Geologists and dating (India Basins Half a Billion Years Older Than Thought)

Hi Joe,
Few questions about Fig 14 in your paper before we start a discussion:Are the Concordia plots corrected by removing the common Pb that was present initially when the zircon crystallized? If yes, how did you determine the initial Pb content?
Can you give us the raw data of the amount of all isotopes of Uranium and Pb in each sample?Thanks.

Please provide the paper by Williams and the raw data. Without the raw data and the correction algorithm you used, I would not be able to start a discussion.

I disagree with the statement "you cannot get a lower age range by arguing that we incorrectly applied the common lead correction."If you subtracted less than the correct the amount of common present during crystallization, you would obtain an older age.I can't possibly attack you if I don't understand the justification behind the correction method and if you do not disclose your raw data and your method of subtracting the common Pb.It's OK if you are busy now, please scan it whenever you are free or maybe someone else here who is in university and has access to this journal, please scan it for us.

OK, I don't need the Williams paper since it applies to a particular instrument. What I was looking for is how geologists determine the amount of Pb present initially during crystallization.On page 13 of your paper, you wrote regarding the grains from the Rewa group "Most of the grains analyzed showed very discordant dispersions between 206Pb/238U and 207Pb/235U ages as well as high common Pb."Regarding the grains from the Bhander group, you wrote, "The detrital zircon sample processed from the Upper Bhander sandstone (sampled from sites 43, 44 and 45, Rajasthan section) yielded numerous datable grains with varying degrees of concordance."What is it that you observed in Rewa group that made you conclude that there is high common Pb in those grains?
What makes you believe that the Bhander group contained very little common Pb during crystal formation?

Please give me the spreadsheet containing the raw data. I assume your spreadsheet contains all the formulas used to arrive at your end result from the raw data. This is basically what I want. I want to first understand exactly what you have done, then start the discussion.What I understand about the Concordia diagram is what is explained at http://www.tulane.edu/...lson/geol212/radiometric_dating.htmBut that website doesn't explain how to calculate (Pb206/Pb204)_o in equation 9. I don't know if geologists apply the isochron method that is used to find out (Sr87/Sr86)_o to find out similarly for (Pb206/Pb204)_o. Or is there some other method?I will be in a position to start a discussion only if I see your raw data and understand your calculations.

Joe,
Pls confirm whether the same isochron method is used to determine (Pb206/Pb204)_o. Do you know of any measured data that supports the statement above? I think the statement above should be something that can be proven if true. For example, someone can measure the amount of Pb from a zircon grain from a volcano that just erupted and compare it to the amount of Pb present in the magma of that volcano.For example, if the Pb content in the zircon is 0.1ppm, and the Pb content in the magma is 10ppm, then the statement above is justified. Then we can also proceed to estimate how much of error results from the common Pb present. That's not a problem, as I have Minitab (a statistical software) and I think that I too can analyse the data. Minitab does have many inbuilt statistical tests. The conversation I want to have is the common Pb correction. If there are better arguments to be had, we can consider them later. But first I want to see your raw data and understand how you determined the common Pb. I don't understand what this means, atleast if you provide the raw data and show me an example of the spike, I might be in a position to understand what you are saying. OK, it's your wish. If you don't disclose the raw data, it won't be possible for me to apply any statistical test to your data, and I don't see any point in continuing this discussion.No one here other than you knows how you determined the common Pb correction. Percy thinks you applied the isochron method (something that I doubt). JonF thinks it is not necessary to do any correction because Pb is not incorporated during solidification, but you have admitted that zircons from the Rewa group have high common Pb. Even if I 'abuse' your work, at least at the end of the day other members here would understand your research.

I want to analyze your data and then conclude whether or not the common Pb correction is small. My faith in your word is weak. Please do send all Uranium and Pb isotope raw data that you have measured in a word document. I am not in a position to do the research myself, so I have to rely on other people's data. If I had faith in your word, I will not require your data. I have doubts on your methods and calculation, so I want the raw measured data. But definitely I'm not in a position to collect the data myself.I am hoping to engage in a more meaningful discussion after I get the raw data. Indeed, Jesus himself said, "Blessed are those who have not seen yet have believed." I admire those who believe you without having seen your data, may I be allowed to be a doubting Thomas.

I believe JM has not manipulated the raw data. Statistical tests can be done on the raw data to see if it fits a model. Not forever.But again, I believe that if JM gives me the raw data, he will not give me manipulated data. What would JM gain by giving me manipulated data?

I am not questioning your integrity. I have made it clear in a previous post that I don't believe you will manipulate your data. The very fact that I am asking you for raw data implies that I am not questioning the integrity of your raw data.What I intend to do is statistical tests and calculations on your raw data to see if it fits your model.Let's put it this way: I'm not questioning your integrity, but your method. Basically what I understand from your previous posts is this: If it fits the Concordia, there is very little common Pb. I will accept your raw data at face value without questioning it. I won't call it 'abuse', just doing my own calculation and sharing it with others. In which post did I call you a liar? Is asking for raw data and not accepting your word that your data fits the Concordia amount to calling you a liar? I prefer if you give me the data in a MS word format without printing and snail mailing it to me. If it's in a word format, I can copy and paste the data from Word to Excel. If you send me a printed copy, I will have to retype your data.Can you reconsider your deal to send me a printed copy? What if I can find statistical tests that prove that the raw data (not the common Pb corrected data) fits my model better than yours? Will you then admit that I am the only one who understands the data?

