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Author Topic:   Peanut Gallery for Great debate: radiocarbon dating, Mindspawn and Coyote/RAZD
Coyote
Member (Idle past 2106 days)
Posts: 6117
Joined: 01-12-2008


Message 46 of 305 (711079)
11-14-2013 10:32 PM
Reply to: Message 45 by RAZD
11-14-2013 10:29 PM


Re: Great Debate Message 15 and Message 16
I'll be joining this thread as the Great Debate is pretty much done. At least I'm not participating there until there is some rationality on the other side.
Somehow I had hoped for better.
Silly me.

Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.
Belief gets in the way of learning--Robert A. Heinlein
How can I possibly put a new idea into your heads, if I do not first remove your delusions?--Robert A. Heinlein
It's not what we don't know that hurts, it's what we know that ain't so--Will Rogers
If I am entitled to something, someone else is obliged to pay--Jerry Pournelle

This message is a reply to:
 Message 45 by RAZD, posted 11-14-2013 10:29 PM RAZD has seen this message but not replied

  
Pressie
Member
Posts: 2103
From: Pretoria, SA
Joined: 06-18-2010


Message 47 of 305 (711081)
11-14-2013 10:50 PM


Thank you
This thread is a keeper. What a gold mine of information, neatly compressed in a few pages.
Thank you all very, very much for your hard work!
Edited by Pressie, : No reason given.

  
NoNukes
Inactive Member


(1)
Message 48 of 305 (711103)
11-15-2013 7:37 AM


Mindspawn states the following:
The half-life of Uranium-Thorium is not independently established in a laboratory, but measured against existing dating methods and so is bound to evolutionary assumptions and this explains the consilience in the other 3 locations. Uranium-Thorium dating even calibrates against radiocarbon dating and so these dates become meaningless as independent verifiction of radiocarbon dates.
Perhaps that sorry thread can be ended quickly after all.
ABE:
http://www.sciencedirect.com/...rticle/pii/S0009254199001576
quote:
We have re-determined the 234U and 230Th half-lives to be 245,250490 years (2σ) and 75,690230 years (2σ), respectively. Using high precision thermal ionization mass spectrometric (TIMS) methods, we measured 234U and 230Th atomic ratios in 4 different materials that were likely to have behaved as closed systems for 106 years or more:
The new half-lives agree within error with previously determined values; however, errors in our values are generally smaller than those in the earlier determinations.
Edited by NoNukes, : No reason given.

Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)
I believe that a scientist looking at nonscientific problems is just as dumb as the next guy.
Richard P. Feynman
If there is no struggle, there is no progress. Those who profess to favor freedom, and deprecate agitation, are men who want crops without plowing up the ground, they want rain without thunder and lightning. Frederick Douglass

Replies to this message:
 Message 50 by Percy, posted 11-15-2013 8:30 AM NoNukes has replied
 Message 52 by JonF, posted 11-15-2013 8:36 AM NoNukes has replied

  
JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


(1)
Message 49 of 305 (711104)
11-15-2013 8:00 AM


Mindie should re-read message 1: "Evidence should be limited to accepted science, and not include numerous rabbit-holes which lead nowhere. "What-ifs" with no evidence supporting them should not be permitted."
False as I pointed out in a previous thread with a reference.
but measured against existing dating methods and so is bound to evolutionary assumptions and this explains the consilience in the other 3 locations.
False
Uranium-Thorium dating even calibrates against radiocarbon dating
False
Ice cores are precipitation sensitive, each large snowfall/rainfall would by its very nature create a layer, please explain why those layers are annual and not sensitive to each major precipitation during the year.
Of course that's well known to those with a clue. Ice cores are taken from areas of very low precipitation, and are counted by seasonal markers because the compression of the snow removes the "lines" between layers.
which explains the consilience due to consistent worldwide rainfall patterns.
Consistent worldwide rainfall pattern??? WTF, he's gone totally bonkers.
The rest of his message is a feeble attempt to shift the burden of proof.

