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Danek Edmontosaurus Bonebed: Special Issue of Canadian Journal of Earth Sciences



Ben Creisler
bcreisler@gmail.com

The new issue of the Canadian Journal Earth Sciences is devoted to the
Danek Edmontosaurus Bonebed.  The intro material is free.

free pdf:

Michael E. Burns, Clive Coy, Victoria M. Arbour, Philip J. Currie &
Eva B. Koppelhus (2014)
The Danek Edmontosaurus Bonebed: new insights on the systematics,
biogeography, and palaeoecology of Late Cretaceous dinosaur
communities.
Canadian Journal of Earth Sciences, 2014, 51(11): v-vii
doi: 10.1139/cjes-2014-0217
http://www.nrcresearchpress.com/doi/pdf/10.1139/cjes-2014-0217?src=recsys

***

David A. Eberth & Phil R. Bell (2014)
Stratigraphy of the Danek Bonebed (Upper Cretaceous Horseshoe Canyon
Formation, central Alberta) and correlations with strata in the
Drumheller and Grande Prairie regions.
Canadian Journal of Earth Sciences, 2014, 51(11): 975-981
doi:  10.1139/cjes-2014-0069
http://www.nrcresearchpress.com/doi/abs/10.1139/cjes-2014-0069?src=recsys#.VI9gQCvF_To

Although considerable work has been conducted on the stratigraphy and
dinosaur assemblages of the Horseshoe Canyon Formation of southern
Alberta, equivalent strata and assemblages in central Alberta remain
poorly understood. Data from the Danek Bonebed (Edmonton, Alberta) are
beginning to fill this gap. The bonebed occurs 4 m above the #9 Big
Island Coal Seam. This stratigraphic position lies just below the
middle of the Horseshoe Canyon Formation in the Edmonton region, and
also lies below a thick, stratigraphically significant non-coaly
interval that is expressed throughout central and southern Alberta.
The stratigraphic position of the Danek Bonebed equates best with the
uppermost Horsethief Member of the Horseshoe Canyon Formation in the
Drumheller region and the upper part of Unit 4 of the Wapiti Formation
in the Grande Prairie region. In both Drumheller and Grande Prairie,
the correlated position of the bonebed underlies a zone of marine
transgression (Drumheller Marine Tongue), which, in turn, includes the
Campanian–Maastrichtian boundary. In the context of Geologic Time
Scale 2004, we infer a late Campanian age of 71.0–71.3 Ma for the
bonebed. The Danek’s dinosaurian assemblage is limited taxonomically,
but compares well with the Edmontosaurus regalis – Pachyrhinosaurus
canadensis fossil assemblage zone in the Drumheller region. We propose
that a mega-herbivore faunal assemblage, characterized by
Edmontosaurus and Pachyrhinosaurus, extended continuously across the
climatically wet coastal plain of latest Campanian southern and
central Alberta, and likely extended northwest into the North Slope of
Alaska, where it persisted into the early Maastrichtian.
***

Joshua H.F.L. Davies, Jörn-Frederik Wotzlaw, Alexander P. Wolfe &
Larry M. Heaman (2014)
Assessing the age of the Late Cretaceous Danek Bonebed with U–Pb geochronology.
Canadian Journal of Earth Sciences, 2014, 51(11): 982-986,
doi: 10.1139/cjes-2014-0136
http://www.nrcresearchpress.com/doi/abs/10.1139/cjes-2014-0136?src=recsys#.VI9gmivF_To


An ash-rich volcaniclastic sandstone immediately underlying
dinosaur-rich material from the Danek Bonebed in the Horseshoe Canyon
Formation (HCF), Edmonton, Alberta, Canada, contains accessory zircon,
which have been dated employing U–Pb geochronology. Both
laser-ablation inductively coupled plasma mass spectrometry
(LA-ICP-MS) and chemical abrasion isotope dilution thermal ionization
mass spectrometry (ID-TIMS) U–Pb analyses have been conducted. The
zircon age distributions are complex with U–Pb dates ranging from
Precambrian to Cretaceous. We consider the youngest ID-TIMS 206Pb/238U
date of 71.923 ± 0.068 Ma as the maximum deposition age of the
ash-rich sandstone, placing the overlying Danek bonebed in the early
Maastrichtian. This age is compatible with the paleontological
assemblage from the Danek Bonebed and the regional stratigraphy. The
zircon age distribution also implies that the HCF had a complex
provenance of the detritus with some Archean and Proterozoic zircons,
a group of Mesozoic, and a large compliment of Cretaceous grains. The
results highlight the importance of high precision geochronology in
constraining the age of important fossil deposits such as the Danek
Bonebed.
***

Katherine Bramble, Michael E. Burns & Philip J. Currie (2014)
Enhancing bonebed mapping with GIS technology using the Danek Bonebed
(Upper Cretaceous Horseshoe Canyon Formation, Edmonton, Alberta,
Canada) as a case study.
Canadian Journal of Earth Sciences, 2014, 51(11): 987-991
doi: 10.1139/cjes-2014-0056


The Danek Bonebed is a monodominant Edmontosaurus bonebed preserving
predominantly disarticulated material from the Upper Campanian
Horseshoe Canyon Formation within the city limits of Edmonton,
Alberta, Canada. To date, at least six dinosaur taxa have been
identified at the site: Albertosaurus sarcophagus, Chasmosaurinae
indet., Dromaeosauridae indet., Edmontosaurus regalis, Ornithomimidae
indet., and Troodontidae indet. This bonebed has been used as a case
study for creating a digital, searchable bonebed map using a
geographic information system (GIS) platform. The original quarry maps
produced on site are refined when digitized with new anatomical
information gathered during preparation of collected specimens. Each
specimen is labeled with the known specimen identification, quarry
coordinates, and catalogue number. Creating a digital map of the
bonebed allows easier interpretation of data and the ability to share
maps to compare specific elements within the bonebed.



==

News release:

http://www.nrcresearchpress.com/doi/story/10.4141/news.2014.12.14.295#.VI9hXivF_To

http://phys.org/news/2014-12-edmontosaurus-regalis-danek-bonebed-featured.html