How accurate are Carbon-14 and other radioactive dating methods?
Their recent analysis of sediment from the largest freshwater lake in northeast China showed that its carbon clock stopped ticking as early as 30, years ago, or nearly half as long as was hitherto thought. For instance, remnants of organic matter formerly held up as solid evidence wronb the most recent, large-scale global warming event some 40, years ago may actually date back far earlier to a previous ice age. Their work was detailed in a paper in the latest issue of the journal Earth and Planetary Science Letters.
For over 50 years, scientists and researchers have relied on carbon dating to find the exact age of organic matter. Prior to that, they had to depend on more rudimentary and imprecise methods, can radiocarbon dating wrong as counting the number of rings on a cross-section of tree trunk. This gadiocarbon changed in the s when US chemist Willard Libby discovered that czn, a radioactive isotope, could be used to date can radiocarbon dating wrong compounds.
His theory was that all living creatures have a constant proportion of radioactive and non-radioactive carbons in their body because they keep absorbing these elements from the environment. But as soon as the creature dies it stops absorbing these and sheds any trace of carbon at a decay rate of 50 per can radiocarbon dating wrong every 5, years. By measuring the remaining amount of carbon in a sample, radiocarbom could estimate the time of death up to 60, years ago.
But the method had one major flaw: In the new study using samples taken from Xingkai Lake near the Sino-Russian border in Heilongjiang province, the scientists used both radiocarbon dating and another method known as optically stimulated luminescence. Using light to measure the amount of free electrons trapped in quartz, the team was able to tell how long the samples had been kept raeiocarbon from sunlight, and therefore estimate when it was that they first fell in the lake.
By comparing cab from the two methods, they found that carbon dating became unreliable beyond a range of 30, years. The great lakes are widely believed to have appeared in China due to massive melting of ice sheets during an exceptionally warm period some 40, years ago, and sediment from Xingkai Lake served as key evidence. But the new study suggests that the sediment might be over 80, years old, possibly formed during an ice age.
Skip to main content. South China Morning Post Edition: International Hong Kong International. Jobs Events Education Courses Newsletters. Main menu Home China HK Asia World Comment Business Tech Life Culture Sport Week in asia Post Can radiocarbon dating wrong Style. South China Morning Post Main menu China HK Asia World Comment Business Tech Life Culture Sport Week in can radiocarbon dating wrong Post Mag Style.
Now Reading Many global warming studies may be wrong as carbon dating found to be highly unreliable for organic matter over 30, years old. Sport Hong Kong China Golf Racing Rugby HK Sevens Soccer Tennis Boxing Motorsport. Multimedia Infographics Photos Video. Magazines Post Magazine Style Good Eating Destination Macau. Around The Nation South China Sea: Hague case Cathay Pacific Jake's View A-shares. Advertising Solutions SCMP Mobile Edition SCMP Tablet Edition SCMP can radiocarbon dating wrong Edition SCMP.
Many global warming studies may be wrong as carbon dating found to be highly unreliable for organic matter over 30, years old. Wednesday, 09 September,7: Before that, all traces of radiocarbon would be too small to detect. Thank you You are on the list. Most Popular Viewed 1. NASA to shoot coloured clouds into space.
Only the adaptable thrives in the new landscape can radiocarbon dating wrong asset management. Why Hong Kong still has the edge over Singapore, London. Hong Kong is failing to adapt to changing times, technology. Uber issue is about politics, not about defying regulation. Order your FREE copy of AT YOUR SERVICE