C14 has a half life of years and is only good to date objects to 50, years or so. Although I can find any number of references to this seemingly vital finding on the creationist sites, I can find almost no attempt to refute or explain this anomaly on serious science sites. This looks like a serious oversight to me. There seem to be some unsubstantiated references to the possibility of neutrons generated by uranium decay resulting in an anomalously high presence of C The small apparent non-zero values are less than measurement error.
In other words, the readings are consistent with zero C14 content. In fact, the experiments cited by the creationists appear to be attempts to establish the measurement error of there equipment. Older carbon dating techniques directly detected decays of C14 atoms. If the material is too old, the small amount of C14 present may not decay in the measurement interval.
Newer, more accurate techniques use mass spectroscopy. Mass spectroscopy, like any man-made measurement, is not perfect. In particular, given a pure sample of C12, I suspect a mass spectrometer would indicate that a non-zero amount of C14 present. It is nigh impossible to measure exactly zero.
Feedback archive → Feedback More on radioactive dating problems A further response to Reasonable Faith Adelaide owumubafifam.ml Most people think that radioactive dating has proven the earth is billions of years old. Yet this view is based on a misunderstanding of how.
It doesn't take much contamination to spoil a sample with near-zero quantity of C Creationists pounce on this explanation as meaning all carbon 14 readings are suspect. While that same level of contamination if this is the explanation will add some error to the dating of some reasonably aged sample, the error will be small -- so long as the sample is not too old. The contamination is additive, not proportional. Alternate source of C14 production.
Natural diamonds are not pure carbon. The most common contaminant is nitrogen, 0. Nearby radioactive material could trigger exactly the same C14 production process from nitrogen as occurs in the upper atmosphere, albeit at a much reduced rate. Another possible avenue is C13, which has a small but non-zero neutron absorption cross section. By either mechanism, this is essentially internal contamination.
All this means is that measured dates older than some oldest reliable date are just that -- to old to date reliably. I might be able to see if I can come up with some references. I won't be able to do so in the near term -- my wife and kids want me to stop dorking with the internet and go out to eat. The article you were looking for is here , and yeah, it looks like you're right.
Here is a very detailed explanation: I think that should be I know I visited talkorigins. What is more alarming is that the Google searches for "carbon 14 RATE", "carbon 14 diamond", and "carbon 14 coal" yield hits predominantly in woowoo fundamentalist sites, and no hits on the first 15 pages 10 links per page to anything at talkorigins. I eventually managed to find an excellent article see the top of this post using pandasthumb.
That led me to this non-technical article,. I think the news item on their front page refers to a much older event. What happened, from what I recall, is that someone hacked TalkOrigins and managed to get the site to display hidden spam links at the bottom of pages, making Google think it was a spam site and thus getting it removed from Google.
They fixed that issue a while ago. PZ Myers says they've had some technical issues. I am working my way through Kirk Bertsche's 9 page essay on the subject. Thanks DH for this link.
This article does a good job at explaining the technical complexities of measuring the very small amounts of C14 present in these ancient samples and why non-zero amounts are measured. I'm a complete non-expert in this field of radiometric dating, but it strikes me reading this how contamination by modern carbon introduced during sample preparation seems to be a severe issue.
I'm wonder whether they've extracted samples under an inert atmosphere and then used laser ablation to ionize samples in their mass spectrometers?
I'm probably teaching grandmother to suck eggs, as the old saying goes. Getting back to my OP - I feel that some definitive work needs to be done in this area. It's easy to see that the sceptical creationist is simply going to see the scientific response as making excuses for the data instead of holding up some hard data that either explains or explodes the anomaly.
Another thing I've heard from creationists is that fossils made by soaking samples in tar pits appear to be extremely old. Of course, the problem is that this process results in contamination with old carbon, making the sample appear older. In the case of old samples with almost no C, even the tiniest bit of contamination would make the sample appear far younger. Always remember that C dating is not a magical process; it is a measure of C and the age interpretation depends on a few assumptions. It's also worth noting that C is only useful for a bit more than , years.
The vast majority of fossils aren't dated using C at all, but other radioisotopes. Science has several very reasonable explanations for levels of modern carbon in very old samples. Although this satisfies the scientist, who for all sorts of other reasons quite reasonably assumes that these samples are truly old, it leaves enormous scope for the creationists to reinforce their followers' faith that the earth is young.
I still feel that some definitive experiments in this area would be useful to test the various rational explanations for the c14 anomaly. Hayes has brought it up, we can take it into account, right? If the effects of diffusion can be taken into account, it will require an elaborate model that will most certainly require elaborate assumptions. Hayes suggests a couple of other approaches that might work, but its not clear how well. So what does this mean? If you believe the earth is very old, then most likely, all of the radioactive dates based on isochrons are probably overestimates.
How bad are the overestimates? Most likely, the effect will be dependent on the age. I would think that the older the sample, the larger the overestimate. As a young-earth creationist, I look at this issue in a different way. Certainly not enough to justify the incredibly unscientific extrapolation necessary in an old-earth framework.
This newly-pointed-out flaw in the isochron method is a stark reminder of that. A good isochron was supposed to be rock-solid evidence pun intended that the radioactive date is reliable. We now know that it is not. Wile, I was waiting for you to comment on this, because I wanted to ask if you think this problem can be extrapolated to other isotopes such as lead and argon.
