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Radiometric dating of items with a known age

  1. Jun 2, 2012 #1
    I apologize if this has been discussed before. I haven't been able to locate an adequate answer to my question through searches.

    I enjoy debating with creationists; it's a bit of a cheap thrill. I'm sure many of you can relate. One of my favorite topics is the supposed unreliability of radiometric dating.

    I was wondering if anyone has come across a site which lists significant items in history which have a known age, that were dated using radiometric methods?

    I have a couple text books with examples like samples from the eruption of Mt. Vesuvius in 79 AD, but I was wondering if I could pull some more examples from your collective knowledge.

    Thanks a lot!
  2. jcsd
  3. Jun 2, 2012 #2
    Dead Sea scrolls maybe?

    Santorini eruption

    Note the discrepancy between archeologic evidence and other datings, treerings and 14C. Notice that the volcanic markers in the GISPII ice core (with counted annual layers) show a big spike at 3572 years BP. BP is 1950 - when the carbon dating method was invented. So that would be 1622 BC so thats 6 years short of the treering dating and nicely close to the average radiocarbon dating.
    Last edited: Jun 2, 2012
  4. Jun 2, 2012 #3
    Cool, thanks.

    I'm very familiar with how carbon dating works, and how it converges with other radiometric dating and other methods.

    Dating methods of all kinds fascinate me for some reason. I guess I just appreciate the engineering of the techniques.

    If you run across anything else, let me know. Thanks for the links. :)
  5. Jun 3, 2012 #4
    When debating with creationists on radiometric dating you have to be aware of how they will "cheat" too. For example, anyone familiar with C14 dating knows that you cannot date sea life with it. The carbon that appears in sea life can already be hundreds of years old. You will almost always get an anomalously high age for any sea life dated by C14. They will also date things with the potassium/argon method when the sample is much too young to get any reasonable date out of it. Much like trying to time a hundred yard dash with a calender. It cannot be done so that you can get any meaningful data out of the test. Creationist have also been know to carbon date a fossil that would not have any C14 in it at all. They forgot that the shellac that the fossil had been painted with to help keep it together was a source of young carbon. It was no surprise when they got a false date for the fossil using this methodology.

    You can find a lot of these abuses of creationists at Talk Origins. One of the best sites for debunking creationist nonsense. Here is a link to the seal story there:

    Last edited: Jun 4, 2012
  6. Jun 4, 2012 #5
    Yeah. I've done quite a lot of debating about radiometric dating and have come across just about every argument that creationists have made for decades.

    What it boils down to is they are not willing to learn how it actually works. They hear these arguments from apologists that never get retracted when they are debunked, so we are left arguing the same **** over and over.
  7. Jun 4, 2012 #6
    Radio carbon dating for submerged biota is possible nowadays, thanks to calibration to annual coral growth layers. See the calibration table marine09.

    It remains a bit tricky though due to ocean current dynamics causing changes in reservoir age

    I would advice not to discuss science with indogmatrination.
  8. Jun 23, 2012 #7
    Definitely check out, "Age determinations by radiocarbon content: checks with samples of known age" by Arnold and Libby (1949). http://hbar.phys.msu.ru/gorm/fomenko/libby.htm

    Creationists will commonly object that decay rates were different in the past. Point out that heat is released from decay and decay rates necessary to cram the decay we see around us into 6000 years would vaporize the planet. Also, there is a statistical improbability of different isotopes differentially decaying in the past at different rates and arriving at the same dates when we compare them now.

    Another common objection is that the rocks were not started at a "zero" date. Potassium-Argon dating works because argon (a gas) is boiled out of a melt. Also, we can examine crystals and see if they contain any entrapped argon.

    Debating with creationists can be fun (I have done more than my fair share), but I find that it is often a waste of time that could be spent doing something productive. Take care!
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