New Papers of Solace

["Jerry D. Harris" <jharris@dixie.edu>]

Not that I'm a Bond fan or anything...  Anyway, thanks to RI, JK, and SP for
many of these, and my apologies if any are duplicates from other posts...



Padian, K. 2008. The Early Jurassic pterosaur Dorygnathus banthensis
(Theodori, 1830). Special Papers in Palaeontology 80:1-64.


Padian, K. 2008. The Early Jurassic pterosaur Campylognathoides Strand,
1928. Special Papers in Palaeontology 80:65-107.



Therrien, F., Zelenitsky, D.K., and Weishampel, D.B. 2008.
Palaeoenvironmental reconstruction of the Late Cretaceous Sânpetru Formation
(Haţeg Basin, Romania) using paleosols and implications for the
"disappearance" of dinosaurs. Palaeogeography, Palaeoclimatology,
Palaeoecology. doi: 10.1016/j.palaeo.2008.10.023.

ABSTRACT: Paleosols of the Late Cretaceous Sânpetru Formation (Haţeg Basin,
Romania) are the subject of macroscopic, microscopic, and geochemical
investigation in order to reconstruct the palaeoenvironmental and
palaeoclimatic conditions in which dinosaurs lived. Study of overbank
deposits present in an 860-m-thick stratigraphic interval of the Sânpetru
Formation exposed along the Sibişel Valley reveals the presence of one
facies and five different pedotypes: 1) finely laminated gray-green
mudstones and siltstones interpreted as pond deposits; 2) bioturbated
graygreen mudstones lacking macroscopic pedogenic features, interpreted as
very poorly-developed hydromorphic paleosols; 3) bioturbated gray-green
mudstones containing carbonate concretions, interpreted as poorly-developed
hydromorphic paleosols; 4) mottled gray-green mudstones containing carbonate
concretions and limited illuvial clay accumulation, interpreted as
moderately-developed paleosols characterized by a high but fluctuating
watertable; 5) bioturbated brown-red mudstones lacking macroscopic pedogenic
features other than the
occasional mottles, interpreted as poorly-developed paleosols that formed on
the higher and better-drained floodplains, and; 6) bioturbated brown-red
mudstones containing carbonate nodules, interpreted as moderately-developed
calcareous paleosols that formed on distal floodplain settings. Although
limited exposure prevents the documentation of lateral relationships of
pedotypes, the presence of paleosol profiles that display characteristics of
two different pedotypes suggests that they represent a lateral continuum on
the landscape related to local differences in hydrology and relief (i.e.,
catena). The pedotype assemblage reveals that the Sânpetru landscape was a
mosaic of wetlands, seasonal wetlands, and better-drained floodplain
habitats, similar to the present-day Indogangetic Plains. Pedogenic features
and  aleosol geochemistry indicate that the Maastrichtian climate of Romania
was subhumid (< 1000 mm rain/year) and characterized by strongly seasonal
precipitation.
     The distribution of pedotypes through the Sânpetru Formation reveals
small- and large-scale palaeoenvironmental changes associated with the
shifting of a complex mosaic of wet and dry habitats in response to shifts
in river position on the alluvial plain. However, a major
palaeoenvironmental change occurs in the upper Sânpetru Formation, where the
region was transformed into extensive wetlands. Such dramatic changes
coincide with river competence increase, change in palaeocurrent directions,
and dearth of macrovertebrate remains, which had been previously
misinterpreted as evidence for the disappearance of dinosaurs at the
Cretaceous-Tertiary boundary. These palaeoenvironmental changes, induced by
tectonism, are responsible for the shift from preservation of macrofossils
concentrated by hydraulic processes into conspicuous lenticular bonebeds in
the lower Sânpetru Formation to preservation of microfossil, and more rarely
macrofossil, remains in hydromorphic calcareous paleosols in the upper
Sânpetru Formation. The consequences of palaeoenvironmental changes on
vertebrate preservation mode must be considered in the search for fossils
and interpretation of the fossil record.




