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Phunoichelys, new Jurassic turtle and other non-dino papers



Ben Creisler
bcreisler@gmail.com

A number of recent non-dino papers that may be of interest:

Haiyan Tong, Wilailuck Naksri, Eric Buffetaut, Varavudh Suteethorn,
Suravech Suteethorn, Uthumporn Deesri, Saitong Sila, Phornphen
Chanthasit and Julien Claude (2014)
A new primitive eucryptodiran turtle from the Upper Jurassic Phu
Kradung Formation of the Khorat Plateau, NE Thailand.
Geological Magazine (advance online publication)
DOI: http://dx.doi.org/10.1017/S0016756814000223
http://128.232.233.5/action/displayAbstract?fromPage=online&aid=9287193&fulltextType=RA&fileId=S0016756814000223

A new genus and new species of primitive eucryptodiran turtle,
Phunoichelys thirakhupti gen. et sp. nov., is described on the basis
of shell remains from the lower part of the Phu Kradung Formation, at
Phu Noi locality, Kalasin Province, NE Thailand. It is assigned to
Xinjiangchelyidae on the basis of the marginals covering the lateral
end of the costals and the anal scutes invading the hypoplastra. The
new taxon is further characterized by a low and rounded carapace
without a cervical notch; the whole carapace and plastron covered with
a clear ornamentation consisting of tiny irregular vermiculated
furrows; a complete neural series that reaches the suprapygal; a very
wide and short cervical scute; relatively wide vertebral scutes; and a
long first thoracic rib that extends along the full width of the first
costal. The sutured plastron/carapace connection and the marginals
covering the lateral end of the second to seventh costals suggest that
the turtles from Phu Noi may be related to some primitive
xinjiangchelyids from the Sichuan Basin. The discovery of a
xinjiangchelyid turtle in the lower part of the Phu Kradung Formation
supports a Late Jurassic age for that part of the formation.

==

Vivi Vajda, Adriana Ocampo, Embaie Ferrow & Christian Bender Koch (2014)
Nano particles as the primary cause for long-term sunlight suppression
at high southern latitudes following the Chicxulub impact – evidence
from ejecta deposits in Belize and Mexico.
Gondwana Research (advance online publication)
DOI: 10.1016/j.gr.2014.05.009
http://www.sciencedirect.com/science/article/pii/S1342937X14001889

Highlights
Proximal Chicxulub crater ejecta deposits (66 Ma) in Mexico and Belize
were studied
Mössbauer spectroscopy, XRD and sedimentology was applied
Goethite and haematite are the dominant Fe-oxide nano-phases
XRD results show that the target rock consists of both calcite and dolomite.
Darkness following impact partly due hydrous aerosols nucleated around
nano particles


Abstract
Life on Earth was sharply disrupted 66 million years ago as an
asteroid hit the sea-floor in what is today Yucatan Peninsula, Mexico.
Approximately 600 km3 of sedimentary rock were vaporized, ejected into
the atmosphere and subsequently deposited globally as an ejecta apron
and fallout layer. Proximal ejecta deposits occur in Belize and
southern Mexico where the so called Albion island spheroid bed' is
superimposed on the target rock (the Barton Creek Formation). We
analyzed the spheroid bed via Mössbauer spectroscopy, petrology, XRD,
and palynology at several sites ~ 350–500 km distance from the crater
centre. Our results show that the relative concentrations of Fe in
nano-phase goethite (α-FeOOH) are very high in the spheroid bed
samples from Albion Island (Belize) and from Ramonal South (Mexico),
but are low to absent in the spheroid bed at Ramonal North, and in the
Cretaceous target rock. Moreover, our study shows that goethite and
haematite are the dominant Fe-oxide nano-phases and the XRD results
show that the target rock consists of both calcite and dolomite. We
suggest that the heterogeneous composition of the spheroid bed between
the various sites reflects the different types of target rocks that
were dispersed within the rapidly expanding vapour plume and the
complex sorting processes involved in the formation of the ejecta
blanket. The distribution of the vaporized target rock strongly
influenced life on Earth at the close of the Mesozoic. However, the
comparatively thin K–Pg boundary clay in high-latitude Gondwanan
successions combined with evidence of catastrophic changes to the
biota in this region implies that the long-term sunlight suppression
in the Southern Hemisphere was mainly governed by the large quantities
of hydrous aerosols nucleated around sulphuric acid droplets or
nano-sized particles, such as the nano-phase Fe-oxides.


