The Earth is > 10,000 Years Old

PrefaceI am disappointed that I am not going to have the chance to address any of Con’s rebuttals to my radiometric dating case. Oh well. Anyway, I will use my round to rebut Con’s positive case and then give a comparative analysis in my conclusion.Magnetic Field DecayHypothesisThe mechanisms by which the Earth’s magnetic field is still an unsolved problem in science. While there are multiple hypothesis, and while there does exists a leading hypothesis (dynamo model) for an explanation of exactly how the Earth gets it’s magnetic field, I have no interest in defending it, as one could make up any number of hypothesis for the Earth’s magnetic field and be of comparable credibility to the Humphries’ model (i.e. none).Con has presented one possible model but has provided absolutely no reason why we should think it is more likely than not to be true, or even mostly representative. Moreover, it needs to be not only most likely true, but also most likely true over the conditions of Earth’s past. This is a gigantic oversight on Con’s behalf, assumptions need to be justified, not assumed! To quote Christopher Hitchens:“I don’t have to know, you do. You’re the one who says you know, not me.”It’s not my place to provide an alternative explanation, I only need to show Con hasn’t justified his preferred one. Con could go ahead and refute leading models of the Earth’s magnetic field, but it wouldn’t bring him an inch closer to affirming his preferred one.One thing I need to address is Con’s assertion that the magnetic field is decreasing exponentially, I would like to know exactly where Con gets this claim from because even a cursory glance at the data points plotted clearly show that an exponential fit is dubious:[1] Of course, the data doesn’t preclude a genuine exponential decay relationship, but virtually any relationship can be fit to the data of this limited quantity and with this degree of variance. A straight line would fit equally well, for example. I am not advocating that the data is prescriptively a linear relationship (straight line), only that attributing any relationship to this data is quite frankly, absurd. Even Humphries’ own data doesn’t show the relationship he wants:[2]Exponential Decay Fit: Linear Fit: Argument for a Young Earth First, we need to unpack Pro’s argument and Con’s core assumptions:1. According to Con’s model, the magnetic field can only decay2. If the magnetic field can only decay, then it could only have been stronger in the past3. If the magnetic field could only have been stronger in the past, then it reaches a limitI suspect Con will not disagree with my portrayal of his argument. I can freely agree that the Earth’s magnetic field could not be infinite, or massive in the past due to physical considerations, but I don’t need to agree that the Earth’s magnetic field was ever continually stronger in the past. If the Earth’s magnetic field was not always decreasing, or in a state of flux with periods where the magnetic field becomes stronger of weaker, then suddenly Con doesn’t have an argument.Ironically, it so happens that IF the Earth was in a phase of magnetic field strengthening, Con would almost certainly be issuing a parallel argument for a >10,000 year old Earth, since a model could easily be assumed where the Earth’s magnetic field had to “start from somewhere”, and couldn’t have been less than 0.Magnetic Field as a State of FluxGiven Con simply has not justified his assumptions that the Earth’s magnetic field decay is a one-way street of decline, these arguments are not required to reject it, but I will provide them for sake of completion.IF the Earth’s magnetic field was a state of flux, then we would expect to see evidence of changes in the field’s intensity in the past, as well as the present. If the Earth’s magnetic field has always been in decline, then we wouldn’t expect to see any evidence of this.We already know of at least 171 examples of magnetic field reversals, black and white evidence of the Earth’s field being in a state of flux.[3] We know this from analysis of the polarisation of ferromagnetic minerals, with minerals at specific rock layers running opposite to today’s field, or in concordance with it. Regardless of whether or not the dates are accurate, the fact remains that the field reversed multiple times in the past, and this reversal has been recorded in a plethora of geological records, such as the 1,000 meter expanse of Steep’s mountain sequence. With such a reversal, an obvious association and mechanism for a cyclical increase/decrease of magnetic field strength arises. Moreover, these observations are not expected from the Humphries’ model, and only ad hoc reasoning can account for it (which does nothing but weaken the hypothesis).Moreover, the Sun’s magnetic field is known to be in a state of flux, in an 11 year cycle. Granted the Sun is a very different body to the Earth (with significantly more powerful