Clarification – I reference two primary studies in this post. One is the study mentioned by Enyart and Williams in which a “Mosasaur” fossil was C-14 dated at about 25,000 years old. I also speak of the RATE study performed under ICR auspices and headed by John Baumgardner, and which Kirk Bertsche critiqued.
C-14 Contamination
The statement I have heard several times from Enyart and other YECs is that if coal and oil are as old as science claims, then there should be no measurable C-14 left in it. Statements like that are nonsense. It is true that all the C-14 that was in the living organism that eventually became oil or coal would have long decayed away. But except in the rarest of cases, there will be measurable levels of undecayed C-14 in any carbon-bearing sample. I will talk about some of the sources of contamination that keeps a sample from registering its true C-14 age.
In Situ
First is what is termed “in situ” contamination. The term “in situ” literally means “in place” and so most correctly refers to the contamination encountered while the sample is in its natural environment. Sometimes the term “in situ” more generally refers to contamination from all sources right up to it being delivered to the AMS lab for analysis.
Coal and oil, even when deep in the earth, are not always totally isolated from “fresh” C-14. Remember that it takes thousands of years for C-14 to appreciably decay, so any mechanism that could result in atmospheric carbon reaching the sample in ten or more thousand years can alter the sample’s measured C-14 age. Carbon that is used in microbial life can be transported to deep depths by groundwater, or any other mechanism filtering down from the surface. On timescales of ten thousand years most places, even deep ones, get jostled at least a few times by seismic rumblings. Strata that is quiescent now has probably been at least slightly distorted or stretched or deformed.
A second source of in-situ C-14 contamination can be new C-14 formed by native radioactivity in the surrounding strata. Baumgardner claims his calculations show this is far too low to be a significant issue in the sample used for the RATE studies. His penchant for liberally interpreting data at variance with others causes me to distrust his conclusions on this as a C-14 source, at least until I see more impartial scientists concur in this conclusion.
It is very hard to extract oil or coal without exposing it to free air. Carbon has an affinity for absorbing CO2 – as evidenced by the use of finely powered carbon as the air purifying agent in some types of gas masks. Coal mining can involve controlled explosions and drilling, which forces contaminants into strata well before the actual sample is exposed at the wall surface of the mine.
Sample storage between the time of extraction from the earth and delivery to the lab can allow atmospheric C-14 to adsorb into the sample. If the sample is expected to have very little (on no) C-14 in it, then it must be kept in an environment completely free of outside carbon, such as an argon atmosphere.
As it pertains to the article used by Enyart and Williams (
available here), it is clear that the sample handling prior to the C-14 dating is highly suspect. No indication is given in the article of precautions taken to isolate the sample from carbon in the atmosphere, little is said about storage, or what the strata was like where it was found. Since most fossils are not anticipated to undergo C-14 dating, those types of precautions may not have been a concern at all in the early handling of the fossil.
The article says the sample surface was abraded to remove any surface biological contamination that might have accrued. Even that process is unclear as to whether it was done in a standard atmospheric environment where atmospheric-borne carbon might have adhered to newly exposed sample surfaces. Probably the single most telling indication that this sample was not originally handled with the intent of eventually doing a C-14 analysis was the statement that it was “possible that the outer surface of the bone has been painted with animal glue at some point.” That would be horrific contamination for C-14 dating.
To emphasize how crucial careful extraction, storage, and processing of samples suspected of having little C-14 is, note that 40,000 to 50,000 years C-14 age has often been measured on samples known to have no native C-14. This sample came in with a date of 24,600 years, which would be an expected date with about 10 times the contamination that is found on meticulously prepared samples.
Sample Prep
Once the sample is at the AMS lab, it then has to go through some chemical processing before dating, which presents new challenges for contamination. This processing ultimately results in the carbon in the sample combining with oxygen to form CO2, which is then chemically stripped of the oxygen, leaving just the pure carbon. This pure carbon (or a small part of it) is what is inserted into the AMS machine. Excess sample is held in reserve. All of this preparatory handling (known as “carbonization”) needs to be done in a way which keeps new carbon from the sample.
