Peace River Formation — Peace River Formation
Peace River Formation Qyd, Wikimedia Commons, CC BY SA 3.0

Formation · Neogene

Peace River Formation

Miocene unit, Florida

The Peace River Formation and the river gravels that rework it are Florida's most popular collecting ground: shark teeth including megalodon, dugong ribs, horse and mammoth teeth, glyptodont scutes, sloth and alligator material sieved from the river bed near Arcadia, Wauchula and Zolfo Springs. Because the gravels mix Miocene marine and Pleistocene land faunas, a Peace River label is a locality rather than an age. River-worn teeth are dark brown to black and lack the gloss of Bone Valley mine teeth; polished or oiled teeth should be described as such.

CountryUnited States
RegionFlorida
AgeMiocene
Age range~12–2 Ma
GroupHawthorn Group
Macrostrat rankFm· Macrostrat
Macrostrat age14.5–8.34 Ma· Macrostrat
Lithologyphosphorite, sand, clay, siliciclastic, carbonate· Macrostrat
Environmentdeltaic indet., marine· Macrostrat
Macrostrat columns2 column(s) sampled from 6 unit(s)· Macrostrat
Members (Macrostrat)Bone Valley· Macrostrat
PBDB collections52 collections, 346 occurrences· Paleobiology Database

Collecting and legality

The Peace River bed is sovereign state land: vertebrate fossils (bone, teeth) require the Florida Vertebrate Fossil Permit ($5 per year from the Florida Museum), and finds of scientific importance must be reported; shark teeth and invertebrates need no permit. Permit holders may sell what they find; commercial dredging is not allowed.

Lithology and setting

Phosphatic sands and clays with a basal gravel of reworked Miocene–Pleistocene bone, teeth and shark teeth, exposed in the bed of the Peace River and its tributaries.

Commonly recorded taxa (PBDB)

Genera most often recorded from this unit in the Paleobiology Database (first 200 occurrences): Calippus (13), Cormohipparion (12), Nannippus (10), Pomatodelphis (10), Borophagus (9), Neohipparion (9), Arcellites (7), Pseudhipparion (7), Callistosporites (6), Enhydritherium (5), Dinohippus (4), Mammut (4), Odontoceti (4), Phocidae (4), Balmeisporites (3).

Source: Paleobiology Database

Collecting rules

Elsewhere

Cite this article

Stratum Study. "Peace River Formation" (Formation). Stratum Study pack 2026.09, as of 2026-09-19. https://stratum.black/study/formations/peace-river-formation. Accessed 2026-09-20.

@misc{stratum-peace-river-formation,
  title        = {Peace River Formation},
  author       = {{Stratum Study}},
  howpublished = {\url{https://stratum.black/study/formations/peace-river-formation}},
  year         = {2026},
  note         = {Formation article, Stratum Study pack 2026.09, as of 2026-09-19; sources: stratum, macrostrat, pbdb, wikidata, commons. Accessed 2026-09-20.}
}

Citations carry the pack version and the article's as-of date so they resolve to the same text later. The facts themselves belong to the sources listed below; cite those for the science.