On Sep 24, 2007, at 4:01 PM, Steven M Smith wrote:
> Baumgardner continued: There was a "frantic quest in the laboratories
> to find sources of C14 contamination." This led to all those papers
> in the radiocarbon literature. After eliminating or accounting for
> all known sources of C14 contamination, the labs attributed the
> remainder of C14 to 'in-situ' contamination; C14 that was actually in
> the sample. Now the laboratories subtract a "standard background from
> the actual C14 measurement that is equal to about 40,000 years." The
> laboratories do this to "avoid the embarrassing reality that
> essentially all fossil carbon contains C14.
No, laboratories do this because AMS mass separation is not perfect,
and there is always a small background that must be subtracted.
> Baumgardner related how they had obtained 10 coal samples from the
> Penn State University Energy Institute Coal Sample Archive that ranged
> in age from Paleozoic to Mesozoic to Cenozoic. These samples were
> sent to a professional radiocarbon dating laboratory. Each sample was
> analyzed 4 times. We were shown a PowerPoint table with the results:
> All samples were between 44.5-57.x ka and the average age was 49,600
> years.
...
> But this wasn't the end of his talk. In additional to coal, "C14 has
> been found in Precambrian graphite, marble, and calcite." Therefore
> with their coal samples, RATE included a diamond in their initial
> submission for C14 dating. Although the lab had trouble analyzing the
> diamond, eventually they returned a date that was just about the same
> as the coal samples.
>
> "Diamonds are thought to be 1 to 3 billion years old. And because
> of high bond strength, diamond is almost impossible to contaminate."
>
> So Baumgardner obtained 6 African diamonds from deep mines and
> submitted them for C14 dating. These diamonds gave the "same results
> that are already in the literature." So why is there C14 in 1 to 3
> billion-year-old diamonds? (1) Perhaps it is "primordial C14" from
> the moment of creation; or (2) Perhaps 'Accelerated Nuclear Decay'
> during the Flood generated high levels of neutrons that created C14 in
> the diamonds. Today's levels of neutrons in the mines are 10,000 to
> 100,000 times to low to create this much C14.
It would be interesting to know where they sent these coal and diamond
samples, how they were prepared, and whether or not backgrounds were
subtracted. Based on what he said earlier, I suspect he is quoting raw
numbers without background subtraction; in this case his dates are just
the AMS background.
I found one reference to C14 and diamond in the literature (by former
colleagues):
http://llnl.confex.com/llnl/ams10/techprogram/P1246.HTM
But the authors were not trying to measure C14 IN diamond. They were
using diamond to eliminate all sources of C14 in the sample so they
could characterize the background of the instrument itself.
Kirk
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Received on Tue Sep 25 01:42:50 2007
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