Paul Giem: Isochron Dating Rocks and Magma Mixing

There seems to be agreement about this, at least if we look at only in isochron at a time and ignore conciliatory evidence that would not be explained by mixing.

This I’m not convinced by, but I have NOT looked closely yet.

[late edit: forgot the NOT]

I’m not sure why that’s important if every one grants the first point you made.

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It’s important because if mixing lines don’t have matching “isochron ages”, then you can test the mutual validity of isochrons by seeing if they report the same ages.

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Swamidass (C21), I’m glad we have agreement of the first question, and I fully understand and agree with your caveat.

For the second question, I would appreciate it if you did look closely at it. :slightly_smiling_face:

You seem to have skipped the third question, and in my opinion it is a very important one. Can we really believe that strontium isotopes homogenize across meters to kilometers of magma? The existence of undoubted mixing lines in magmas suggests that thorough homogenization of strontium isotopes is at least not mandatory.

Finally, I agree with John_Harshmann (C22) regarding the importance of question four. His answer (“if mixing lines don’t have matching “isochron ages”, then you can test the mutual validity of isochrons by seeing if they report the same ages”) could be completed; if one does get matching “isochron ages” from a mixing line, one cannot use matching isochron ages to prove that the isochron ages are real. One then needs other criteria.

Of course, one must always qualify any such generalizations based on the data. In a given test, we can prove some proposition for a given magma or set of magmas, but although it may be a reasonable first assumption, the assumption that a given test proves some concept for all magma types is still an assumption, and should be rechecked for other magma types before we simply use it uncritically.

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Remembered this elucidating conversation from a while ago. @PaulGiem, thanks for bringing this to our attention, and sorry for the delayed response.


Can you clarify the questions you are asking about? I don’t know which questions each number refers too, and you’ve been a patient interlocure. I want to be sure I answer fairly and on point.

I don’t think isochron dating requires homogeneity at all scales, does it? Rather, by other means, a well mixed geological formation (which might be large or small) that would have cooled at the same time are identified. It is only from that context that it is valid to compute an isochron.

The issue of a two-component mixture may be a confounder that can’t be ruled out merely because the samples fall in a line. However, it seems that in many cases we have multiple different isotopes producing the same age for the same set of samples (Isn’t that right?).

Also, if isochrons lines were common confounded substantially by mixing lines, we would see wildly contradictory dates by isochron dating very frequently. Moreover, it would have been impossible to validate the isochron dating in the first place; any cross checks with independent dating methods would usually be totally off. As I understand it, isochron dating is usually not wildly out of line with other dating methods, and has been validated. It generally gives a concordant date, with far more precision.

For this reasons, I have a hard time believing (without some evidence to the contrary) that isochron dating is, generally speaking, not to be trusted due to this confounder.

@PaulGiem, wouldn’t it require fine tuning of the two component mixtures to get the SAME date predicted from DIFFERENT isochrons across the SAME set of samples? Likewise, if the isochron dates matched dates by other non-isochron methods, wouldn’t the composition of the two components have to be fine tuned?

(If you disagree, can you produce any math that shows that mixing lines would produce the same date independent of decay rate and starting composition? I don’t think that’s the case.)

If that is the case, and I’m not missing something, the general concordance of multiple isochrons would seem to be strong argument for validity. If data showed that multiple isochrons were usually concordant if they satisfied other external checks, perhaps that should be enough to neglect the cross check in most cases.

I’m curious @davidson’s thoughts and others with expertise here. It’s been a while since we engaged this conversation, so it is possible I lost an important thread.

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Sawmidass (C24),

Thanks for letting me know of your reply by e-mail. Otherwise I would have missed your reply.

