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Friday, May 23, 2014

Andrew Snelling concedes, radiometric dating of meteorites is solid

Figure 18 from Snelling (2014), illustrating the frequency of isochron ages obtained from the Allende CV3 carbonaceous chondrite meteorite via six independent radioisotope systems (color coded, in legend). Note the strong peak at 4.56 Ga, the conventional age of our solar system and Earth.
After years of sorting through the results of radiometric dates, all placing the age of our Earth and Solar System at ~4.56 billion years, Andrew Snelling has essentially conceded that he cannot twist isochron ages of meteorites and bulk-Earth materials into supporting his already disproven conjectures regarding accelerated nuclear decay. If you're not familiar with this claim already, Andrew Snelling and colleagues in the RATE team have decided to brush away the overwhelming evidence of an old Earth from geochronology by suggesting that at several points in Earth's 6,000-year history, rates of nuclear decay increased by a million times or more, leaving us with the false impression that geological history spans millions to billions of years instead.

Despite the obvious scientific deficiencies behind Snelling's claim (namely, that accelerated nuclear decay would obliterate all life/water/atmosphere on Earth), we should give Snelling credit for being the master of ad hoc, deus ex machina explanations so intricate, that they are rarely found outside popular science fiction writing. But since Snelling presents his claims within the cosmic fabric of this reality, you should be shocked by the level of deception that Snelling employs through propagating his message, and the level of deception that he ascribes to God, who must have tinkered arbitrarily with natural laws like a skilled, cosmic hacker, laying a trap for inquisitive scientists that dare reconstruct Earth history through natural evidence or deviate from oversimplified readings of Genesis. Regarding accelerated nuclear decay, Snelling writes:

"...changes [to physical laws governing atomic binding forces] would thus have to have affected every atom making up the earth, and by logical extension every atom of the universe at the same time, because God appears to have created the physical laws governing the universe to operate consistently through time and space, though of course He Himself is not bound by those physical laws which He can change at any time anywhere or everywhere."

 For Snelling, the philosophical possibility that God can arbitrarily change characteristics of how the universe functions has become an axiomatic point of departure to explain why both scientists and biblical scholars must be wrong about history. Snelling (2014) further writes in his concluding remarks about why meteorites may represent the 'primordial' creation material:

"Faulkner (2013) pointed out that the Hebrew word ‘āśâ meaning “to do” and “to make” is used specifically of the creation of the astronomical bodies in Genesis 1:16, rather than the Hebrew word bārā’ meaning “to create” as used in Genesis 1:1 in reference to the creation of the universe generally... Therefore, it seems entirely possible to read Genesis 1:16 as saying God used already-existing “primordial material” which He had created out of nothing at the beginning of Day One of the Creation Week (Genesis 1:1) to then fashion it into the other planets, their satellites and the stars. Most meteorites are believed have been derived from asteroids via collisions between them breaking off fragments that then hurtled towards the earth. So to be consistent, if the asteroids were also made on Day Four from this Day One primordial material left over from the making of the planets and their satellites in the solar system, then this would imply the meteorites could represent samples of this same “primordial material.”"

The implication here is that the Genesis author chose his verbs (or received them divinely) as a function of the material origins of different parts of the cosmos, rather than something of interest to the original, Israelite audience. This line of reasoning imports a rigid—and entirely modern—distinction between the Hebrew verbs in a manner that is fine-tuned to address the concerns of a 21st-century American audience. Thus Snelling's ad hoc approach to scripture resides in a symbiotic relationship with his ad hoc approach to science, each gaining traction from the other. Snelling reads what he wants to read in scripture so that he may see what he wants to see in nature. In short, he has traded truth for certainty.


Snelling's summary of radiometric dates obtained from this particular meteorite is messy, to say the least, and illustrates well why he will never be published in an influential, peer-reviewed journal. A bulk of the Answers Research Journal article consists of unnecessary background information and tedious petrological descriptions of the meteorite samples. These sections are inconsequential to Snelling's main thesis, that despite the overwhelming consistency and precision of radiometric dates (all pointing to an age of 4.56 Ga), he still won't accept that this one meteorite, let alone the universe, is much older than 6,000 years.

