[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Free Theses



OK, so that's not a movie title...but it's something NOT to spoonerize!
Anyway, here's a couple available free on-line (though in TIFF
format...Acrobat can convert 'em to PDFs easily enough, though; thanks to
Ken C. for finding these!):



Christians, J.P. 1992. Taphonomy and Sedimentology of the Mason Dinosaur
Quarry, Hell Creek Formation (Upper Cretaceous), South Dakota. M.S thesis
thesis/dissertation, University of Wisconsin, Madison, 91 pp.
(http://minds.wisconsin.edu/handle/1793/18663)

ABSTRACT: Excavation of the Mason Dinosaur Quarry (Ziebach Co., South
Dakota) has yielded thousands of bones of the hadrosaur Edmontosaurus
annectens. Results of taphonomic analysis of the deposit reveal a
pauci-specific, parautochthonous assemblage of freshwater and terrestrial
fauna dominated by disarticulated bones of Edmontosaurus sp. Size-frequency
data and abundant evidence of incipient weathering stages illustrate mass
death of a group of Edmontosaurus sp. containing hundreds - possibly
thousands - of individuals. The size range of individuals represents ages
from subadult through aged adult, with prime adults being most common. This
age-class structure could constitute a non-breeding or migrating herd.
     Sedimentologic analysis indicates that the hadrosaur remains
accumulated on the floodplain of a meandering fluvial system. Subsequent
transport and redeposition of the remains occurred during one or two
episodes of rapid mud sedimentation, probably as crevasse splay or overbank
flooding. Abundant evidence of incipient abrasion stages indicates
relatively little transport. Rapid deposition is indicated by 1) massive
bedding, 2) disrupted bedding caused by dewatering of saturated mud 3) crude
grading and relatively poor sorting of the bone assemblage, and 4) the
presence of steeply plunging bones.




Ott, C.J. 2002. Leptoceratops (Dinosauria: Ornithischia) from the Hell Creek
Formation (Cretaceous; Maastrichtian) of Eastern Montana. M.S thesis
thesis/dissertation, University of Wisconsin, Madison, 121 pp.
(http://minds.wisconsin.edu/handle/1793/7090)

ABSTRACT: Two new dinosaur specimens were recovered from the Hell Creek
Formation of Carter County, Montana, by field crews from the University of
Wisconsin-Madison Geology Museum. The first specimen is a partial skull,
consisting of the occipital region, a complete braincase, a parietal frill,
a post orbital, and the paired frontals. The skull is identified as basal
neoceratopsian, based on the exclusion of the basioccipital from the border
of the foramen magnum by the exoccipitals; the inclusion of the
supraoccipital in the dorsal border of the foramen magnum; the expansion of
the parietal caudo-dorsally to form a frill; dorsal sagittal spine on
parietal; a horn-less postorbital, with no development of sinus cavities
internally; lack of folding of the frontals to form frontal sinus cavities;
presence of three nerve foramina in the base of the exoccipital; and the
paroccipital process composed primarily of the exoccipital. The skull is
further referred to Leptoceratops gracilis based on constriction of the neck
of the occipital condyle; midline depression below the occipital condyle;
smooth, rounded basioccipital tubera; straight basipterygoid processes; lack
of extension of pterygoid buttress below the ventral margin of the
exoccipital; and a solid parietal frill lacking any fenestrae. Newly
described features of this skull include disarticulated prootics; a
disarticulated supraoccipital showing foramina for the anterior and
posterior semicircular canals of the middle ear; limited extent of the
opisthotic; and a completely disarticulated braincase with cranial nerve
foramina exposed.
     The second specimen is a partially worn maxillary tooth, which includes
a root. It is identified as a basal neoceratopsian based on the single root;
enamel on only one face of the tooth crown; and ceratopsian features of
ridges on the enameled surface. It is referred to Leptoceratops gracilis
based on the presence of a cingulum on the base of the tooth, and the
diagnostic notched tooth wear pattern
     The two specimens of Leptoceratops gracilis described are the first
representatives of this species in the Hell Creek Formation, and extend the
known range of this dinosaur nearly 500 km to the east. The two new
specimens were discovered in channel sandstone deposits in a coastal lowland
environment. The nine specimens previously known were recovered from
deposits that have been interpreted as upland environments. The presence of
Leptoceratops gracilis was previously used to delineate biogeographic zones
in the latest Cretaceous terrestrial deposits in the Western Interior of
North America. Discovery of these two specimens necessitates a revision of
the biogeographic zones, and a redefinition of the Triceratops-Edmontosaurus
faunal assemblage. These two specimens may reduce the suitability of
Leptoceratops for defining faunal zones in the latest Cretaceous Period.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Jerry D. Harris
Director of Paleontology
Dixie State College
Science Building
225 South 700 East
St. George, UT  84770   USA
Phone: (435) 652-7758
Fax: (435) 656-4022
E-mail: jharris@dixie.edu
 and     dinogami@gmail.com
http://cactus.dixie.edu/jharris/

"There's a saying that goes 'people who live in glass houses shouldn't throw
stones'... OK. How about...NOBODY should throw stones. That's crappy
behavior! My policy is 'no stone-throwing regardless of housing situation.'
There's an exception, though. If you're TRAPPED in a glass house...and you
have a stone, then throw it! What are you, an idiot? It's really 'ONLY
people in glass houses should throw stones'... provided they're trapped, in
a house... with a stone. It's a little longer, but you know..."
                                 --- Demetri Martin