Date: 22 Feb 94 00:48:10 To: All Subject: Hovind on Radiometric Dating Here's another page
Date: 22 Feb 94 00:48:10
From: Rich Fox, Univ
To: All
Subject: Hovind on Radiometric Dating
From: rfox@charlie.usd.edu (Rich Fox, Univ of South Dakota)
Organization: The University of South Dakota Computer Science Dept.
Here's another page of Hovind nonsense, for comment.
Once again, I'll [Lippard] collect replies and send
them to Babinski for his debate.
Several Faulty Assumptions Are Used in all Radiometric
Dating Methods. Carbon 14 is used for this example:
1. Atmospheric C-14 is in equilibrium. This
assumption is wrong. It has been shown that the amount
of C-14 in the atmosphere is still increasing.
Libby in 1952 wrote (in _Radiocarbon Dating_) that
cosmic ray intensity over the past ca. 20000 years
probably fluctuated. He did assume that intensity
averaged over ca. 1000 years had not fluctuated
significantly. He therefore concluded that atmospheric
C14 has been in equilibrium (production = decay). By
1958 the assumption was shown to incorrect and today
there are detailed, refined corrections based on
dendrochronology (discussed below) in place. The
bottom line: equilibrium is not assumed and variation
in equilibrium is adequately controlled.
Hovind's "still increasing" is informative.
Actually, variation in cosmic ray intensity over time
has produced cyclical fluctuations in the C14
reservoir. Judging from "still", he sees the recent
past as a moment in a uniform, linear accumulation of
C14 from zero to equilibrium. Hovind's view is classic
uniformitarianism, a view which most creationists decry
(but, like Hovind, unkowingly use).
1 (con't ). It has been estimated that the C-14 in the
earth's atmosphere would reach equilibrium (the
formation rate would be equal to the decay rate) in
about 30,000 years. Research indicates that the amount
of C-14 is still increasing and is only 1/3 of the way
to equilibrium.
This evidently is an attempt to invalidate the alleged
equilibrium assumption. So far as I can tell, the
30,000 "estimate" derives from Henry Morris's
(Scientific Creationism, p. 161, 164) argument from
incredulity, and nowhere else. Morris arbitrarily
limits C14 dating to 29000 years ago, because at that
point only 1/32 of the original C14 content remains in
the dead organism. Morris thinks its "doubtful" that
any smaller amount can be reliably measured. They can
and have been - up to 40,000 years for conventional C14
dating, and 50,000 years for accelerator mass
spectography (AMS). Isotopic enrichment offers
potential to 70,000 years.
1 (con't). This indicates a young earth (less than
10,000 years).
Nope. Even if true, it would only indicate a young
atmosphere.
1 (con't). This also nullifies all dates obtained by
C-14 decay.
Using the putative water vapor canopy, most
creationists argue that "pre-flood" C14 dating is bogus
and that "post-flood" dating is legit. You may want to
ask Hovind why they are wrong and he is correct?
1 (con't). As the earth's magnetic field decays, more
cosmic radiation is allowed to penetrate into our
atmosphere. 16 clicks (on a geiger counter) per minute
per gram (16 DPM/Gc) is typical in living objects
today. Plants and animals that lived on the earth a
few thousand years ago would have had much less C-14 in
their body to start with. This would make them appear
to be thousand [sic] of years older than they really
are.
Here again Hovind implicitly uses uniformitarian
reasoning. Scientists know that earth's magnetic field
is decaying. Creationists take this to mean that the
field has decayed linearly from a maximum value at the
beginning. They ignore (suppress) the fact that
periodic polarity reversals reset the field and decay
starts in again. So decay is cyclical, not linear.
There is a cause\effect relationship between
magnetic field intensity and cosmic ray intensity
(latitudinally as well as temporally). Basically, the
weaker the field, the greater the cosmic ray intensity,
thus more C14 in the atmosphere and hence in organisms.
