We continue the journey…
In 1963 two British scientists, Don Brothwell of the British Museum and Eric Higgs of Cambridge, took stock of the many methods developed up to that time to answer archaeological questions, including dating methods. Only twenty years before that time, nobody would have dreamed of such scientific discoveries relating to the dating of artifacts.
Of all the dating methods, C-14 or radiocarbon dating has created the greatest interest to date. Developed by Willard F. Libby of the University of Chicago — between 1941 and 1945 Libby participated in the development of the atomic bomb — this method of dating has become the touchstone of all fossil dating up to 40,000 years.
Libby postulated that cosmic ray-produced radiocarbon might be a key to age determination. Supposing that C-14 atoms produced by cosmic rays would be readily oxidized to carbon dioxide and would mix freely with the atmospheric carbon dioxide, and because of the rapid turnover of the earth’s atmosphere, Libby assumed the radiocarbon portion of carbon dioxide would achieve uniform global distribution, and would logically be taken up in the same proportion by all plant life during photosynthesis. All animal life, which indirectly or directly lives off of plants and vegetation could also be expected to contain the same UNIVERSAL proportion of C-14. Similarly, even sea life would be thus affected, because carbon dioxide of the atmosphere is in exchange equilibrium with the oceans.
Adds E.H. Willis, “Upon the death of an organism, further uptake or exchange of radiocarbon would cease, leaving the trapped radiocarbon to decay exponentially with time” (Brothwell, Don, and Higgs, Eric, Science in Archaeology: A Comprehensive Survey of Progress and Research).
Simply explained, cosmic rays continually bombard our planet earth. Upon striking our atmosphere, neutrons are produced that react with atoms of nitrogen in our atmosphere, creating tiny quantities of C-14. This newly formed C-14 forms a chemical bond with oxygen as the polymer carbon dioxide. Plants cannot distinguish between carbon dioxide containing radiocarbon and the normal kind and absorb both into their tissues and convert them into food by photosynthesis. Animals and men eat the plants. Thus C-14 passes into the body of every living thing.
Since C-14 is radioactive, and radioactive substances decay at FIXED rates, it is possible to determine that after a specified amount of time the amount of radioactivity in a substance will be reduced exactly one half, or one fourth, and so on. This is called the “half life” of the radioisotope.
The half life of C-14 was at first thought to be 5,567 years. Thus a tree cut down 5,568 years ago theoretically ought to produce only half as many Geiger counter ticks as one chopped down today, because it would have exactly half as much radiocarbon remaining in its tissues.
In January 9, 1948, the first conference took place to study the usefulness of Libby’s method for archaeology. After that time, a flood of materials from the world over poured into Dr. Libby’s lab to be analyzed. Bits of Egyptian mummies, charcoal from an ancient caveman’s fire, the tooth of a mammoth, a piece of a beam of a Hittite temple, and hundreds of other objects, were tested.
Libby’s theory was quickly thought to be confirmed. Comparisons of radiocarbon dates of material with dates derived archaeologically often turned out to be strikingly similar. Although Libby always estimated an uncertainty factor of about ten percent in his datings — thus a piece of wood 4,000 years old would be said to be 4,000 plus or minus about 400 years — Libby’s method helped archaeologists pin down dates which could not otherwise be determined.
It is not possible, however, to give PRECISE radiocarbon dates in practice because of UNCERTAINTIES involved in the measurement of samples. As a result, C-14 dates are always quoted with what is called a “Standard Deviation” which represents their degree of accuracy. “For example, a date of 1,000 BP (Before Present) with a Standard Deviation of fifty years has a 68.3 per cent chance (one Standard Deviation) of lying between 950 and 1,050 BP, a 95.3 per cent chance (two Standard Deviations) of lying between 900 and 1,100 BP, and a 99.8 per cent (three Standard Deviations) of lying between 850 and 1150 BP” (Peter James, Centuries of Darkness. New Jersey: Rutgers University Press, 1991. Appendix I, p. 322).
Unfortunately, a large number of problems have been encountered in applying C-14 dating to ARCHAEOLOGY. First, the vast majority of results have a Standard Deviation greater than 50 years in practice, so that single dates for excavations are of LITTLE VALUE where a century or two is often the scale of the debate. Therefore, the accepted practice today, where C-14 samples are actually taken, is to produce a SERIES of dates for each site.