You quote me and say,

For the second question, I would appreciate it if you did look closely at it. :slightly_smiling_face:
Can you clarify the questions you are asking about? I don’t know which questions each number refers too, and you’ve been a patient interlocure. I want to be sure I answer fairly and on point.
The numbering of the questions came from my C20, paragraph 2, where there were 4 major questions I raised. The second question was,
Is there something identifiably wrong with the assumptions or the math of my proposed explanation for how multiple “isochron lines” can be flattened to roughly the same degree?
I hope that clarifies the question involved. You may want to do a careful read of my paper that was originally referenced ( https://scientifictheology.us/wp-content/uploads/2020/12/IsochronDating.pdf ). It is free on the internet.

On question 3 you comment,

I don’t think isochron dating requires homogeneity at *all* scales, does it? Rather, by *other* means, a well mixed geological formation (which might be large or small) that would have cooled at the same time are identified. It is only from that context that it is valid to compute an isochron.
It appears that you do not really understand the assumptions that are required to be fulfilled for a valid isochron date. I will try to explain the fundamentals of isochron dating, so that you can see those assumptions for yourself.

The general principles of radiometric dating are that one measures parent isotope (P), daughter isotope (D), and (usually someone else measures) the decay constant k (lambda is usually used but I’m too lazy to figure out how to put in Greek letters). If one allows Po (my imitation of P subscript 0) to represent the amount of P at time zero, the general formula is,

P = Po exp(-kt) = (P + D) exp(-kt),

or with some rearrangement,

t = ln((P + D) / P) / k

(these are standard formulas).

In some systems, say, potassium-argon dating, it is assumed that the daughter argon all is driven off when the rock is heated (time To), and so the D is simply the measured Ar-40, and the potassium is simply the measured K-40. (Actually one has to correct for the branching ratio, and for absorption of argon from the air, and the total potassium is measured rather than the K-40, and the assumption that all the argon is driven off may not be accurate, but let’s not open that can of worms.) But for several systems, including rubidium-strontium dating, samarium-neodymium dating, and uranium-lead dating (two different kinds–U-238-Pb-204 and U-235-Pb-207), it simply is not believable that the daughter element is all lost at time To, and so one must figure out another way to account for residual daughter element in the original melt (magma, lava, whatever) that would otherwise throw off our calculations.

So what is done is the assumption is made that, for example, in rubidium-strontium dating, the strontium isotopes are homogenized throughout the melt, to incredible accuracy (the ratio of Sr-87 to Sr-86 when measured might vary, say, between 0.690 and 0.760 for an older rock, with the baseline needing to be flattened to ~1 part in 100 to ~1 part in 1000 in order to give a reliable isochron line–see the original line, labeled t0, on the illustration at the top of this page, that is completely horizontal). If one does not have an initially constant ratio of Sr-87 to Sr-86, one cannot get an accurate age.

You say (C24),

I don’t think isochron dating requires homogeneity at *all* scales, does it?
Technically it only requires homogeneity at all *measured* scales. There is no substitute for homogeneity (however it happens) if one wants an accurate date.

This is not just my opinion. Mebus A. Geyh and Helmut Schleicher, authors of Absolute Dating Methods (Berlin: Springer-Verlag, 1990), say on pages 12-13,

For example, there are indications that the condition of isotopic homogeniety of a magmatic body at time t0, prerequisite for isochron dating of magmatic rock, is not always fulfilled. But for the Rb/Sr system, for example, initial heterogeniety would place the determination of a whole-rock isochron age in doubt, if not make it impossible.

You say,

The issue of a two-component mixture may be a confounder that can’t be ruled out merely because the samples fall in a line. However, it seems that in many cases we have multiple different isotopes producing the same age for the same set of samples (Isn’t that right?).
I do know that in some cases the dates are close enough to be statistically indistinguishable. What I do not know is what proportion of dates fulfill those requirements. I know of several examples where the dates are not close to each other, and even some where concordant dates are generally rejected as erroneous. I can share this evidence if you wish, but this is, of course, anecdotal evidence. What I would like to see is a study where the tests are done "blindly" and all the results are published, sort of like what one would do in a good study in medicine.

