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To: stormer
No. You see I already have a collection of Geology texts. When I go back to colleges and take classes, I like to take geology classes because I like the controversy. And even though I'm only ever there for one class (hour or hour and a half) I buy the book that the assignment for that class comes from. Some of them are actually pretty funny.

Right now I'm reading a fossils text: Life History of a Fossil, Pat Shipman, Harvard University Press, 1981, supposedly for advanced undergraduates and professionals. (This isn't for a class. I just saw the book and picked it up.) All these fairy tales have interesting segments. So here's one from this book:

Both radiometric and paleomagnetic dating are widely used to date rocks older than 100,000 years. Radiometric dating depends on the fact that radioactive atoms in the original environment are captured as the rocks solidify. Such atoms degenerate at a steady rate by giving off particles from their nuclei. Over time these atoms become either a new isotope of the original element or a new element. The time elapsed since the rock has lithified can be determined by measuring the proportions of the original parent atoms and the new daughter atoms. Of course if the rocks are reheated to a new molten state after their original lithification, the proportion of atoms will reflect the most recent heating and cooling, not the original one.
Well, silly me. Here, all along, I didn't think terrestrial heating or cooling could cause nuclear reactions. It just goes to show that all that Atomic and Nuclear Physics I took was a waste of time.

Still, I'd like to know about that 7000 mile diameter earth. To me the fact that no one even seems to want to guess indicates that they really don't know much about the 8000 mile diameter earth either.

ML/NJ

37 posted on 01/17/2012 7:09:29 PM PST by ml/nj
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To: ml/nj
I'm afraid I don't understand your confusion. The passage states that when rock remelts and then relithifies, the isotopic ratio is a reflection of that ratio at the time the melting took place. As to your contention that the Earth was once smaller, I am unaware of any compelling evidence that supports that.
38 posted on 01/17/2012 7:37:50 PM PST by stormer
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To: ml/nj
I like to take geology classes because I like the controversy.

Really? You like controversy? From reading your posts over the years...I would say "colr me SHOCKED" that you like controversy.

I would say you just like to argue.

43 posted on 01/18/2012 8:58:30 AM PST by NELSON111
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