Carbon 14 dating wikianswers
The method is known as bomb pulse dating and owes its efficacy to the large amount of $^$C that entered the atmosphere as a result of the testing of nuclear weapons.The $^$C atmospheric abundance peaked in the early to mid-1960s at around twice the longer-term average and has since declined pseudo-exponentially with an e-folding time of around 15 years.I am a paintings conservator and have been requested to examine a panel painting from approximately 1550 A.D., and I have dendrochronological evidence which supports this date.They believe that neutron radiation caused by an earthquake could have induced the image of a crucified man -- which many people believe to be that of Jesus -- onto the length of linen cloth, and caused Paul Carlsson, a paleometagenomicist working to establish his own career after an abusive childhood at the hands of his scientist father, has never known a world that wasn't 5,800 years old--a figure that, according to his father, had been proven by the Shroud of Turin, the magic bullet and the Kennedy assassination, Romanov bones and DNA matches, Hitler's skull, tracking the killer virus of 1918, testing the Titanic rivets, and identifying Osama bin Laden.
The technique is still a potent one; the modern, recalibrated version makes adjustments for the historical fluctuations of carbon in the atmosphere and other conditions.Carbon-14 is continually formed in nature by the interaction of neutrons with nitrogen-14 in the Earth’s atmosphere; the neutrons required for this reaction are produced by cosmic rays interacting with the atmosphere.Radiocarbon present in molecules of atmospheric carbon dioxide enters the biological carbon cycle: it is absorbed from the air by green plants and then passed on to animals through the food chain.Given this, I see no reason why radio-carbon dating cannot be used for material that is 500 years old, since that should result in a $^$C/$^$C ratio change of order 10 percent which is several times larger than the natural variation.
However, if I interpret the plot above correctly, because the natural $^$C abundance was decreasing between 15 (and perhaps before this too?
I also understand the concerns with carbon-14 dating regarding the impact of fossil fuels / atomic activity in recent dating attempts.