Replies to this message:
 Message 56 by RAZD, posted 11-15-2013 9:08 AM JonF has replied

  
Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


(2)
Message 50 of 305 (711105)
11-15-2013 8:30 AM
Reply to: Message 48 by NoNukes
11-15-2013 7:37 AM


mindspawn writes:
The half-life of Uranium-Thorium is not independently established in a laboratory...
Even though it doesn't seem to help Mindspawn, don't we still want to correct the misunderstandings and misinformation? Creationists have a way of cramming huge amounts of misinformation into a small number of words, and the above 13 words are no exception.
  1. "Uranium-Thorium" is a dating method, not an element with a half life.
  2. Uranium is one element, Thorium is another.
  3. Both Uranium and Thorium have a number of isotopes. Isotopes are a family of types of the same element with the same number of protons in the nucleus but different numbers of neutrons. Each isotope will have a different half-life, except for stable isotopes which do not decay and therefore do not have a half-life.
  4. The Uranium referred to is 234U with a half-life of 245,000 years.
  5. The Thorium referred to is 230Th with a half life of 75,000 years.
  6. The half-lives of both 234U and 230Th have been measured in the laboratory.
I think Coyote should return to the thread and not worry about Mindspawn ever getting it, just provide correct information and untangle any misunderstandings that might confuse others.
--Percy

This message is a reply to:
 Message 48 by NoNukes, posted 11-15-2013 7:37 AM NoNukes has replied

Replies to this message:
 Message 51 by Coyote, posted 11-15-2013 8:34 AM Percy has seen this message but not replied
 Message 53 by JonF, posted 11-15-2013 8:41 AM Percy has seen this message but not replied
 Message 57 by NoNukes, posted 11-15-2013 9:24 AM Percy has replied

  
Coyote
Member (Idle past 2106 days)
Posts: 6117
Joined: 01-12-2008


Message 51 of 305 (711107)
11-15-2013 8:34 AM
Reply to: Message 50 by Percy
11-15-2013 8:30 AM


I think Coyote should return to the thread and not worry about Mindspawn ever getting it, just provide correct information and untangle any misunderstandings that might confuse others.
I specifically started that thread to deal with radiocarbon dating, not useless rabbit holes.
I specifically stated in the OP that I wanted to restrict posts to established science, not useless "what-ifs."
That is all Mindspawn is presenting now. I'm not interested.
If he wants to discuss radiocarbon dating I'll return to the thread.

Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.
Belief gets in the way of learning--Robert A. Heinlein
How can I possibly put a new idea into your heads, if I do not first remove your delusions?--Robert A. Heinlein
It's not what we don't know that hurts, it's what we know that ain't so--Will Rogers
If I am entitled to something, someone else is obliged to pay--Jerry Pournelle

This message is a reply to:
 Message 50 by Percy, posted 11-15-2013 8:30 AM Percy has seen this message but not replied

Replies to this message:
 Message 54 by RAZD, posted 11-15-2013 8:43 AM Coyote has replied

  
JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


(1)
Message 52 of 305 (711109)
11-15-2013 8:36 AM
Reply to: Message 48 by NoNukes
11-15-2013 7:37 AM


