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The preferred method of dating dinosaur fossils is with the radiometric dating method. And the result of this accepted method dates dinosaur fossils to around 68 million years old.

However: Consider the C-14 decay rate. Its half-life ($t_{1/2}$) is only 5,730 years—that is, every 5,730 years, half of it decays away. The theoretical limit for C-14 dating is 100,000 years using AMS, but for practical purposes it is 45,000 to 55,000 years. If dinosaur bones are 65 million years old, there should not be one atom of C-14 left in them.

Dinosaurs are not dated with Carbon-14, yet some researchers have claimed that there is still Carbon-14 in the bones.

So what needs to be done about this inconsistency? Do these data indicate that a more accurate method needs to be derived? What solutions are available for increasing accuracy of the tests? Or do we need another dating method all together?

Considering Contamination

From the source linked above:

Carbon-14 is considered to be a highly reliable dating technique. It's accuracy has been verified by using C-14 to date artifacts whose age is known historically. The fluctuation of the amount of C-14 in the atmosphere over time adds a small uncertainty, but contamination by "modern carbon" such as decayed organic matter from soils poses a greater possibility for error.

Dr. Thomas Seiler, a physicist from Germany, gave the presentation in Singapore. He said that his team and the laboratories they employed took special care to avoid contamination. That included protecting the samples, avoiding cracked areas in the bones, and meticulous pre-cleaning of the samples with chemicals to remove possible contaminants. Knowing that small concentrations of collagen can attract contamination, they compared precision Accelerator Mass Spectrometry (AMS) tests of collagen and bioapatite (hard carbonate bone mineral) with conventional counting methods of large bone fragments from the same dinosaurs. "Comparing such different molecules as minerals and organics from the same bone region, we obtained concordant C-14 results which were well below the upper limits of C-14 dating. These, together with many other remarkable concordances between samples from different fossils, geographic regions and stratigraphic positions make random contamination as origin of the C-14 unlikely".

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There is a lot of discussion about this issue on this internet, so I think this question may be worth addressing seriously. The main point of the debate seems to be the following:

Over the past decades, several research groups of self-proclaimed creationist scientists have claimed discoveries of dinosaur bones that they have managed to date, using radiocarbon dating methods, at some age which is a lot below the 'usual' i.e. mainstream accepted date for the age of these bones (several dozens of million years old). The age that these groups claim to find is usually on the order of thousands or tens of thousands of years old. The particular example you bring up is one of the most famous such cases. The claims are really quite spectacular, when taken at face value, and therefore should be examined thoroughly. In this answer, I will try to go through this story in great detail, (hopefully) exposing the reasons why this work is not taken seriously by scientists.

The research by Miller et al.

A research team from the CRSEF, or Creation Research, Science Education Foundation, led by Hugh Miller, has claimed to have dated dinosaur bones using radiocarbon methods, determining them to be no older than several dozens of thousands of years old. Let's look at their research methodology in detail (indicated by bullet points):

  • As it turns out, Miller's research group obtained their sample in quite a remarkable way. In fact, the creationist posed as chemists in order to secure a number of fragments of fossilized dinosaur bone from a museum of natural history, misrepresenting their own research in the process of doing so.

  • When the museum provided the bone fragments, they emphasized that they had been heavily contaminated with "shellac" and other chemical preservatives. Miller and his group accepted the samples and reassured the museum that such containments would not be problematic for the analysis at hand. They then sent it to a laboratory run by the University of Arizona, where radiocarbon dating could be carried out. To get the scientists to consider their sample, the researchers once again pretended to be interested in the dating for general chemical analysis purposes, misrepresenting their research.

Let's take a little pause to consider the general issue of misrepresenting your own research. It is understandable that Miller et al. did this, since there would have been a slim chance (at best) of the museum curator providing them with any dinosaur bone fragments if he or she had known what the true intent of the supposed chemists was. In particular, it is implausible that it would have been considered worthwhile to try to use radiocarbon dating methods on these bones, since the rocks that they were taken from were determined to be 99+ million years old, as shown in this paper by Kowallis et al. Now, it is known that $^{14}\text{C}$ decays at a fast enough rate (half-life ~6000 years) for this dating method to be absolutely useless on such samples. Thus, it appears that Miller et al. would not have been able to obtain this sample, had they been honest about their intent. This, of course, raises some ethical questions, but let's brush these aside for now. We proceed with the examination of the research done by Miller and his fellow researchers from the CRSEF.

What exactly are we dating here? Sample contamination and general trustworthyness

  • After the samples were submitted by the laboratory, Miller et al. were informed by a professor from the University of Arizona that the samples were heavily contaminated, and that no collagen (where most of the carbon for $^{14}\text{C}$ dating comes from) was present. Miller let assured the professor that the analysis was still of interest to the group. The issue of contaminations is quite a serious one, as can be seen in this paper by Hedges and Gowlett (sorry, paywalled!!!). I quote (quote also reproduced in the paper by Lepper that I linked earlier:

At a horizon of 40,000 years the amount of carbon 14 in a bone or a piece of charcoal can be truly minute: such a specimen may contain only a few thousand 14C atoms. Consequently equally small quantities of modern carbon can severely skew the measurements. Contamination of this kind amounting to 1 percent of the carbon in a sample 25,000 years old would make it appear to be about 1,500 years younger than its actual age. Such contamination would, however, reduce the apparent age of a 60,000-year-old object by almost 50 percent. Clearly proper sample decontamination procedures are of particular importance in the dating of very old artifacts