You say,

As I understand it, isochron dating is usually not wildly out of line with other dating methods, and has been validated. It generally gives a concordant date, with far more precision.
I am not quite as confident as you, and would love to see the data behind your understanding.

You say,

@PaulGiem, wouldn’t it require fine tuning of the two component mixtures to get the SAME date predicted from DIFFERENT isochrons across the SAME set of samples? Likewise, if the isochron dates matched dates by other non-isochron methods, wouldn’t the composition of the two components have to be fine tuned?
One of the points of the paper I originally wrote was precisely to ask what kind of fine tuning it would take to get different isochron dates to match if the isochron dates were really produced by mixing lines. You, or perhaps one of your friends, might read the paper and critique it carefully but fairly, and could do all of us a favor.

You say,

(If you disagree, can you produce any math that shows that mixing lines would produce the same date independent of decay rate and starting composition? I don’t think that’s the case.)
That's precisely what I was doing in the paper. I was offering what I believed were testable hypotheses, and was hoping someone with the requisite expertise (and funds) could test them. If everyone waits long enough, I may test them myself.

I appreciate your comments, and look forward to further comments.

As @John_Harshman mentioned earlier, you would also have to explain how Rb/Sr isochron dates also match the ages as determined by other decay series, such as U/Pb and K/Ar. Dalrymple wrote a great assay on the subject:

What is the mechanism by which strontium isotope partitioning can result in an Rb/Sr isochron date that just happens to match the K/Ar dating of a tektite thousands of miles away when we look at the same geologic layer?

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A useful statistical approach is to look at the sources of error and quantify them in a Variance Components Analysis. This allows each source of error to be expressed of a percentage the total statistical variance, and it is often applied to reliability studies - and reliability is the basic question at hand here.

My rough understanding is that radiometric dating methods have a total measurement error of about 10%. Some errors will be greater of course, and others smaller, but the majority of estimates should be correct to within ~10% of the actual age.

Rather than saying a measurement is wrong, it would be helpful to quantify just how wrong it is. We need to know if it is accurate enough to be useful, and if it systematically biased to be younger or older than it should be.

I tried to look up the book you cited, did you mean this one?

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T_aquaticus (C26),

You state,

... you would also have to explain how Rb/Sr isochron dates also match the ages as determined by other decay series, such as U/Pb and K/Ar.
You seem to miss the fact that U/Pb dating is (or more properly both U/Pb dating methods are) also an isochron method, and also that according to the article, Ar/Ar dating (a variant of K/Ar dating and often used in Dalrymple's examples) is also sometimes explicitly an isochron method, as the Dalrymple essay itself notes:
The 40Ar/39Ar isochron method used by the Berkeley scientists, however, does not require any assumptions about the composition of the argon trapped in the rock when it formed — it may be atmospheric or any other composition for that matter.
A major point of my original article was to try to find the conditions that would be required for "isochron" lines to match dates without their actually being related to age. I may or may not be accurate, and the conditions I found may or may not be representative of the real world, or at least that part of it where "isochron" ages match each other, but a good critique must understand the theory.

The essay you cited by Dalrymple makes perhaps the best case for the reliability of radiometric dating. The examples he gives are impressive.

I do have some concerns. Having read some papers by Dalrymple in the professional literature, I can attest that there he is a careful writer. However, in his The Age of the Earth (Stanford: Stanford University Press, 1991), written to counter creationists, he appears to be less careful. On p. 120 he states that the isochron method is “self-checking”. Given our discussion above noting that mixing lines can precisely mimic isochron lines, this is at least an overstatement.

