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Re: Burnt fossil bones
This is an abstract from a poster presented at the Dinosaur Park
Symposium (September 2005). Hope it helps.
Paleowildfire characteristics and behavior: diagenetic changes
occurring in vascular bone during cremation by wildfire reveal ancient
Marilyn D. Wegweiser
Paleowildfire behavior can be ascertained by examining changes that
occur in vascular bone during cremation. Vascular bone of ancient
animals that were alive or recently dead during cremation exhibits
color and mineralogical changes consistent with those changes that
occur in modern vascular bone. Burned bone becomes inert, remaining
unchanged during fossilization processes, and thus provides a record of
ancient wildfire behavior. Morphological changes in bone indicate the
potential range of fire behavior, from a ground or brush fire to a
crowning fire. In some instances, extreme fire behavior can be implied
from the morphopmetric changes induced in bone. Because the
paleolatitude of Wyoming¡¯s Big Horn Basin in the Late Cretaceous
(70-66.5 Ma) was close to present day latitude , it is reasonable to
suspect this region was equally vulnerable to ancient Pacific Ocean and
Interior Seaway currents influencing the climate resulting in seasonal
wildfires. Fossil evidence of paleowildfires from northwestern Wyoming
led me to compare modern cremated vascular bone with dinosaur bone
found associated with fossilized charcoal and bu8rned wood bearing
fire scars. Late Cretaceous dinosaur bone from the Meeteetse Formation
of Wyoming exhibits morphological changes that are similar to those
found in modern vascular bone that had undergone changes during
cremation. The nature of the changes, including crescentic fractures,
reorganization of osteocytes, and glassification of CaPO4, suggests a
ground fire of long duration with sustained temperatures in the range
of 650¢ªC to 800¢ªC, or a crowning fire with temperatures in excess of
1200¢ªC. Identification of sedimentary layers containing paleowildfires
provides a powerful tool for better understanding cyclicity of wildfire
in association with other regional climatic signals or patterns,
provides clues to the ecology of ancient trophic environments, and
provides a possible chronostratigraphic tool for regional correlation.
Quoting Phillip Bigelow <firstname.lastname@example.org>:
Or maybe: "Bones that appear to have been burnt before fossilization".
Does anyone have any refs. on this? Especially any refs on the
petrography of the fossil bone.
During this afternoon's chicken BBQ, I got into a discussion (actually a
polite argument) with a professional forester on the subject of how one
would determine if fossilized dinosaur bones show a "fingerprint" of
having been burned by fire prior to burial.
I figured that taphonomy gurus Behrensmeyer or Shipman would have had
something to say on this subject, but so far, I'm pullin' up nuthin'.
And has anyone made a chicken marinade of vodka, black peppercorns
garlic, and maraschino cherry juice? If not, then I hereby dub the
marinade "Phil's Chicken Soused".