convection processes, etc.), but the very fact the Sun’s magnetic field is obviously in a state of flux seriously damages the confidence that the Earth’s is not.Radioactive DatingI will add a little fuel to the fire by highlighting some of the pragmatic considerations with the method.Testing for ContaminationBecause zircon readily excludes lead, and not uranium, the practical contamination issues actually lead to underestimation of the real age of the rock, since worst case scenario is that some radiogenic lead gets washed out of exposed samples, which leads to a lower lead/uranium concentration, and thus a younger date. Therefore a case for contamination is virtually impossible to make on all samples gathered so far, which universally demonstrate an old age of the samples.Lead contamination, although extremely unlikely, is easily tested for by:1. Measuring the concentration of the sister lead isotope – 204Pb2. Checking for discord between decay dates found by 235U and 238U Sister IsotopeLead-204 is a primordial isotope, so names because it is not generated by any radiogenic process, thus essentially all Lead-204 that exists on Earth is from its formation. 204Pb consists of 1.4% of all lead, with 206Pb and 207Pb consisting of 24.1% and 22.1% respectively. Thus, the relative concentration of 204Pb could only have been greater in the past.[4]This is useful because IF there was any non-radiogenic lead that somehow contaminated the sample which would make the samples at most 10,000 years old then then we would certainly expect: 1. To observe 204Pb within that contamination (min, 1.4%) 2. To observe approximately a 24.1:22.1 ratio of 206Pb:207Pb These checks are very straightforward with the same equipment used to get the respective concentrations of U/Pb, thus these checks are trivial. If there are any small contaminations, then it can be trivially corrected for, if there are large contaminations, then the results are useless. The reason why we would expect 204Pb contamination is because all isotopes of lead are essentially chemically identical, with virtually identical reactivity, solubility, and other chemical properties. Thus any chemical process that is affected by one isotope of lead, is identically affected by another. There is no way for any natural process to differentiate (there is a reason why uranium enrichment is such a pain to do).If the Earth was only 10,000 years old, and contamination really did explain the results, then the concentration of Pb-204 in the samples must be at least 1.4% of the total composition, but we never see anything close to this in the literature.[6]Discord235Uonly has a half life of 703.8MA, over 6 times less than U238. Thus Pb207 accumulates at a much faster rate relative to 235U than 206Pb does relative to 238U. Because of this, we essentially have two independent dating methods for the price of one, which provides an extremely simple check for concordance. If contamination occurred, then we would expect a discord between the dates calculated from each isotope, unless there is some freakish statistical fluke. Thus, to give a numerical example, observing a 3:1 Pb/U ratio would mandate a subsequent observation of a 0.8 Pb/U ratio. Observation of deviations of this would be clear evidence of contamination or other factors. Again, from the literature, these deviations are the exception, not the norm, and essentially always in the direction of lead loss, not lead gain, leaving to underestimation of dates, not overestimation.Moreover, this is also a method to check for changes in the decay rates if it were even possible, again it would be a complete statistical fluke for the two ratios to line up if radioactive rates were accelerated in the past, especially considering fundamental physics would have to drastically change. The fact that we simply don’t see such significant discord is exceptionally strong evidence against such acceleration in the past.ConclusionI have sought to justify at length radiometric dating in this debate and I have. I have gone over the assumptions with a fine toothed comb, and demonstrated that rejecting these assumptions leads to absurd conclusions. Moreover, the physics and chemistry involved are very well understood, and radioactive decay is known down to it’s fundamental principles in quantum tunnelling.In comparison to Con’s positive case, Con simply has not justified his assumptions, one of which is a dubious assumption that the Humphries model of the Earth’s magnetic field is accurate and correct. Given that this model has little, if any evidential support, let alone support that would grant significant confidence in the model in making strong predictions/retrodictions, it follows that Con has rather spectacularly failed to uphold the antithesis.As such, a Pro vote is required.References1. http://tinyurl.com...2. http://tinyurl.com...3. http://tinyurl.com...4. http://gji.oxfordjournals.org...5. http://en.wikipedia.org...6. http://tinyurl.com...