I may not get the opportunity to prove Joe’s analysis is wrong. The practice here is to close the thread after it reaches ~300 posts. There is already too much of noise in this thread, 20 posts per day (most of them being non-technical posts). At this rate, the 300 post limit will be reached before I even start to analyze Joe’s data.I have given my home address to Joe, and assuming that I get the data after 2 weeks, I will still need a few weeks to analyze his data. So my next post will definitely take some time, maybe a month or so. Can we use this thread just to discuss JM’s data and calculations?
As the owner of this website, can you close this thread temporarily to avoid this thread reaching the 300 post limit even before I start analyzing the data?
I don’t want to waste my time responding to this type of questions and accusations that I have called Joe a liar. I have every right to analyze his data before accepting his word and ignore questions not related to JM’s paper.

Joe,
I do understand how radiometry works, but I don’t know how to interpret your data. If I know the measured amount of Pb206 (in ppm), and the amount of U238 (in ppm), as well as other isotopes of U and Pb, I can start doing the calculations.In a previous post you mentioned, “
Having said that, the corrections applied here follow pretty closely with (minor modification for the ICP method) the Stacey and Kramers (1975) models.”This is the kind of data I don’t want. Basically I want to do the calculations and check whether the raw data fits my model or the Concordia model. I don’t know how the Stacey and Kramers model does common Pb correction, and at this point I do not want to discuss whether the Stacey and Kramers model is correct.I am fully aware that you have told me several times already that the common Pb correction is negligible in many of your samples, so its really not necessary for us to discuss the Stacey and Kramers model.So can you teach me how to obtain all the U and Pb isotope data in ppm.The format I am looking for is something like the format given in table 1 of http://www.geology.wisc.edu/...y/zircons/Wilde2001Nature.pdfThe kind of data I don’t accept in table 1 of this paper by Wilde is the ratio of 206Pb*/238U. This is because the 206Pb* is ”corrected’ using some correction algorithm.The kind of data I accept is the ratio of 204Pb/206Pb in table 1. This is measured raw data. They have also mentioned their 1 sigma error level. I also accept measurement errors.This is what I accept and what I don’t. Basically what I want is the raw data without the assumed common Pb during crystallization being corrected.If you want me to accept the Stacey and Kramers model, please point me to lab experiment where someone was able to theoretically predict the amount of common Pb that could be incorporated into zircon during crystallization. I don’t know whether zircon can be crystallized in the lab from some aqueous solution. The researcher can always add a small amount Pb impurity in the solution, and then predict the amount of impurity that will be incorporated into the zircon after crystallization. Or point me to a researcher who was able to predict how much of Pb would be there in a zircon from a volcano that erupted during the past few years.If researchers are unable to predict the amount of Pb that could be incorporated into a newly formed zircon, it also follows that they are unable to correct the common Pb in a zircon that formed long ago. This is why I want to check ”uncorrected’ data against my model.Thanks.

Is JM my student or something? Who am I to ask JM to do the calculations for me? I prefer to do it myself.

I don't know. If I have the raw data I could check the correlation factor of the measured data and my model. If the correlation factor is higher when the measured data is fitted to the Concordia curve, then my model is not good. If the data fits my model with better correlation, then I would think that my model is better.What geologists do when the data doesn't fit their Concordia curve, is start making speculative excuses such as meteorites bombarded these zircons, therefore Pb was removed. If measured data doesn’t fit the model, and if speculative ideas such as Pb removal, Pb addition, U removal, U addition are allowed to creep in, then the science is not objective science, but just attempts to defend the U-Pb dating method. If such speculative ideas are allowed, then nothing will ever disprove the theory.There have been experiments that have proven zircon is resistant to wear and tear. What is the probability of a meteorite hitting the earth? Even when they hit the earth, isn’t it more likely that the zircon would be under the surface, so the top layers of the earth protect them from such bombardment? What is the probability that geologists would find a zircon that was shocked by a meteorite?JM and his team are better than other geologists. In their paper on page 13 he states: “From 23 grains analyzed, only 3 yielded concordant ages. Two grains yield an age of 1555 Ma, and a single grain yielded an age of 1053 Ma. Because of the limited sample size, these results are not considered further.”They did not resort to speculative ideas, and just said, “these results are not considered further”. If these data which do no fit the Concordia model fit my model, I would think that my model is good, and should be published. I publish to a personal website.One of the reasons why Aristotelian physics survived 2000 years, even after Galileo’s time because human beings have never been objective in their thinking when comparing different models. If they want to defend a particular model, they will be able to find excuses.
In your opinion, if the measured data correlates better with my model, do you think any geologist will change his mind, or will they still resort to speculative ideas such as Pb removal, Pb addition, U removal and U addition? It is the normal practice of any researcher to do his own calculation to prove his model. If I want to prove my model, I should be the one trying to prove it.
In message 68 he has asked me to stop asking questions and has asked to show him how his data proves that the earth is 6000 years old. This clearly implies that he wants me to do the calculation myself.

I know that. Do you know that geologists have measured the Pb206/Pb204 in magma today, and lavas in different parts of the world have very different Pb206/Pb204 ratios? A quick google search I performed shows me that this ratio is ~15 in some parts of the world, and ~19 in other parts.Do you think that the correction model that geologists believe in can correct the differing ratios in different parts of the world? Or do you think that only now the Pb206/Pb204 ratio differs in different parts of the world? Perhaps you think that 1 billion years ago this ratio was a constant in all magma all over the world? You are the ignorant one who thinks that the correction model actually works.

You understand me very well. I have just finished writing a report on a more accurate way of doing U-Pb dating. Since it involves equations, I don't know how to use html and dBCodes to compose it here. It is available at Google Sites: Sign-in Yes, it is a very simple statistical test. With the online data that I have come across, I don't think I can calculate the absolute age, but I think if someone measures all the relevant isotope data in the decay chain of Uranium, and if someone spends a lot of time thinking how to crunch that data, it may be possible to determine the true age.