In the essay you referenced, also against creationists, some statements can also be misleading. In the second paragraph he states,

If the earth were only 6000–10 000 years old, then surely there should be some scientific evidence to confirm that hypothesis; yet the creationists have produced not a shred of it so far.
If one wanted to qualify this statement by saying that creationists had very little evidence for a short age of the earth, as opposed to the phanerozoic, one could probably get by with it. And if one insisted on radiometric evidence, as implied in the next sentence, I think he is mostly correct (with the possible exception of C-14 dating). But this does gloss over such things as finding soft tissue in dinosaur bones.

This gets into an annoying habit that some on both (all three? all 20?) sides of the argument can have. Rather than state that the evidence taken as a whole supports their position, they state that the opposition does not have a shred of evidence to support their position. Given the incompleteness, and sometimes inaccuracy, of our knowledge, that would seem to be a statement better suited to a faith-based position than to a scientific one.

Dalrymple (or whoever posted the paper to the internet) also rather inexplicably left out the references to his essay. The citations are there, but no references at the bottom. Some of the references, such as (Dalrymple 1969), I have already read, but finding the others is challenging given the available information.

His examples include a meteorite impact in the Cretaceous, the K-T boundary, the age of meteorites, and the Mt. Vesuvius eruption. The last is recent, and the third is before the origin of life on earth, and therefore they are not of as much interest, at least to me, as the other two. The Cretaceous and K-T boundary events would be much more persuasive if I could be assured that the dates were done blindly (standard protocol for medicine, but not for geological research), and all the results were reported, as I have seen other datasets where selective reporting can be documented.

Dan_Eastwood (C27)

Thank you for your response. Yes, that is the book, or rather, a reprint of it.

The question I am raising is not of reproducibility (the question of precision), but systematic error possibly introducing bias (the question of accuracy). You seem to recognize this when you say,

We need to know if it is accurate enough to be useful, and if it systematically biased to be younger or older than it should be.
Thus, simply expanding the error range from ~1% to ~10% may not be a helpful procedure in deciding our question. That only affects precision. Rather, carefully designed experiments to tease out, or rule out, the possible sources of systematic error would be helpful. Actually, the Ar/Ar experiments on the Vesuvius eruption are a helpful test, as are other tests on recent material, especially blinded ones as far as the labs are concerned.

The evidence as a whole supports our position.

The issue that you are eliding is that our side PRODUCES virtually all of the relevant evidence, while your side produces virtually all rhetoric.

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That’s a different issue and off topic. I certainly agree, and it is an important framing point, but I don’t see need to belabor it.

The focus here is thinking specifically about isochrons.

I agree. Whatever we think the evidence on balance shows, it is a fundamental scientific concern to understand the import of each line of evidence on its own.

That would be interesting, though full blinding may not be needed.

U/Pb dating of zircons is not an isochron method, as far as I am aware, and neither is K/Ar dating.

However, that really doesn’t matter. You would still need to explain how Sr isotope partitioning could coordinate itself with U isotope partitioning so that rocks from the same geologic layer would produce the same dates. On top of that, you would also need to explain how all of these different methods produce dates that correlate with fossils. For example, why don’t we find non-avian dinosaur fossils above rocks that date to 65 million years before present? How is Sr partitioning able to change in response to the fossils around it?

Creationists have not demonstrated that the tissues found in dinosaur bones could not survive for 65 million years. They simply assert that they can’t survive that long without a shred of evidence to support the assertion.

What is stopping creationists from going to those same rocks and doing their own measurements? Accusing scientists of fudging their data is a very, very serious accusation, and it shouldn’t be done in an off-hand manner. If creationists really had the convictions in their own beliefs then they would be exposing falsified data, but they aren’t. Why? Because deep down I think they know the data is right.

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I sent a note just now to a couple scientists with expertise in this area. Perhaps one or more of them can enlighten us.

I feel like I may be missing something basic in this thread. Is that not what crystallization does at time zero, reject daughter elements at the time of crystal formation? The same consideration applies to degassing of magma.

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speaking as a non-expert . . .

Yes and no. Depends on the mineral.