====

Free pdf:

Michel Hennebert (2014)
The Cretaceous-Paleogene boundary and its 405-kyr eccentricity cycle
phase: a new constraint on radiometric dating and astrochronology.
DOI : 10.4267/2042/mmmmm
http://paleopolis.rediris.es/cg/1409/index.html


Radiometric dating and astrochronologic dating still suffer
discrepancies without knowing which one gives the most reliable
results. A new tool is proposed to constrain both the approaches. The
phase of the 405-kyr signal with respect to the Cretaceous - Paleogene
boundary event has been determined in the Aïn Settara section (Kalaat
Senan, central Tunisia). We use this phase value (Option 2), as well
as an average of phase values obtained from the literature (Option 1),
to examine the relationship linking both the radiometric (absolute)
age assigned to the K-Pg boundary and the Cenozoic average-value of
the ~405-kyr eccentricity period. A new useful constraint emerges: to
any absolute age assumed for the K-Pg boundary corresponds a value of
the mean Cenozoic 405-kyr period, and vice versa.
Supposing a K-Pg boundary radiometric age in the vicinity of 66.0 Ma,
then the number of entire cycles (comprised between two minima of the
405-kyr eccentricity signal) within the Cenozoic Period could only be
equal to 163. When adding to this figure the parts of the cycles
preceding and following these 163 entire cycles the total duration of
the Cenozoic Era becomes equal to 163.168 cycles (Option 1) or 163.081
cycles (Option 2).
We propose to grant a special interest to the determination of the
405-kyr cycle phase at stratigraphically well documented levels,
particularly those that correspond to world-wide, sudden and
catastrophic events, that are well located in time by reliable
radiometric dates.

=====

Free pdf:

Nicholas P. Edwards, Phillip L. Manning and Roy A. Wogelius (2014)
Pigments through time.
Pigment Cell & Melanoma Research (advance online publication)
DOI: 10.1111/pcmr.12271
http://onlinelibrary.wiley.com/doi/10.1111/pcmr.12271/pdf



===

The new issue of open-access Acta Palaeontologica Polonica 59 (2) 2014
is now out online, meaning some articles previously in MS form are now
in final form:

http://app.pan.pl/issue/issue/current.html


Rebecca Hofmann, Koen Stein, and P. Martin Sander (2014)
Constraints on the lamina density of laminar bone architecture of
large-bodied dinosaurs and mammals.
Acta Palaeontologica Polonica 59 (2), 2014: 287-294
doi: http://dx.doi.org/10.4202/app.2012.0149

***
Brandon P. Hedrick, Allison R. Tumarkin-Deratzian, and Peter Dodson (2014)
Bone microstructure and relative age of the holotype specimen of the
diplodocoid sauropod dinosaur Suuwassea emilieae.
Acta Palaeontologica Polonica 59 (2), 2014: 295-304
doi: http://dx.doi.org/10.4202/app.2012.0049

***
Tai Kubo and Mugino O. Kubo (2014)
Dental microwear of a Late Triassic dinosauriform, Silesaurus opolensis.
Acta Palaeontologica Polonica 59 (2), 2014: 305-312
doi: http://dx.doi.org/10.4202/app.2013.0027

**
Adán Pérez-García, José Miguel Gasulla, and Francisco Ortega (2014)
A new turtle species of Brodiechelys from the Early Cretaceous of
Spain: Systematic and palaeobiogeographic implications.
Acta Palaeontologica Polonica 59 (2), 2014: 333-342
doi: http://dx.doi.org/10.4202/app.2012.0059

***

Yasuhisa Nakajima, Alexandra Houssaye, and Hideki Endo (2014)
Osteohistology of the Early Triassic ichthyopterygian reptile
Utatsusaurus hataii: Implications for early ichthyosaur biology.
Acta Palaeontologica Polonica 59 (2), 2014: 343-352
doi: http://dx.doi.org/10.4202/app.2012.0045