Kjemperud, A.V., Schomacker, E.R., and Cross, T.A. 2008. Architecture and
stratigraphy of alluvial deposits, Morrison Formation (Upper Jurassic),
Utah. AAPG Bulletin 92(8):1055-1076. doi: 10.1306/03250807115.

ABSTRACT: This article presents a unique cross section of a 13.5-km
(8.3-mi)-long by 150-m (492-ft)-thick stratigraphic interval containing
braided stream and associated flood-plain deposits. The cross section is
oriented approximately parallel to depositional strike. This cross section
is a resource for geoscientists and engineers interested in the measurements
of stratigraphic architectural elements, such as dimensions and continuity
of facies tracts and facies associations, stratigraphic and geographic
changes in sandstone/mudstone proportions (net to gross), and frequency and
cause of vertical fluid communication between superposed reservoirs. 
     In addition to presenting this rich data resource, observed and
documented stratigraphic relationships add to our conceptual understanding
of certain attributes of the stratigraphic process-response system. For
example, we show that, like meandering rivers, aggradational braided river
systems also build levees and alluvial ridges, providing the supra-elevation
above the adjacent floodplain to create extensive crevasse splay and channel
complexes. We show that superposed channel sandstone reservoirs may be
brought into physical contact not only by the erosion of an upper sand into
a lower sand but also by the vertical aggradation of the lower sandstone,
producing a pyramid on which a younger sandstone is deposited. 
     Four stratigraphic cycles of increasing and decreasing
accommodation/sediment supply (A/S) regimes are identified. These cycles are
recognized from systematic vertical changes in stratigraphic and
sedimentologic attributes. At the largest scale, there is a progressive
downhill shift in facies tracts recording a basinward stepping of the four
stratigraphic cycles. At the intermediate scale, there is a systematic
change in channel types, from laterally amalgamated braided channels, to
vertically building braided channels, to steer-head distributary channels
encased within lacustrine-dominated fines. At the smallest scale, systematic
and repeated vertical successions of facies occur within the three types of
channel belts. These systematic changes are related to progressive changes
in the A/S regime that occur during superimposed stratigraphic base-level
cycles of three different scales.




Butler, R.J., and Barrett, P.M. 2008. Palaeoenvironmental controls on the
distribution of Cretaceous herbivorous dinosaurs. Naturwissenschaften
95(11):1027-1032. doi: 10.1007/s00114-008-0417-5.

ABSTRACT: Previous attempts to determine palaeoenvironmental preferences in
dinosaurs have generally been qualitative assessments based upon data from
restricted geographical areas. Here, we use a global database of Cretaceous
herbivorous dinosaurs to identify significant associations between clades
and broad palaeoenvironmental categories ('terrestrial', 'coastal',
'marine'). Nodosaurid ankylosaurs and hadrosaurids show significant positive
associations with marine sediments, while marginocephalians (Ceratopsia,
Pachycephalosauria), saurischians (herbivorous theropods, Sauropoda) and
ankylosaurid ankylosaurs are significantly positively associated with
terrestrial sediments. These results provide quantitative support for the
hypothesis that some clades (Nodosauridae, Hadrosauridae) were more abundant
in coastal and/or fluvial environments, while others (e.g. Marginocephalia,
Ankylosauridae) preferentially inhabited more distal environments.




Rauhut, O.W.M., and López-Arbarello, A. 2008. Considerations on the age of
the Tiouaren Formation (Iullemmeden Basin, Niger, Africa): implications for
Gondwanan Mesozoic terrestrial vertebrate faunas. Palaeogeography,
Palaeoclimatology, Palaeoecology. doi: 10.1016/j.palaeo.2008.10.019.

