> Glenn Morton has or had a page on C14 correlated against tree rings and
> varves. These data show that, done properly, C14 is a very reliable
> technique. The tree rings go back 10,000 years and the varves go back
> 40,000 years. I can't find it on his page, so if you contact him he
> should be able to give you details.
All this about 14C is well and good, but let's remember that you can't
date many rocks, much less the planet, using carbon. It is really
only used for organic material. YEC's like to
criticize 14C dating and say this somehow means the
earth is young. But if you want to date rocks you use U-Pb, Sm-Nd, K-Ar,
Lu-Hf if you are super spiffy, and Rb-Sr if you are daring.
The criticisms of YEC's against 14C (as if this had anything to do
with the age of the earth) only show ignorance about how
rocks, and in turn the earth, are dated.
Back to 14C, I believe it has also been calibrated against the U series,
which doesn't vary with belches from the sun.
Cheers,
C
*****************************************************
Charles W. Carrigan
Univ. of Michigan - Department of Geological Sciences
2534 C.C. Little Bldg.
425 E. University Ave.
Ann Arbor, MI 48109-1063
cwcarrig@umich.edu
"The point of having an open mind, like an open mouth,
is to close it on something solid."
-G.K. Chesterton
This archive was generated by hypermail 2b29 : Wed Sep 19 2001 - 20:24:03 EDT