ammonites
USGS Loc. 4993 - Holland [Jackson Bluff Fm] (Pliocene of the United States)

Where: Leon County, Florida (31.0° N, 84.5° W: paleocoordinates 31.1° N, 83.9° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Jackson Bluff Formation (Alum Bluff Group), Late/Upper Pliocene (3.6 - 2.6 Ma)

• Lower upper Miocene bed. Ecphora Zone of Choctawhatchee Formation, Alum Bluff Group. The Ecphora zone, from which the collection is derived, is typically exposed in the upper fossiliferous bed unconformably overlying the Chipola Formation at Alum Bluff, Apachicola River. The bed ranges in thickness from 15-25 ft at different places along the bluff. Late Miocene age based on recent lithostratigraphy. Local section name = Holland, Basinal/regional section name = Leon. Placed in Jackson Bluff Fm (and hence Late Pliocene) by enterer.

• group of beds-level stratigraphic resolution

Environment/lithology: coastal; unlithified, shelly/skeletal, blue, sandy claystone

• No reported geologic or paleoenvironmental data. Probably shallow water siliciclastic depositional environment.
• The sediments comprising the Ecphora Zone consist of very fossiliferous, sandy clay, which is bluish where unweathered. Lithification data not reported, but all figured specimens appear to be free of matrix so an unlithified classification is assigned.

Size class: macrofossils

Reposited in the USNM

• Specimens are lodged in USNM collections. Collected by G.C. Matson (1908)

Primary reference: W. C. Mansfield. 1930. Miocene gastropods and scaphopods of the Choctawatchee Formation of Florida. Florida State Geological Survey Bulletin 3 [A. Miller/A. Hendy/A. Hendy] more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 59489: authorized by Austin Hendy, entered by Austin Hendy on 03.04.2006

Creative Commons license: CC BY-NC-ND (attribution-noncommercial-no derivatives)