To preclude the most parsimonious interpretation of the data, accepted universally by research geologists, Snelling attempts to argue that the 4.56-billion-year age of the meteorite merely reflects the geochemistry of the primordial creation material. Essentially, he claims that both meteorites and the planets were derived from this primordial creation material, which consisted of all elements and isotopes created by God on Day 1. Both parent (radioactive) and daughter (radiogenic) isotopes were incorporated into the new material, according to Snelling. Then, accelerated nuclear decay affected all atoms in the universe at several stages in Earth history (defined arbitrarily by Snelling and other creationists). As a result, both meteorites and the bulk Earth contain a common distribution of isotopes from the Uranium-Lead, Lead-Lead, Potassium-Argon, Rubidium-Strontium, Lutetium-Hafnium, and Samarium-Neodymium systems, yielding a common isochron age for both meteorites and the bulk Earth. Since these model ages do not account for isotopes/elements inherited from the primordial creation material, they are not true ages, so Snelling is free to maintain his 'biblical age' of 6,000 years as an axiomatic reference.

In case you didn't follow all of that (it took me several attempts), don't worry. You need only reference Occam's Razor to understand why Snelling's conjecture is and will remain ad hoc conjecture. It is predictive of nothing, and his starting assumption regarding the age of the universe guides his interpretation of the data. This approach stands in stark opposition to conventional geochronology, which makes precise predictions that are confirmed/disconfirmed by real data.

Snelling's conclusions are scientifically meaningless, because he cannot account for the fact that these six radiometric systems yield the same age, based on decay rates measured in the present. Despite his attempt to plead otherwise (see below), the age of meteorites and the bulk Earth are obtained through independently verifiable results.

Why should all six isotope systems yield the same age if it is not real? That is the pressing question, which Snelling cannot answer, so he glosses over it with filler descriptions of the samples and discussions of Hebrew verbs.

If we apply Snelling's model to explain the radiochemistry of meteorites, then we must assume that the primordial creation material from which God made the meteorites/planets contained just the right proportion of isotopes so that after x amount of accelerated nuclear decay, all systems appeared to have aged precisely 4.56 billion years. But this is not science, and it barely qualifies as pseudoscience (which at least has the appearance of being scientific). We need a new category to account for the level of deception employed by Andrew Snelling's latest 'research' report. Can you think of an appropriate term?

Why are there isotopes?

Assumed by Snelling and all other creationists is the notion that a recently created universe should contain a wide assortment of both stable and radioactive isotopes. But why? What exactly in the young-Earth creationist paradigm would predict the existence of isotopes at all? Isotopes are not necessary to maintain life, either of plants/animals or the solar system itself. On the contrary, radioactive isotopes produce destructive heat and energy, which is the single most prominent cause of cancer, among other disorders.

In conventional science, the existence and relative abundances of isotopes are readily predicted by models of solar evolution, because stars produce elements with varying numbers of protons and neutrons by combining lighter elements of varying masses. It makes sense within this paradigm that isotopes exist in the first place, and by using isotopes as tracers for natural processes, we've made sense of the history of the universe. But I want to suggest that in the young-Earth creationist paradigm, the mere existence of isotopes (radioactive or stable) makes absolutely no sense. Did God make isotopes just to give scientists an additional tool by which to understand physical processes 6,000 years in the future? Any answer to this question by YECs will be entirely arbitrary, rendering Snelling's model of meteorite isotope systematics even more absurd.

