Dating from the Adams and Eves Threads

Listen this time, double-bogie, and answer me:How does your "contamination" get into the cellulose and lignin of leaves and twigs, and into the chitin of bug parts, AT PRECISELY THE SAME RATE? For all that, how does your "contamination" get into cellulose or lignin AT ALL?WRITE ME THE CHEMICAL REACTION, GOLFER!

But, dear Golfer, if you'll trouble yourself to read the paper we are discussing, you will see that they hand-picked actual leaves, stems, and bug parts out of the Lake Suigetsu cores. Not kerogen. I know a little about kerogen, y'know: it goes on to make oil. Neither is a process that happens in a mere 100,000 years at 20 degrees C.

Post 206 immediately above yours just subtracted about fifteen from that five, too. Is anticoherence a word?

Cellulose isn't kerogen. Bug legs and wings aren't either.

1221 posts here, and you still haven't realized that all radiodating methods "start the clock" only when the mineral (or living thing, for 14C) solidifies? Wow, Golfer! Why don't you pick "Osmium" for your next screen name? Or maybe "neutron star matter"?

Very little doubt about tree rings or ice core layers either one - both types of measurement have been repeated too many times all over the Earth. Radiometric dating includes C14 dating, but also refers to six or eight other types of radioactive elements. Most are used for dating things much older than C14 can go.

Easily done, Rox: Science 20 February 1998:
Vol. 279. no. 5354, pp. 1187 - 1190

Robin, you were puzzling, on your thread with Faith, about how half-lives of things like potassium 40 are determined. "Half-life" is just one of the alternate ways to express the rate at which an isotope decays. An example experiment would be to put a kilogram of potassium next to a Geiger counter and count the "blips" that the counter makes at various times over a year or two. The rate would be some number on Day 1, due to the 0.117 grams of potassium-40 present (and measured by independent means) in the kilogram, and the rate would slowly decline, as less and less potassium atoms are there to be able to decay each passing day.From the change in rate over time, it's just a very simple mathematical manipulation to express the "rate constant" as a half-life - it's an alternate way to say exactly the same thing: "How fast does this stuff decay?"I'm going off to play with
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where you can run your own experiment to determine one. Note that you don't have to run your experiment for a whole 1.7 billion years, though. Longer means more accuracy, but isn't at all required if you measure rates closely enough.This message has been edited by Coragyps, 12-29-2005 12:27 PM

Another half-life link:
Half_Life

From nuclear chemistry - potassium decays to argon, rubidium to strontium, samarium to neodymium....etc. By actually measuring it in the lab - the pdf that JonF linked tells exactly how. And they knew which elements to look at from work going back to Marie Curie. Any element that gives off radiation has a half-life - it's just that only a few occur naturally and have long enough half-lives to use for dating.

That's even more incoherent that usual. Consider a sediment particle - coal, perhaps - with a nitrogen atom in it. What about that as a target? Yes, it's because N14 is lighter, but not because of any atmospheric distribution. N14 and N15 are very well mixed in air. Bacteria use N14 and N15 at different rates precisely, and only, because of the difference in atomic mass - the heavy nitrogen is typically slower to go through any one reaction. Kinda like I was slower than I was when I weighed 40 pounds less than now.

It doesn't sound even remotely like fusion. Fusion, hot, cold, or lukewarm, means putting smaller nuclei together to make bigger ones. Alpha decay might be thought of as a special case of fission where a big nucleus breaks up into a nucleus that weighs 4 amu less and a helium.
And this has nothing to do with talc turning into kerogen and diatoms in Japanese lakebottoms.

Golfer;Bullcrap.