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Re: first message



Tony inquired:
----- Original Message -----
From: "TONY" <tony@razsemi.com>
To: <dinosaur@usc.edu>

    "...I visited the some website last week hosted by an
expedition heading towards the Gobi desert seeking fossils.
In one article titled "How fossils go from bone to stone", the following
part struck me:"

    [Tony's quote of the web article] "A fine fossil is a freak of nature.
The dead animal first must avoid
scavengers, floods and other scattering forces..."

    I shall not belabor the fact, but dead animals "avoid" nothing! :)  That
is just careless writing.

    "...Then it must be buried in something that's neither too soggy..."

    This is simply wrong!  Chemistry may be the most important factor, for
we must not forget that some of the best-preserved Mesozoic animals --
non-avian dinosaurs included -- were deposited in a fresh-water lake(s?) in
the Liaoning Province of north-eastern China, which was about as wet as it
gets.  There, the preservation seems to have been -- at least in large
part -- fascilitated by the chemical content of VOLCANIC ASH, which fell
into the water.

"... to nor completely dry,..."

    Again, not entirely so.  Much of the wonderful fresh-looking bones of
dinosaurs and other animals which one finds buried in sands of the Gobi
desert, for example, are from animals buried in sandstorms, whereupon, I
suspect, SLOW dessication accompanied only by occassional silica infusion
from rain that has passed through the sand, above, carrying molecular
silicon into bone pores opened by dessication, has caused the beautiful,
fresh-looking preservation.

"..in a climate that won't subject it to swelling/shrinking cycles that will
splinter it..."

    Certainly.

 [Continuing, I'm not sure if this is Tony speaking or the web page, but for
a paleontologist the error would be inescusable.] "(THE CITIZENS OF POMPEII
WERE ROCK-SOLID IN UNDER 2000 YEARS..."

    This is nothing short of pure, unadultrerated error!  It is absolutely
WRONG!  No, what one sees in the displays of Pompeii are simply PLASTER
CASTS made by filling CAVITIES WHERE BODIES OF PEOPLE AND PETS HAD DIED AND
DISINTEGRATED in the volcanic ash that has consolidated since the fateful
eruption, and then removing (cutting apart) the natural volcanic 'mold'
surrounding each.  The artificial 'fossils' of people and pets that result
may look (to the careless eye) 'petrified' because some volcanic ask has
clung to the plaster, but this is absolutely not the case.  I have been to
Pompeii and heard and seen this carefully explained, but in some quarters
the myth of fossilized Pomeiian bodies lives on.

    "...YET SOME 65 MILLION-YEAR-OLD-DINOSAUR BONES ARE STILL NOT COMPLETELY
STONE.)"

    Of course. NO silicified bones are ever completely stone.  For years now
it has been known that much of the hydroxy-apatite (the major consitiuent of
bone) remains in the fossil, saturated intersticially with silica.  Thus,
the deceptively fresh look of some fossilized bones.

    "Such a huge difference in timing to achieve the same phenomenon looks
impossible to me...."

    Of course, when one mistakenly compares 'peaches' with 'oranges'!

    "...Are we that sure these fossils are actually 65 million years old?
How accurate is the dating process?"

    Many are vastly older than that, and there are diverse methods of
dating, the most accurate of which is isotopic.  Interestingly, comparing
DIFFERENT pairs of isotopic abundances in a given fossil yeild beautifully
coincident dating, considering we are looking at a scale of, in some cases,
hundreds of millions of years.


    My two cents worth,

    Ray Stanford

    "With patience, beliefs yield to discovery."