The half-life of Uranium-Thorium is not independently established in a laboratory, but measured against existing dating methods and so is bound to evolutionary assumptions and this explains the consilience in the other 3 locations. Uranium-Thorium dating even calibrates against radiocarbon dating and so these dates become meaningless as independent verifiction of radiocarbon dates.
Perhaps that sorry thread can be ended quickly after all.
As I posted before, not only is calibrating a decay rate by another decay rate very unusual, it's never done for isotopes in the Uranium series.
Begemann et al have a good summary in the introduction of Call for an improved set of decay constants for geochronological use. It's not open access, but I have a copy:
quote:
Accurate radioisotopic age determinations require accurate decay constants of the respective parent nuclides. Ideally, the uncertainty on the decay constants should be negligible compared to, or at least be commensurate with, the analytical uncertainties of the mass spectrometric measurements entering the calculations. Clearly, this is not the case at present. The stunning improvements in the performance of mass spectrometers during the past three decades, starting with the seminal paper by Wasserburg et al. (1969), have not been accompanied by any comparable improvement in the accuracy of the decay constants.The uncertainties associated with direct half-life determinations are, in most cases, still at the percent level at best. The recognition of an urgent need to improve the situation is not new (cf., e.g., Renne et al., 1998; Min et al., 2000a); it has presumably been mentioned, at one time or another, by every group active in geo- or cosmochronology. The present contribution is intended to be a critical guide to the existing experimental approaches. Except in a few cases, we do not evaluate the individual reports on decay constants, and we also do not make any recommendations as to which values should be considered correct and be used by the dating community at large. This must, in our opinion, be left for existing commissions to decide, following the precedent of Steiger and Jager (1977). Three approaches have so far been followed to determine the decay constants of long-lived radioactive nuclides.
1. Direct counting. In this technique, alpha, beta or gamma activity is counted, and divided by the total number of radioactive atoms. Among the difficulties of this approach are the self-shielding of finite-thickness solid samples, the low specific activities, imprecise knowledge of the isotopic composition of the parent element, the detection of verylow- energy decays, and problems with detector efficiencies and geometry factors. Judged from the fact that many of the counting experiments have yielded results that are not compatible with one another within the stated uncertainties, it would appear that not all the difficulties are always fully realized so that many of the given uncertainties are unrealistically small, and that many experiments are plagued by unrecognized systematic errors. As the nature of these errors is obscure, it is not straightforward to decide which of the, often mutually exclusive, results of such counting experiments is closest to the true value. Furthermore, the presence of systematic biases makes any averaging dangerous. Weighted averaging using weight factors based on listed uncertainties is doubly dubious. It is well possible that reliable results of careful workers, listing realistic uncertainties, will not be given the weights they deserve—this aside from the question whether it makes sense to average numbers that by far do not agree within the stated uncertainties.
2. Ingrowth. This technique relies on measuring the decay products of a well-known amount of a radioactive nuclide accumulated over a well-defined period of time. Where feasible, this is the most straightforward technique. Ingrowth overcomes the problems encountered with measuring large fractions of low-energy b-particles, as in the case of 87Rb and 187Re. It also comprises the products of radiation- less decays (which otherwise cannot be measured at all) like the bound-beta decay branch of 187Re and the possible contribution to the decay of 40K by electron capture directly into the ground state of 40Ar. Among the drawbacks of this approach is that the method is not instantaneous.The experiment must be started long before the first results can be obtained because long periods of time (typically decades) are required for sufficiently large amounts of the decay products to accumulate. Ingrowth-experiments further require an accurate determination of the ratio of two chemical elements (parent/daughter) as well as an accurate determination of the isotopic composition of parent and daughter element at the start of the accumulation (see below). Moreover, because of the hold-up in the chain of intermediaries, for uranium and thorium measuring the ingrowth of the stable decay products in the laboratory does not work at all.
3. Geological comparison. This approach entails multichronometric dating of a rock and cross-calibration of different radioisotopic age systems by adjusting the decay constant of one system so as to force agreement with the age obtained via another dating system. In essence, because the half-life of 238U is the most accurately known of all relevant radionuclides, this amounts to expressing ages in units of the half-life of 238U.
This procedure is less than ideal, however.The different radioisotopic dating systems were developed, and as a rule are being utilized, because different parent/daughter element pairs are affected in different ways by different geological processes. Thus, employing a variety of element pairs often allows to distinguish chemical, thermal, mechanical, or other processes capable of fractionating or homogenizing the chemical signature of its minerals during a rock’s history. It is the sequence of such events that one wants to learn about.This, in turn, implies that there is the practical problem of selecting a sample where the initial event starting the radioisotopic clock was so short and simple as to be truly point-like in time, and whose subsequent perturbations were totally nonexistent. As illustrated by the case of early comparisons between Rb-Sr and K-Ar ages, or K-Ar and U-Pb ages, on non-retentive materials like micas, feldspars, and uraninites in plutonic rocks, simple concepts about ideal samples that were considered valid a quarter of a century ago have not withstood the test of time. Our present perception of isotopic closure has been changed as a result of improved understanding of mineralogy and isotope systematics; consequently, now the definition of a point-like event is more restrictive than that implicitly assumed by the studies that influenced Steiger and Jaeger (1977). The obvious requirements are that the two isotopic systems being compared are exactly coherent due to simple thermal, chemical, and mechanical histories. In addition to selecting a sample which was rapidly quenched from a magmatic stage, it is of vital importance to ascertain that the sample escaped any retrogressive change of mineralogy and especially any exchange with fluids, and was spared any later disturbance, chemical and/or thermal. This can be investigated by detailed microchemistry of major and trace elements. Vagaries and problems potentially encountered with the standard Pb-Pb and U-Pb ages used for this kind of calibration have most recently been discussed by Tera and Carlson (1999).
And I have no idea how he could have come up with even a hint of calibrating U-Th dating from 14C dating in his reference (his link is broken but it's Radiocarbon calibration curve spanning 0 to 50,000 years BP based on paired 230Th/ 234U/ 238U and 14C dates on pristine corals).
Edited by JonF, : Fix second link

This message is a reply to:
 Message 48 by NoNukes, posted 11-15-2013 7:37 AM NoNukes has replied

Replies to this message:
 Message 62 by NoNukes, posted 11-15-2013 11:44 AM JonF has replied

  
JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


Message 53 of 305 (711111)
11-15-2013 8:41 AM
Reply to: Message 50 by Percy
11-15-2013 8:30 AM


I think Coyote should return to the thread and not worry about Mindspawn ever getting it, just provide correct information and untangle any misunderstandings that might confuse others.
I would like to agree with you, but it is obvious that it's a thankless task and Mindie can come up with an infinite number of impossible fantasies.
I don't know if anyone here was reading talk.origins around a decade ago, but it took literally years and many threads to convince Zoe Althrop that the mathematics of isochron dating were valid and could be used to derive the original parent/daughter ratio. With many side excursions such as convincing here that X/0 was not equal to X.
Mindie reminds me of her but with a much broader range of fantasy.

