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As I recall, there's also an issue with radio-carbon dating anything after atmospheric atomic weapons testing commenced.
by sbuttgereit 7y ago
As I recall, there's also an issue with radio-carbon dating anything after atmospheric atomic weapons testing commenced.
- Someone 7y agoThat problem started earlier, when we started burning significant quantities of coal. https://en.wikipedia.org/wiki/Radiocarbon_dating https://en.wikipedia.org/wiki/Radiocarbon_dating: ”Research has been ongoing since the 1960s to determine what the proportion of 14C in the atmosphere has been over the past fifty thousand years. The resulting data, in the form of a calibration curve, is now used to convert a given measurement of radiocarbon in a sample into an estimate of the sample's calendar age […] Because the time it takes to convert biological materials to fossil fuels is substantially longer than the time it takes for its 14C to decay below detectable levels, fossil fuels contain almost no 14C, and as a result there was a noticeable drop in the proportion of 14C in the atmosphere beginning in the late 19th century. Conversely, nuclear testing increased the amount of 14C in the atmosphere, which attained a maximum in about 1965 of almost twice what it had been before the testing began.”