Second, in certain circumstances OLD CARBON can be absorbed by living organisms and produce radiocarbon dates that are TOO OLD. Notes author Peter James: “For example, VOLCANOES often release OLD CARBON before their eruption, something which may well be a contributory source of CONFUSION in the debate over dating the explosion of Thera [in the Aegean ]” (Ibid., p. 323). The dating of both shellfish and reeds create further problems because they are affected by the presence of OLD CARBON in seawater and freshwater respectively. Ironically, archaeologists tried to apply C-14 dating methods to reeds in Egypt because of their use as a bonding material in the brick walls of temples and tombs.
Several difficulties are encountered when assessing the CLOSENESS of the association between dated samples and the event for which a date is required. Because of its presence in large quantities on most archaeological excavations, CHARCOAL is commonly used to produce the vast majority of radiocarbon dates. This is primarily due to the fact that in acid soils charcoal is usually about the only organic material to survive.
As Peter James explains, “there are TWO distinct problems related to the use of CHARCOAL. One is that large WOODEN BEAMS used for construction may well be fashioned from trees which had grown for several hundred years. If the building is then burnt down, the OUTER PART of the timbers will be destroyed, leaving behind pieces from the CENTRE of the beams. If these remaining sections of the original timbers are then sampled for radiocarbon dating they will give a FALSELY OLD READING…Of course, if the timbers were REUSED from older buildings the discrepancy would be even greater” (Ibid.). Dendrochronologist Peter Kuniholm produced a good example of this when he dated a house in the Phrygian capital on the city mound at Gordion. While one group of timbers had been felled in the 7th century B.C., “three other pieces were cut about FOUR CENTURIES EARLIER. If only the latter had been collected the result would have been an entirely ERRONEOUS notion about the date of [the building]” (Dendrochronology and Radiocarbon Dates for Gordion and Other Phrygian Sites, 1988).
R. B. Warner, writing in the Ulster Journal of Archaeology, explained that the other problem with CHARCOAL SAMPLES is that many C-14 dates have been produced by collecting together large amounts of FRAGMENTARY charcoal. The problem with this is that fragmentary charcoal can easily be moved around sites by continuing activity and differs from bones in that the CONDITION of the sample cannot indicate how QUICKLY it was buried. “The consequence of these two drawbacks is that it has been argued that the estimate of the potential AGE-LAPSE between a sample and the stratum in which it was found should be around 200 years in the case of charcoal from long-lived species of trees” (Peter James, Century of Darkness, p. 324).
In the more recent historic period — the last 2,000 years or so — radiocarbon dates generally agree with historical dates. So with the seeming success of radiocarbon dating in this period, Libby cautiously stated that “in terms of physical principles of course, a method which works for three thousand years might extend all the way to fifty thousand….”
He went on to admit, “However, this is MERE CONJECTURE” (Willard F. Libby, History of Radiocarbon Dating, Symposium on Radioactive Dating and Methods of Low Level Counting, March 1967, p. 24).
He was in for a shock!
Writing in the January 1956 issue of the American Scientist, Dr. Libby briefly related the history of C-14 dating: “The first SHOCK Dr. Arnold and I had was that our advisors informed us that history extended back only 5,000 years.
“We had thought initially that we would be able to get samples all along the curve back to 30,000 years, put the points in, and then our work would be finished.
“You read in the books and find statements that such and such a society or archaeological site is 20,000 years old.
“We learned rather abruptly that these numbers, these ancient ages, are not known; in fact, it is at about the time of the first dynasty of Egypt that the earliest historical date of any real certainty has been established. So we had, in the initial stages, the opportunity to check against knowns, principally EGYPTIAN ARTIFACTS, and in the second stage we had to go into the great wilderness of prehistory to see whether there were elements of internal consistency which would lead one to believe that the method was sound” (Willard F. Libby, “Radiocarbon Dating,” American Scientist, Vol. 44, No. 1, Jan. 1956, p. 107).
But what about the “historical” dates? According to the most liberal estimates Egyptian history begins approximately 5,000 years ago. Some historians, with good reason, believe that Egyptian history does not extend that far into the past. The idea that the various Egyptian dynasties (as recorded by the Egyptian priest Manetho) existed consecutively in time has been seriously questioned by many scholars and is, in fact, totally in ERROR.
This very fact alone has a tremendous bearing on the radiocarbon method of dating. If the dates propagated by the history books are in error, what is there for Libby to hang the accuracy of his dating method on? Without KNOWN historical dates to check an object to be dated against, how can we know for certain that the indicated radiocarbon years are the same as actual calendar years?
