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RE: Fossils in Argentinosaurus footprints
> From: owner-DINOSAUR@usc.edu [mailto:owner-DINOSAUR@usc.edu]
> On Behalf Of Martin Baeker
>
> Hi folks,
>
> my google skills have failed me: I have seen a TV documentary
> which showed an assembly of small fossils inside an
> Argentinosaurus footprint. However, I'm unable to find any
> reference for that.
>
> Any hints to a paper (or if possible a pdf) would be very
> welcome here...
The sauropod ID (and thus the continent) is totally wrong, but this seems to be
a misreporting of:
PALAIOS 25(2):112-125. 2010
DINOSAUR DEATH PITS FROM THE JURASSIC OF CHINA
full access
DAVID A. EBERTH1,*d, XU XING2, and JAMES M. CLARK3
Abstract
Three newly discovered bonebeds from the Shishugou Formation of Xinjiang,
China, are unusual in preserving vertically stacked and articulated to
associated skeletons of at least 18 small, non-avian theropod dinosaurs in pits
that are 1–2 m deep. The pits host a soft sediment-deformed mixture of alluvial
and volcanic mudstone and sandstone. There is no evidence that the pits were
discrete depressions in the topography that filled through time. Rather, they
appear to have been highly localized areas of liquefaction caused by
large-dinosaur (possibly sauropod) trampling of saturated sediments. Evidence
indicates that the small theropods, and some other small vertebrates, became
mired and died in these mud-filled pits. High quality skeletal preservation
suggests that most individuals were buried within days to months after their
deaths. Carcasses were buried successively, coming to rest above previously
buried individuals. In some cases, skeletal body parts became separated or were
removed, probably during scavenging. Given the large sizes of the pits relative
to the small body sizes of the vertebrates contained within them, we conclude
that small vertebrates (<3 m long and <1 m tall) were particularly susceptible
to miring at these sites. Although the small, presumably herbivorous
ceratosaur, Limusaurus inextricabilis, dominates the combined small theropod
assemblage from these bonebeds (minimum number of individuals [MNI] = 15),
there is no evidence that any biological features other than its small size and
a large, and possibly, gregarious local population were responsible for its
becoming mired in large numbers. A bias for small theropods in these bonebeds,
compared to their relatively low abundance in the overall Shishugou Formation
fauna, underscores that small theropods are underrepresented in Mesozoic fossil
assemblages collected from other ancient alluvial and paludal settings.
http://palaios.sepmonline.org/content/25/2/112.short
http://www.bioone.org/doi/abs/10.2110/palo.2009.p09-028r
Thomas R. Holtz, Jr.
Email: tholtz@umd.edu Phone: 301-405-4084
Office: Centreville 1216
Senior Lecturer, Vertebrate Paleontology
Dept. of Geology, University of Maryland
http://www.geol.umd.edu/~tholtz/
Fax: 301-314-9661
Faculty Director, Science & Global Change Program, College Park Scholars
http://www.geol.umd.edu/sgc
Fax: 301-314-9843
Mailing Address: Thomas R. Holtz, Jr.
Department of Geology
Building 237, Room 1117
University of Maryland
College Park, MD 20742 USA