Steve wrote:
>I realize that hauling out examples of "60-million-year-old"
>non-petrified wood fossils will not convince any YEC advocates of a
>great age to the earth since it begs the question. Nevertheless, this
>last site greatly impressed upon me the enormous variability of
>petrifaction rates. IMO, the degree of petrifaction, BY ITSELF, is
>neither a good argument for nor against the age of the earth - it is
>irrelevant. Unless we have evidence to inform us of the route and
>process by which petrifaction took place, we can say very little about
>how long it took to get to San Francisco. I haven't made it to San
>Francisco yet -- in either sense of the metaphor.
You are quite right, fossilization rates are irrelevant to the issue of the
age of the Earth. Several types of fossilization can indeed occur quite
rapidly. Mollusk shells can begin the process of pyritization under
appropriate conditions while the animal is still living. Phosphatization
is renowned for its ability to preserve soft tissues. Phsophate can
preserve individual cellular structures, thus occuring before any
significant decomposition. Precipitation of calcium carbonate is catalyzed
by the decomposition of organic matter resulting in the occurrence of fish
and many other fossils encased within calcium carbonate concretions.
Silica is also very good at precipitating around algal cells such as in the
famous fossils of Precambrian procaryotes in cherts.
Keith
Keith B. Miller
Department of Geology
Kansas State University
Manhattan, KS 66506
kbmill@ksu.ksu.edu
http://www-personal.ksu.edu/~kbmill/
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