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Beijing dinosaur track site + other dino-related papers (free pdfs)

Ben Creisler

A number recent papers on dino- or Mesozoic-related topics that may be
interest. The pdfs are free.

HE Qing,  ZHANG Jianping,  XING Lida,  LU Shuo &  QU Haiying (2015)
Sedimentary environment of Tuchengzi Formation dinosaur track site in
Qianjiadian area, Yanqing County, Beijing.   (in Chinese)
Geological Bulletin of China 34(9): 1726-1734

Few fossils have been found in Late Jurassic Tuchengzi Formation from
Qianjiadian District, Yanqing County, Beijing. Nevertheless, the new
dinosaur footprints are important evidence of dinosaurs that once
lived in Beijing. The study of its sedimentary environment is very
important for reconstructing the living environment of dinosaur fauna.
There are theropod, sauropod and possible ornithopod tracks in the
study area. Based on stratigraphic, petrological, paleontological and
sedimentary research methods, the authors used the integrated
characteristics of field section, dinosaur tracks distribution,
sedimentary structrue and grain size distribution to study the
sedimentary environment of the third member of Tuchengzi Formation in
Qianjiadian area. There was a volcaniclastic shallow lake here and the
dinosaur tracks were formed in a lakeshore environment.


Nouvelles données sédimentologiques et paléontologiques (charophytes,
ostracodes, coquilles d’œuf de dinosaure) sur la Formation du Tigri
(Sénonien des Hauts Plateaux méridionaux, Maroc oriental) ;
paléoenvironnements et évolution paléogéographique.  (in French)
[New sedimentological and paleontological data (Charophytes,
Ostracods, Dinosaur eggshell) in the Tigri Formation (Senonian of the
Southern High Plateaus, Eastern Morocco) ; paleoenvironments and
paleogeographic evolution. ]
Revue de Paléobiologie 34 (1) : 85-111

In the Southern High Plateaus (Eastern Morocco), stratigraphical,
paleontological and sedimentological studies were performed in the
detrital red series (sandstones and conglomerates of the Tigri
Formation) which cover the Cenomanian–Turonian marine deposits.

The lower part of the Tigri Formation shows five brackish or marine
incursions with oligospecific faunas consisting of small benthic
foraminifera and marine ostracods. The continental upper part of the
Formation provided two localities with microfossils : the first
contains freshwater to oligohaline ostracods, charophytes (Mesochara
sp.), a fragment of dinosaur eggshell (Pseudomegaloolithus atlasi),
but also a level with abundant sea urchin spines indicating the last
Cretaceous marine transgression ; the second locality has yielded
charophytes only (Mesochara ameghinoi and Stephanochara sp.).


Maura Brunetti, Christian Vérard & Peter O. Baumgartner (2015)
Modelling the Middle Jurassic ocean circulation.
Journal of Palaeogeography (advance online publication)

We present coupled ocean–sea-ice simulations of the Middle Jurassic
(∼165 Ma) when Laurasia and Gondwana began drifting apart and gave
rise to the formation of the Atlantic Ocean. Since the opening of the
Proto-Caribbean is not well constrained by geological records, both
the configurations with and without an open connection between the
Proto-Caribbean and Panthalassa have been examined. We use a sea-floor
bathymetry obtained by a recently developed three-dimensional (3D)
elevation model which compiles geological, palaeogeographical and
geophysical data. Our original approach consists in coupling this
elevation model, which is based on detailed reconstructions of oceanic
realms, with a dynamical ocean circulation model. We find that the
Middle Jurassic bathymetry of the Central Atlantic and Proto-Caribbean
seaway only allows for a weak current of the order of 2 Sv in the
upper 1000 m even if the system is open to the west. The effect of
closing the western boundary of the Proto-Caribbean is to increase the
transport related to barotropic gyres in the southern hemisphere and
to change water properties, such as salinity, in the Neo-Tethys. Weak
upwelling rates are found in the nascent Atlantic Ocean in the
presence of this superficial current and we discuss their
compatibility with deep-sea sedimentological records in this region.


Harry Allard, Simon C. Carpenter, Christopher J. Duffin & Michael J.
Benton (2015)
Microvertebrates from the classic Rhaetian bone beds of Manor Farm
Quarry, near Aust (Bristol, UK).
Proceedings of the Geologists' Association (advance online publication)

Free pdf:


Manor Farm Quarry shows a detailed record of the entire Rhaetian
section typical of southwest England. It has yielded a standard
Rhaetian marine fauna, including eight species of sharks, four species
of actinopterygian fishes, and the reptiles Pachystropheus and
Ichthyosaurus, all of which are widely known from coeval sites. An
unusual feature is the occurrence of an unidentified coelacanth,
represented by nine isolated quadrates showing a broad range of sizes.
The site has also provided information on the occurrence of
vertebrates through five distinctive bone-bearing horizons, including
the famous basal Westbury Formation bone bed, as well as a second
horizon with bones at the top of the Westbury Formation, and three
within the overlying Cotham Member of the Lilstock Formation. These
show substantial differences, especially between the basal bone bed
and the four overlying bone-rich units. The basal Westbury Formation
bone bed is dominated by shark remains (73%, compared to 23–30% in the
four overlying units), most notably, teeth of Rhomphaiodon minor and
Lissodus minimus, which are absent or rare in higher beds. Further,
teeth of the bony fishes Gyrolepis albertii and Severnichthys
acuminatus are rare in the basal bone bed, but abundant at the top of
the Westbury Formation and through the Cotham Member, and the sharks
Duffinselache holwellensis and Pseudocetorhinus pickfordi, absent in
the basal bone bed, are relatively abundant in the four overlying
bone-bearing units. These differences in faunal lists and in relative
proportions probably do not reflect sampling, but some major
differences in ecology and evolution.