From: lippard@skyblu.ccit.arizona.edu (James J. Lippard)
Newsgroups: sci.skeptic,talk.origins
Subject: Re: Young earth creationist logic NOT!
Date: 21 Aug 92 05:55:00 GMT
Followup-To: sci.skeptic, talk.origins
Distribution: world,local
Organization: University of Arizona
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In article <536@texbell.sbc.com>, lm8637@tnessd.sbc.com (Lou Montgomery (214+464-1049)) writes...
>        On the subject of God creating an Earth with the appearance
>       of age; I do not buy this for a moment. However, might we
>       consider the following?
>        Could the Earth look old to we humans because our methods
>       for determining age are flawed? I'm not sure. Let's take
>       a scientific look and see what falls out.
>        Carbon 14 dating.

C14 dating has nothing to do with dating the age of the earth, because
it is limited to the last 15,000-20,000 years.

>       1) LIVING Mollusks have been dated by the carbon 14 procedure
>       and assigned an age of 2300 years old. These results were
>       recorded in Science, vol. 130, Dec. 11, 1959.

From Gerald E. Aardsma, "Myths Regarding Radiocarbon Dating," _Impact_
No. 189 (March 1989), the Institute for Creation Research:

"MYTH #3.  The shells of live freshwater clams have been radiocarbon
dated in excess of 1600 years old, clearly showing that the radiocarbon
dating technique is not valid.

"The shells of live freshwater clams can, and often do, give anomalous
radiocarbon results.  However, the reason for this is understood and the
problem is restricted to only a few special cases, of which freshwater
clams are the best-known example.  It is not correct to state or imply
from this evidence that the radiocarbon dating technique is thus shown
to be generally invalid.
   "The problem with freshwater clams arises because these organisms
derive the carbon atoms which they use to build their shells from the
water in their environment.  If this water is in contact with significant
quantities of limestone, it will contain many carbon atoms from dissolved
limestone.  Since limestone contains very little, if any, radiocarbon,
clam shells will contain less radiocarbon than would have been the case if
they had gotten their carbon atoms from the air.  This gives the clam
shell an artificially old radiocarbon age.
   "This problem, known as the 'reservoir effect,' is not of very great
practical importance for radiocarbon dating since most of the artifacts
which are useful for radiocarbon dating purposes and are of interest to
archaeology derive from terrestrial organisms which ultimately obtain
their carbon atoms from the air, not the water."

>       2) Nature, vol. 225, March 7, 1970, reported a carbon 14 test
>       done on organic material contained in the mortar of an English
>       castle. Although the castle was known to be 787 years old, the
>       carbon 14 test gave an age of 7370 years.
> 
>       3) Anarctic Journal of The United States, vol. 6, 1971 reported
>       that freshly killed seals were carbon 14 dated at 1300 years.
>       In the same series of tests mummified seals that had been dead
>       30 years were dated by this method at 4600 years old.
> 
>          Why have the dating results been so inaccurate? Contrary to
>       a very important assumption on which carbon 14 dating is based,
>       not all plants absorb radioactive carbon equally. Recent 
>       research has revealed a previously unknown internal weight
>       differentiating mechanism in some plants which rejects the heavy
>       radioactive carbon atoms - while still allowing the absorption
>       of normal carbon atoms. Thus, at death, these plants ( and the
>       animals that eat them) have abnormally low levels of carbon 14.
>       When these remains are dated they give the FALSE impression of
>       being VERY OLD.

Could we have a source for this one?  Also, I suspect that each of the
above sources (I intend to check) offers an explanation of the error in
each case.

>          As with other radiometric dating methods, the carbon 14
>       method depends on several assumptions. One of the most important
>       assumptions, in order for this method of dating to work, is
>       that the amount of radioactive carbon in the Earth's atmosphere
>       in the past would have been constant. This would mean that the
>       rate of formation of radioactive carbon would had have to equal
>       the decay rate in the age in which the specimens lived. Secondly,

No, this is not only not assumed, it is known (from tree ring dating)
to be false, and is corrected for.

>       it must be assumed that the decay rate was the same in the past
>       as it is today. Another important factor is that NO cotamination

Do you have any reason to believe the decay rate was different in the
past?

>       of radioactive carbon could have occurred since the death of the
>       specimen. There are a number of enviornmental factors to consider
>       which indicate that the RATE OF RADIOACTIVE CARBON FORMATION HAS
>       NOT BEEN CONSTANT throughout the history of the Earth.

Again, this is known and corrected for.

>          My intent here was not to enter the fray between the creation
>       and evolution advocates, merely to try and demonstrate the flaws
>       in this discussion of an Earth created with the APPEARANCE of
>       age.
> 
>          If you students of this discussion are interested in discussing
>       other methods of dating such as, uranium-lead, potassium-argon,
>       radioactive half-life, halo method, radiohalos, isochron or any
>       that may be of interest to either side, simply post into this
>       newsgroup and I will respond in a scientific, non-offensive
>       manner.

The halo method?
Why don't you tell us what's wrong with the rubidium-strontium isochron
method.  What is the explanation for the results of isochron dating?
What is the explanation for the convergence of dates from different
radiometric dating techniques and other dating techniques?

Jim Lippard              Lippard@CCIT.ARIZONA.EDU
Dept. of Philosophy      Lippard@ARIZVMS.BITNET
University of Arizona
Tucson, AZ 85721
Newsgroups: sci.skeptic