Indeed, by doing almost 20 seconds of research on google (type in “variations in C14”, click on Google Scholar) the second link is this article from 1954: Carbon 13 in plants and the relationships between carbon 13 and carbon 14 variations in nature So, this issue has been known about for a long time. Then we compare the two and adjust the radiocarbon date to the known date. That’s less than 1% if you’re interested in that sort of thing. But this is already almost a thousand words and I’ve only done ONE! Long story short, scientists have always known that variations in C-14 concentration happen.
It might take a millisecond, or it might take a century. But if you have a large enough sample, a pattern begins to emerge.Scientists use two kinds of dating techniques to work out the age of rocks and fossils. This considers the positions of the different rocks in sequence (in relation to each other) and the different types of fossil that are found in them.The second method is called absolute dating and is done by analysing the amount of radioactive decay in the minerals of the rocks.Scientists, using rigorous methods have established a process to eliminate this problem by calibrating radiocarbon dating results to items of a known age.In this way, items of unknown age can be tested and an age determined to a reasonable degree of accuracy. More tomorrow where we explore the concept of isochron dating and how it neatly destroys most of the rest of these ‘issues’.