ABSTRACT: Pre-Aptian mid-Mesozoic terrestrial vertebrates from the African
continent are still very poorly known. In Niger, the Tiouaren Formation in
the Iullemmeden Basin has yielded dinosaur and other vertebrate remains, and
this unit has been dated as Early Cretaceous, most probably pre-Aptian, on
the basis of its fish fauna and gelogical relations to other units in the
basin. A review of the fish fauna and invertebrates from this formation does
not provide any evidence for such an age, and the geological relations only
help to constrain the upper limit for the age of the formation (Aptian). In
contrast, the described dinosaur taxa are phylogenetically nested with late
Middle Jurassic to Early Late Jurassic taxa from other localities, and thus
indicate a pre-Kimmeridgian, probably late Middle Jurassic age for the
Tiouaren Formation. Under the assumption of such an age, the dinosaur fauna
of this formation provides new insights into dinosaur faunal provincialism
during the latest Middle Jurassic. Northern Gondwanan faunas of that time
seem to have been different from southern Gondwanan faunas, and show closer
affinities to Eurasian faunas than to the latter. A possible explanation for
this might be a climatically controlled geographic barrier due to pronounced
arid conditions and thus desert environments in central Gondwana during this
time.




Dalla Vecchia, F.M. 2008. The impact of dinosaur palaeoichnology in
palaeoenvironmental and palaeogeographic reconstructions: the case of the
Periadriatic carbonate platforms. Oryctos 8:89-106.

ABSTRACT: Knowledge of dinosaur footprints has greatly changed how
scientists reconstruct the palaeoenvironment and palaeogeography of the
Mesozoic carbonate platforms of the Periadriatic area (Italy, Slovenia and
Croatia). Geologists considered those carbonate platforms as shallow marine,
intraoceanic banks (i.e., surrounded by the Tethys Ocean) during Cretaceous
times. The discovery in the last 20 years of dinosaur fossils, mainly
footprints, in many places and at different stratigraphic levels has
demonstrated that the "shallow seas" were repeatedly or continuously
populated by large terrestrial animals. Thus, the reconstructions of those
carbonate platforms as a sort of Mesozoic "Bahamas Banks" was incorrect. The
new record allows also testing for congruence with palaeoenvironmental and
palaeogeographic reconstructions. Areas where dinosaur fossils have been
found are always considered as "shallow marine" in those reconstructions,
very far away from continental areas during the Late Triassic and earliest
Jurassic and surrounded by deep marine basins during Late Jurassic and
Cretaceous times. The results of this research are a first step toward the
understanding of those dinosaurs living "at the border", but are obviously
preliminary and subject to confirmation or confutation with increased fossil
sampling. The ichnological sample and the palaeogeographic reconstructions
can also stimulate some reflections about the biology of the extinct
dinosaurian clades and give some suggestions for the development of future
research.




Lopatin, A.V., and Agadjanian, A.K. 2008. A tritylodont (Tritylodontidae,
Synapsida) from the Mesozoic of Yakutia. Doklady Biological Sciences
419(1):107-110. doi: 10.1134/S0012496608020117.

ABSTRACT: Tritylodonts are an advanced cynodont group similar in morphology
to early mammals, but specialized too profoundly to phytophagy to bear
direct relation to the origin of Mammalia. The temporary evolutionary
success of this group is supported by the fact that they were the latest
cynodont group in the paleontological record, which survived the Jurassic
Period. The latest genus of Tritylodontidae is Xenocretosuchus from the
Lower Cretaceous of the Kemerovo oblast and Krasnoyarsk krai. The present
study describes a new species of Xenocretosuchus from the Late Mesozoic
Teete locality in the Vilyui River basin (Yakutia), one of the northernmost
dinosaur localities of the world. The material examined is housed at the
Paleontological Institute of the Russian Academy of Sciences, Moscow (PIN).
Dental remains of the type species X. sibiricus from the Shestakovo 1
locality (Kemerovo oblast, Lower Cretaceous) are used for comparison,
including the holotype and paratypes from the collection of the PIN and new
undescribed material housed at the Paleontological Museum of Tomsk State
University (PM TGU).