Meteorite isochron ages using the Al-Mg, Hf-W, Mn-Cr, and I-Xe systems

Snelling makes an odd statement amid his discussion regarding the calibration of isochron ages to the Pb-Pb system (forgive the long citation):

"The other “successful” radioisotope methods are not really independent and thus objective, because they are calibrated against the Pb-Pb method (see table 1) and therefore are automatically guaranteed to give ages identical to those obtained by the Pb-Pb isochron method. Specifically, the Al-Mg method is calibrated against the Pb-Pb isochron age for the D’Orbigny achondrite meteorite (Bouvier, Vervoort, and Patchett 2008), the Hf-W method is calibrated against the Pb-Pb isochron age for the St. Marguerite chondrite meteorite (Kleine et al. 2005) and the D’Orbigny achondrite meteorite (Burkhardt et al. 2008), the Mn-Cr method is calibrated against the Pb-Pb isochron age for the St. Marguerite chondrite meteorite (Trinquier et al. 2008), and the D’Orbigny and LEW 86010 achondrite meteorites (Yin et al. 2009), and the I-Xe method is calibrated against the I-Xe age of the Shallowater achondrite meteorite (Hohenberg et al. 2001), which is calibrated against the Pb-Pb isochron age for the St. Marguerite chondrite meteorite (Brazzle et al. 1999). Thus, as to be expected, all the dates obtained by these methods which are calibrated against these Pb-Pb isochron ages all plot in the 4.56–4.57 Ga mode with the clustered Pb-Pb dates (figs 18 and 20)."

Note that missing from the list of supposedly 'calibrated' radioisotope systems are the ones I cited in the previous section to confirm that meteorite ages are independently verifiable (U-Pb, Sm-Nd, Rb-Sr, Lu-Hf, and K-Ar/Ar-Ar). The reason is that Andrew Snelling has misunderstood the application of short-lived isotope systems, such as the Al-Mg chronometer. Al-Mg chronometry cannot give you an age of 4.56 billion years, because it depends on a short lived isotope set (i.e. radioactive isotopes that decay very rapidly, and have disappeared since the early days of the solar system). Instead, Al-Mg isotopes tell us about how long it took for the cores of chrondritic meteorites (and their various minerals) to solidify after the accumulation of raw material. Of course, the Al-Mg ages must use the formation age of the meteorite, based on Pb-Pb isochrons, as their 'starting point'. Therefore, Snelling's claim that these systems are somehow calibrated to the Pb-Pb system to yield artificially consistent results is not only bogus, but completely ignorant of the basic science behind these various applications in geochronology.

Snelling showcases his stellar research in Table 1, which reports, for example, that some of the meteorite ages in his histogram were calculated through an Al-Mg isochron. He cites one paper by Bouvier et al. (2008), where he claims that Al-Mg isochron ages were calibrated to Pb-Pb ages. However, not only does the reference cited provide no isochron ages of any kind, it also makes absolutely no mention of the Al-Mg system, period.

Exhortation

Rather than wade through Snelling's repeated attempts to rationalize the success of geochronology in constraining the age of our solar system and geological history, I strongly encourage readers to recognize that Snelling has now subtly conceded the conclusion already reached by tens of thousands of his colleagues: we can pin down the age of the Earth with great precision, and it's far older than 6,000 years. Snelling's persistent trail of misguided arguments has long lead enthusiastic readers off the path of logic and evidence, perhaps to the point that these attributes of science are no longer recognizable. For this, I cannot help but to lament the loss of millions to the dark forest where Snelling has built his pseudoscientific palace. In case the loss is only temporary, however, I will continue to toss morsels of evidence from the lonely path.

3 comments:

  1. You know, its amazing how ignorant Dr Snelling is ignorant of the basic principles of geochronology. Take his analysis of Diabase Sill:

    https://answersingenesis.org/geology/grand-canyon-facts/radioisotopes-bass-rapids-grand-canyon-arizona/

    He cites "discordant isochron" dates as evidence of inaccuracy. What he completely omits is how many of his data points fall so far from the isochron line, indicating how horribly contaminated the samples were (with the exception of the Rb-Sr isochron) Im surprised he didnt outright discard the results. Even a rank amateur like me instantly saw what was wrong. Tragically, he has basically discarded everything he has learnt and is wholly focused on undermining the validity of the scientific method. Really.....

    By the way, I noticed that some of the readings from the other dating methods fell in the 5.0Ga and 3.5Ga range. I wonder why?

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  2. Sorry should have typed "You know, its amazing how ignorant Dr Snelling is of the basic principles of geochronology." haha

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