Oxygen and Carbon Isotopic "Dissection" of Baculites compressus (Mollusca: Cephalopoda) from the Pierre Shale (Upper Campanian) of South Dakota: Implications for Paleoenvironmental Reconstructions

Palaios ◽  
1998 ◽  
Vol 13 (4) ◽  
pp. 376 ◽  
Author(s):  
James W. Fatherree ◽  
Peter J. Harries ◽  
Terrence M. Quinn
Keyword(s):  
South Dakota ◽  
Carbon Isotopic ◽  
Pierre Shale ◽  
Upper Campanian ◽  
Paleoenvironmental Reconstructions

scholarly journals 40Ar/39Ar date of a bentonite associated with a methane seep deposit in the upper Campanian Baculites compressus Zone, Pierre Shale, South Dakota

2018 ◽  
Vol 90 ◽  
pp. 90-96
Author(s):  
Neil H. Landman ◽  
Brian R. Jicha ◽  
J. Kirk Cochran ◽  
Matthew P. Garb ◽  
Shannon K. Brophy ◽  
...  
Keyword(s):  
South Dakota ◽  
Methane Seep ◽  
Pierre Shale ◽  
Upper Campanian

Foraminifera from the upper Campanian Pierre Shale methane cold-seeps, South Dakota

2018 ◽  
Vol 89 ◽  
pp. 235-247 ◽  
Author(s):  
Kimberly C. Meehan ◽  
Mariya Mego Vela ◽  
Nitara V. Gilles ◽  
Yvonne O. Chow ◽  
Connie Koo ◽  
...  
Keyword(s):  
South Dakota ◽  
Cold Seeps ◽  
Pierre Shale ◽  
Upper Campanian

scholarly journals Scanning electron microscope analysis of enamel microstructure in a Polycotylid (Plesiosauria) from the Pierre Shale Group, South Dakota, U.S.A.

2015 ◽  
Author(s):  
Jason J Testin
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
South Dakota ◽  
Enamel Microstructure ◽  
Scanning Electron Microscope Analysis ◽  
Pierre Shale ◽  
Electron Microscope Analysis ◽  
Dental Microstructure ◽  
Simple Cone ◽  
Scanning Electron

The teeth of polycotylid plesiosaurs are generally simple, cone shaped, non-serrated and only slightly recurved without distinct carinae. The surface of crowns are characterized by a series of vertical enamel wrinkles that are more highly developed on the lingual surface of the crown, and decrease in width and number toward the apex. Some of the most promising research related to fossil dentition, involves the analysis of surface and internal dental microstructure. This study, is an attempt to examine and describe polycotylid dental microstructure. It gives an overview of polycotylid plesiosaur enamel and dentine microstructures using a scanning electron microscope. Enamel type and structures vary, based on its position on the surface of the crown, and its perceived strength requirements. The dentition layer is “honeycombed” with tubular structure, possibly to provide nourishment to fast growing crowns. The study of crown microstructures may lead to a better understanding of polycotylid niche preference in the late Cretaceous oceans.

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