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Program Review:
Jenn knows fossils. In addition to her paleontology and geology studies at the
University of Delaware, Jenn has worked for three summers at the Philadelphia Academy of Natural Sciences, has participated
in several dinosaur digs in both the eastern and western U. S., and still finds time to
partake in fossil field trips!
At tonight's meeting, she walked us through fossil preparation and conservation
techniques. Her largest example was "Dinny the Dino",
a suspected Titanosaur, from the Delaware Geological
Survey and University of Delaware collection
archives.
Jenn filled us in on the unfolding saga of the best identification so far of this
mystery titan. From x-ray analysis to a pending palynology study, she chronicled this
dino's history using these and other id techniques. In fact, Jenn will be presenting
in October her findings to the Academy.
Her slide show depicted her lab and some of the tools used, as well as fossils
currently being prepared for study in her course. Jenn outlined the field procedure
for collecting large dino bones via the plaster-of-paris jacket and aluminum foil method.
And, she noted the finding and preservation of the skull and dentition is key to
identification, especially against other related dinosaurs.
She brought in other vertebrate fossil examples to show, as well as a section of a
"Dinny" bone. In narrowing the classification of Dinny, Jenn pointed out
that the vessicles (circulatory system channels) and greater bone density point to Dinny
as being an herbivore. Without a skull, further study will rely on a bone and matrix
fossil pollen study to tune in on the geological time-frame in which Dinny lived.
Jenn described to us how she and her six students approach problems created by
long-term archival storage and perhaps a century-old field jacket removal. Armed
with razor knifes, dental picks, and a shared airscribe tool, each painstakingly removes
practice bits, before they can attempt conservation of Dinny.
The airscribe is like a mini jack-hammer, which makes matrix and jacket removal faster.
Some clay nodules had been removed from Dinny already, which have been submitted
for study, first to her boss, Peter McGloughlin, then to scientists at the Smithsonian. The remaining matrix is mostly silica
(from sandstone), which is difficult to remove.
Until her students have training enough to work on Dinny, Jenn has them hone their
skills on new finds from the Inversand Mine in Sewell,
New Jersey, a famous K-T boundary
dig site. Students prepare these fossil finds free-of-charge for the Academy.
Bone cross-sections are next. From observation and comparison studies of the
uncut bone fragments, she has determined that compact bone, girth, and age point to a Jurassic plant
eater from the Morrison
formation. Likely, either a diplodicus
or titanosaur
as her tentative id, the intact radius
and ulna suggest the latter.
Her lab technique section covered everything from the use of glues and stabilizers for
bone, such as Paleo-Bond, and Paleo-Poxy for infilling
missing fragments, to digging, jacketing, and support of lab specimens on the tables with
sandbags. She noted that all assembly work must be reversible to support future
study.
Jenn also offered some progress on her senior thesis project on the paleopathology of Allosaurus. Coincidentally, the
scientific community has just celebrated in 2005 the centennial of the official naming of
her project dinosaur.
During her presentation, many fossil enthusiasts asked a lot of dino questions.
The depth and detail her work continues to impress us. We wish you well in
your future fieldwork and museum studies. Thanks, Jenn.
[Ken Casey]
Links
University of Delaware Dept. of
Geological Sciences
Dinobase at
the University of Bristol
Stuart Plotkin's Fossil Prep Lab
(Hobbyist Site)
Airscribe
Tool at Grobet USA
Airscribe Tool at PaleoTools
PaleoWorld
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