Gering B ( of the United States)
Where: Morrill County, Nebraska (41.7° N, 103.1° W: paleocoordinates 42.6° N, 97.3° W)
• coordinate based on political unit
When: Arikareean (29.5 - 18.5 Ma)
Environment/lithology: terrestrial
Primary reference: C. C. Swisher. 1982. Stratigraphy and biostratigraphy of the eastern portion of the Wildcat Ridge, western Nebraska. 1-172 [J. Alroy/J. Alroy/J. Marcot]more details
PaleoDB collection 17514: authorized by John Alroy, entered by John Alroy on 30.04.1994
Creative Commons license: CC BY (attribution)
Taxonomic list
• some specimens probably from Banner Co.
this unit appears to include the Twin Sister's Pumice Conglomerate of Mason and Swisher 1989, dated at 27.7 +/- 0.6 Ma (KA on sanidine) and redated by Tedford et al. 1996 at 28.31 +/- 0.03 Ma (SCLF AA); additional AA dates of 28.26 +/- 0.05 Ma (Chimney Rock Perrierite Ash) and 28.07 +/- 0.07 Ma (Roundhouse Rock Pisolitic Ash) appear to be from base of C and "near the top" of B and are barely distinguishable; 28.31 appears to be the best and should be used in calibration
this unit appears to include the Twin Sister's Pumice Conglomerate of Mason and Swisher 1989, dated at 27.7 +/- 0.6 Ma (KA on sanidine) and redated by Tedford et al. 1996 at 28.31 +/- 0.03 Ma (SCLF AA); additional AA dates of 28.26 +/- 0.05 Ma (Chimney Rock Perrierite Ash) and 28.07 +/- 0.07 Ma (Roundhouse Rock Pisolitic Ash) appear to be from base of C and "near the top" of B and are barely distinguishable; 28.31 appears to be the best and should be used in calibration
Show authors, comments, and common names
| Mammalia | |
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Archaeotherium sp. Leidy 1850 even-toed ungulate | |
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Merycoidodontidae indet. Cook 1912 oreodont
"Cyclopidius shanafeltae" = Leptauchenia oreodont
Sespia sp. Stock 1930 oreodont | |
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Thinohyus sp. Marsh 1875 peccary | |
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Agriochoerus sp. Leidy 1850 agriochoerid | |