More C14 gives younger dates. The reverse is true for
older dates. I have no idea how the geiger counter
clicks bear on the issue, except perhaps as a
smokescreen.
In C14 dating, organic samples that are "a few
thousand years" old most assuredly do not appear "older
than they really are." Based on dendrochronological
calibration, a post-1500 BC organic sample is actually
_younger_ that its C14 date (up to a century). A pre-
1500 BC sample is actually _older_ than the C14 date
derived from it (up to 800 years older). There is no
doubt about this.
2. Decay rate remains constant. This assumption has
been shown to be in error many times. Several factors
affect the rate of C-14 decay. The 11 year solar sun
spot cycle is one such factor. Since the rate of decay
is not constant, no dates obtained by C-14 can be
trusted.
The decay rate of C14 has to be a constant. No one has
ever shown the assumption to be in error, even using
"sun spots". Ask for the sun spot citations. I know
of none.
However, the constant cannot be deduced from first
principles. It must be measured by experimentation,
and it has been. Experimental error results in various
half-lifes (the exponential decay rate). Libby
obtained a weighted average of 5568 +/- 30 from three
measurements, namely 5580 +/- 45; 5589 +/- 75; 5513 +/-
165. Recent experiments have resulted in a weighted
average of 5730 years, which by convention is used
today. Nothing in these calculations renders the
dating technique untrustworthy.
3. Initial amount of C-14 can be known. This
assumption has been demonstrated to be wrong many
times.
Initial amount is not assumed. Dendrochronological
calibration corrects for variations in initial amounts
of the parent (C14).
3 (con't). Different parts of the same sample often
yield different ratios. Various living samples give
very different ratios.
Though confused, Hovind here uses an argument from
anomaly. The structure of this argument is > there are
exceptions, therefore the technique is bogus. The
premise is true, but the conclusion does not follow.
Different parts of a mollusk shell, for example, yield
varying dates. This is because mollusks ingest C12
mostly from a terrestial environment with much
carbonate, thereby skewing the C14/C12 ratio (isotopic
fractionation). Physicists are well aware of this, and
they figured it out, not creationists. That is why
archaeologists seldom use dates from shell (although
the conchiolin portion of shell is useful). No such
problem exists for charcoal because plants derive most
of their carbon from photosynthesis (atmospheric
carbon).
4. The sample being tested has not been contaminated.
This assumption is very difficult, if not impossible to
prove. Parent or daughter products could have leached
in or out of the sample. Many lab tests have confirmed
that this does happen.
No lab ever assumes a sample is uncontaminated. The
sample is closely examined. If contaminated, various
procedures are available to clean the sample. Rarely
does contamination prevent an accurate assay. When a
C14 date is considered anomalous, it is usually so
because the archaeologist has been careless (e.g.,
misread the stratigraphy).
5. Accurate measurement of C-14 in sample. This is
not reasonable to assume. The amount of C-14 in the
atmosphere today is less than one part per million.
Claiming to be able to measure accurately to 7 decimal
places is not reasonable.
This is the argument from incredulity. It is
meaningless. The fact that Hovind's mind can't
conceive of several more decimal places than usual is
his problem.
6. Shape of the curve of the line is known. This
assumption is not rational. The oldest sample of
independently known age is Hemaka, the Egyptian mummy
from 2700-3100 B.C. To base a graph on such a small
section of the curve is not wise. (Secular writers of
antiquity tend to exaggerate ages so even these dates
are suspect)
Evidently Hovind thinks C14 dates are calibrated on a
sequence (curve) of historical dates. They are not
(though Libby originally tested his method, in part,
with considerable success on historical objects of
known age). They are calibrated from tree ring master
charts (dendrochronology). An annular growth ring of
known age is C14 dated. The discrepancy, if any,
between the known date and the C14 date is noted. Many
comparisons are obtained, and eventually a calibration
curve can be constructed. Actually, the "curve" in
detail is characterized by wiggles, the wiggles
charting short term fluctuations in cosmic ray
intensity, the curve charting the long term average
variation.
