unstable or radioactive).
A sample of acacia wood from the tomb of the pharoah Zoser (or Djoser; 3rd Dynasty, ca. Libby reasoned that since the half-life of C years, they should obtain a C14 concentration of about 50% that which was found in living wood (see Libby, 1949 for further details).
The results they obtained indicated this was the case.
These isotopes are present in the following amounts C12 - 98.89%, C13 - 1.11% and C14 - 0.00000000010%.
Thus, one carbon 14 atom exists in nature for every 1,000,000,000,000 C12 atoms in living material.
14C also enters the Earth's oceans in an atmospheric exchange and as dissolved carbonate (the entire 14C inventory is termed the carbon exchange reservoir (Aitken, 1990)).
Plants and animals which utilise carbon in biological foodchains take up 14C during their lifetimes.
Renfrew (1973) called it 'the radiocarbon revolution' in describing its impact upon the human sciences.
Oakley (1979) suggested its development meant an almost complete re-writing of the evolution and cultural emergence of the human species.
The radiocarbon method is based on the rate of decay of the radioactive or unstable carbon isotope 14 (14C), which is formed in the upper atmosphere through the effect of cosmic ray neutrons upon nitrogen 14.Tags: Adult Dating, affair dating, sex dating