Variable C14/C12 ratio invalidates C14 dating (Talk.Origins)
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- Carbon dating is based on the atmospheric C14/C12 ratio, but that ratio varies. Thus the carbon dating method is not valid.
Source: Morris, Henry M. 1985. Scientific Creationism. Green Forest, AR: Master Books, pp. 162-166.
CreationWiki response: (Talk.Origins quotes in blue)
1. The variability of the C14/C12 ratio, and the need for calibration, has been recognized since 1969]. Calibration is possible by analyzing the C14 content of items dated by independent methods. Dendrochronology (age dating by counting tree rings) has been used to calibrate C14/C12 ratios back more than 11,000 years before the present . C14 dating has been calibrated back more than 30,000 years using uranium-thorium (isochron) dating of corals, and to 45,000 b.p. using U-Th dates of glacial lake varve sediments.
None of the methods of calibration agree. The original content of Carbon 14 can vary by as much as 200% of the current value for the same "date." Furthermore, these calibration efforts eliminate all of these as independent dating methods since they link the various methods such that the assumptions of one affect the results of the other.
Reference: Carbon 14