14C dating—who is fooling whom?
Published: 8 December 2018 (GMT+10)
Bill N. of Australia wrote in response to the article How old? When archaeology conflicts with the Bible, saying that 14C, dendrochronology, and uranium-thorium (U-Th) dating techniques are indeed trustworthy, as are the experts and labs that perform these tests. He asks, “What did CMI do to disillusion them, and who is fooling who?” His message is below in red. Responses from CMI’s Gavin Cox (and some from Robert Carter on corals) are interspersed:
There are several tree-ring chronologies which are reported to agree with each other, and C14 dating of rings enables a calibration curve for C14 against age to be constructed to account for variation of C14 production from time to time due to altered solar activity or volcanism.
Thanks for your question Bill; it is very involved and has multiple lines of reasoning within it. If you follow the link in footnote 25 from my article you will see a link to the Belfast tree ring correlations, so your statement, “There are several tree-ring chronologies which are reported to agree with each other” is already answered. Obviously I am questioning the conclusions of that study. First, just because several things agree does not make what they agree upon correct or true (i.e., ‘correlation does not prove causation’). Second, while agreement on an outcome among several independent techniques is generally considered a good indication of a reasonably reliable outcome, all tree-ring chronologies are derived using the same basic assumptions, so they can hardly be considered to be independent determinations. Thus, the fact of their agreement is not necessarily a compelling argument for the correctness of the result.
That being said, the Belfast data is a well-known example of a lengthy, (claimed) continuous tree ring chronology, from AD 5 – 2006, but this particular example (methodological assumptions aside) is obviously not a problem for the biblical time-scale.
I also mention supposed agreement for bristlecone pine (BCP) tree rings in my article, but that depends on matching rings from living and dead trees (“prone wood”) that has been 14C dated to multiple thousands of years. This is highly subjective and goes against common sense, in that the wood should have rotted or disintegrated in all that supposed time. For example, one study published by “a group of researchers from the U.S. Forest Service and the University of Minnesota” concludes fallen conifers will take 57 to 124 years to completely disintegrate,1 while another article reports tree stumps generally take approximately 10 years to disintegrate.2 This, of course, depends on the exact environmental conditions, but fallen trees generally do not last for centuries, let alone millennia.
Tree ring dating also assumes a single annual growth ring, but this assumption has been demonstrated to be false, in that BCPs have been shown to develop multiple annual rings when under harsher, more arid conditions. My article quoted a secular expert in dendrochronology, Dr. Grissino-Mayer, who openly raised major questions regarding the reliability of dendrochronology at the 2015 Association of American Geographers annual meeting in Chicago. So your implication that 14C and dendrochronology are ‘wholly reliable’ methods is not shared by the experts in those fields.
These methods are highly subjective, and rely upon a rigid adherence to uniformitarian principles. I also question the idea that 14C calibration can take account of ‘altered solar activity’ as you put it. If these changes in the past have not been observed, then they cannot be accurately quantified and so the models cannot take such changes into account. See the Creation Answers Book, chapter 4 (pp. 68–70), on this subject (available here). The same would be true for volcanism. If the investigator was not there to observe and measure the extra 14C-free volcanogenic carbon dioxide absorbed into the tree, then how can accurate models be calibrated to take this into account? Fellow biblical creationist John Woodmorappe states:
“Artificially-inflated 14C dates have been found to occur when trees absorb ‘infinitely old’ carbon dioxide released into the atmosphere from local, volcanogenic, subterranean sources. This is not to be confused with wood contamination because the carbon is firmly locked within the wood fibres. A similar effect has long been recognised with the fictitious ‘built-in’ carbon-14 dates that occur in molluscs when they absorb ‘infinitely old’ carbon from carbonate rocks. In addition, creationists recognise that the global atmospheric build-up of 14C after the Creation and Flood would have produced artificially-old carbon-14 dates. However, the widespread emanation of 14C-free volcanogenic carbon dioxide after the Flood would have further inflated the carbon-14 dates of tree rings in a systematic manner in many parts of the world.” (full article here)
Corals can be dated using U-Th and C14 on the same sample and this produces the same curve. U-Th dates are not affected by solar activity and so that can check C14 dates. Cores of lake beds such as Lake Malawi and Lynch's Crater show a linear increase in C14 age with depth as would be expected.
