Red Division (Miocene of the United States)

Also known as Red Division Quarry

Where: San Bernardino County, California (34.8° N, 117.0° W: paleocoordinates 34.1° N, 112.3° W)

• coordinate based on political unit

• small collection-level geographic resolution

When: Owl Conglomerate Member (Barstow Formation), Barstovian (16.3 - 12.5 Ma)

Environment/lithology: terrestrial

Primary reference: M. O. Woodburne, R. H. Tedford, and C. C. Swisher, III. 1990. Lithostratigraphy, biostratigraphy, and geochronology of the Barstow Formation, Mojave Desert, southern California. Geological Society America Bulletin 102(4):459-477 [J. Alroy/J. Alroy/J. Alroy]more details

PaleoDB collection 19513: authorized by John Alroy, entered by John Alroy on 18.02.1993

Creative Commons license: CC BY (attribution)

Taxonomic list

• underlies Rak Tuff, dated at 16.3 +/- 0.3 Ma (KA on biotite, average of three analyses)
Woodburne 1996b makes a plausibility argument that the true date of the tuff is 16.5 - 16.7 Ma, but his correlation to the paleomagnetic time scale is based on an interval that has four apparent normal chrons but "should" have three; this suggests that the paleomag is too ambiguous for such a fine level of correlation
Mammalia
 Perissodactyla - Equidae
Parapliohippus carrizoensis Dougherty 1940 horse
 Artiodactyla - Camelidae
Paramiolabis cf. tenuis Matthew 1924 camel
Miolabis sp. Hay 1899 camel
sensu stricto
 Artiodactyla - Antilocapridae
Merycodus cf. joraki Frick 1937 pronghorn
 Artiodactyla - Merycoidodontidae
"Merychyus smithi" = Ticholeptus zygomaticus
"Merychyus smithi" = Ticholeptus zygomaticus Cope 1878 oreodont