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Author Topic:   Problems with Radiometric Dating?
RAZD
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Message 46 of 46 (483709)
09-23-2008 8:29 PM
Reply to: Message 41 by eial
09-22-2008 11:57 PM


Can you have too many correlations?
Thanks eial,
I think the idea of “calibrating” C14 with tree rings is great. Yet, I see a couple of problems here. First of all, tree rings are not always annual. So, we have to assume these are annual rings, I am assuming for the most part they are, but over a long period (say thousands of years), a few extra rings here and there could give an older date for the tree. Just a thought, I am not willing to die on this mountain. Correct me if I am mistaken, but the oldest trees I have been able to find, based on their rings alone, have been in the 4500 range.
Correct for single living trees that have been discovered and where core samples have been taken to measure their age.
You also have problems of missing rings, which leads to false young age if not corrected. Dendrochronologists know what to look for and how to eliminate these false and missing rings from the overall data.
They also can piece together tree rings from one tree with those of another, because the tree rings also preserve information about climate - wider rings from longer warmer summers, thinner rings from cool short summers, and because the pattern of climate from one year to the next is rather random than static, these patterns in the rings can be matched from one sample to another.
There are also three continuous tree ring chronologies currently known in the world, one for the Bristlecone Pine in Arizona, and two for the Post Oak, one in Germany and one in Ireland. These three totally independent chronologies each extend to over 8,000 years, and when they are matched up for climate information they have a net error of some 37 years over that time. That's a 0.5% error.
The carbon-14 data also preserves climate data, as the amount of C-14 produced in the atmosphere depends on it's own "climate" - variation in sun activity that produces the cosmic rays that cause Nitrogen atoms to be converted into C-14 atoms (one of the reasons it varies, rather than has a constant equilibrium value), and we can match the "C-14 climate" info from C-14 to each of tree rings along with the tree ring climate. That's a lot of correlation in just a few pieces of evidence.
See Age Correlations and an Old Earth: Version 1 No 3 (formerly Part III) for more information on this and other calibration systems.
It is interesting that as you look at the graph, and just for kicks, drop the 5K and beyond, the graph appears to start a significant divergent from the linear path it appears to be taking.
And further on it comes back to the straight correlation line, showing that C-14 does indeed vary with age, and that when corrected to actual dates from the C-14 ages that the artifacts are older.
Again, an assumption has to be made that all the “daughter” mass actually is daughter mass (came from the parent isotope), and was not already present in the sample. This is a very large assumption, especially since the consequence of being off could mean the difference in millions of years versus tens of thousands. How this estimation can be done with any accuracy is beyond me.
There is no "parent-daughter" system in C-14: it works because the carbon-14 is being constantly renewed by cosmic radiation converting nitrogen atoms into new C-14. What is measured is the ratio of C-14 to C-12, and as long as the sample got it's carbon from the atmosphere (or from plants that got it from the atmosphere (or from animals that got it from plants that got it from the atmosphere (or ... etc))) and as long as we know (or reasonably estimate) the proportion in the atmosphere at the time the organism lived we can calculate the age based on the ratio {(C-14)/(C-12)}now/{(C-14)/(C-12)}then (you will notice that this is dimensionless, so we don't need accurate mass of the original, only an accurate ratio of C-14 to C-12.
What correlations are you referring to that tell us the actual age of objects that goes beyond say, 5K years?
See Age Correlations and an Old Earth: Version 1 No 3 (formerly Part III).
If we have correlations that tell us actual object ages, why are we even belaboring the issue of radioactive dating? We must know what these calibrations are, and see how many assumptions there are in these. If we are not accurate with our calibration tools, calibrating against an inaccurate instrument is useless. This sounds like we are getting somewhere.
Because once we have correlated a radiometric dating method and validated its accuracy, then we can use it to date things where we can't count the rings/layers/ages.
Enjoy.
Edited by RAZD, : subtitle

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This message is a reply to:
 Message 41 by eial, posted 09-22-2008 11:57 PM eial has not replied

  
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