And what about dating artifacts OLDER than 5,000 years?
“There was only one way to check the reliability of radiocarbon dating over a longer span,” noted archaeologist Edward S. Deevey, Jr., “and that was to test it on the materials of GEOLOGY and PREHISTORIC ARCHAEOLOGY. The age of such materials is not ‘known’ in the same sense as that of mummy cases or trees [and these are suspect]” (Edward S. Deevey, Jr., “Radiocarbon Dating,” Scientific American, Vol. 186, No. 2, Feb. 1959, p. 25).
The bottom line is that there are no ACCURATE historical dates over 3,000 years with which to check Libby’s dating method. Radiocarbon was entirely alone.
Dr. Libby was forced to make this point clear by heavily QUALIFYING his statements. But most books on evolution — and also history and archaeology — simply gloss over such points as if they didn’t matter. Laymen are led to believe that the radiocarbon dating method is infallible — just like the Pope!
If this was not enough, there is a HUGE ROADBLOCK to the accurate determination of dates using this dating method — C-14 EQUILIBRIUM!
When cosmic-ray particles collide with the earth’s atmosphere, free neutrons are produced that react with nitrogen atoms. A neutron, when it enters the nitrogen nucleus, knocks out a proton — which changes the nitrogen atom to a C-14 atom.
Dr. Libby calculated the PRESENT PRODUCTION RATE of these C-14 atoms, and postulated that if this rate has been going on for thousands upon thousands of years at its PRESENT rate, then the following evidence MUST be found:
“If this production has proceeded at a constant rate for many thousands of years, then the amount of C-14 present on the surface of the earth should reach a CONSTANT value” (“Radiocarbon Dating,” McGraw-Hill Encyclopedia of Science and Technology, 1966 edition, Vol. 11, p. 291).
Libby himself commented on this “constant” value or amount: “…We can see that IF the cosmic rays have been bombarding the earth in essentially THEIR PRESENT INTENSITY for 10 or 20 thousand years, we can expect that a STEADY-STATE CONDITION had been established, in which the rate of formation of carbon-14 is EQUAL to the rate at which it disappears” (Willard F. Libby, “Radiocarbon Dating,” American Scientist, Vol. 44, No. 1, Jan. 1956, p. 99).
If this ASSUMPTION is correct, the C-14 ratio of any ancient specimen or artifact could be related to the PRESENT ratio of C-14 in modern specimens. Dating then becomes very simple. IF NO OTHER UNKNOWN FACTORS had disrupted the method, a radiocarbon year would equal a calendar year.
This EQUILIBRIUM is vital to the theory! The production of C-14 MUST equal the amount leaving the system in disintegration if this method of dating is to be valid. However, it takes a LONG TIME to bring the C-14 level into equilibrium.
If the system is not yet in equilibrium, it simply means that not enough carbon-14 has been produced to match the decay of this atom. It also means that old dates determined by this method would therefore be MUCH MORE RECENT!
Is C-14 equilibrium a fact? Is this dating method viable?
Dr. Libby, and those working with him, estimated that there were 18.8 atoms of radiocarbon being produced every MINUTE, per gram of carbon.
Now, logically, if there were an equilibrium between the rate of production and disintegration, LIVING samples should show a disintegration rate of 18.8 C-14 atoms per minute per gram of carbon.
Can this be verified?
When 18 samples taken from various latitudes were analyzed, they did NOT show an equilibrium! The disintegration rate of the sample only averaged 15.3 disintegrations per minute per gram; therefore the production rate was almost 19 % greater than the rate of disintegration!
Libby himself preferred a value of 16.1 (the value for sea shells) for the disintegration rate — even though the average for organic specimens was 15.3. This still represents a sizable discrepancy — almost 15% between the production rate and the disintegration rate.
Why is it so IMPORTANT to have this equilibrium? Again, Dr. Libby puts his finger on the crucial point:
“If one were to imagine that the cosmic radiation had been turned off until a short while ago, the enormous amount of radiocarbon necessary to the equilibrium state WOULD NOT have been manufactured and the specific radioactivity of living matter would be MUCH LESS than the rate of production calculated from the neutron intensity” (Willard F. Libby, Radiocarbon Dating, Chicago: University of Chicago Press, 1955, p. 8).
Yet, the 18 samples from the various latitudes indicated that equilibrium has NOT YET BEEN REACHED. If this is so, the cosmic system may have been turned on just A SHORT TIME AGO! This, of course, has other implications
The fact is, there simply may not have been enough elapsed time to produce the amount of radiocarbon necessary to bring the system into steady-state equilibrium.
