Calilasseia

That's a simplifying assumption - uniform distribution of the material. A more sophisticated analysis that has the radionuclides absent from, say, the top 1 Km of crust would probably not result in significant alterations in the magnitudes of the results. Even then, there are places on Earth where the radionuclides are close to the surface - ask anyone who has bought a house in Cornwall recently, and has had to have the National Radioloigcal Protection Board check the house for Radon accumulation.

No, because as Joe Meert said in the original calculations (which used different data for the mass of the Earth - I obtained mine from the National Physical Laboratory) he was being generous toward RATE by picking a 500 year half life, because their own figure is a half life accelerated by a factor of a BILLION times, which means that they have the U²³⁸ half-life suddenly speeding up to just 4½ years. It's on the basis of that figure that I ended up with the wacky 10¹⁸⁰⁶ Kelvins core temp.

You would have to consult a professional geologist about this, and ask if the linearity is justified all the way to the core. But even so, a quick visit to the Schlumberger website (Schlumberger provides geological services to the oil industry) yields that my figures are reasonable, as in this little snippet and this apparently holds down to the depths at which Schlumberger's clients drill for oil. Of course once we hit the mantle proper, the relationship might take a different shape, but I did deliver this exposition as an elementary treatment of the subject. If I wanted to deliver a more sophisticated treatment, I would probably need to engage in the less than delightful world of solving second order partial differential equations numerically, which I can tell you is not for the faint hearted!

SpaghettiSawUs

CM,

I really must salute you. Not only are you providing a concise presentation of the evidence that even an idiot could understand, but you are dealing with Dave's typical debating traits with the accuracy of Zorro: whipping a great "Z" through each and every bit of it.

Your latest post is indeed a work of art - in both prose and content - a joy to read and re-read. It really is a pleasure to see you have a moment alone with Dave, it's been a while coming. I only hope that it has some benefit to Dave, given your profession, though I realise Dave would have to give "Hawkins' Demon" the elbow for it to do so.

In any event your debate posts have been of huge benefit to me, providing the perfect layman's (idiot's?) introduction to the science lake varve chronology. That, alongside the clear refutations of the best of YEC "counter-arguments" (logical fallacies, apples and oranges, misquotes and quotemines) promises to make a very useful educational resource.

I hope the mods go easy on Dave for the c&p, it could just be a bit of a habit and he didn't mean to do it (a bit like a smoker on a long haul flight having "just one drag" over the sink with the plug hole open to suck out the smoke). Surely the c&p was a mere slip of the mouse. Shame, if Dave had taken the time to cite the reference correctly it might never have been spotted. That was an excellent spot though, very thorough indeed of you to have picked up on it (now you remind me of a sharp nosed air-stewardess tapping on the toilet door ). I'm sure that if Dave didn't appreciate your diligence before, he certainly does now.

Thanks,
Spags

mung bean

I second the compliment. Lovely job, CM.
While I understand and largely agree with Dawkins' position re religion I have to say that some people are wonderful advertisements for faithheads.
In this instance I am not referring to Mr. Hawkins.

BWE

CM,

Your posts have been thoroughly enjoyable, professionally and courteously written, and well considered and deliberate. This last follows suit. I don't know how you resist the urge to tease our lop-eared muse but I fear that you will send him back to his cave by taking him seriously. As a human, it's easy to take him seriously- we've all got problems- but as soon as he gets it that you actually took him seriously, embarrassment becomes more likely.

Just my two cents.

Chili

. . . and we should all be happy that there is no history in Genesis if that is where we have to come full cirlce in real life.

Sven

But you calculate core temperatures. I don't see how radionuclides being close to the surface has any relevance for this.
On the other hand, if the radionuclides are actually concenctrated in the crust (did I understand this correctly?), you would actually get far higher temperatures at the surface. So your argument would actually be a best case scenario for David, no?

I see. But since you have all this in Excel/Basic, it should be easy to plug in 6000 / 10000 years. I'm just interested in the results (they should still be astronimocally large). Would this be possible?

OK, thanks!

JonF

Changes the thermal gradiient near the radiating surface. A very small effect on the core temperature.

Calilasseia

Well, I've already stated that those temperatures are calculated based upon an assumption of linearity of relationship, and admitted that a more sophisticated analysis may alight upon a different relationship.