Lopatin, A.V., and Averianov, A.O. 2007. The earliest Asiatic
pretribosphenic mammal (Cladotheria, Amphitheriidae) from the Middle
Jurassic of Siberia. Doklady Biological Sciences 417(1):432-434. doi:
10.1134/S0012496607060063.

ABSTRACT: A unique recent event in paleomammalogy was the discovery in 2000
of a Middle Jurassic mammal assemblage in the upper part of the Itat
Formation of the Berezovsk quarry, southern Krasnoyarsk krai. This fauna
provides an insight into an early stage of the development of the class
Mammalia in Russia and contains at least two docodont taxa (Itatodon
tatarinovi Lopatin et Averianov, 2005 and Docodonta indet.), the first
Asiatic dryolestid (Dryolestoidea indet.) and several other presently
undetermined taxa (Mammalia indet.). This study describes a new member of
the mammal fauna from the Itat Formation that is the earliest known Asiatic
pretribosphenic mammal and the second Jurassic mammal species from Russia.



Schwarz-Wings, D., and Frey, E. 2008. Is there an option for a pneumatic
stabilization of sauropod necks? -- An experimental and anatomical approach.
Palaeontologia Electonica 11(3):17A 1-26.

ABSTRACT: The reconstructed distribution of the major pneumatic diverticula
systems in the sauropod neck might hint towards pneumatic stabilization or
operation of the long neck, which was investigated considering anatomical
and mechanical aspects of soft-tissue reconstructions in the neck of
sauropods as well as experimental data. The mechanical role of pneumatic
bodies in a generalized segmented beam of StyrodurT blocks, which was
stabilized by air-filled tube-like balloons, was tested with an experiment.
A support effect was evident already with one ventral pneumatic system.
Adding further pneumatic systems increased the load capacity of the beam.
Furthermore, the presence or absence of proximal intersegmental blocks,
pressure changes within the balloons, proximal fixation of the balloons or
their fixation at each segment respectively, and the degree of segmentation
of the pneumatic systems changed the efficiency of support.
     In the necks of sauropods, pneumatic support would hinge on the
specific reconstruction of the pneumatic diverticula, sufficiently high
pressures and a possibility for regulating pressure of the pneumatic system.
Only if pneumatic diverticula would extend beyond their bony boundaries at
the vertebral surface, and if one or more pressure regulating mechanisms
were present, would a support effect be an option. Because none of these
factors can be reliably reconstructed on an osteological basis, the
hypothesis of pneumatic neck support in sauropods remains hypothetical.
However, the combination of pneumatic support with other bracing mechanisms
in the sauropod neck results in a consistent constructional morphological
model for a pneu aided neck support in sauropods.




Parker, W.G., and Barton, B.J. 2008. New information on the Upper Triassic
archosauriform Vancleavea campi based on new material from the Chinle
Formation of Arizona. Palaeontologia Electonica 11(3):14A 1-20.

ABSTRACT: Two new partial skeletons from the Petrified Forest Member (Chinle
Formation) of Petrified Forest National Park are referable to Vancleavea
campi Long and Murry 1995. Although lacking good skull material, the new
specimens possess postcranial elements that are either absent or poorly
preserved in the holotype specimen. A phylogenetic analysis tentatively
suggests that Vancleavea campi represents a basal archosauriform more
derived than Erythrosuchus , Proterosuchus , and possibly Euparkeria.
Comparisons with undescribed material from the Chinle Formation near St.
Johns, Arizona, and Ghost Ranch, New Mexico, are needed to confirm this
placement and also to determine the taxonomic validity of the genus
Vancleavea.




~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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/

"I have made this letter longer
than usual because I lack the
time to make it shorter."
                      -- Blaise Pascal