A physicist's discovery begins an extraordinary odyssey
pride and prejudice in the scientific world.
By Dennis Crews
< Prev 1
... Next >
In 1976 Robert Gentry published the results of a new round
of research that drew unprecedented attention to the implications
of his earlier work. He had long puzzled over the possibility
of secondary polonium halos. If any existed, it seemed they would
be found in a place where uranium was abundant, and in a substance
whose internal structure would permit rapid infiltration and
transport of a uranium-rich solution and which contained microscopic
capture sites for polonium atoms to accumulate.
No material seemed more ideally suited to the special requirements
of secondary halo formation than wood. Gentry was reminded of
some specimens of radioactive wood he had heard of a few years
earlier. A bit of sleuthing revealed that partially coalified
pieces of wood, some as large as logs, had been found in several
uranium mines in the western U.S. Gentry was finally able to
obtain some samples of the wood and began studying them.
Microscopic examination of prepared specimens revealed an
abundance of uranium halos in the wood. The evidence suggested
that prior to coalification the wood had been in a water-softened
condition, permitting the infiltration of water-borne uranium.
Uranium atoms had accumulated in capture sites scattered through
the wood and secondary halos had formed around the capture sites.
Since enough uranium had been deposited in the wood to create
halos, Gentry thought, perhaps there would be secondary polonium
halos as well.
Gentry's hunch paid off. After painstaking examination, certain
of the coalified wood samples revealed polonium halos in even
greater numbers than uranium halos. Several unusual facts seemed
to stand out, however. First, every polonium halo in the wood
was from the isotope 210Po—not a single halo could be found
from 214Po or 218Po. Suddenly it made sense. The 210Po isotope
had a half-life of 138 days—long enough to be filtered out of
the uranium solution and accumulate in the capture sites. The
two other polonium isotopes, with half-lives of minutes or less,
simply decayed away before they could accumulate in the capture
This was a crucial discovery. Natural circumstances could
hardly be more favorable for the formation of secondary halos
than they were in the wood specimens. Uranium was abundant, and
the porosity of wood afforded ideal opportunity for its infiltration.
Even under such optimum conditions, however, only one halo type
had been able to form. In contrast, all three halo types were
profusely scattered through solid rock—where no significant amounts
of uranium existed and where permeability was virtually nil.
This was most compelling evidence that the halos in the rock
could not be of secondary origin.
The second oddity was that most of the secondary polonium
halos found in the wood were not perfectly round, but elliptical.
This indicated that the halos were formed while the wood was
still in a soft condition, before it was compressed by the weight
of overlying sediment. After careful analysis it was found that
the elliptical polonium halos in wood specimens taken from three
different geological strata—Triassic, Jurassic and Eocene—were
virtually identical. Evidence suggested that all the specimens
had been infiltrated with the same uranium-bearing solution during
a single event.
These findings had disturbing implications for conventional
geochronology. The Triassic, Jurassic and Eocene formations are
thought by most scientists to have been deposited tens of millions
of years apart, but the elliptical halos showed that the wood
specimens from each strata had been in a soft, porous condition,
uncompressed by overlying sediment, and equally exposed to the
elements at the time of infiltration. The simplest scenario to
account for their infiltration would be a major flood which uprooted
trees, soaking them in water which had absorbed large amounts
of uranium from nearby ground deposits, and finally compressing
them between layers of sediment. A flood like the one described
in the biblical book of Genesis would have done just that.
During his investigation Gentry was puzzled to discover a
small number of dual polonium halos in a few of the specimens.
In these an elliptical halo was superimposed with a circular
one, surrounding the same center. How did the dual halos form?
The most likely cause, Gentry realized, was a second infiltration
of a uranium-bearing solution occurring soon after the first,
while the wood was still soft and porous. The centers of the
polonium halos caused by the first infiltration would have an
affinity for a uranium daughter, 210Pb, introduced in the second
infiltration. This element decays with a half-life of 22 years
to 210Po, which in turn would form a second halo.
If the wood remained intact for the duration, both halos would
overlap perfectly and appear as one. If the wood were crushed
or deformed after 22 years then the overlapping halos would be
compressed into an elliptical shape together. But if deformation
of the wood happened within just a few years of the second infiltration,
then only the first halo, which had already formed, would be
compressed. In 22 years the second halo would form a perfect
circle around the flattened first halo.
Here was the answer to a question Gentry had not even asked
yet: how much time had passed between the formation of the halos
and compression of the wood? Geochronology based upon the uniformitarian
principle, encompassing tens and even hundreds of millions of
years, would be utterly confounded by the brevity of time suggested
by the data at hand. The evidence was compelling that only a
few years at most had elapsed between the first infiltration
of the wood with uranium and the time when it was compressed
by overlying sediment. Taken all together, the facts supported
no other geological model as strongly as the Genesis flood account.
After amassing this large body of new data Gentry and several
colleagues summarized their findings in a collaborative report
published by Science.18 The published data showed a clear distinction
between the secondary halo type found in coalified wood and the
multiple, primordial halo types found in granite. In careful
but unmistakable language the report questioned conventional
geologic age dating as well as the uniformitarian interpretation
of the entire geologic column. It was a challenge that seemed
to demand a response from the scientific community.
18 Robert V. Gentry et al, 1976. "Radiohalos in Coalified Wood: New Evidence Relating to the Time of Uranium Introduction and Coalification." Science, vol. 194, p. 315.
For readers interested in a more comprehensive treatment of this story, Robert Gentry's book, Creation's Tiny Mystery, is available for $18 (U.S.) + S/H.
To order our book and/or videos,
Call Us at (800) 467-6380, or use our order form.
< Prev 1
... Next >