Further, Hovind seems to think that his historical
curve is not "long" enough to establish a reliable
"curve". But the length (in years) of a calibration
curve, whether based on historical objects or tree
rings, has nothing to do with reliability. If a
reliable curve spans only 3000 years, it is accurate
for those 3000 years.
In any case, the oldest sample of known age is not
Hemka (not to mention that a 2700-3100 range is not a
calendrical age). The oldest sample of known
calendrical age is an annular tree ring (bristlecone
pine) which is 8681 calendrical years old. The
bristlecone pine sequence is tied to the South German
Oak sequence to obtain a calendrical date of 9209 +/-
10 years ago. Correlation of the tree ring sequences
to adjusted Swedish varve dates provides a tentative
calendrical date useful for C14 calibration at 13,300
years ago.
7. The geologic column is a base to calibrate the C-14
dates. This assumption is not wise.
Here we find that Hovind has no clue about
dendrochronological calibration. Either that, or he
is, as creationists often are, guilty of supression.
Whatever, the geologic column has nothing to do with
C14 dating (although archaeologists use stratigraphy on
a fine scale).
7 (con't). The entire geologic column is based on the
assumption that evolution is true. This fictitious
column (invented in the 1800's to discredit the Bible)
does not exist anywhere in the world except in
textbooks.
Column based on evolution? Exactly the opposite
occurred. The entire geologic column was in place
decades before Darwin published his theory. His theory
provided a satisfactory explanation for the nature of
the column. Prior to that, all manner of non-Darwinian
explanations were advanced, the most popular being
catastrophism.
Many devout and pious Christians (e.g., John Ray,
Charles Lyell, William Smith, James Hutton, Georges
Cuvier, Nicholas Steno, etc.) helped figure out the
geological column. They certainly were not trying to
discredit the Bible. They saw in nature another record
of their God's handiwork, and they set out to read that
record.
The geologic column, or timescale, is constructed
from regional and local sequences worldwide. Hovind's
implicit claim that the geologic column must exist
outside of textbooks in order to accurately represent
earth history is entirely his. No geologist has ever
made that claim (even John Morris) - or ever will.
7 (con't). Poly-strata fossils, missing layers, layers
out of order, misplaced fossils, and layers in reverse
order all invalidate the geologic column. (Watch
seminar tapes #4-6 by Dr. Kent Hovind for more
information.)
Henry Morris also uses the "poly-strata fossil"
argument. Sponges, for example, exist today and they
are found as fossils in deep time. Therefore, fossils
cannot be used to date (relatively) strata. This
completely ignores at least two factors, 1) experts can
and do detect variation in what look to be the same
fossils distributed across multi-strata, and 2) the
fact of index fossils - organisms of limited temporal
duration and wide distribution.
Missing layers, inversions, etc. are understood and
recognizable by geologists, and have been for nearly
two centuries. Phenomena not presently understood are
not understood. Nothing more. The inability to
understand does not invalidate earth history as known.
Even more to the point, it doesn't prove Hovind's world
view.
So far I am not inclined to watch seminar tapes #4
thru #6 by Dr. Kent Hovind. I think I'd rather go down
to the service station and watch the boys change tires.
7 (con't). _The assumed age of the sample will dictate
which dating method is used since each will give a very
different result._
Decidedly wrong. The nature of the material to be
dated usually determines the method used. For example,
organic remains can only be reliably dated by C14.
Potassium argon dating is only useful on volcanic
rocks. A given rock may be dated by several techniques
(e.g., uranium series, strontium/thorium, KAr), each of
which is independent of the other. In such cases, the
independent techniques regularly yield statistically
consistent dates.
Who, pray tell, is Kent Hovind, and what does the Dr.
before his name mean?
Rich Fox, Anthro, Usouthdakota
E-Mail Fredric L. Rice / The Skeptic Tank