Zircons exclude Pb really well, and you would only need to use the isochron method for the youngest rocks. Perhaps an expert could chime in on the industry standard for U/Pb methods.

Since there are two isotopes of U that decay to different isotopes of Pb, you can use each series to check the other which is called concordia/discordia dating.

The dates from each decay series should fall on the blue concordia line. As far as I am aware, this isn’t considered an isochron.

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Precision, yes, but it also puts a bound on inaccuracy. In statistical terms the measurement error (variance) is the sum of actual measurement variance plus the square of the bias. If the total error is ~10% then the bias shouldn’t be more than that.

You have a good point about careful experimentation though, because we need to recognise a systematic bias exists before it can be corrected. In some cases the means for such experiments exists naturally, such as separate dating from the U-235 and U-238 in zircon crystals.

This pretty much exhausts my knowledge of geochemistry, but I will hazard one further opinion: It seems highly unlikely that any strong systematic bias should exist across all dating methods, and that such an oversight could exist for long without someone noticing and improving on it. We see these sorts of refinements of method fairly often in physics and astronomy. I suspect we can practically rule out any large unknown bias, but I don’t know where to begin looking for evidence to support that (geochemical journals, perhaps??).

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Mercer (C29),

I respect the position you have taken, and agree that most of the evidence is produced by those adhering to a long chronology. Some short chronologists are trying to change that, which in my opinion is a good thing.

Swamidass (C30),

Thank you for bringing back the focus. And thank you for recognizing that the details of each particular argument, and even each particular datum, matter. It is tempting to allow the greater narrative to trump the details, but that way lies disaster. Just because the Germans were eventually going to lose WWII didn’t mean that Allied commanders could engage in poorly thought out tactics without consequences.

Swamidass (C31)

Full blinding of the laboratories should be done, for the same reason that full blinding in medical studies should be done. It removes the possibility of unconscious bias.

Part of the reason that I stipulate this is that I have seen a study published that, according to one of my friends who was an adherent of the standard chronology, became a classic, namely, Evernden JF, Savage DE, Curtis GH, James GT: “Potassium-argon dating and the Cenozoic mammalian chronology of North America.” Am J Sci 1964;22:145-98. The list of ~100 dates, all in order except for one pair, is impressive. However, note that many dates were not used. They discuss on pp. 171-4 why all but one potassium/argon date for the Rusinga Island biotites was discarded. But they continued to apparently uncritically use biotite dates in other areas where the dates obtained matched their expectations. In addition, they note on p. 174, “Unfortunately many of the samples that passed field inspection for suitability and were laboriously collected, later proved unsuitable for dating. . . . Thus, of some 65 samples collected by M. Skinner only 10 could be used.” It might have been interesting to know why such samples proved unsuitable for dating, and what their potassium/argon dates were.

Note that argon/argon dating has now largely supplanted potassium/argon dating, suggesting that potassium/argon dating was not optimal, as one might assume from the article by Everndon et al.

One might argue that the dates are generally in the same ballpark, and that should be good enough. But remember, the argument that is being made is that the dates from different dating methods match each other to within the limits of experimental error, and therefore must be measuring time. If they really don’t match each other, that argues against the general agreement being due to time, and in a fair evaluation, that fact (if true, of course) should not be omitted. Just do blind tests, like we send away blood samples for potassium or thyroid-stimulating hormone without telling the lab what results we expect.

T_aquaticus (C32),
You quote me and say,

PaulGiem: You seem to miss the fact that U/Pb dating is (or more properly both U/Pb dating methods are) also an isochron method, and also that according to the article, Ar/Ar dating (a variant of K/Ar dating and often used in Dalrymple’s examples) is also sometimes explicitly an isochron method, as the Dalrymple essay itself notes:
U/Pb dating of zircons is not an isochron method, as far as I am aware, and neither is K/Ar dating. However, that really doesn’t matter. You would still need to explain how Sr isotope partitioning could coordinate itself with U isotope partitioning so that rocks from the same geologic layer would produce the same dates. On top of that, you would also need to explain how all of these different methods produce dates that correlate with fossils. For example, why don’t we find non-avian dinosaur fossils above rocks that date to 65 million years before present? How is Sr partitioning able to change in response to the fossils around it?
You are right that sometimes U/Pb dating is sometimes used without constructing isochrons. However, when it is used without isochrons, it is known to be hard to reset, leading to inherited ages.