Your point is about the absorption by corals of soluble 14C, uranium and thorium (from sea water, and or underlying rock). CMI’s Robert Carter has a PhD in marine biology and happens to be an expert in the ecology of corals. He doubts that two different methods would produce the ‘same curve’ on a sample for the following reasons:
- Uranium is highly soluble in seawater. Thorium is not. (The ratio 232Th/238U in seawater approximates 1x10-5).
- Corals readily absorb ambient U and Th from seawater. The amount of each incorporated in the skeleton generally reflects the solubility difference.
- How can you age-date something using the 230Th/234U method when the amount of 230Th in recent corals is highly variable? Seawater is not the only source of thorium, and different sources have a different 230Th/232Th ratio. The ratio in carbonates (1x10-2) > deep seawater > surface seawater > atmospheric dust (4x10-6). In young corals, ratios can be between 0 and 2x10-5.
- 230Th ranges from 0 to 1000 pg/g in modern corals,3 and one can measure different amounts of 232Th from corals of the same age.
- Thus, the amount of 230Th in corals is a combination of environmental and radiogenic (from interstitial U decay) sources.
- Finally, and this is the crux of the argument, one cannot measure 230Th/234U in ancient coral skeletons without making a lot of assumptions about the starting quantity of both constituents. This is affected by water temperature, nearby sources of both uranium and thorium (e.g. volcanic islands), and incoming thorium (of both isotopes) from various distant sources. The final age is model-dependent, after accounting for multiple correction factors.
Dr Carter says:
“I highly suspect there are funny things happening with 12C and 14C in coral skeletons as well, but that is another study for another day. Regarding 14C dating of lake sediments, of course there is a correlation of age vs. depth. That is expected by all sides. But we expect there to be an anomalous increase with depth because 14C in the atmosphere is increasing over time. Not only are we not in equilibrium since Creation, but the magnetic field of the earth is continually declining. So any deep lake sediments that were laid down in the early post-Flood centuries will appear to be older than they really are. Regarding oxygen isotope measurements in corals, yes, this is temperature dependent, but it is also highly tied to circular arguments about climate change (Milankovitch Cycles), etc. You can't really age-date a coral skeleton based on oxygen isotope ratios without already knowing where it is in relation to already-dated corals, for different dates can yield the same ratio. So, they string together many ratios from the same coral at different depths and correlate these to the results of other corals. This is directly parallel to dendrochronology.
Conclusions: The sceptics sound like they have everything tied together in a neat little bundle, with multiple independent correlating measurements. But, how much of this is due to them rejecting any method that did not already give them what they want? And how much of this is due to one or more of the primary methods being based on wrong assumptions and so the following methods only appear to correlate?”4
Like I said in my article, unless the investigator was there to measure and observe the inputs and outputs for the history of the sample being tested (whether for 14C or 234U–230Th), it will never be known for certain what the initial conditions were, nor how environmental factors have changed the ratios of parent-daughter isotopes. Therefore, all claims of accurate clocks going back into the unobserved past must be met with scepticism.
Unless the investigator was there to observe and measure all variables, it can never be known for certain that the final observed and measured ratios of a sample under investigation reflect a simple linear relationship going back into deep time. Worse, there are good reasons to reject uniformitarian assumptions. Factors like the decrease in the Earth’s magnetic field, changes in solar activity received by the earth, radical changes to the 12C/14C ratio after the end of the Ice Age, modern factors including the Industrial age, atomic testing, and the all-important Flood, have impacted the ratio in ways for which we cannot fully account.
There are over 100 C14 labs doing a total of 10s of thousands at least of tests annually. If C14 is so unreliable, why haven't researchers who send their specimens for testing noticed it? What does CMI do to disillusion them?
But, contrary to your comment, researchers have actually noticed anomalous results for their samples for decades, and CMI has simply reported on their results. There was a major study of 14C reported by the RATE team (Radioisotopes and the Age of the Earth) back in 2005. They listed 90 peer-reviewed papers, going back to 1984, that reported anomalous results for 14C in samples supposedly 100,000 to multi-million-years (in the evolutionary time-scale). Of course, this is an impossible situation, unless these ancient materials are young—which we believe they are. One of the researchers who carried out this study (Dr. John Baumgardner, who holds a PhD in geophysics and space physics and was a career researcher at Los Alamos National Laboratory) stated:
“A remarkable discovery made over the past twenty-five years is that organic samples from every level in the Phanerozoic portion [life-bearing] of the geological record, when tested by highly sensitive accelerator mass spectrometer (AMS) methods, display significant and reproducible amounts of 14C. Because the lifetime of 14C is so brief, these AMS measurements pose an obvious challenge to the standard geological timescale that assigns millions to hundreds of millions of years to this part of the rock record…”5 (article pdf available here).