If so, it seems to be a pretty big deal. As I said, carbon dating is an exception, but most other modern radiometric dates are produced using an isochron. Are the samples we see in the RATE study, for example, just anomalies, existing on the ends of the bell curve, or are these indicative of an endemic misunderstanding of the process? Are there any theories that could account for the accelerated decay rate or how the daughters could have gotten in to the samples? Thus, any significant amount of daughter product will produce a very old date.
In my view, if two different dating schemes give significantly different answers, then either one of them is wrong or both of them are wrong. Scientists exclude what we think are anomalous data all the time. Unfortunately, that discarded data might be what gives us real insight. Young-earth creationists have a hard time explaining the general results of long-lived isotopes and their daughter products being present. On the other side, old-earthers have a hard time explaining all the discordance. If radioactive dating is so reliable, why do different methods yield different results?
Why are some of those differences really, really large? As is often the case, there are problems on both sides. The side you end up coming down on often depends on which problems you are most comfortable trying to deal with. Physicists already theorize that dark matter would affect nuclear decay rates; what if the leftover energy went to the dark matter?
The heat problem occurs everywhere there are radioactive isotopes, so throughout the crust and mantle of the earth, for example. The dark matter would have to be there in order to take the heat. You can think of dark matter here as a lot like the luminiferous ether: Since its interaction with normal matter is incredibly weak, it can very easily pass through the earth.
Not to mention that different models of dark matter would lead to different interactions. Are we able to calculate the mass of the earth from our knowledge of its contents, and not just the gravitational force we detect? I think if there were much dark matter in the earth, it would be noticeable. We also know the overall composition of the crust and mantle from samples. Thus, the only real unknown is the composition of the core. Using the mass and all those other measurements, we deduce that the core is mostly iron with some nickel.
I fear it is more a matter of philosophy rather than hard science: The problem with that, is that, in the first case, there appear to be no transitional fossils when there should be millions , and to make the assumption previously herein stated, evolutionary conclusions are more akin to a combination of wishful thinking combined with a sympathetic magic mindset, than to observable examples. Evolution is taught as established fact, and scientific enquiry is severely trammelled by those who prefer a status quo.
Every fossil between organisms alive now and abiogenesis is a transitional fossil, Tony. There are also transitional fossils and organisms in the misguided definition of the word you are using. I admire your faith, Cromwell. Yet you state it as fact. Then, you claim that all fossils are a transition between that unrealistic event and the life we see now. Thanks for writing an informative article. Error bars have their place, but you are correct in pointing out that they are often misunderstood not only by the general public, but by scientists who are not savvy in radiometric dating. I would have worded this sentence differently: I am not convinced that differential diffusion of isotopes will be all that significant.
After all, fractionation of light elements, such as oxygen, provides us with all sorts of insights into geologic processes because the mass difference between O and O is rather significant, whereas the mass difference between Sr and Sr is not all that great, in terms of ratios. The differences are even less significant for more massive isotopes such as in samarium-neodymium dating Nd and Nd If fractionation does turn out to be important for isochrons, one would expect that there would be a trend, with lighter nuclides e.
Rb-Sr being more affected than heavier nuclides e. I am also wondering if Dr. Hays addressed how isotope fractionation would affect U-series concordia diagrams. As it is, there is a general correlation of dates obtained by radiometric dating from the top to the bottom of the geologic column. Strongly discordant dates happen and young-Earth creationists focus on these , but roughly concordant dates are common; otherwise geologists would not trust the methods. It seems strange, if diffusion is a problem, that nuclides with very different masses are effected in the same way. Perhaps Earth is only 3.
This would require similar diffusion rates in cold meteorites as in warm crustal zircons.
Radiometric dating of rocks and minerals using naturally occurring, long-lived radioactive isotopes is troublesome for young-earth creationists because the techniques have provided overwhelming evidence of the antiquity of the earth and life. Thus, the only real unknown is the composition of the core. I think what you are missing is the chemistry involved. Mechanism of uranium crystallization and falling through the magma We now consider in more detail the process of fractionation that can cause uranium to be depleted at the top of magma chambers. It turns out to be a straight line with a slope of
This would be very interesting, and would cause geologists to have to re-write many books, but the general story of geology would stand. This is because geologists do not believe Earth is billions of years old because of radiometric dating. Radiometric tools merely give us firm pegs to hang our signs on for the various eras, periods, and epochs of Earth history. Thanks for your comment, Kevin.
I would have to disagree with your suggested change in wording, however. While most definitely not all geochronologists do understand that there are false isochrons, that is never the way it is presented to students or the general public. This is unfortunate, of course, but it seems to be the norm when propaganda replaces science. I think what you are missing is the chemistry involved.
When we are dealing with trace elements not substances that are part of the crystal lattice , differential diffusion can have a significant effect. It is also not clear that there would be a general trend like you suggest.
Diffusion also depends on chemical issues. When you are dealing with different elements, you are dealing with completely different diffusion scenarios. Hayes discussing uranium-series dating. Since concordia diagrams also involve isotope ratios, however, I suspect that this problem exists there as well. In fact, they might even be the majority. I have no doubt that those who want to believe in an old earth will be able figure out a way to keep the overall story of geology the same, regardless of how important this effect turns out to be, if that can even be determined to any reasonable precision.
Yes, there are other issues at play as is the case with any over-arching scientific idea , but to her, radiometric dating is the most important reason she believes in an old earth. I have no idea whether she is the norm or the exception, but she does exist.
I was wondering how diffusion made any sense…. When I started my journey from old earth-evolutionism, it was much easier to see the flaws in evolutionary theory than those in the old age model. Thanks for your personal story, SJ.