There is a radiocarbon study that should be of interest to
people interested in radiocarbon dating. It is:
Kitagawa, H., and J. van der Plicht (1998) Atmospheric
radiocarbon calibration to 45,000 yr B.P.; Late glacial
fluctuations and cosmogenic isotope production. Science.
vol. 279, no. 5354, pp. 1187-1190.
The abstract reads in part:
"More than 250 carbon-14 accelerator mass spectrometer
dates of terrestrial macrofossils from annually laminated
sediments from Lake Sulgetsu (Japan) provide a first
atmospheric calibration for almost the total range of the
radiocarbon method (45,000 years before present)."
The article concludes that results of the dating confirms
the German pine chronology and consistent with data from
European and marine varve sediments and dating of corals
by both uranium-thorium and radiocarbon dating.
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From: Rich Daniel[SMTP:rwdaniel@dnaco.net]
Sent: Thursday, May 27, 1999 12:08 PM
To: evolution@calvin.edu
Subject: C-14 dating
> > >The only truly reliable methods of dating past events are carbon-14,
> > >dendrochronology and uranium series dating, but these are good only back
> > >to about 350.000 years.
> >
> >...carbon-14 dating only goes back to about 10,000 years....
>
> Hold off a sec in your rant. It seems perfectly okay to me to pick the
> oldest valid dating method of the three and characterize them by that one to
> establish the inability to date MORE than that. I'm sure he does indeed know
> c-14 is only good to 10k yrs back, but uranium series and dendrochronology
> allow dating much older.
Argh! I don't have a reference handy, but I'm reasonably certain that
C-14 works up to at least 50k years, and maybe 100k.
Rich Daniel rwdaniel@dnaco.net http://www.dnaco.net/~rwdaniel/