This message is a reply to:
 Message 50 by Percy, posted 11-15-2013 8:30 AM Percy has seen this message but not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 54 of 305 (711112)
11-15-2013 8:43 AM
Reply to: Message 51 by Coyote
11-15-2013 8:34 AM


tag-team?
If you want, and mindspawn agrees, I can take over for you

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 51 by Coyote, posted 11-15-2013 8:34 AM Coyote has replied

Replies to this message:
 Message 55 by Coyote, posted 11-15-2013 8:50 AM RAZD has replied

  
Coyote
Member (Idle past 2106 days)
Posts: 6117
Joined: 01-12-2008


Message 55 of 305 (711116)
11-15-2013 8:50 AM
Reply to: Message 54 by RAZD
11-15-2013 8:43 AM


Re: tag-team?
RAZD, sure, that would be good.
I'm willing to discuss radiocarbon dating, but there are just too many side topics being thrown out with no evidence and I have neither the time nor the patience for those.

Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.
Belief gets in the way of learning--Robert A. Heinlein
How can I possibly put a new idea into your heads, if I do not first remove your delusions?--Robert A. Heinlein
It's not what we don't know that hurts, it's what we know that ain't so--Will Rogers
If I am entitled to something, someone else is obliged to pay--Jerry Pournelle

This message is a reply to:
 Message 54 by RAZD, posted 11-15-2013 8:43 AM RAZD has replied

Replies to this message:
 Message 65 by RAZD, posted 11-15-2013 3:37 PM Coyote has seen this message but not replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 56 of 305 (711120)
11-15-2013 9:08 AM
Reply to: Message 49 by JonF
11-15-2013 8:00 AM


you appear to have missed a quote.
Uranium-Thorium dating even calibrates against radiocarbon dating
False
I wonder if mindspawn is confusing calibration with correlation ... when one system is compared to another to see if there is a correlation, that is not calibrating either system.
cal•i•brate
[kal-uh-breyt] verb (used with object), cal•i•brated, cal•i•brat•ing.
  1. to determine, check, or rectify the graduation of (any instrument giving quantitative measurements).
  2. to divide or mark with gradations, graduations, or other indexes of degree, quantity, etc., as on a thermometer, measuring cup, or the like.
  3. to determine the correct range for (an artillery gun, mortar, etc.) by observing where the fired projectile hits.
  4. to plan or devise (something) carefully so as to have a precise use, application, appeal, etc.: a sales strategy calibrated to rich investors.
cor•re•la•tion
[kawr-uh-ley-shuhn, kor-] noun
  1. mutual relation of two or more things, parts, etc.: Studies find a positive correlation between severity of illness and nutritional status of the patients. Synonyms: similarity, correspondence, matching; parallelism, equivalence; interdependence, interrelationship, interconnection.
  2. the act of correlating or state of being correlated.
  3. Statistics. the degree to which two or more attributes or measurements on the same group of elements show a tendency to vary together.
  4. Physiology . the interdependence or reciprocal relations of organs or functions.
  5. Geology . the demonstrable equivalence, in age or lithology, of two or more stratigraphic units, as formations or members of such.
Another word used is consilience:
quote:
In science and history, consilience (also convergence of evidence or concordance of evidence) refers to the principle that evidence from independent, unrelated sources can "converge" to strong conclusions. That is, when multiple sources of evidence are in agreement, the conclusion can be very strong even when none of the individual sources of evidence are very strong on their own. Most established scientific knowledge is supported by a convergence of evidence: if not, the evidence is comparatively weak, and there will not likely be a strong scientific consensus.
The principle is based on the unity of knowledge; measuring the same result by several different methods should lead to the same answer. For example, it should not matter whether one measures the distance between the Great Pyramids of Giza by laser rangefinding, by satellite imaging, or with a meter stick - in all three cases, the answer should be approximately the same. For the same reason, different dating methods in geochronology should concur, a result in chemistry should not contradict a result in geology, etc.
Perhaps the next version of my age dating correlations should use consilience as a more appropriate description.
Enjoy.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)