It is clear that the sample provided by Miller did not under go any 'sample decontamination procedures' at all, and it is therefore strongly questionable to which extent it can be used to obtain a good estimate of the age of the bones. Furthermore, it appears less than certain that the carbon found in the bones actually had anything to do with them being dinosaur bones. In the article by Leppert, we find:

Hugh Miller generously provided me with a copy of the elemental analysis of one of their dinosaur fossils. Daniel Fisher of the University of Michigan’s Museum of Paleontology examined these results and concludes that there is nothing whatsoever extraordinary about them. The predominant suite of elements present and their relative percentages (including the 3.4% carbon!) are about what one would expect to find in hydroxyapatite and calcite, two of the commonest minerals present in ordinary dinosaur fossils. There is absolutely nothing unusual about these fossils and no reason to think the carbon contained in them is organic carbon derived from the original dinosaur bone.

Robert Kalin senior research specialist at the University of Arizona’s radiocarbon dating laboratory, performed a standard independent analysis of the specimens submitted by Hugh Miller and concluded that the samples identified as “bones” did not contain any collagen. They were, in fact, not bone.

These results corroborated established paleontological theories that assert that these fossiles presumably were 'washed away' over long periods of time by ground water, replacing the original bones with other substances such as the minerals naturally present in the water, implying that this sample could not tell you anything about when a dinosaur lived (or rather, died).

Conclusions

At this point, it is quite clear that there is little reason to trust the research by Miller's research group. In fact, the article by Leppert raises a number of additional issues (e.g. Miller's group refuses to reveal where some other samples of theirs were dated), but I think it is pointless to argue further: It is obvious that the CRSEF research group did a poor job in sticking to the scientific method, and that little objective value can be assigned to their supposed findings.

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    $\begingroup$ I'm not sure why we bothered to answer. Creationists demonstrably don't care about the facts. I'd be honestly surprised if this wasn't a troll. $\endgroup$ – Goodies Dec 23 '14 at 6:56
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    $\begingroup$ @Goodies It's probably good to have an in-depth, serious discussion about why one shouldn't believe these guys. $\endgroup$ – Danu Dec 23 '14 at 7:13
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    $\begingroup$ This answer provides no solution for increasing accuracy of the tests. $\endgroup$ – Decrypted Dec 23 '14 at 12:40
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    $\begingroup$ @Onlyheisgood The point is not that the method is wrong. It just appears that these people tried to apply the method - doing so in a very sloppy way, as I showed - for which is is of no use. $\endgroup$ – Danu Dec 24 '14 at 23:08
  • $\begingroup$ geology.byu.edu/drupal/sites/default/files/… is a 404 link $\endgroup$ – M.M Jan 25 at 0:50
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I actually happen to know something about the "Miller Tale" as it is called. Miller "borrowed" some dinosaur bones from a museum without telling the curators or owners what he was actually intending on doing with it. He immediately took it to be $^{14}C$ dated and received a date of roughly 40,000 years. So if Dinosaur bones are supposedly 65+ million years old, why is this? I'll tell you why.

The dinosaur bones did NOT have any carbon in them. They'd been essentially completely replaced by minerals during the fossilization process. What happened was that Miller did NOT know that they were covered in a preservative made of an organic material called shellac, which is organic so it's full of carbon. This contaminated the result. What they got was a date for the shellac, not the dinosaur fossils.

Onto your questions:

  • So what research is being done to correct such an obvious dating flaw?
    The flaw is with creationists. We've been trying to educate creationists for decades now, but willful ignorance in favor of adhering to tradition and presuppositions is far stronger than anything that can be taught.
  • Using this data, can a more accurate method be derived?
    Yes! We have dozens of independent dating methods that have accurately dated the layers of dinosaur fossils to a very high degree of accuracy. We have also used isochron dating to test for contamination and/or how well the rocks acted as closed systems.
  • Or do we need another dating method all together?
    Carbon dating is very accurate. I recommend you check out This Paper from 1949. It shows that objects of known age via independent methods and recordings are corroborated by carbon dating.
  • At what extremes of failure does it take for a scientifically approved method to become nonscientific?
    At the point at which it can be shown to be false and lack point of predictive capability. An ignorant creationist who lacks an understanding of radiometric dating does not constitute evidence against a well-established and well-understood process.
  • And what does it say about science if dating something as 65 million years old when it is less then 100,000 years old becomes an acceptable margin of error?
    I'd answer this if it were true. Unfortunately, as I said, the ignorance of creationists does not constitute evidence against radiometric dating by any stretch of the imagination.

I know this was incredibly simple and largely unscientific, but I'm dealing only with your creationist claim. I didn't know this claim was still out there. Got any other questions on radiometric dating?

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    $\begingroup$ Small note: Miller did know they were covered in shellac (see the Leppert paper). $\endgroup$ – Danu Dec 23 '14 at 7:56
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    $\begingroup$ This answer provides no solution for increasing accuracy of the tests. $\endgroup$ – Decrypted Dec 23 '14 at 12:43
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    $\begingroup$ I think this would actually address OPs main issue (a "more accurate" radiometric test) if you expanded on bullet points 2 & 3, making them the central point, rather than debunking the creationist claims. $\endgroup$ – Kyle Kanos Dec 23 '14 at 14:01

protected by Qmechanic Nov 5 '15 at 11:27

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