Alum Bluff (Miocene of the United States)

Where: Liberty County, Florida (30.2° N, 84.9° W: paleocoordinates 30.5° N, 82.0° W)

• coordinate based on political unit

When: "Fort Preston sand" Formation, Miocene (23.0 - 5.3 Ma)

Environment/lithology: terrestrial

Primary reference: J. D. Bryant, B. J. MacFadden, and P. A. Mueller. 1992. Improved chronologic resolution of the Hawthorn and the Alum Bluff Groups in northern Florida: Implications for Miocene chronostratigraphy. Geological Society America Bulletin 104(2):208-218 [J. Alroy/J. Alroy/P. Wagner]more details

PaleoDB collection 18503: authorized by John Alroy, entered by John Alroy on 27.07.1994, edited by Mark Uhen

Creative Commons license: CC BY (attribution)

Taxonomic list

• replaces list of Olsen 1964
underlying horizon in same section dated at 18.3, 18.4, 18.6, and 18.9 +/- 1.0 Ma (Sr isotope) - average is 18.55 Ma; diagenesis is considered to be minimal
Mammalia
 Perissodactyla - Equidae
Anchitheriinae indet. Leidy 1869 anchitheriine horse
includes "Parahippus leonensis" of Olsen 1964
"Merychippus" gunteri Simpson 1930 horse
 Perissodactyla - Rhinocerotidae
Rhinocerotidae indet. Gray 1821 rhinoceros
 Artiodactyla - Protoceratidae
Prosynthetoceras texanus2 Hay 1924 protoceratid
Echinoidea
 Clypeasteroida - Fibulariidae
Echinocyamus chipolanus1 Cooke 1942 sand dollar