These include: None of these assumptions is strictly correct, beyond a rough first approximation.
Indeed, scientists have now documented that the atmosphere’s concentration of carbon-14 varies considerably according to latitude.
The lecturer talked at length about how inaccurate C14 Dating is (as 'corrected' by dendrochronology).
The methodology is quite accurate, but dendrochronology supposedly shows that the C14 dates go off because of changes in the equilibrium over time, and that the older the dates the larger the error.
You can find some further good information here: -- read the full page if you get the chance.
Conventional geologists claim that fossils, coals, and diamonds are millions to billions of years old.
And this big sequence is then used to 'correct' C14 dates. (3.) Even if the rate of decay is constant, without a knowledge of the exact ratio of C12 to C14 in the initial sample, the dating technique is still subject to question.
Robert Whitelaw has done a very good job illustrating this theory using about 30,000 dates published in Radio Carbon over the last 40 years.If you have any more questions about it don't hesitate to write.(2.) I just listened to a series of lectures on archaeology put out by John Hopkins Univ.Libby, the discoverer of the C14 dating method, was very disappointed with this problem.He understood that archaeological artifacts were readily available.So they tested some of the ring sequences by C14 to put the sequences in the 'right' order.