Radiocarbon Dating - Inaccurate & Questionable Results.

Can the results obtained from the 'scientific' Radio-Carbon Dating , be used for a reliable re-construction of History ? 

The systemic flaws in Radio-Carbon dating is detailed by Jared Diamond in his book Guns, Germs & Steel. The relevant excerpt from the book is given below.

"Archaeologists date food production by radiocarbon dating of carbon containing materials at the site.

This method is based on the slow decay of radioactive carbon 14, a very minor component of carbon, the ubiquitous building block of life, into the nonradioactive isotope nitrogen 14. Carbon14 is continually being generated in the atmosphere by cosmic rays. Plants take up atmospheric carbon, which has a known and approximately constant ratio of carbon 14 to the prevalent isotope carbon 12 (a ratio of about one to a million). That plant carbon goes on to form the body of the herbivorous animals that eat the plants, and of the carnivorous animals that eat those herbivorous animals. Once the plant or animal dies, though, half of its carbon 14 content decays into carbon 12 every 5,700 years, until after about 40,000 years the carbon 14 content is very low and difficult to measure or to distinguish from contamination with small amounts of modern materials containing carbon 14. Hence the age of material from an archaeological site can be calculated from the material's carbon 14/carbon12 ratio.

 

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Radiocarbon is plagued by numerous technical problems, of which two deserve mention here. One is that radiocarbon dating until the 1980s required relatively large amounts of carbon (a few grams), much more than the amount in small seeds or bones. Hence scientists instead often had to resort to dating material recovered nearby at the same site andbelieved to be "associated with" the food remains—that is, to have been deposited simultaneously by the people who left the food. A typical choice of "associated" material is charcoal from fires.

But archaeological sites are not always neatly sealed time capsules of  materials all deposited on the same day. Materials deposited at different times can get mixed together, as worms and rodents and other agents churn up the ground. Charcoal residues from a fire can thereby end up close to the remains of a plant or animal that died and was eaten thousands of years earlier or later. Increasingly today, archaeologists are circumventing this problem by a new technique termed accelerator mass spectrometry, which permits radiocarbon dating of tiny samples and thus lets one directly date a single small seed, small bone, or other food residue. In some cases big differences have been found between recent radiocarbon dates based on the direct new methods (which have their own problems) and those based on the indirect older ones. Among the resulting controversies remaining unresolved, perhaps the most important for the purposes of this book concerns the date when food production originated in the Americas: indirect methods of the 1960s and 1970s yielded dates as early as 7000 B.C., but more recent direct dating has been yielding dates no earlier than 3500 B.C.

A second problem in radiocarbon dating is that the carbon 14 / carbon12 ratio of the atmosphere is in fact not rigidly constant but fluctuates slightly with time, so calculations of radiocarbon dates based on the assumption of a constant ratio are subject to small systematic errors. The magnitude of this error for each past date can in principle be determined with the help of long-lived trees laying down annual growth rings, since the rings can be counted up to obtain an absolute calendar date in the past for each ring, and a carbon sample of wood dated in this manner can then be analyzed for its carbon 14 / carbon 12 ratio. In this way, measured radiocarbon dates can be "calibrated" to take account of fluctuations in the atmospheric carbon ratio. The effect of this correction is that, for materials with apparent (that is, uncalibrated) dates between about 1000 and 6000 B.C., the true (calibrated) date is between a few centuries and a thousand years earlier. Somewhat older samples have more recently begun to be calibrated by an alternative method based on another radioactive decay process and yielding the conclusion that samples apparently dating to about 9000 B.C. actually date to around 11,000 B.C.

Archaeologists often distinguish calibrated from uncalibrated dates by writing the former in upper-case letters and the latter in lower-case letters (for example, 3000 B.C. vs. 3000 b.c., respectively). However, the archaeological literature can be confusing in this respect, because many books and papers report uncalibrated dates as B.C. and fail to mention that they are actually uncalibrated. The dates that I report in this book for events within the last 15,000 years are calibrated dates. That accounts for some of the discrepancies that readers may note between this book's dates and those

quoted in some standard reference books on early food production."

From the Book -GUNS, GERMS, AND STEEL, Chapter 5, HISTORY'S HAVES AND HAVE-NOTS , pages 95-97

For further reference two links are provided. The first one is linked to a Christian Organization.
(1) http://www.hydrogen2oxygen.net/en/radiocarbon-dating-and-its-limitation-regarding-the-preflood-world/
(2) http://science.howstuffworks.com/environmental/earth/geology/radiocarbon-dating-change-archaeology.htm