If this is true, how would it affect the radiocarbon dating method?
Now how did Libby overcome this problem in his mind? He answers this very question in his book Radiocarbon Dating: “The agreement seems to be sufficiently within the EXPERIMENTAL ERRORS involved, so that we have reason for confidence in the theoretical picture set forth above” (p. 7).
Is this true — was it just an “experimental error”?
In 1963, a significant report in the journal Reviews of Geophysics was published by geophysicist Richard E. Lingenfelter. With his calculations and conclusions he seemed to put to rest the possibility that the lack of equilibrium was only “experimental error.”
Lingenfelter came to the conclusion that “there is strong indication, despite the large errors, that the present natural production rate EXCEEDS the natural decay rate by as much as 25 percent…it appears that equilibrium in the production and decay of carbon-14 MAY NOT BE MAINTAINED in detail” (Richard E. Lingenfelter, “Production of Carbon-14 by Cosmic Ray Neutrons,” Reviews of Geophysics, Vol. 1, No. 1, Feb. 1963, p. 51).
Some years later, Hans E. Suess commented on Lingenfelter’s experiments by saying: “it seems probable that the present-day inventory of natural C-14 DOES NOT CORRESPOND to the equilibrium value, but is INCREASING” (Journal of Geophysical Research, “Secular Varieties of the Cosmic-ray Produced Carbon-14 in the Atmosphere and Their Interpretations,” Vol. 70, No. 23, Dec. 1, 1965, p. 5947).
Naturally, the evolutionists felt that any discrepancy could be explained without jeopardizing the method. But nonetheless all explanations are still UNPROVED hypotheses.
The production rate seemed to be 20 to 30 percent GREATER than the disintegration rate — depending on what base figures were used.
Many different “explanations” were concocted to rectify this discrepancy but, once again, there was simply NO WAY to be sure! A lack of equilibrium could be a FACT! This could mean there was some DRASTIC CHANGE in the radiocarbon inventory in prehistoric times — such as the period of time mentioned in Genesis 1:2. Was the C-14 system nonfunctional in terms of its effect on the earth until just a short time ago? Have other factors disturbed or changed the crucial C-14-to-ordinary-carbon ratio? Should all the great stretches of time scientists claim for tested fossils be TELESCOPED into a few thousand years? Could it just be possible?
Laboratories around the world continued pouring out thousands of dates. Meanwhile, the layman was convinced that science had proved that relatively recent animal and human fossils were anywhere from 8,000 to 53,000 B.P. (Before the Present). One date of 65,000 B.P. was measured!
However, if the discrepancies are indeed a fact, these dates may have only been 6,000 years old — or younger.
In the meantime, Dr. Lingenfelter pressed forward in his studies of cosmic radiation and its relationship to C-14 production. Despite his positive findings published in 1963, he felt it necessary to RECONSIDER them and, in 1969, made the following admission: “The uncertainties in…the production rate and the inventory are LARGE ENOUGH to accommodate a wide range of Ro [ratio between production and decay of carbon-14] including PERFECT EQUILIBRIUM” (personal communication).
So what it boils down to is that after 50 years scientists still cannot be sure that a BASIC ASSUMPTION of the C-14 dating method is true! They are not even sure of the production rate of radiocarbon!
So why, pray tell me, have thousands of C-14 dates been published as if they are fact? How can newspapers, magazines and school text books be written as though C-14 dating is certain?
Another source of error is inherent in the material. Some aquatic animals have flesh that shows fewer traces of C-14 than their shell. Some plants do not take in as much C-14 as other plants in different environments. Only as enough evidence of these anomalies is accumulated can the errors be corrected.
Another problem is exhaust gases from automobiles. As vast quantities of carbon compounds are belched into the air, diluting the carbon compounds naturally found in the atmosphere, diminishing the percentage of C-14 found there, this makes certain plants and animals in such areas appear to have decayed MUCH MORE than they have.
There are many more sources of MINOR ERROR. Even the “half life” of C-14 has had to undergo revision, and it is now assumed to be 5,730 years. All the measurements taken before 1961, therefore, have had to be recalibrated. Nevertheless, radiocarbon dating has become a KEY tool in the hands of archaeologists. But another highly touted tool, providing a cross check of C-14 dates, is the use of DENDROCHRONOLOGY, or TREE RINGS.