K/Ar dating has problems with inherited argon, which is why the Vesuvius eruption was dated with Ar/Ar dating rather than K/Ar dating, and partly why Ar/Ar dating has largely supplanted K/Ar dating (sample size is also a factor).

I’m not sure what U isotope partitioning has to do with the dates involved. It would be more likely to be the lead isotope partitioning. It would be going a little far afield, but there is a story about bird-like dinosaur tracks that is somewhat disturbing regarding both Ar/Ar dating and index fossil dating if you are interested.

You quote me and say,

PaulGiem: If one wanted to qualify this statement by saying that creationists had very little evidence for a short age of the earth, as opposed to the phanerozoic, one could probably get by with it. And if one insisted on radiometric evidence, as implied in the next sentence, I think he is mostly correct (with the possible exception of C-14 dating). But this does gloss over such things as finding soft tissue in dinosaur bones.
Creationists have not demonstrated that the tissues found in dinosaur bones could not survive for 65 million years. They simply assert that they can’t survive that long without a shred of evidence to support the assertion.
There is that “without a shred of evidence” again. If your memory is as long as mine, you may remember being taught that fossils were completely replaced by minerals because they were millions of years old. You may also remember that Mary Schweitzer’s work was hugely controversial because many geologists, and chemists, didn’t believe collagen and other proteins could last that long. You may also remember that she has tried experiments to find a mechanism for protein to last that long, which would not be necessary if it were obvious that they could without some kind of special process. I am not saying that some kind of unusual process won’t be found that will explain all of this from the perspective of the standard geological timescale, but those who see this phenomenon arguing for a shorter age aren’t just being stupid here.

You quote me and say:

PaulGiem: The Cretaceous and K-T boundary events would be much more persuasive if I could be assured that the dates were done blindly (standard protocol for medicine, but not for geological research), and all the results were reported, as I have seen other datasets where selective reporting can be documented.
What is stopping creationists from going to those same rocks and doing their own measurements? Accusing scientists of fudging their data is a very, very serious accusation, and it shouldn’t be done in an off-hand manner. If creationists really had the convictions in their own beliefs then they would be exposing falsified data, but they aren’t. Why? Because deep down I think they know the data is right.
I can tell you what is stopping creationists from going to those same rocks and doing their own measurements. It’s called money. Have you ever applied for a grant to test a creationist hypothesis? The government is certainly not giving it to you. Some creationists are now doing some of those tests with their own funds, with interesting results.

And the suggestion (not at this point an accusation) is not of conscious bias, but of unconscious bias. See my earlier reply to Swamidass.

RonSewell (C33):

You say,

I feel like I may be missing something basic in this thread. Is that not what crystallization does at time zero, reject daughter elements at the time of crystal formation? The same consideration applies to degassing of magma.
Degassing of magma is often confidently asserted. However, that article cited by Dalrymple (Dalrymple GB: “40Ar/36Ar analysis of historic lava flows.” Earth Planet Sci Lett 1969;6:47-55.) noted that a substantial number of subaerial lava flows had inherited argon different from air argon, and all of the samples contained argon, just mostly matching air argon and thus able to be subtracted away. In fact, in some of his samples, the argon found was enriched in Ar-36 compared with argon from air. The short version is that either Ar-36 diffuses into lava preferentially, presumably all the time, and we have no justification for subtracting out air argon rather than some fraction thereof, or lava does not degas. The latter possibility is why Dalrymple recommended using isochron Ar/Ar dating to account for inherited argon when he discussed the Vesuvius data.