Furthermore, the assumption of uniform distribution of radionuclides throughout the volume of the Earth makes at least some sense in the light of the fact that the principal materials bearing rich concentrations of radionuclides are igneous. Which means that they started life in the mantle. Therefore the mantle was the original source of those radionuclides. Moreover, convection is known to occur in the mantle, and indeed is what drives plate tectonics - here's a nice page explaining this. Therefore, given that convection exists, one can safely assume a reasonable homogeneity of mantle material (viscosity issues notwithstanding). Consequently, until a more sophisticated analysis involving separate treatments of crust, mantle and inner core, involving (it has to be said) some fairly nasty partial differential equations, is presented by someone with the necessary geological expertise, then this elementary treatment will have to suffice.

Just done this for 6000 years. The temperature gradient drops to around 47 K Km^-1, due to the fact that the original relationship is an exponential one, and due to the sizes of the assorted constants in that relationship. Massive inflation of the temperature gradient starts to kick in significantly sometime after we "accelerate" the half-life to less than 2,000 years.

Here are some figures for the temperature gradients (in K Km^-1) for different "accelerated" half-lives:

6000 years : 46.84
5000 years : 53.83
4000 years : 66.27
3000 years : 93.72
2000 years : 187.45
1000 years : 1,499.66
900 Years : 2,380.59
800 years : 4,241.70
700 years : 8,914.00
600 years : 23,394.7
500 years : 95,798.3
400 years : 767,830
300 years : 2,457,058
200 years : 2.516 x 10¹⁰
100 years : 2.705 x 10¹⁹

As you can see, the moment you get into an accelerated half-life that is less than 2,000 years, you start to hit the part where the curve is climbing ever more steeply, and by the time you get to less than 1,000 years, the curve is rocketing into temperature realms that result in at the very least, a permanently molten Earth, and at worst, an Earth that has become a ball of incandescent plasma.

So, basically, there's a very fine balance between "accelerated" decay rates that produce a slightly warmed up Earth, and rates that produce a molten Earth. Don't forget that the decay rate that is being compressed starts with a 4.5 billion year half life, so somehow that "acceleration" has to home in precsiely upon a value of the order of 2 million times smaller without veering too much either side of the "ideal" for RATE's purposes. This assumes of course that RATE is picking their "accelerated" decay rate in this fashion - they've chosen to pick a decay rate a billion times faster, i.e., a half-life for U²³⁸ of just 4.5 years, which pushes these figures into realms that Excel can't compute.

The resulting chart consists of a straight line bumping along the x axis followed by a sudden massive jump at the end, because the scale for the y-axis is in units 5 x 10¹⁸ in size, and the smaller data points don't show as a curve at that scale!

Incidentally, playing with this has told me that I need to revise my assumption of linearity all the way to the core, because that produces incorrect core temperatures when the actual empirically observed value of the temperature gradient is inserted into the linearity formula. Linearity should therefore be confined to the crust and possibly the upper layers of the mantle. However, if I can find a relationship that generates true core temperatures, I suspect that won't make a major qualitative difference to RATE's assertions, because they're STILL citing a decay rate acceleration that results in numbers too big for Excel to calculate even at the crust!

I could (if I wished to devote the time) fit a curve to empirical data and produce a function that spits out the temperature at depths all the way to the centre as a function of depth, then use that for core temperature calculation, but it would not make too much of a difference to RATE's unphysicality for the reasons already cited, namely that the surface of the Earth is already incandescent plasma once the U²³⁸ half life is accelerated to faster than 1,000 years.

Sven

Thanks, Calilasseia! :thumbs:

ericmurphy

After CM's most recent post, I do not see how Dave can possibly avoid dealing with radiometric calibration curves anymore. He simply cannot avoid explaining how all the various calibration curves can be not only wrong, but wrong in different ways for different reasons, but still be all wrong by the same amount.

I'm guessing he'll avoid dealing with them anyway, not even out of dishonest, but simply because he cannot see what the problem is. No matter how many times we explain it to him, he doesn't get it. I gave him a detailed explanation for how calibration curves work, and he responded by saying it "isn't an explanation."

But could he tell me what I'd left unexplained?

If I were CM, I would stay on this one topic for the remainder of the debate, and not allow Dave to change the subject. If calibration curves are correct, the earth is a minimum of 60,000 years old, and hence Genesis is false.