<HTML>On September-03-01 06:21
Don Baronešwrote:š
>Hi John:
>I believe originally it was thought that this
>decay of Carbon 14 was constant throughout time
>but now apparently adjustments are made to
>compensate for any known fluxuatons in the cause
>of this decay. Whether all of them have been
>found still remains a bone of contention. At
>least this what I believe I have read.
The **decay** of radiocarbon, as any radioisotope,
has remained constant, contrary to what YE creationist
propoganda falsely claims, throughout geologic time.
The main concern with radiocarbon dating is that the
**production** of radiocarbon in the atmosphere has
varied throughout the last 45,000 years for which the
method is useful.
This concern is rectified by the use of calibration
curves using radiocarbon dating of tree-rings and
varved lake deposits and paired radiocarbon dating
and Uranium-Series dating of speleothems and
corals. The calibration curves now extend as far
back as 45,000 BP contrary to claims may by
Sean Hancock.
Some web pages are:
Go read: "Radiocarbon Calibration"
[
units.ox.ac.uk]
[
units.ox.ac.uk]
Calibration
[
www.rdg.ac.uk]
Accuracy of Radiocarbon Dating By John Stockwell
[
www.tiac.net]
CALIB Radiocarbon Calibration
[
depts.washington.edu]
[
calib.org]
Radiocarbon-Related Information Sources
[
www.radiocarbon.org]
PE-04. A 45.000 YEAR VARVE CHRONOLOGY FROM JAPAN\
[
www.cio.phys.rug.nl]
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, pp. 1187-1190 (20 Feb 1998).
Stalagmite Triples Radiocarbon Dating Effectiveness
[
unisci.com]
Radiocarbon calibration using 230Th ages of submerged
speleothems from the Bahamas
[
gmb.ggy.bris.ac.uk]
Beck, J.W., Richards, D. A., Edwards, R. L., Silverman,
B. W., Smart, P. L., Donahue, D. L., Hererra-Osterheld,
S., Burr, G.S., Calsoyas, L., Jull, A. J. T. and Biddulph, D.
(2001) Extremely large variations of atmospheric 14C
concentration during the last glacial period. Science.
vol. 292, no. 5526, pp. 2453-2458. (29 June 2001).
Have Fun:
Keith</HTML>