As for crystallization rejecting daughter elements, the effect is only relative and not absolute, and perhaps more important, what could be called mineral dates are not preferred for Rb/Sr dating, but rather whole-rock dating. As Gunter Faure said (Principles of Isotope Geology (2nd ed). New York: John Wiley and Sons, 1986),

Igneous rocks of granitic composition may contain both mica minerals and K-feldspar, all of which can be dated by the Rb-Sr method. Ideally, all minerals of an igneous rock should indicate the same date which can then be regarded as the age of the rock. When mineral dates obtained from one rock specimen or from a suite of cogenetic igneous rocks are in agreement, they are said to be “concordant.” Unfortunately, “discordance” of mineral dates is more common than “concordance.” The reason is that the constituent minerals of a rock may gain or lose radiogenic 87Sr as a result of reheating during regional or contact metamorphism after crystallization from a magma. In such cases, the mineral dates generally are not reliable indicators of the age of the rock. We must therefore turn to the rocks themselves if we want to determine their ages.
So if you are looking for crystals that exclude strontium and include rubidium, the dates you get will be “too young”.

T_aquaticus (C35)

Most of what you said is accurate, although you left out that zircons are notoriously hard to reset to zero age by heating, and consequently are plagued by the inherited age problem. However, when you said,

The dates from each decay series should fall on the blue concordia line. As far as I am aware, this isn’t considered an isochron.
you apparently missed the fact that this line is also mimicked by a mixing line. The details are in my paper, p. 11. But I am not the only one to notice this. See Steiger RH, Wasserburg GJ: “Comparative U-Th-Pb systematics in 2.7 × 109 yr plutons of different geologic histories.” Geochim Cosmochim Acta 1969;33:1213-32.

Dan_Eastwood (C36),

Your comments are appreciated.

You say,

In statistical terms the measurement error (variance) is the sum of actual measurement variance plus the square of the bias.
In order to make an estimate of the variance, it seems that we must know what the bias is. At present, we do not.

One might be tempted to say that the variance puts a limit on bias. But this is true only if all results are included in the variance. That is why I argue for blinded tests, with all results published.

You say,

This pretty much exhausts my knowledge of geochemistry, but I will hazard one further opinion: It seems highly unlikely that any strong systematic bias should exist across all dating methods, and that such an oversight could exist for long without someone noticing and improving on it.
You might be right. IMO we should investigate the subject.

We still need an explanation of how Rb/Sr, U/Pb, and K/Ar decay chains could all be coordinated so that they give the same age for the same geologic layers.

I was never taught any such thing, and I highly doubt that this was ever the consensus position within paleontology.

Yes, it was just a belief. As stated before, I have yet to see any evidence which demonstrates that these features could not be preserved for 65 million years.

There are plenty of Christian universities that support or lean towards YEC. Liberty University is a good example. Many of them have tons of money. There is also the possibility of getting donations from YEC’s who support the cause. It’s completely doable.

How would you unconsciously measure the wrong concentrations of these isotopes?

How much non-radiogenic argon did the rocks have? Would it be enough to add hundreds of millions or billions of years to their actual age? How would the amount of inherited argon create ages that correlate with U/Pb and Rb/Sr dates from rocks in the same geologic layer? Again, if you are going to introduce a potential problem you still need to explain the consilience between methods.

When zircons melt it resets the clock. Again, at the time of crystallization nearly all Pb is excluded while U is included. What tiny amount of Pb is present only throws off the youngest of ages by any appreciable amount.

No, it isn’t. Mixing doesn’t occur in zircons because they exclude Pb.

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I don’t have a creationist hypothesis to test, but I have applied to the American Heart Association, a private charity, to test a cardiolology hypothesis.

There is nothing preventing creationist private charities from offering grants, is there?

The government is not preventing creationist charities from giving money to you.

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