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Is Carbon
Dating Reliable?
Question: What about radiocarbon
dating? Is it accurate?
RESPONSE: I asked several people
who know about this field. Their responses are numbered below.
1. C14 dating is very accurate for wood
used up to about 4,000 years ago. This is only because it is well
calibrated with objects of known age. Example: wood found in a grave of
known age by historically reliable documents is the standard for that time
for the C14 content. This standard content of C14 can then be used for
wood not associated with a historically documented date. Dates up to this
point in history are well documented for C14 calibration.
For object over 4,000 years old the method
becomes very unreliable for the following reason: Objects
older then 4,000 years run into a problem in that there are few if any
known artifacts to be used as the standard. Libby the discoverer of the
C14 dating method was very disappointed with this problem. He understood
that archaeological artifacts were readily available. After all this what
the archeologist guessed in their published books.
Some believe trees are known to be as old as
9,000 years. They use tree rings
as the calibration standard. A lot of people doubt this claim for various
good reasons I wont go into here. We believe all the dates over 5,000
years are really compressible into the next 2,000 years back to creation.
So when you hear of a date of 30,000 years for a carbon date we believe it
to be early after creation and only about 7,000 years old. If something
carbon dates at 7,000 years we believe 5,000 is probably closer to reality
(just before the flood).
Robert
Whitelaw has done a very good job illustrating this theory using about
30,000 dates published in Radio Carbon over the last 40 years. One of the
impressive points Whitewall makes is the conspicuous absence of dates
between 4,500 and 5,000 years ago illustrating a great catastrophe killing
off plant and animal life world wide (the flood of Noah)!
I hope this helps your understanding of carbon
dating. If you have any more questions about it don't hesitate to write.
2. I just listened to a series of
lectures on archaeology put out by John Hopkins Univ. The lecturer talked
at length about how inaccurate C14 Dating is (as 'corrected' by
dendrochronology). The methodology is quite accurate, but dendrochronology
supposedly shows that the C14 dates go off because of changes in the
equilibrium over time, and that the older the dates the larger the error.
Despite this she continually uses the c14 dates
to create 'absolute' chronologies. She says this is ok so long as you take
into account the correction factors from dendrochronology. (They
conveniently forget to mention that the tree ring chronology was arranged
by C14 dating. The scientists who were trying to build the chronology
found the tree rings so ambiguous that they could not decide which rings
matched which (using the bristlecone pine). So they tested some of the
ring sequences by C14 to put the sequences in the 'right' order. Once
they did that they developed the overall sequence. And this big sequence
is then used to 'correct' C14 dates. talk of circular reasoning!!!!
3. Even if the rate of decay is constant,
without a knowledge of the exact ratio of C12 to C14 in the initial
sample, the dating technique is still subject to question.
4. Traditional 14C testing assumes
equilibrium in the rate of formation and the rate of decay. In fact, 14C
is forming FASTER than the observed decay rate. This skews the 'real'
answer to a much younger age.
You can find
some further good information here:
http://www.cs.unc.edu/~plaisted/ce/dating.html#Carbon
-- read the full page if you get the chance. And, there is a good
overview of radiometric dating as well here:
http://www.creationinthecrossfire.com/documents/Radiomentric%20Dating/
Radiometric%20Dating.html
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