Sunday, 22 December 2013

Chapter 11: Dendochronology

On pages 196-8 Sarfati discusses tree-ring dating (dendrochronology).  As noted in my overall review of The Greatest Hoax on Earth, Sarfati bases his discussion on an article published by his colleague, Don Batten, on the Creation Ministries International website.[footnote 1]

Batten's article is quite misleading.  For example, he compares the Bristlecone Pine (which is slow-growing, lives at high altitude, and is not known to produce multiple rings per growing season) with the markedly different Monterey Pine (which is fast-growing, has a natural environment that is coastal, and is known to produce multiple rings per growing season) to suggest the Bristlecone Pine could produce up to five growth rings per year.  Even other young-Earth creationist organisations disagree with this approach.  An article on the Answers in Genesis website admits that at present there is no good evidence that Bristlecone Pines can produce multiple rings per growing season.[2]

In my wanderings on the internet I came across a thorough critique of Batten's article:
Paul Smith, 'Dendrochronolgy Fact and Creationist Fraud' (14 Jan 2007) 
I have no idea who Paul Smith is (not that I'm in a position to pass judgement, given that I'm publishing anonymously as Washington Irving!) and I've had trouble accessing any kind of home page for the website.  Nevertheless, Smith's article is well worth a read as it clearly sets out the many problems with Batten's approach.

Here's a good non-technical summary from the end of Smith's article:
False rings, missing rings and other sources of error are relatively rare and random in the growth patterns of trees, even though some species have higher susceptibility than others. Dendrochronologists use the tree species with the fewest known sources of errors, and they work to eliminate all sources of errors. They cross-check the data with other species and other locations. If dendrochronology depended on one lone species, Dr. Batten might have an argument: it doesn't.
That all the different dendrochronologies correlate with each other also refutes Dr. Batten's implication of this being a problem that science somehow has not dealt with already. If Dr. Batten really is a scientist in this field ("As a tree physiologist"), then he is aware of - and used - the techniques used by scientists for identifying false rings. That he doesn't say anything about this speaks to his "honesty" again - his willingness to misrepresent the truth is evident.
It is curious that Dr. Batten wants to be seen as a scientist on this topic, but he doesn't include any information on his methodology or his results in the paper discussed.


[1] Don Batten, 'Tree ring dating (dendrochronology)' (undated) 

[2] John Woodmorappe, 'Biblical Chronology and the 8,000-Year-Long Bristlecone Pine Tree-Ring Chronology' (2009)

Wednesday, 11 December 2013

RATE (Radioisotopes and the Age of The Earth)

From 1997-2005, the Institute of Creation Research and the Creation Research Society ran a research project named RATE (Radioisotopes and the Age of The Earth).  RATE's work underpins many of the recent young-Earth creationist arguments against accepted dating methods for the age of the Earth.  RATE is cited is cited in several places by Sarfati (see his discussions of accelerated decay and carbon-14 on pages 189-192 and of helium in zircons on pages 214-5).

The key points of RATE's final report[footnote 1] can be summarised as:
  1. There is overwhelming evidence of more than 500 million years worth of radioactive decay.
  2. RATE's interpretation of the Bible and some scientific studies indicate a young Earth.
  3. Therefore, to reconcile the above points, radioactive decay must have been accelerated by approximately a factor of one billion during the first three days of creation and during the Flood.
  4. The concept of accelerated decay leads to two unresolved scientific problems, the heat problem and the radiation problem, though there is confidence that these will be solved in the future.
RATE's report identifies four separate pieces of scientific evidence for the acceleration of radioisotope decay: helium in zircon crystals, polonium halos in granites, isotope discordance, and the presence of Carbon-14 (C-14) in diamonds.

Helium diffusion in zircons

Zircon crystals contain high quantities of uranium, which produces helium during its decay process.  This helium should normally be able to escape the crystal more quickly than it would be produced by uranium decay.  RATE found high concentration of helium in zircons and argued these can only be explained by a young Earth and accelerated decay (if the Earth has existed for billions of years, the helium would have escaped).

RATE has been criticised over the purity of the zircon samples it used, for the method in which it took diffusion measurements and for problems in its calculations.  More importantly, geochronologists do not consider diffusion rates of helium in minerals a reliable dating measure when used in isolation, because the rates are known to be highly variable.[2]

Radiohalos in granites

Radiohalos are darkened spherical patterns in rocks, caused by alpha particles released during radioactive decay.  Looking at polonium halos, RATE argued that because polonium has a short half-life and granite is thought to be formed by a long period of cooling, the halos should have disappeared by the time the granite hardened.  Therefore the granite must be much younger and have cooled rapidly.  As uranium and polonium halos are relatively abundant, RATE concluded the granites must have formed during the Flood and there must have been highly accelerated decay rates.

