RE: How can we know how old fossils are?
May 2, 2019 at 1:45 pm
(This post was last modified: May 2, 2019 at 2:22 pm by Anomalocaris.)
(May 2, 2019 at 2:49 am)The Valkyrie Wrote:(May 2, 2019 at 1:32 am)Anomalocaris Wrote: What if they stopped putting on new rings years ago?
Then they're dead and don't matter.
Speaking rings, tree rings provide both a independent confirmation of the general accuracy of straight (as in unsophisticated) C14 dating, as well as an reliable bench mark for fine scale calibration for sophisticated C14 dating that corrects for the fact that atmospheric ratio of C14 and C12 has fluctuated slightly over time, so the age inferred from assumption that the initial C14 ratio in organisms over history had always been the same as they are now would actually drift slightly from their true age.
By matching rings in remains of successive generations of dead trees, it is possible to provide an exact calibration for C14 dating back to more than 12,000 years.