Official calibration curves for C14 have been produced for many years to account for variation in C14 production. If these are not based on good evidence, who is fooling whom?
Unless the experimenter is claiming to be omniscient, then the further one goes back in time the more unreliable the dates obtained will be. The Hallstat Disaster/Plateau graph discussed in my article is a known example of this, and no amount of calibration can yield accurate dates in the period 400 – 800 BC. And yes, it’s an “official calibration curve”, as you put it, that does exactly the opposite of what you claim, showing for all to see an area of unresolvable inaccuracy.
A critical factor to consider, that, in my mind, blows most of the claims of accurate 14C dating for very old samples out of the water: Willard Libby, the Nobel Prize winner who invented the 14C method, assumed an equilibrium condition between the production of 14C and its disintegration. It was a critical assumption. Subsequently, scientists have found that the system (Earth and atmosphere) has not yet reached a steady state, which means the Earth cannot be more than a few thousand-years old, because it only takes about 30,000 years to reach equilibrium based on the half-life of 14C.
Finally, you ask “who is fooling whom?” I would ask, is it the method itself, or the assumption behind the method that is fooling everyone? I strongly suggest it is the unprovable assumption of uniformitarianism that is fooling everyone. It is worth re-reading Dr. Grissino-Mayer’s five concluding remarks at the end of my article as an example of a secular expert in his field saying exactly this. And the same things have been pointed out by creationists for years (regarding the faulty philosophical assumptions behind the methods). Hutton defined what uniformitarianism is and explained how he applied it to earth history. He wrote:
“The past history of our globe must be explained by what can be seen to be happening now. … No powers are to be employed that are not natural to the globe …”.
Hutton did not derive his assumptions from the geological evidence, he was, rather, imposing unprovable constraints on these observations, determining what explanations would be allowed! Moreover, he was doing it in such a way as to preclude Noah’s Flood as an explanation, no matter how well such an explanation might explain the observations, simply because, (i) we do not see global floods happening now and, (ii) it was a supranatural phenomenon. Uniformitarianism, a-priori, rules-out a supernatural creation, or a global Flood. It is these assumptions that are fooling everyone. It reminds me of this relevant passage of Scripture that seems to prophecy the kind of uniformitarian thinking that leads so many astray:
“They will say, ‘Where is the promise of his coming? For ever since the fathers fell asleep, all things are continuing as they were from the beginning of creation.’ For they deliberately overlook this fact, that the heavens existed long ago, and the earth was formed out of water and through water by the word of God, and that by means of these the world that then existed was deluged with water and perished. But by the same word the heavens and earth that now exist are stored up for fire, being kept until the day of judgment and destruction of the ungodly”—(2 Peter 3:4–7).
Please don’t be fooled into thinking things will ‘continue as they always have’ as per the self-serving uniformitarian assumptions. There was a global Flood in the past and Christ will return to judge the world in the future, this time by fire, I trust you will be ready for His return.
References and notes
- Heisman, R., When a tree falls in a forest, northernwoodlands.org, 20 January 2016; accessed 28 November 2018. Return to text.
- How long does it take tree stumps to rot? https://homeguides.sfgate.com/long-tree-stumps-rot-84943.html; accessed 28 November 2018. Return to text.
- Pg stands for picogram, or 0.000 000 000 001 g. Return to text.
- shadow.eas.gatech.edu/~kcobb/cobb03.pdf Return to text.
- (John R. Baumgardner “14C Evidence for a Recent Global Flood and a Young Earth” (587) pp. 587-630 in RATE II: Radioisotopes and the Age of The Earth: Results of a Young-Earth Creationist Research Initiative, (Volume II), L. Vardiman et al., eds. (San Diego, CA: Institute for Creation Research and the Creation Research Society, 2005) Return to text.