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Re: Exact length of Sue



I would guess you can get a copy somehow thru the AMNH library if you access to that. Or thru DML.

Dan

On 4/21/2015 8:10 PM, Victoria & Jerrold Alpern wrote:
Dan

Thanks! Schopf’s paper is behind a paywall, unfortunately,: 
http://www.sciencedirect.com/science/article/pii/0034666775900056

All best,

Jerry

On Apr 21, 2015, at 9:56 PM, Dan Chure <danchure@easilink.com> wrote:

Back in the late 1970s USGS personnel did a chemical analysis of dinosaur bone samples 
from the Carnegie quarry face and they were about 85% identical BY VOLUME (not weight) 
with the composition of bone when the animal was alive. That seems to be about standard 
fare, maybe even less depending on the post mortem history of the bone.  Schopf did a 
paper in the late? 1970s entitled "Modes of fossilization" in Paleo3 (as I 
recall) which was an excellent review of the subject. Maybe there have been better ones 
since then. Sorry I can't provide a better citation at the moment but I don't have it at 
hand.  I know I don't have a pdf.

Dan

On 4/21/2015 7:24 PM, tholtz wrote:
That is rather out-of-date thinking, actually. Most fossil bone is 
permineralized: the original bony mineral (hydroxylapatite) and even collagen 
is still present, but the pore space is filled to some degree with minerals 
from ground water. Some fossil bone is unaltered: nothing added, nothing lost 
except the greasy organics. Actual honest-to-goodness replacement is very rare 
for fossil bone, although more common in fossils of some other groups.

So the real bone is there. But there is other stuff added.

On 2015-04-21 21:13, Victoria & Jerrold Alpern wrote:
Dan,

What I meant was that the organic bones that supported the dinosaur in
life were replaced underground by minerals that formed an exact cast
of the originals. These are precise enough replicas that they carry
the information, including isotope signatures, LAGs, etc. that provide
the raw material of paleohistology. If I am wrong, or have stated the
process incorrectly, please tell me. Many who come to AMNH are
interested in dinosaurs but have never considered the process of
fossilization.  My only wish is to convey accurate information to AMNH
visitors.

Thank you!

Jerry Alpern

On Apr 21, 2015, at 8:51 PM, Dan Chure <danchure@easilink.com> wrote:

I don't think this is quite true: "most fossils are themselves casts of the original 
bones." If it was, there would be no discipline of paleohistology.

Dan


On 4/21/2015 10:37 AM, Victoria & Jerrold Alpern wrote:
Thanks! I had thought both legs of AMNH 5027 were replicas of CM 9380, which I assume is the 
holotype we sold to the Carnegie in the 1940s. Now I’m going to have to revise what I tell 
visitors!  They often assume that what they see are “fakes”, by which they mean 
copies. They are happy to learn that most of our 4th Floor fossils are genuine, although I always 
add that most fossils are themselves casts of the original bones.

Jerry Alpern