Sun Aug 25 21:12:49 1996

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From: Mike Phillips 
Subject: Re: Carbon dating
Date: Sun, 25 Aug 1996 20:10:46 -0700
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>  From: "Dave Washburn" , on 8/25/96 4:13 PM:
>  Bob Waltz wrote:
>  > But I will observe that "temperature change," "weather change," and
>  > "chemical breakdown" have no effect on the results of C-14 dating,
>  > which is a nuclear process dependent *only* on the radioactive
>  > behavior of C-14.
>  
>  I believe his point was that the generation and uptake of C-14 in 
>  relation to other carbon isotopes is affected by these factors (as 
>  opposed to its decay rate, which you correctly point out is a 
>  constant nuclear process), and hence we can't really assume that 
>  quantities of C-12, C-13 and C-14 will have started out equal.  And 
>  without that equality factor, C-14 dating is on even less certain 
>  footing than we thought it was.

	Yes, that is what I was saying.  The rate of deposition is not a
constant, while the rate of decay is.  If you have an unanticipated variable,
you have too many variables (any variable unaccounted for by a formulaic
expression makes the result variable).  Yet, given the great amounts of time
we're dealing with, some results might actually be worth having around.  The
problem is that we can't be certain which results are worth keeping without
confirmation from other sources, hence, C-14 dating is not a stand-alone method
(or at least, shouldn't be, though it has been used as such at times).

-------------
Mike Phillips
mphilli3@indy.tdsnet.com

A word is not a crystal, transparent and unchanging;
it is the skin of living thought and changes from day
to day as does the air around us. - Oliver Wendell Holmes

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