This is one point at which Baumgardner made a misstep. He stated that when the sample is large, then small amounts of contamination during sample preparation are less important, since the contamination would be diluted through the large sample. But Bertsche pointed out that the actual AMS process is not performed on the entirety of large samples. The AMS process routinely only requires a milligram of carbon, and never uses more than about 10 mg, which is far less than the amount the RATE group supplied to the lab.
Variations in the integrity of the sample prep process (chemicals used, glassware, even how the technician preps the sample) can introduce different background C-14 levels.
In his analysis of Baumgardner’s RATE studies, Bertsche made mention of contamination during graphitization (the chemical processing that extracts just the carbon from the sample) often ranges from 0.1 to 0.7 pMC (percent of modern carbon). Baumgardner took strong issue with this value, because that is enough contamination to make RATE’s claims about too much C-14 meaningless. Bertsche responded simply by pointing out where he got those values from – which happened to be studies which Baumgardner himself had referenced in his bibliography.
Measurement
Even the AMS machine itself can contribute to the contamination. Since the AMS process itself involves essentially vaporizing the sample, over time atoms from samples can go astray and adhere to the interior walls of the ionizing chamber. These atoms from prior runs provide a small, but measurable level of contamination. Additionally, small amounts of contamination are expected on the sample holder itself.
Some of these factors vary over time. The same AMS apparatus in a laboratory can be measured to have different background C-14 levels over time.
Baumgardner claimed that to compensate for the C-14 levels due to such sources of contamination, many labs subtract a standard “background” pMC from the measured level. Bertsche pointed out that when the C-14 level is expected to be low, good labs run a “process blank” with the sample. A process blank is a substance containing carbon, but no C-14, and which will undergo the same steps of sample preparation (carbonization) that the real sample will, and will actually be run to see what C-14 level the AMS process gives on it, and should be a pretty good indication of the contamination realized in the sample prep and AMS run.
Summing Up the Contamination Issue
As much as YECs would like to pretend that measured C-14 dates on coal and oil should be “infinite” if they are very old, it just ain’t so. Some AMS systems, if they worked perfectly, were hoped to be able to resolve real C-14 dates of nearly 100,000 years. Baumgardner points to oil and coal dates of 50,000 years from these labs as proof that there is residual C-14 in coal and oil that can only be explained by a recent creation. Bertsche points out that what was hoped for in 100,000 year resolution is not what reality turned out to be. Tests have been run with no sample in the AMS machine that show C-14 dates well below 100,000 years.
Interestingly Bertsche pointed out that ICR itself has an article on-line which disagrees with the thrust of what Baumgardner wants people to believe abut C-14 dating of coal. It is [URL=" http://www.icr.org/article/myths-regarding-radiocarbon-dating/”] available here[/URL]. In that article, Dr. Gerald Aardsma says: “MYTH #4. Samples of coal have been found with radiocarbon ages of only 20,000 radiocarbon years or less, thus proving the recent origin of fossil fuels, probably in the Flood.
I am not aware of any authentic research which supports this claim.” – and - “it is easy to contaminate a sample which contains very little radiocarbon with enough radiocarbon from the research environment to give it an apparent radiocarbon age which is much less than its actual radiocarbon age.” (Dr Aardsma is no longer with ICR. Hmmmmm????)
In answer to Baumgardner’s claim that C-14 dates point to recent creation, Bertsche presents studies where the coal was taken from unusually pristine strata, and meticulously handled thereafter. The measured C-14 dates on some of those samples did in fact reach back close to the values that Baumgardner claims should be the norm. But if creation was recent, there should be no such biologically derived samples that are almost truly C-14 free.
For brevity, I have not touched on several relevant, but peripheral issues. Maybe later. Or not.