This message is a reply to:
 Message 49 by JonF, posted 11-15-2013 8:00 AM JonF has replied

Replies to this message:
 Message 60 by JonF, posted 11-15-2013 10:24 AM RAZD has replied

  
NoNukes
Inactive Member


Message 57 of 305 (711123)
11-15-2013 9:24 AM
Reply to: Message 50 by Percy
11-15-2013 8:30 AM


Even though it doesn't seem to help Mindspawn, don't we still want to correct the misunderstandings and misinformation? Creationists have a way of cramming huge amounts of misinformation into a small number of words, and the above 13 words are no exception.
Of course we do want to correct misunderstanding. I appreciate your providing of some detail, but how did I add to the confusion by citing an article that provided independent values for the half life of each of the isotopes?
I agree that Coyote's returning to the thread would be best, but I can forgive him entirely if he does not want to do it. If I were in a Great Debate with mindspawn, I would be quite testy by now.
But yes, the correct thing to do would be to simply, and dispassionately explain the set of coincidences that mindspawn relies on, because the low probability of that coincidence speaks volumes. He should then challenge mindspawn.
Then Coyote can expound correctly on the details of C-14 dating. I'm sure that's what most of us were hoping for. I don't believe more than a post or two would be required to dismiss mindspawn before the science talk could begin.

Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)
I believe that a scientist looking at nonscientific problems is just as dumb as the next guy.
Richard P. Feynman
If there is no struggle, there is no progress. Those who profess to favor freedom, and deprecate agitation, are men who want crops without plowing up the ground, they want rain without thunder and lightning. Frederick Douglass

This message is a reply to:
 Message 50 by Percy, posted 11-15-2013 8:30 AM Percy has replied

Replies to this message:
 Message 59 by Percy, posted 11-15-2013 10:16 AM NoNukes has replied

  
New Cat's Eye
Inactive Member


(1)
Message 58 of 305 (711129)
11-15-2013 9:45 AM


Dishonesty
I can't take Mindspawn's posts seriously when he starts off being dishonest from the get-go.
My main problem with carbon dating is its calibration against tree ring chronology...
Bullshit. His main problem with carbon dating is that it contradicts his belief in a young Earth.
All he's doing is looking for ways to hide that contradiction, regardless of whether or not he has to be honest about it.

  
Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 59 of 305 (711133)
11-15-2013 10:16 AM
Reply to: Message 57 by NoNukes
11-15-2013 9:24 AM


NoNukes writes:
I appreciate your providing of some detail, but how did I add to the confusion by citing an article that provided independent values for the half life of each of the isotopes?
I don't remember seeing that citation when I replied. I see there was an edit, so maybe it wasn't part of your original response? The time of my reply is when I finished, not when I started, I've been multi-tasking.
--Percy

This message is a reply to:
 Message 57 by NoNukes, posted 11-15-2013 9:24 AM NoNukes has replied

Replies to this message:
 Message 61 by NoNukes, posted 11-15-2013 11:31 AM Percy has seen this message but not replied
 Message 66 by RAZD, posted 11-15-2013 3:39 PM Percy has seen this message but not replied

  
JonF
Member (Idle past 168 days)
Posts: 6174
Joined: 06-23-2003


Message 60 of 305 (711136)
11-15-2013 10:24 AM
Reply to: Message 56 by RAZD
11-15-2013 9:08 AM


I wonder if mindspawn is confusing calibration with correlation.
No, he explicitly wrote that he thinks that U-Th dating is calibrated, not correlated, by 14C dating, and this calibratino is used to extend the range of U-Th beyond that of 14C. Message 10:
quote:
I am still looking into how they originally calibrated Uranium-Thorium dating , if they calibrated this according to carbon dating, this ruins the claimed consilience, and in the following link it appears this is what they actually do. They seem to assume radiocarbon dates are accurate , and then apply uranium-thorium methods to these dated coral samples. In this way they can establish a calibration curve for uranium-thorium dating which they can use for periods earlier than carbon dating can function. If radiocarbon dating gives out incorrect dates, this would mean so would uranium-thorium dating, their corroboration is meaningless if uranium-throrium dating is calibrated using radiocarbon dating.
His link is broken but it's Radiocarbon calibration curve spanning 0 to 50,000 years BP based on paired 230Th/ 234U/ 238U and 14C dates on pristine corals

This message is a reply to:
 Message 56 by RAZD, posted 11-15-2013 9:08 AM RAZD has replied

Replies to this message:
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