As RATE's report highlights, there is not an agreed and proven scientific model of explanation for all aspects of polonium halos.  However, there are several likely theories, to do with the presence of uranium in the granite.[3]  RATE also acknowledges the dilemma they face by proposing accelerated decay, which produces extraordinary heat, and also proposing a rapid cooling rate to form the granite.

Isotope discordances

 RATE's report states that radioisotope dates for all the isotopes in a rock should always agree, and then provides a number of examples where this is not the case.  RATE then argues that all radiometric dates are untrustworthy and accelerated decay explains the discordance in dates.  However, RATE fails to explain why there are so many cases beyond their examples where there is good date concordance for different isotopes.[4]  While discordances occur and their cause is not always understood, these instances fail to invalidate the vast amount of concordance.

Trace amounts of C-14 in diamonds

RATE argues that the detection of trace amounts of C-14 in diamonds (dated as hundreds of millions of years old) supports their claim of a young Earth.  After 100,000 years there should be no C-14 left in a sample which has not been exposed to external sources of carbon.  Therefore the presence of approximately 0.1 percent of C-14 as a percentage of the total carbon indicates an age for these rocks of approximately 50,000 years.

The difficulty, however, is in assuring there is not, and never has been, another source of C-14 for that sample since it was originally formed from organic material.  There are many subtle sources of C-14 such as contamination, microbial action, and some nuclear interactions.  RATE's report states extraordinary care was taken in handling the samples but it is virtually impossible to eliminate such sources, which is why chronologists discount the reliability of C-14 dating if the concentration is below approximately 0.5 percent.  Coal and diamond samples that the RATE team collected and analysed show significant variation from sample to sample, suggesting contamination.

Additionally, were the C-14 dating on these samples valid, this is still a date ten times older than RATE's desired age of 5-6,000 years.  Thus RATE has to argue for a different concentration of C-14 to total carbon in the atmosphere before the Flood (500 times lower than it is today), which changed rapidly during the Flood due to accelerated radioactive decay.[4]

The problem of accelerated radioactive decay

RATE's report provides no direct evidence for accelerated decay but rather explores theoretically how such an increase in the decay rates might have occurred.  RATE theorises that if God had slightly weakened the coupling force that holds protons and neutrons of an atom together in the nucleus, it would have lead to a change in decay constants of many orders of magnitude.  RATE speculates that this coupling force took a different value in at least two time periods in the past: the first three days of the creation week and the year of the Flood.  At other times, it was the same as today.  Critics of such a theory point out that the coupling force is a fundamental constant of particle physics.

RATE's report acknowledges the two most serious problems with the theory of accelerated decay: heat and radiation.  Over the 4.5 billion year history of the Earth, radioactive decay has produced tremendous amounts of both.  RATE theorises that around 4 billion years of the decay occurred within the first three days of the creation week and the remaining 500 million years occurred during the year of the Flood.  The Flood acceleration alone would have released enough energy to heat the Earth to a temperature of more than 22,000° C (roughly four times the temperature of the surface of the Sun).  That amount of energy would have vaporised the Earth, including the geologic evidence RATE cites in support of acceleration (such as radiohalos and zircons).

To remove the heat and preserve the Earth, RATE proposes volumetric cooling: when God accelerated radioisotope decay he also expanded the size of the universe twenty-fold to dissipate the heat.  However, volumetric cooling only works for gases, not solids such as the Earth.  Furthermore, even if volumetric cooling were valid, it is uniform rather than selective (so in order to sufficiently cool radioactive material it would also freeze the Flood waters, and all life aboard the Ark would have died).

The other major problem with accelerated decay is radiation damage.  Noah and his passengers would have to survive a year in which radioactivity was one million times greater than it is today.  RATE's report admits no known solution exists.  The lethal effect of radiation appears to be the primary reason RATE concluded that most accelerated decay occurred during the first two days of creation, before life existed, and not during the Fall and Judgment.[5]


[1] Larry Vardiman, Andrew Snelling, and Eugene Chaffin (eds.), Radioisotopes and the Age of the Earth, Volume II, Waco: Institute for Creation Research (2005).

[2] See: Gary Loechelt, 'A response to the RATE team regarding helium diffusion in zircon' (2009); Kevin Henke, 'Dr Humphreys' young-Earth helium diffusion "dates": numerous fallacies based on bad assumptions and questionable data' (2005-2010)

[3] See: Glen Kuban, 'Unfounded creationist claims about polonium radiohalos' (2006-2012); Lorence Collins, 'Polonium halos and myrmekite in pegmatite and granite' (1997)

[4] See: Randy Isaac's review and reply in 'A dialogue about RATE', Perspectives on Science & Christian Faith, Vol 60, No 1 (2008), pp 35-39

[5] See: Isaac in footnote 4 and Matthew Rognstad, 'Creationism and accelerated decay' (2005); Greg Neyman, 'Creation science book review: Thousands...Not Billions' (2006)